1
|
Duke SO, Pan Z, Bajsa-Hirschel J, Tamang P, Hammerschmidt R, Lorsbach BA, Sparks TC. Molecular Targets of Herbicides and Fungicides─Are There Useful Overlaps for Fungicide Discovery? JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY 2023; 71:20532-20548. [PMID: 38100716 PMCID: PMC10755756 DOI: 10.1021/acs.jafc.3c07166] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/03/2023] [Revised: 11/20/2023] [Accepted: 11/21/2023] [Indexed: 12/17/2023]
Abstract
New fungicide modes of action are needed for fungicide resistance management strategies. Several commercial herbicide targets found in fungi that are not utilized by commercial fungicides are discussed as possible fungicide molecular targets. These are acetyl CoA carboxylase, acetolactate synthase, 5-enolpyruvylshikimate-3-phosphate synthase, glutamine synthase, phytoene desaturase, protoporphyrinogen oxidase, long-chain fatty acid synthase, dihydropteroate synthase, hydroxyphenyl pyruvate dioxygenase, and Ser/Thr protein phosphatase. Some of the inhibitors of these herbicide targets appear to be either good fungicides or good leads for new fungicides. For example, some acetolactate synthase and dihydropteroate inhibitors are excellent fungicides. There is evidence that some herbicides have indirect benefits to certain crops due to their effects on fungal crop pathogens. Using a pesticide with both herbicide and fungicide activities based on the same molecular target could reduce the total amount of pesticide used. The limitations of such a product are discussed.
Collapse
Affiliation(s)
- Stephen O. Duke
- National
Center for Natural Products Research, School of Pharmacy, University of Mississippi, University 38667, United States
| | - Zhiqiang Pan
- Natural
Products Utilization Research Unit, United
States Department of Agriculture, University 38667, United States
| | - Joanna Bajsa-Hirschel
- Natural
Products Utilization Research Unit, United
States Department of Agriculture, University 38667, United States
| | - Prabin Tamang
- Natural
Products Utilization Research Unit, United
States Department of Agriculture, University 38667, United States
| | - Raymond Hammerschmidt
- Department
of Plant, Soil and Microbial Sciences, Michigan
State University, East Lansing, Michigan 48824, United States
| | - Beth A. Lorsbach
- Nufarm, 4020 Aerial Center Parkway, Morrisville, North Carolina 27560, United States
| | | |
Collapse
|
2
|
Staunton PM, Peters AJ, Seoighe C. Somatic mutations inferred from RNA-seq data highlight the contribution of replication timing to mutation rate variation in a model plant. Genetics 2023; 225:iyad128. [PMID: 37450609 PMCID: PMC10550316 DOI: 10.1093/genetics/iyad128] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2023] [Revised: 03/23/2023] [Accepted: 06/11/2023] [Indexed: 07/18/2023] Open
Abstract
Variation in the rates and characteristics of germline and somatic mutations across the genome of an organism is informative about DNA damage and repair processes and can also shed light on aspects of organism physiology and evolution. We adapted a recently developed method for inferring somatic mutations from bulk RNA-seq data and applied it to a large collection of Arabidopsis thaliana accessions. The wide range of genomic data types available for A. thaliana enabled us to investigate the relationships of multiple genomic features with the variation in the somatic mutation rate across the genome of this model plant. We observed that late replicated regions showed evidence of an elevated rate of somatic mutation compared to genomic regions that are replicated early. We identified transcriptional strand asymmetries, consistent with the effects of transcription-coupled damage and/or repair. We also observed a negative relationship between the inferred somatic mutation count and the H3K36me3 histone mark which is well documented in the literature of human systems. In addition, we were able to support previous reports of an inverse relationship between inferred somatic mutation count and guanine-cytosine content as well as a positive relationship between inferred somatic mutation count and DNA methylation for both cytosine and noncytosine mutations.
Collapse
Affiliation(s)
- Patrick M Staunton
- School of Mathematical and Statistical Sciences, University of Galway, Galway H91 TK33, Ireland
| | - Andrew J Peters
- School of Mathematical and Statistical Sciences, University of Galway, Galway H91 TK33, Ireland
| | - Cathal Seoighe
- School of Mathematical and Statistical Sciences, University of Galway, Galway H91 TK33, Ireland
| |
Collapse
|
3
|
Retnamma J, Sarath S, Balachandran KK, Krishnan SS, Karnan C, Arunpandi N, Alok KT, Ramanamurty MV. Environmental and human facets of the waterweed proliferation in a Vast Tropical Ramsar Wetland-Vembanad Lake System. ENVIRONMENTAL MONITORING AND ASSESSMENT 2023; 195:900. [PMID: 37380928 DOI: 10.1007/s10661-023-11417-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/05/2022] [Accepted: 05/22/2023] [Indexed: 06/30/2023]
Abstract
The Vembanad Lake and its associated low-lying areas and network of canals (hereafter VBL) form the major part of India's second-largest Ramsar wetland (1512 km2) located in Kerala State along India's southwest coast. The extensive VBL has a large fishery, inland waterways, and popular tourist attractions that support the livelihoods of thousands of people. Over the last several decades, the proliferation of water weeds in the VBL has alarmingly increased, causing many adverse ecological and socioeconomic effects. This study based on a review and synthesis of long-term data introduced the environmental and human dimensions of water weed proliferation in the VBL. Eichhornia (= Pontederia) crassipes, Monochoria vaginalis, Salvinia molesta, Limnocharis flava, Pistia stratiotes, and Hydrilla verticillata are the most troublesome water weeds in the VBL, with the first three being the most widespread. They were mostly imported to India long ago before becoming a part of the VBL. These weeds harmed water quality, waterways, agriculture, fisheries, disease vector management, as well as the vertical and horizontal shrinkage of the VBL through increased siltation and faster ecological succession. The inherently fragile VBL was harmed by extensive and long-term reclamation, the construction of saltwater barrages, and many landfill roads that crisscross water bodies serving as coastal dams, creating water stagnation by blocking natural flushing/ventilation by periodic tides from the adjacent southeastern Arabian Sea. These ecological imbalances were exacerbated by excessive fertiliser use in agricultural areas, as well as the addition of nutrient-rich domestic and municipal sewage, which provided an adequate supply of nutrients and a favourable habitat for the expansion of water weeds. Furthermore, because of recurrent floods and a changing ecology in the VBL, the water weed proliferation has become a more significant problem, with the potential to disrupt their current distribution pattern and spread in the future.
Collapse
Affiliation(s)
| | - S Sarath
- CSIR-National Institute of Oceanography, Regional Centre, Kochi, India
| | - K K Balachandran
- CSIR-National Institute of Oceanography, Regional Centre, Kochi, India
| | - S Santhi Krishnan
- CSIR-National Institute of Oceanography, Regional Centre, Kochi, India
| | - C Karnan
- CSIR-National Institute of Oceanography, Regional Centre, Kochi, India
- CSIR-National Institute of Oceanography, Dona Paula, Goa, India
| | - N Arunpandi
- CSIR-National Institute of Oceanography, Regional Centre, Kochi, India
| | - K T Alok
- CSIR-National Institute of Oceanography, Regional Centre, Kochi, India
| | - M V Ramanamurty
- Ministry of Earth Sciences, National Centre for Coastal Research, Chennai, India
| |
Collapse
|
4
|
Zou Y, Zhao B, Cao S, Guan Y, Liu L, Ji M. Mutation at the 197 site and P450-mediated metabolic resistance are involved in bensulfuron-methyl resistance in Sagittaria trifolia. PLANT SCIENCE : AN INTERNATIONAL JOURNAL OF EXPERIMENTAL PLANT BIOLOGY 2023; 331:111700. [PMID: 37028456 DOI: 10.1016/j.plantsci.2023.111700] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/21/2022] [Revised: 04/02/2023] [Accepted: 04/05/2023] [Indexed: 06/19/2023]
Abstract
Sagittaria trifolia control is threatened by the emergence of resistance to acetolactate synthase (ALS)-inhibiting herbicides. Hence, we systematically uncovered the molecular mechanism of resistance to the main herbicide (bensulfuron-methyl) in Liaoning Province from target-site and non-target-site resistance perspectives. The suspected resistant population (TR-1) exhibited high-level resistance. A new amino acid substitution (Pro-197-Ala) in resistant Sagittaria trifolia for ALS was detected, and the molecular docking results showed that the spatial structure of ALS changed significantly after the substitution, manifested by an increase in the number of contacted amino acid residues and the disappearance of hydrogen bonds. Dose-response test of transgenic Arabidopsis thaliana further demonstrated that the Pro-197-Ala substitution conferred bensulfuron-methyl resistance. The assays found that the sensitivity of the ALS enzyme in TR-1 to this herbicide was decreased in vitro; and this population had developed resistance to other types of ALS-inhibiting herbicides. Furthermore, the resistance of TR-1 to bensulfuron-methyl was significantly alleviated after co-treatment with a P450-inhibitor (malathion). TR-1 metabolized bensulfuron-methyl significantly faster than sensitive population (TS-1) did, but this gap was narrowed after malathion treatment. Overall, the resistance of Sagittaria trifolia to bensulfuron-methyl was derived from the mutation of the target-site gene and the enhancement of the P450s-mediated detoxification metabolism.
Collapse
Affiliation(s)
- Yize Zou
- College of Plant Protection, Shenyang Agricultural University, No. 120 Dongling Road, Shenhe District, Shenyang City 110866, China
| | - Bochui Zhao
- Institute of Cereal and Oil Crops, Hebei Academy of Agriculture and Forestry Sciences, Shijiazhuang 050035, China
| | - Shihan Cao
- College of Plant Protection, Shenyang Agricultural University, No. 120 Dongling Road, Shenhe District, Shenyang City 110866, China
| | - Yidi Guan
- College of Plant Protection, Shenyang Agricultural University, No. 120 Dongling Road, Shenhe District, Shenyang City 110866, China
| | - Liru Liu
- College of Plant Protection, Shenyang Agricultural University, No. 120 Dongling Road, Shenhe District, Shenyang City 110866, China
| | - Mingshan Ji
- College of Plant Protection, Shenyang Agricultural University, No. 120 Dongling Road, Shenhe District, Shenyang City 110866, China.
| |
Collapse
|
5
|
Aquatic Plant Invasion and Management in Riverine Reservoirs: Proactive Management via a Priori Simulation of Management Alternatives. DIVERSITY 2022. [DOI: 10.3390/d14121113] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
Negative impacts from aquatic invasive plants in the United States include economic costs, loss of commercial and recreational use, and environmental damage. Simulation models are valuable tools for predicting the invasion potentials of species and for the management of existing infestations. We developed a spatially explicit, agent-based model representing the invasion, growth, and senescence of aquatic weeds as functions of day length, water temperature, water depth, and the response of aquatic weeds to biological control. As a case study to evaluate its potential utility, we parameterized the model to represent two historical invasions (1975–1983 and 2004–2007) of Hydrilla (Hydrilla verticillata (L. fil.) Royle) in Lake Conroe, Texas, USA, and their subsequent biological control using grass carp (Ctenopharyngodon idella). Results of several hypothetical alternative management schemes indicated that grass carp stocking densities needed to control Hydrilla infestation increased exponentially as the lag time between initial invasion and initial stocking increased, whereas stocking densities needed to control infestation decreased as the amount of time allowed to control the infestation increased. Predictions such as those produced by our model aid managers in developing proactive management plans for areas most likely to be invaded.
Collapse
|
6
|
Wang N, Bai S, Bei F, Zhao N, Jia S, Jin T, Wang J, Wang H, Liu W. Resistance to ALS inhibitors conferred by non-target-site resistance mechanisms in Myosoton aquaticum L. PESTICIDE BIOCHEMISTRY AND PHYSIOLOGY 2022; 184:105067. [PMID: 35715029 DOI: 10.1016/j.pestbp.2022.105067] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/09/2021] [Revised: 02/23/2022] [Accepted: 02/28/2022] [Indexed: 06/15/2023]
Abstract
Myosoton aquaticum L. is a competitive broadleaf weed commonly found in wheat fields in China and has become challenging due to its evolving herbicide resistance. In this study, one subpopulation, RF1 (derived from the tribenuron-methyl-resistant population HN10), with none of the known acetolactate synthase (ALS) resistance mutations was confirmed to exhibit resistance to tribenuron-methyl (SU), pyrithiobac‑sodium (PTB), florasulam (TP), flucarbazone-Na (SCT), and diflufenican (PDS). In vitro ALS activity assays showed that the total ALS activity of RF1 was lower than that of the susceptible (S) population. However, there was no difference in ALS gene expression induced by tribenuron-methyl between the two populations. The combination of the cytochrome P450 monooxygenase (P450) inhibitor malathion and tribenuron-methyl resulted in the RF1 population behaving like the S population. The rapid P450-mediated tribenuron-methyl metabolism in RF1 plants was also confirmed by liquid chromatography tandem mass spectrometry (LC-MS/MS) analysis. In addition, approximately equal glutathione S-transferase (GST) activity was observed in RF1 and S plants of untreated and tribenuron-methyl treated groups. This study reported one M. aquaticum L. population without ALS resistance mutations exhibiting resistance to ALS inhibitors and the PDS inhibitor diflufenican, and the non-target-site resistance mechanism played a vital role in herbicide resistance.
Collapse
Affiliation(s)
- Nan Wang
- College of Plant Protection, Shandong Agricultural University, Tai'an 271018, Shandong, PR China
| | - Shuang Bai
- College of Plant Health and Medicine, Qingdao Agricultural University, Qingdao 266000, PR China
| | - Feng Bei
- Tai'an Customs, Tai'an 271018, Shandong, PR China
| | - Ning Zhao
- School of Plant Protection, Anhui Agricultural University, Hefei 230036, PR China
| | - Sisi Jia
- Tai'an Customs, Tai'an 271018, Shandong, PR China
| | - Tao Jin
- Qingdao Kingagroot Chemical Compound Co., Ltd., Qingdao 266000, PR China
| | - Jinxin Wang
- College of Plant Protection, Shandong Agricultural University, Tai'an 271018, Shandong, PR China
| | - Hengzhi Wang
- College of Plant Protection, Shandong Agricultural University, Tai'an 271018, Shandong, PR China.
| | - Weitang Liu
- College of Plant Protection, Shandong Agricultural University, Tai'an 271018, Shandong, PR China.
| |
Collapse
|
7
|
Gupta P, Hirschberg J. The Genetic Components of a Natural Color Palette: A Comprehensive List of Carotenoid Pathway Mutations in Plants. FRONTIERS IN PLANT SCIENCE 2022; 12:806184. [PMID: 35069664 PMCID: PMC8770946 DOI: 10.3389/fpls.2021.806184] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/31/2021] [Accepted: 12/08/2021] [Indexed: 05/16/2023]
Abstract
Carotenoids comprise the most widely distributed natural pigments. In plants, they play indispensable roles in photosynthesis, furnish colors to flowers and fruit and serve as precursor molecules for the synthesis of apocarotenoids, including aroma and scent, phytohormones and other signaling molecules. Dietary carotenoids are vital to human health as a source of provitamin A and antioxidants. Hence, the enormous interest in carotenoids of crop plants. Over the past three decades, the carotenoid biosynthesis pathway has been mainly deciphered due to the characterization of natural and induced mutations that impair this process. Over the year, numerous mutations have been studied in dozens of plant species. Their phenotypes have significantly expanded our understanding of the biochemical and molecular processes underlying carotenoid accumulation in crops. Several of them were employed in the breeding of crops with higher nutritional value. This compendium of all known random and targeted mutants available in the carotenoid metabolic pathway in plants provides a valuable resource for future research on carotenoid biosynthesis in plant species.
Collapse
Affiliation(s)
| | - Joseph Hirschberg
- Department of Genetics, Alexander Silberman Institute of Life Sciences, The Hebrew University of Jerusalem, Jerusalem, Israel
| |
Collapse
|
8
|
Ren Y, He Z, Liu P, Traw B, Sun S, Tian D, Yang S, Jia Y, Wang L. Somatic Mutation Analysis in Salix suchowensis Reveals Early-Segregated Cell Lineages. Mol Biol Evol 2021; 38:5292-5308. [PMID: 34562099 PMCID: PMC8662653 DOI: 10.1093/molbev/msab286] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
Long-lived plants face the challenge of ever-increasing mutational burden across their long lifespan. Early sequestration of meristematic stem cells is supposed to efficiently slow down this process, but direct measurement of somatic mutations that accompanies segregated cell lineages in plants is still rare. Here, we tracked somatic mutations in 33 leaves and 22 adventitious roots from 22 stem-cuttings across eight major branches of a shrub willow (Salix suchowensis). We found that most mutations propagated separately in leaves and roots, providing clear evidence for early segregation of underlying cell lineages. By combining lineage tracking with allele frequency analysis, our results revealed a set of mutations shared by distinct branches, but were exclusively present in leaves and not in roots. These mutations were likely propagated by rapidly dividing somatic cell lineages which survive several iterations of branching, distinct from the slowly dividing axillary stem cell lineages. Leaf is thus contributed by both slowly and rapidly dividing cell lineages, leading to varied fixation chances of propagated mutations. By contrast, each root likely arises from a single founder cell within the adventitious stem cell lineages. Our findings give straightforward evidence that early segregation of meristems slows down mutation accumulation in axillary meristems, implying a plant "germline" paralog to the germline of animals through convergent evolution.
Collapse
Affiliation(s)
- Yifan Ren
- State Key Laboratory of Pharmaceutical Biotechnology, School of Life Sciences, Nanjing University, Nanjing, China
| | - Zhen He
- State Key Laboratory of Pharmaceutical Biotechnology, School of Life Sciences, Nanjing University, Nanjing, China
| | - Pingyu Liu
- State Key Laboratory of Pharmaceutical Biotechnology, School of Life Sciences, Nanjing University, Nanjing, China
| | - Brian Traw
- State Key Laboratory of Pharmaceutical Biotechnology, School of Life Sciences, Nanjing University, Nanjing, China
| | - Shucun Sun
- Department of Ecology, School of Life Science, Nanjing University, Nanjing, China
| | - Dacheng Tian
- State Key Laboratory of Pharmaceutical Biotechnology, School of Life Sciences, Nanjing University, Nanjing, China
| | - Sihai Yang
- State Key Laboratory of Pharmaceutical Biotechnology, School of Life Sciences, Nanjing University, Nanjing, China
| | - Yanxiao Jia
- State Key Laboratory for Crop Genetics and Germplasm Enhancement, Nanjing Agricultural University, Nanjing, China
| | - Long Wang
- State Key Laboratory of Pharmaceutical Biotechnology, School of Life Sciences, Nanjing University, Nanjing, China
| |
Collapse
|
9
|
Sleith RS, Karol KG. Global high-throughput genotyping of organellar genomes reveals insights into the origin and spread of invasive starry stonewort (Nitellopsis obtusa). Biol Invasions 2021. [DOI: 10.1007/s10530-021-02591-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 08/30/2023]
Abstract
AbstractAquatic invasive species are damaging to native ecosystems. Preventing their spread and achieving comprehensive control measures requires an understanding of the genetic structure of an invasive population. Organellar genomes (plastid and mitochondrial) are useful for population level analyses of invasive plant distributions. In this study we generate complete organellar reference genomes using PacBio sequencing, then use these reference sequences for SNP calling of high-throughput, multiplexed, Illumina based organellar sequencing of fresh and historical samples from across the native and invasive range of Nitellopsis obtusa (Desv. in Loisel.) J.Groves, an invasive macroalgae. The data generated by the analytical pipeline we develop indicate introduction to North America from Western Europe. A single nucleotide transversion in the plastid genome separates a group of five samples from Michigan and Wisconsin that either resulted from introductions of two closely related genotypes or a mutation that has arisen in the invasive range. This transversion will serve as a useful tool to understand how Nitellopsis obtusa moves across the landscape. The methods and analyses described here are broadly applicable to invasive and native plant and algae species, and allow efficient genotyping of variable quality samples, including 100-year-old herbarium specimens, to determine population structure and geographic distributions.
Collapse
|
10
|
Harms NE, Thum RA, Gettys LA, Markovich IJ, French A, Simantel L, Richardson R. Hybridization between native and invasive Nymphoides species in the United States. Biol Invasions 2021. [DOI: 10.1007/s10530-021-02558-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
|
11
|
Simón-Porcar VI, Silva JL, Vallejo-Marín M. Rapid local adaptation in both sexual and asexual invasive populations of monkeyflowers (Mimulus spp.). ANNALS OF BOTANY 2021; 127:655-668. [PMID: 33604608 PMCID: PMC8052927 DOI: 10.1093/aob/mcab004] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/22/2020] [Accepted: 01/07/2021] [Indexed: 06/12/2023]
Abstract
BACKGROUND AND AIMS Traditionally, local adaptation has been seen as the outcome of a long evolutionary history, particularly with regard to sexual lineages. By contrast, phenotypic plasticity has been thought to be most important during the initial stages of population establishment and in asexual species. We evaluated the roles of adaptive evolution and phenotypic plasticity in the invasive success of two closely related species of invasive monkeyflowers (Mimulus) in the UK that have contrasting reproductive strategies: M. guttatus combines sexual (seeds) and asexual (clonal growth) reproduction while M. × robertsii is entirely asexual. METHODS We compared the clonality (number of stolons), floral and vegetative phenotype, and phenotypic plasticity of native (M. guttatus) and invasive (M. guttatus and M. × robertsii) populations grown in controlled environment chambers under the environmental conditions at each latitudinal extreme of the UK. The goal was to discern the roles of temperature and photoperiod on the expression of phenotypic traits. Next, we tested the existence of local adaptation in the two species within the invasive range with a reciprocal transplant experiment at two field sites in the latitudinal extremes of the UK, and analysed which phenotypic traits underlie potential local fitness advantages in each species. KEY RESULTS Populations of M. guttatus in the UK showed local adaptation through sexual function (fruit production), while M. × robertsii showed local adaptation via asexual function (stolon production). Phenotypic selection analyses revealed that different traits are associated with fitness in each species. Invasive and native populations of M. guttatus had similar phenotypic plasticity and clonality. M. × robertsii presents greater plasticity and clonality than native M. guttatus, but most populations have restricted clonality under the warm conditions of the south of the UK. CONCLUSIONS This study provides experimental evidence of local adaptation in a strictly asexual invasive species with high clonality and phenotypic plasticity. This indicates that even asexual taxa can rapidly (<200 years) adapt to novel environmental conditions in which alternative strategies may not ensure the persistence of populations.
Collapse
Affiliation(s)
- Violeta I Simón-Porcar
- Departmento de Biología Vegetal y Ecología, Universidad de Sevilla, Apartado 1095, E-41080 Sevilla, Spain
| | - Jose L Silva
- Pyrenean Institute of Ecology (CSIC), Avenida Montañana 1005, 50059 Zaragoza, Spain
| | - Mario Vallejo-Marín
- Biological and Environmental Sciences, Faculty of Natural Sciences, University of Stirling, Stirling, Scotland FK9 4LA, UK
| |
Collapse
|
12
|
Endo M, Iwakami S, Toki S. Precision genome editing in plants via gene targeting and subsequent break-induced single-strand annealing. PLANT BIOTECHNOLOGY JOURNAL 2021; 19:563-574. [PMID: 33001567 PMCID: PMC7955887 DOI: 10.1111/pbi.13485] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/08/2020] [Revised: 08/27/2020] [Accepted: 09/14/2020] [Indexed: 05/29/2023]
Abstract
Genome editing via artificial nucleases such as CRISPR/Cas9 has become popular in plants now. However, small insertions or deletions are major mutations and nucleotide substitutions rarely occur when DNA cleavage is induced. To induce nucleotide substitutions, a base editor utilizing dead or nickase-type Cas9 fused with deaminase have been developed. However, the direction and position of practical substitution are still limited. In this context, homologous recombination (HR)-mediated gene targeting (GT) has advantages because any mutations existing on the donor DNA are copied and passed onto the endogenous DNA. As HR-mediated GT is extremely rare in higher plants, positive-negative selection has been used to isolate cells in which GT has occurred. After successful selection, positive selection marker is no longer needed and should ideally be eliminated. In a previous study, we reported a seamless piggyBac-transposon-mediated marker elimination system. Precision marker elimination efficiency in this system is very high. The piggyBac transposon integrates into the host genome at TTAA elements and excises without leaving a footprint at the excised site, so a TTAA sequence is necessary at the location of a positive selection marker. To compensate for this limitation, we have developed a novel marker elimination system using an I-SceI break and subsequent single-strand annealing (SSA)-mediated DNA repair system.
Collapse
Affiliation(s)
- Masaki Endo
- Plant Genome Engineering Research UnitInstitute of Agrobiological SciencesNational Agriculture and Food Research OrganizationTsukubaJapan
| | | | - Seiichi Toki
- Plant Genome Engineering Research UnitInstitute of Agrobiological SciencesNational Agriculture and Food Research OrganizationTsukubaJapan
- Graduate School of NanobioscienceYokohama City UniversityYokohamaJapan
- Kihara Institute for Biological ResearchYokohama City UniversityYokohamaJapan
| |
Collapse
|
13
|
Lee JY, Park S, Lim W, Song G. Picolinafen exerts developmental toxicity via the suppression of oxidative stress and angiogenesis in zebrafish embryos. PESTICIDE BIOCHEMISTRY AND PHYSIOLOGY 2021; 171:104734. [PMID: 33357556 DOI: 10.1016/j.pestbp.2020.104734] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/18/2020] [Revised: 10/12/2020] [Accepted: 10/13/2020] [Indexed: 06/12/2023]
Abstract
Picolinafen, a phytoene desaturase-inhibiting herbicide, has been used since 2001 to control the growth of broadleaf weeds. Picolinafen has lower solubility and volatility, and shows lower toxicity to non-target insect species than other types of herbicide. Although picolinafen has been detected in lakes near urban environments and induces chronic toxicity in the mammals, birds, and some aquatic organisms, no study has investigated the toxicity or mode of action of picolinafen in zebrafish. In this study, we demonstrated the lethality and acute LC50 value of picolinafen towards zebrafish embryos. Picolinafen hampered the development of embryos by the induction of morphological abnormalities via apoptosis. Additionally, picolinafen suppressed the generation of reactive oxygen species and angiogenesis. Also, the angiogenesis related genes, flt1 and flt4 mRNA expression was decreased in zebrafish embryos. This study provides a mechanistic understanding of the developmental toxicity of picolinafen in vertebrates.
Collapse
Affiliation(s)
- Jin-Young Lee
- Department of Pharmacology and Toxicology, Medical College of Wisconsin, Milwaukee, WI 53226, USA
| | - Sunwoo Park
- Institute of Animal Molecular Biotechnology, Department of Biotechnology, College of Life Sciences and Biotechnology, Korea University, Seoul 02841, Republic of Korea
| | - Whasun Lim
- Department of Food and Nutrition, Kookmin University, Seoul 02707, Republic of Korea.
| | - Gwonhwa Song
- Institute of Animal Molecular Biotechnology, Department of Biotechnology, College of Life Sciences and Biotechnology, Korea University, Seoul 02841, Republic of Korea.
| |
Collapse
|
14
|
Simberloff D. Maintenance management and eradication of established aquatic invaders. HYDROBIOLOGIA 2021; 848:2399-2420. [PMID: 32836349 PMCID: PMC7407435 DOI: 10.1007/s10750-020-04352-5] [Citation(s) in RCA: 21] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/06/2020] [Revised: 07/01/2020] [Accepted: 07/08/2020] [Indexed: 05/04/2023]
Abstract
Although freshwater invasions have not been targeted for maintenance management or eradication as often as terrestrial invasions have, attempts to do so are frequent. Failures as well as successes abound, but several methods have been improved and new approaches are on the horizon. Many freshwater fish and plant invaders have been eliminated, especially by chemical and physical methods for fishes and herbicides for plants. Efforts to maintain invasive freshwater fishes at low levels have sometimes succeeded, although continuing the effort has proven challenging. By contrast, successful maintenance management of invasive freshwater plants is uncommon, although populations of several species have been managed by biological control. Invasive crayfish populations have rarely been controlled for long. Marine invasions have proven far less tractable than those in fresh water, with a few striking eradications of species detected before they had spread widely, and no marine invasions have been substantially managed for long at low levels. The rapid development of technologies based on genetics has engendered excitement about possibly eradicating or controlling terrestrial invaders, and such technologies may also prove useful for certain aquatic invaders. Methods of particular interest, alone or in various combinations, are gene-silencing, RNA-guided gene drives, and the use of transgenes.
Collapse
Affiliation(s)
- Daniel Simberloff
- Department of Ecology and Evolutionary Biology, University of Tennessee, Knoxville, TN 37996 USA
| |
Collapse
|
15
|
Buczek SB, Archambault JM, Gregory Cope W, Heilman MA. Evaluation of Juvenile Freshwater Mussel Sensitivity to Multiple Forms of Florpyrauxifen-Benzyl. BULLETIN OF ENVIRONMENTAL CONTAMINATION AND TOXICOLOGY 2020; 105:588-594. [PMID: 32856147 DOI: 10.1007/s00128-020-02971-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/09/2020] [Accepted: 08/13/2020] [Indexed: 06/11/2023]
Abstract
ProcellaCOR® (active ingredient [ai], florpyrauxifen-benzyl) is an aquatic herbicide registered for use in 2018 for managing invasive and nuisance macrophyte species. Registration studies evaluating its acute toxicity revealed a favorable environmental profile; however, prior to this study, no information existed on the toxicity of florpyrauxifen-benzyl to native freshwater mussels (Family Unionidae), one of the most sensitive and imperiled faunal groups globally. We followed standard acute (96 h) toxicity test guidelines and exposed juvenile Fatmucket (Lampsilis siliquoidea) and Eastern Lampmussel (Lampsilis radiata) to the following formulations or compounds: ProcellaCOR SC and EC formulations, technical grade active ingredient (TGAI, florpyrauxifen-benzyl), and an analytical-grade sample of the weaker florpyrauxifen acid (FA). In all tests, the estimated median lethal concentrations to produce 50% mortality (LC50) were greater than the highest concentration tested of each formulation or compound. The no observable adverse effect concentrations (NOAEC, based on analytical recoveries measured at the highest concentration tested where no toxicity was observed) were TGAI = 26 µg/L, FA = 100,000 µg/L, ProcellaCOR® SC = 193 µg ai/L ProcellaCOR® EC = 585 µg ai/L and the NOAEC values for the registered commercial formulation products (ProcellaCOR® SC and ProcellaCOR® EC) were orders of magnitude greater (3.9× and 11.7×, respectively) than the maximum application rate (50 µg/L). Our results show that the herbicide formulations and compounds tested were not acutely toxic to juveniles of these two species of freshwater mussels, indicating minimal risk of short-term exposure from florpyrauxifen-benzyl applications in the environment for aquatic weed control. However, potential chronic or sublethal effects remain uncharacterized and warrant additional investigation.
Collapse
Affiliation(s)
- Sean B Buczek
- Department of Applied Ecology, North Carolina State University, Campus Box 7617, Raleigh, NC, 27695, USA.
| | - Jennifer M Archambault
- Department of Applied Ecology, North Carolina State University, Campus Box 7617, Raleigh, NC, 27695, USA
| | - W Gregory Cope
- Department of Applied Ecology, North Carolina State University, Campus Box 7617, Raleigh, NC, 27695, USA
| | - Mark A Heilman
- SePRO Corporation, 11550 North Meridian Street, Suite 600, Carmel, IN, 46032, USA
| |
Collapse
|
16
|
Gaines TA, Duke SO, Morran S, Rigon CAG, Tranel PJ, Küpper A, Dayan FE. Mechanisms of evolved herbicide resistance. J Biol Chem 2020; 295:10307-10330. [PMID: 32430396 PMCID: PMC7383398 DOI: 10.1074/jbc.rev120.013572] [Citation(s) in RCA: 193] [Impact Index Per Article: 48.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2020] [Revised: 05/18/2020] [Indexed: 12/13/2022] Open
Abstract
The widely successful use of synthetic herbicides over the past 70 years has imposed strong and widespread selection pressure, leading to the evolution of herbicide resistance in hundreds of weed species. Both target-site resistance (TSR) and nontarget-site resistance (NTSR) mechanisms have evolved to most herbicide classes. TSR often involves mutations in genes encoding the protein targets of herbicides, affecting the binding of the herbicide either at or near catalytic domains or in regions affecting access to them. Most of these mutations are nonsynonymous SNPs, but polymorphisms in more than one codon or entire codon deletions have also evolved. Some herbicides bind multiple proteins, making the evolution of TSR mechanisms more difficult. Increased amounts of protein target, by increased gene expression or by gene duplication, are an important, albeit less common, TSR mechanism. NTSR mechanisms include reduced absorption or translocation and increased sequestration or metabolic degradation. The mechanisms that can contribute to NTSR are complex and often involve genes that are members of large gene families. For example, enzymes involved in herbicide metabolism-based resistances include cytochromes P450, GSH S-transferases, glucosyl and other transferases, aryl acylamidase, and others. Both TSR and NTSR mechanisms can combine at the individual level to produce higher resistance levels. The vast array of herbicide-resistance mechanisms for generalist (NTSR) and specialist (TSR and some NTSR) adaptations that have evolved over a few decades illustrate the evolutionary resilience of weed populations to extreme selection pressures. These evolutionary processes drive herbicide and herbicide-resistant crop development and resistance management strategies.
Collapse
Affiliation(s)
- Todd A Gaines
- Agricultural Biology Department, Colorado State University, Fort Collins, Colorado, USA
| | - Stephen O Duke
- National Center for Natural Products Research, School of Pharmacy, University of Mississippi, Oxford, Mississippi, USA
| | - Sarah Morran
- Agricultural Biology Department, Colorado State University, Fort Collins, Colorado, USA
| | - Carlos A G Rigon
- Agricultural Biology Department, Colorado State University, Fort Collins, Colorado, USA
| | - Patrick J Tranel
- Department of Crop Sciences, University of Illinois, Urbana, Illinois, USA
| | - Anita Küpper
- Bayer AG, CropScience Division, Frankfurt am Main, Germany
| | - Franck E Dayan
- Agricultural Biology Department, Colorado State University, Fort Collins, Colorado, USA
| |
Collapse
|
17
|
Lu H, Yu Q, Han H, Owen MJ, Powles SB. Non-target-site resistance to PDS-inhibiting herbicides in a wild radish (Raphanus raphanistrum) population. PEST MANAGEMENT SCIENCE 2020; 76:2015-2020. [PMID: 31867843 DOI: 10.1002/ps.5733] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/11/2019] [Revised: 12/17/2019] [Accepted: 12/22/2019] [Indexed: 06/10/2023]
Abstract
BACKGROUND Diflufenican resistance has been reported in wild radish populations since 1998, but the resistance mechanisms have not been investigated. Recently, we identified a wild radish population (H2/10) from the Western Australian grain belt that is resistant (R) to the phytoene desaturase (PDS)-inhibiting herbicide diflufenican. RESULTS Dose-response results showed this R population is 4.9-fold more resistant than the susceptible (S) population based on the LD50 R/S ratio. In addition, the R population also exhibits cross-resistance to the PDS-inhibiting herbicide fluridone. The cytochrome P450 inhibitor malathion reversed diflufenican resistance and partially reversed fluridone resistance in the R population. The full coding sequences of the PDS gene were cloned from the S and R plants and there are natural variations in the PDS gene transcripts/alleles with no correlation to resistance. In addition, the R plants had a level of PDS gene expression that is not significantly different from the S plants. CONCLUSION These results demonstrated that diflufenican resistance in this R wild radish population is likely due to non-target-site based enhanced herbicide metabolism involving cytochrome P450s. © 2019 Society of Chemical Industry.
Collapse
Affiliation(s)
- Huan Lu
- Australian Herbicide Resistance Initiative (AHRI), School of Agriculture and Environment, University of Western Australia, Crawley, Western Australia, Australia
| | - Qin Yu
- Australian Herbicide Resistance Initiative (AHRI), School of Agriculture and Environment, University of Western Australia, Crawley, Western Australia, Australia
| | - Heping Han
- Australian Herbicide Resistance Initiative (AHRI), School of Agriculture and Environment, University of Western Australia, Crawley, Western Australia, Australia
| | - Mechelle J Owen
- Australian Herbicide Resistance Initiative (AHRI), School of Agriculture and Environment, University of Western Australia, Crawley, Western Australia, Australia
| | - Stephen B Powles
- Australian Herbicide Resistance Initiative (AHRI), School of Agriculture and Environment, University of Western Australia, Crawley, Western Australia, Australia
| |
Collapse
|
18
|
Ripa RR, Franzese J, Premoli AC, Raffaele E. Increased canopy seed-storage in post-fire pine invaders suggests rapid selection mediated by fire. Basic Appl Ecol 2020. [DOI: 10.1016/j.baae.2020.04.002] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
|
19
|
Orr AJ, Padovan A, Kainer D, Külheim C, Bromham L, Bustos-Segura C, Foley W, Haff T, Hsieh JF, Morales-Suarez A, Cartwright RA, Lanfear R. A phylogenomic approach reveals a low somatic mutation rate in a long-lived plant. Proc Biol Sci 2020; 287:20192364. [PMID: 32156194 PMCID: PMC7126060 DOI: 10.1098/rspb.2019.2364] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023] Open
Abstract
Somatic mutations can have important effects on the life history, ecology, and evolution of plants, but the rate at which they accumulate is poorly understood and difficult to measure directly. Here, we develop a method to measure somatic mutations in individual plants and use it to estimate the somatic mutation rate in a large, long-lived, phenotypically mosaic Eucalyptus melliodora tree. Despite being 100 times larger than Arabidopsis, this tree has a per-generation mutation rate only ten times greater, which suggests that this species may have evolved mechanisms to reduce the mutation rate per unit of growth. This adds to a growing body of evidence that illuminates the correlated evolutionary shifts in mutation rate and life history in plants.
Collapse
Affiliation(s)
- Adam J Orr
- The Biodesign Institute and the School of Life Sciences, Arizona State University, Tempe, AZ, USA
| | - Amanda Padovan
- Division of Ecology and Evolution, Research School of Biology, Australian National University, Canberra, Australia.,CSIRO Black Mountain Science and Innovation Park, Canberra, ACT 2601, Australia
| | - David Kainer
- Division of Ecology and Evolution, Research School of Biology, Australian National University, Canberra, Australia
| | - Carsten Külheim
- Division of Ecology and Evolution, Research School of Biology, Australian National University, Canberra, Australia.,School of Forest Resources and Environmental Science, Michigan Technological University, Houghton, MI 49931, USA
| | - Lindell Bromham
- Division of Ecology and Evolution, Research School of Biology, Australian National University, Canberra, Australia
| | - Carlos Bustos-Segura
- Division of Ecology and Evolution, Research School of Biology, Australian National University, Canberra, Australia
| | - William Foley
- Division of Ecology and Evolution, Research School of Biology, Australian National University, Canberra, Australia
| | - Tonya Haff
- Division of Ecology and Evolution, Research School of Biology, Australian National University, Canberra, Australia
| | - Ji-Fan Hsieh
- Division of Ecology and Evolution, Research School of Biology, Australian National University, Canberra, Australia
| | | | - Reed A Cartwright
- The Biodesign Institute and the School of Life Sciences, Arizona State University, Tempe, AZ, USA
| | - Robert Lanfear
- Division of Ecology and Evolution, Research School of Biology, Australian National University, Canberra, Australia.,Department of Biological Sciences, Macquarie University, Sydney, Australia
| |
Collapse
|
20
|
Abstract
Epigenetic changes influence gene expression and contribute to the modulation of biological processes in response to the environment. Transgenerational epigenetic changes in gene expression have been described in many eukaryotes. However, plants appear to have a stronger propensity for inheriting novel epialleles. This mini-review discusses how plant traits, such as meristematic growth, totipotency, and incomplete epigenetic erasure in gametes promote epiallele inheritance. Additionally, we highlight how plant biology may be inherently tailored to reap the benefits of epigenetic metastability. Importantly, environmentally triggered small RNA expression and subsequent epigenetic changes may allow immobile plants to adapt themselves, and possibly their progeny, to thrive in local environments. The change of epigenetic states through the passage of generations has ramifications for evolution in the natural and agricultural world. In populations containing little genetic diversity, such as elite crop germplasm or habitually self-reproducing species, epigenetics may provide an important source of heritable phenotypic variation. Basic understanding of the processes that direct epigenetic shifts in the genome may allow for breeding or bioengineering for improved plant traits that do not require changes to DNA sequence.
Collapse
Affiliation(s)
- Mark A A Minow
- Department of Molecular and Cellular Biology, University of Guelph, 50 Stone Road East, Guelph, ON N1G 2W1, Canada.,Department of Molecular and Cellular Biology, University of Guelph, 50 Stone Road East, Guelph, ON N1G 2W1, Canada
| | - Joseph Colasanti
- Department of Molecular and Cellular Biology, University of Guelph, 50 Stone Road East, Guelph, ON N1G 2W1, Canada
| |
Collapse
|
21
|
Benoit LK, Les DH, King UM, Na HR, Chen L, Tippery NP. Extensive interlineage hybridization in the predominantly clonal Hydrilla verticillata. AMERICAN JOURNAL OF BOTANY 2019; 106:1622-1637. [PMID: 31758546 DOI: 10.1002/ajb2.1392] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/30/2019] [Accepted: 10/01/2019] [Indexed: 06/10/2023]
Abstract
PREMISE The submersed aquatic plant Hydrilla verticillata ("hydrilla") is important ecologically and economically due to its aggressive growth in both indigenous and nonindigenous regions. Substantial morphological variation has been documented in hydrilla, including the existence of monoecious and dioecious "biotypes." Whereas plastid sequence data have been used previously to explore intraspecific diversity, nuclear data have yet to be analyzed in a phylogenetic context. Molecular and morphological analyses were used to evaluate the genetic diversity and phylogenetic relationships of native and introduced populations. METHODS Nuclear (internal transcribed spacer-ITS; phytoene desaturase-PDS) and plastid (trnL-F) sequence data were evaluated phylogenetically using likelihood and Bayesian methods. Leaf morphologies were compared among clades that were identified in phylogenetic analyses. RESULTS Data from both ITS and PDS show multiple instances of polymorphic sequences that could be traced to two or more lineages, including both invasive biotypes in the Americas. Leaf morphological data support the distinctness of lineages and provide a metric for distinguishing monoecious and dioecious biotypes in the United States. CONCLUSIONS Nuclear molecular data indicate far greater genetic diversity than could be estimated using plastid markers. Substantially divergent copies of nuclear genes, found in multiple populations worldwide, likely result from interlineage hybridization. Invasive monoecious and dioecious hydrilla biotypes in the Americas are genetically distinct, with both biotypes resulting from admixture among Eurasian progenitors. Genetic similarity to populations in India and South Korea, respectively, implicates these as likely origins for the dioecious and monoecious biotypes.
Collapse
Affiliation(s)
- Lori K Benoit
- Department of Ecology and Evolutionary Biology, University of Connecticut, Storrs, Connecticut, 06269-3043, USA
| | - Donald H Les
- Department of Ecology and Evolutionary Biology, University of Connecticut, Storrs, Connecticut, 06269-3043, USA
| | - Ursula M King
- Department of Ecology and Evolutionary Biology, University of Connecticut, Storrs, Connecticut, 06269-3043, USA
| | - Hye Ryun Na
- Northeastern Asia Biodiversity Institute, Seoul, 05677, Republic of Korea
| | - Lei Chen
- South China Botanical Garden, Chinese Academy of Sciences, Guangzhou, 510650, China
| | - Nicholas P Tippery
- Department of Biological Sciences, University of Wisconsin-Whitewater, Whitewater, Wisconsin, 53190, USA
| |
Collapse
|
22
|
Schoen DJ, Schultz ST. Somatic Mutation and Evolution in Plants. ANNUAL REVIEW OF ECOLOGY EVOLUTION AND SYSTEMATICS 2019. [DOI: 10.1146/annurev-ecolsys-110218-024955] [Citation(s) in RCA: 43] [Impact Index Per Article: 8.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Somatic mutations are common in plants, and they may accumulate and be passed on to gametes. The determinants of somatic mutation accumulation include the intraorganismal selective effect of mutations, the number of cell divisions that separate the zygote from the formation of gametes, and shoot apical meristem structure and branching. Somatic mutations can promote the evolution of diploidy, polyploidy, sexual recombination, outcrossing, clonality, and separate sexes, and they may contribute genetic variability in many other traits. The amplification of beneficial mutations via intraorganismal selection may relax selection to reduce the genomic mutation rate or to protect the germline in plants. The total rate of somatic mutation, the distribution of selective effects and fates in the plant body, and the degree to which the germline is sheltered from somatic mutations are still poorly understood. Our knowledge can be improved through empirical estimates of mutation rates and effects on cell lineages and whole organisms, such as estimates of the reduction in fitness of progeny produced by within- versus between-flower crosses on the same plant, mutation coalescent studies within the canopy, and incorporation of somatic mutation into theoretical models of plant evolutionary genetics.
Collapse
Affiliation(s)
- Daniel J. Schoen
- Department of Biology, McGill University, Montreal, Quebec H3A 1B1, Canada
| | - Stewart T. Schultz
- Department of Ecology, Agronomy, and Aquaculture, University of Zadar, 23000 Zadar, Croatia
| |
Collapse
|
23
|
Ortiz MF, Nissen SJ, Gray CJ. Endothall behavior in Myriophyllum spicatum and Hydrilla verticillata. PEST MANAGEMENT SCIENCE 2019; 75:2942-2947. [PMID: 30854787 DOI: 10.1002/ps.5404] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/11/2018] [Revised: 03/07/2019] [Accepted: 03/08/2019] [Indexed: 06/09/2023]
Abstract
BACKGROUND Endothall has been used to control submersed aquatic plants since 1960, providing broad-spectrum control of aquatic weeds. Although endothall is considered a contact herbicide, many field observations suggest that it might have systemic activity. The goals of this research were to determine endothall's (i) absorption characteristics, (ii) translocation from shoots to roots, and (iii) potential for desorption in Eurasian watermilfoil (EWM), monoecious and dioecious hydrilla. RESULTS Endothall absorption was linear in dioecious hydrilla up to 192 HAT, while in EWM and monoecious hydrilla absorption data best fit an asymptotic rise function. Endothall absorption in EWM, monoecious and dioecious hydrilla was 3.3, 6.6, and 11.0 times the external herbicide concentration determined by the plant concentration factor. Translocation to EWM roots reached 7.9% of total absorbed radioactivity by 192 HAT, while translocation to monoecious and dioecious hydrilla roots reached 17.8% and 16.4% by 192 HAT, respectively. For all three species, no more than 30% of absorbed endothall moved from the plant to clean water 96 HAT. CONCLUSION Endothall is a very water soluble compound and yet it accumulated in these three important aquatic weeds at concentrations significantly higher than the external herbicide concentration. These data provide evidence that endothall could have systemic activity in these aquatic species. Following 14 C-endothall applications, more 14 C translocated from shoots to roots compared to the translocation of 14 C for other systemic aquatic herbicides. The final confirmation of endothall's systemic behavior requires that the radioactivity found in the root system of these aquatic plants is 14 C endothall. © 2019 Society of Chemical Industry.
Collapse
Affiliation(s)
- Mirella F Ortiz
- Department of Bioagricultural Sciences and Pest Management, Colorado State University, Fort Collins, CO, USA
| | - Scott J Nissen
- Department of Bioagricultural Sciences and Pest Management, Colorado State University, Fort Collins, CO, USA
| | | |
Collapse
|
24
|
Lam CH, Kurobe T, Lehman PW, Berg M, Hammock BG, Stillway ME, Pandey PK, Teh SJ. Toxicity of herbicides to cyanobacteria and phytoplankton species of the San Francisco Estuary and Sacramento-San Joaquin River Delta, California, USA. JOURNAL OF ENVIRONMENTAL SCIENCE AND HEALTH. PART A, TOXIC/HAZARDOUS SUBSTANCES & ENVIRONMENTAL ENGINEERING 2019; 55:107-118. [PMID: 31642727 DOI: 10.1080/10934529.2019.1672458] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/23/2019] [Revised: 09/17/2019] [Accepted: 09/20/2019] [Indexed: 06/10/2023]
Abstract
The herbicides glyphosate, imazamox and fluridone are herbicides, with low toxicity towards fish and invertebrates, which are applied to waterways to control invasive aquatic weeds. However, the effects of these herbicides on natural isolates of phytoplankton and cyanobacteria are unknown. Three species of microalgae found in the San Francisco Estuary (SFE)/Sacramento-San Joaquin River Delta (Delta) (Microcystis aeruginosa, Chlamydomonas debaryana, and Thalassiosira pseudonana) were exposed to the three herbicides at a range of concentrations in 96-well plates for 5-8 days. All three algal species were the most sensitive to fluridone, with IC50 of 46.9, 21, and 109 µg L-1 for M. aeruginosa, T. pseudonana and C. debaryana, respectively. Imazamox inhibited M. aeruginosa and T. pseudonana growth at 3.6 × 104 µg L-1 or higher, and inhibited C. debaryana growth at 1.0 × 105 µg L-1 or higher. Glyphosate inhibited growth in all species at ca. 7.0 × 104 µg L-1 or higher. Fluridone was the only herbicide that inhibited the microalgae at environmentally relevant concentrations in this study and susceptibility to the herbicide depended on the species. Thus, the application of fluridone may affect cyanobacteria and phytoplankton community composition in water bodies where it is applied.
Collapse
Affiliation(s)
- Chelsea H Lam
- Aquatic Health Program, Department of Anatomy, Physiology and Cell Biology, University of California, Davis, Davis, California, USA
| | - Tomofumi Kurobe
- Aquatic Health Program, Department of Anatomy, Physiology and Cell Biology, University of California, Davis, Davis, California, USA
| | - Peggy W Lehman
- California Department of Water Resources, Division of Environmental Services, Special Studies Section, West Sacramento, California, USA
| | - Mine Berg
- Applied Marine Sciences, Santa Cruz, California, USA
| | - Bruce G Hammock
- Aquatic Health Program, Department of Anatomy, Physiology and Cell Biology, University of California, Davis, Davis, California, USA
| | - Marie E Stillway
- Aquatic Health Program, Department of Anatomy, Physiology and Cell Biology, University of California, Davis, Davis, California, USA
| | - Pramod K Pandey
- Department of Population Health and Reproduction, University of California, Davis, Davis, California, USA
| | - Swee J Teh
- Aquatic Health Program, Department of Anatomy, Physiology and Cell Biology, University of California, Davis, Davis, California, USA
| |
Collapse
|
25
|
Why are tall-statured energy grasses of polyploid species complexes potentially invasive? A review of their genetic variation patterns and evolutionary plasticity. Biol Invasions 2019. [DOI: 10.1007/s10530-019-02053-2] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023]
|
26
|
Murphy BP, Tranel PJ. Target-Site Mutations Conferring Herbicide Resistance. PLANTS 2019; 8:plants8100382. [PMID: 31569336 PMCID: PMC6843678 DOI: 10.3390/plants8100382] [Citation(s) in RCA: 43] [Impact Index Per Article: 8.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Received: 09/04/2019] [Revised: 09/25/2019] [Accepted: 09/26/2019] [Indexed: 12/01/2022]
Abstract
Mutations conferring evolved herbicide resistance in weeds are known in nine different herbicide sites of action. This review summarizes recently reported resistance-conferring mutations for each of these nine target sites. One emerging trend is an increase in reports of multiple mutations, including multiple amino acid changes at the glyphosate target site, as well as mutations involving two nucleotide changes at a single amino acid codon. Standard reference sequences are suggested for target sites for which standards do not already exist. We also discuss experimental approaches for investigating cross-resistance patterns and for investigating fitness costs of specific target-site mutations.
Collapse
Affiliation(s)
- Brent P Murphy
- Department of Crop Sciences, University of Illinois, Urbana, IL 61801, USA.
| | - Patrick J Tranel
- Department of Crop Sciences, University of Illinois, Urbana, IL 61801, USA.
| |
Collapse
|
27
|
Taparia Y, Zarka A, Leu S, Zarivach R, Boussiba S, Khozin-Goldberg I. A novel endogenous selection marker for the diatom Phaeodactylum tricornutum based on a unique mutation in phytoene desaturase 1. Sci Rep 2019; 9:8217. [PMID: 31160749 PMCID: PMC6546710 DOI: 10.1038/s41598-019-44710-5] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/19/2018] [Accepted: 05/21/2019] [Indexed: 01/10/2023] Open
Abstract
Phaeodactylum tricornutum is a well-developed model diatom for both marine ecology and microalgal biotechnology, which has been enabled by the sequenced genome and the availability of gene delivery tools, such as biolistic transformation and E. coli-mediated conjugation. Till now, these tools have mainly relied on two selectable markers of bacterial origin which confer resistance to antibiotics Zeocin and nourseothricin. An alternative cost-effective and preferably endogenous selectable marker would facilitate gene stacking efforts through successive transformation or conjugation. We performed UV-mutagenesis of P. tricornutum to obtain mutations in the phytoene desaturase (PDS) gene, conferring resistance to the bleaching herbicide norflurazon. Two mutants displaying high tolerance to norflurazon and carrying unique mutations in PtPDS1 (PHATRDRAFT_45735) were selected. These mutants revealed novel point mutations at a conserved residue Gly290 to Ser/Arg. Homology-based structural modeling of mutated PDS1, over a resolved crystallographic model of rice PDS1 complexed with norflurazon, suggests steric hindrance by bulkier residue substitution may confer herbicide resistance. We report the characterization of PtPDS1 mutants and the development of the first endogenous selectable marker in diatoms suitable for industrial strain development, with the added benefit of biocontainment. The plasmid carrying the mutated PDS1 as a selection marker and eGFP as a reporter was created. An optimized biolistic transformation system is reported which allowed the isolation of positive transgenic events at the rate of 96.7%. Additionally, the ease of in vivo UV-mutagenesis may be employed as a strategy to create PDS-norflurazon-based selectable markers for other diatoms.
Collapse
Affiliation(s)
- Yogesh Taparia
- Microalgal Biotechnology Laboratory, French Associates Institute for Agriculture & Biotechnology of Drylands, The Jacob Blaustein Institutes for Desert Research, Ben-Gurion University of the Negev, Sede-Boqer Campus, Midreshet Ben-Gurion, 8499000, Israel
| | - Aliza Zarka
- Microalgal Biotechnology Laboratory, French Associates Institute for Agriculture & Biotechnology of Drylands, The Jacob Blaustein Institutes for Desert Research, Ben-Gurion University of the Negev, Sede-Boqer Campus, Midreshet Ben-Gurion, 8499000, Israel
| | - Stefan Leu
- Microalgal Biotechnology Laboratory, French Associates Institute for Agriculture & Biotechnology of Drylands, The Jacob Blaustein Institutes for Desert Research, Ben-Gurion University of the Negev, Sede-Boqer Campus, Midreshet Ben-Gurion, 8499000, Israel
| | - Raz Zarivach
- Department of Life Sciences, Faculty of Natural Sciences, Ben-Gurion University of the Negev, Beer-Sheva, 8410501, Israel
| | - Sammy Boussiba
- Microalgal Biotechnology Laboratory, French Associates Institute for Agriculture & Biotechnology of Drylands, The Jacob Blaustein Institutes for Desert Research, Ben-Gurion University of the Negev, Sede-Boqer Campus, Midreshet Ben-Gurion, 8499000, Israel
| | - Inna Khozin-Goldberg
- Microalgal Biotechnology Laboratory, French Associates Institute for Agriculture & Biotechnology of Drylands, The Jacob Blaustein Institutes for Desert Research, Ben-Gurion University of the Negev, Sede-Boqer Campus, Midreshet Ben-Gurion, 8499000, Israel.
| |
Collapse
|
28
|
Molina-Márquez A, Vila M, Vigara J, Borrero A, León R. The Bacterial Phytoene Desaturase-Encoding Gene ( CRTI) is an Efficient Selectable Marker for the Genetic Transformation of Eukaryotic Microalgae. Metabolites 2019; 9:E49. [PMID: 30871061 PMCID: PMC6468381 DOI: 10.3390/metabo9030049] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2019] [Revised: 02/27/2019] [Accepted: 03/05/2019] [Indexed: 12/22/2022] Open
Abstract
Genetic manipulation shows great promise to further boost the productivity of microalgae-based compounds. However, selection of microalgal transformants depends mainly on the use of antibiotics, which have raised concerns about their potential impacts on human health and the environment. We propose the use of a synthetic phytoene desaturase-encoding gene (CRTIop) as a selectable marker and the bleaching herbicide norflurazon as a selective agent for the genetic transformation of microalgae. Bacterial phytoene desaturase (CRTI), which, unlike plant and algae phytoene desaturase (PDS), is not sensitive to norflurazon, catalyzes the conversion of the colorless carotenoid phytoene into lycopene. Although the expression of CRTI has been described to increase the carotenoid content in plant cells, its use as a selectable marker has never been testedin algae or in plants. In this study, a version of the CRTI gene adapted to the codon usage of Chlamydomonas has been synthesized, and its suitability to be used as selectable marker has been shown. The microalgae were transformed by the glass bead agitation method and selected in the presence of norflurazon. Average transformation efficiencies of 550 colonies µg-1 DNA were obtained. All the transformants tested had incorporated the CRTIop gene in their genomes and were able to synthesize colored carotenoids.
Collapse
Affiliation(s)
- Ana Molina-Márquez
- Laboratory of Biochemistry, Faculty of Experimental Sciences, Marine International Campus of Excellence (CEIMAR), University of Huelva, 2110 Huelva, Spain.
| | - Marta Vila
- Laboratory of Biochemistry, Faculty of Experimental Sciences, Marine International Campus of Excellence (CEIMAR), University of Huelva, 2110 Huelva, Spain.
- PhycoGenetics SL, C/Joan Miró Nº6, Aljaraque, 21110 Huelva, Spain.
| | - Javier Vigara
- Laboratory of Biochemistry, Faculty of Experimental Sciences, Marine International Campus of Excellence (CEIMAR), University of Huelva, 2110 Huelva, Spain.
| | - Ana Borrero
- Laboratory of Biochemistry, Faculty of Experimental Sciences, Marine International Campus of Excellence (CEIMAR), University of Huelva, 2110 Huelva, Spain.
| | - Rosa León
- Laboratory of Biochemistry, Faculty of Experimental Sciences, Marine International Campus of Excellence (CEIMAR), University of Huelva, 2110 Huelva, Spain.
| |
Collapse
|
29
|
Bai S, Zhang F, Li Z, Wang H, Wang Q, Wang J, Liu W, Bai L. Target-site and non-target-site-based resistance to tribenuron-methyl in multiply-resistant Myosoton aquaticum L. PESTICIDE BIOCHEMISTRY AND PHYSIOLOGY 2019; 155:8-14. [PMID: 30857630 DOI: 10.1016/j.pestbp.2018.12.004] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/09/2018] [Revised: 12/06/2018] [Accepted: 12/13/2018] [Indexed: 06/09/2023]
Abstract
Myosoton aquaticum L., a widespread and competitive winter weed of wheat in China, has evolved resistance to many classes of herbicides. In one M. aquaticum population (AH03), collected from Anhui Province, where tribenuron-methyl and florasulam had been used to control this weed resistance to both herbicides had evolved. Compared with the sensitive population, HN03(S), the resistant (R) population, AH03, was highly resistant to tribenuron-methyl, flucarbazone-Na and pyroxsulam, moderately resistant to pyrithiobac‑sodium, and florasulam, and had low resistance to diflufenican. AH03 was still controlled by imazethapyr, 2,4-D butylate, fluroxypyr-meptyl, and isoproturon. Pretreatment with the P450 inhibitor malathion reduced the GR50 value of tribenuron-methyl by 43% in the R population, and by 25% in the S population. This indicates that P450-mediated enhanced metabolism is one likely mechanism for tribenuron-methyl resistance in M. aquaticum. Glutathione-S-transferase (GST) activity could be induced by tribenuron-methyl in both the R and S populations. However, both the basal and induced GST activity of the R population was lower than that of the S population. The in vitro ALS assay confirmed that the ALS from the R plants showed a high resistance (52.93-fold) to tribenuron-methyl. ALS gene sequencing revealed a Pro197Ala substitution in the R plants. Based on the ALS gene sequence analysis, molecular markers were also developed to identify the specific Pro197Ala mutation. This population of M. aquaticum has multiple resistance and target-site (ALS Pro197Ala) and non-target-site resistance mechanisms contribute to tribenuron-methyl resistance.
Collapse
Affiliation(s)
- Shuang Bai
- College of Plant Protection, Shandong Agricultural University, Tai'an 271018, Shandong, China; Key Laboratory of Pesticide Toxicology and Application Technique, College of Plant Protection, Shandong Agricultural University, Tai'an 271018, Shandong, China
| | - Fengwen Zhang
- College of Plant Protection, Shandong Agricultural University, Tai'an 271018, Shandong, China; Key Laboratory of Pesticide Toxicology and Application Technique, College of Plant Protection, Shandong Agricultural University, Tai'an 271018, Shandong, China
| | - Zuren Li
- Hunan Provincial Key Laboratory for Biology and Control of Weed, Changsha, Hunan 410125, China
| | - Hengzhi Wang
- College of Plant Protection, Shandong Agricultural University, Tai'an 271018, Shandong, China; Key Laboratory of Pesticide Toxicology and Application Technique, College of Plant Protection, Shandong Agricultural University, Tai'an 271018, Shandong, China
| | - Qian Wang
- College of Plant Protection, Shandong Agricultural University, Tai'an 271018, Shandong, China; Key Laboratory of Pesticide Toxicology and Application Technique, College of Plant Protection, Shandong Agricultural University, Tai'an 271018, Shandong, China
| | - Jinxin Wang
- College of Plant Protection, Shandong Agricultural University, Tai'an 271018, Shandong, China; Key Laboratory of Pesticide Toxicology and Application Technique, College of Plant Protection, Shandong Agricultural University, Tai'an 271018, Shandong, China
| | - Weitang Liu
- College of Plant Protection, Shandong Agricultural University, Tai'an 271018, Shandong, China; Key Laboratory of Pesticide Toxicology and Application Technique, College of Plant Protection, Shandong Agricultural University, Tai'an 271018, Shandong, China.
| | - Lianyang Bai
- Hunan Provincial Key Laboratory for Biology and Control of Weed, Changsha, Hunan 410125, China.
| |
Collapse
|
30
|
Dang HT, Long W, Malone JM, Preston C, Gill G. No apparent fitness costs associated with phytoene desaturase mutations conferred resistance to diflufenican and picolinafen in oriental mustard (Sisymbrium orientale L.). PESTICIDE BIOCHEMISTRY AND PHYSIOLOGY 2019; 155:51-57. [PMID: 30857627 DOI: 10.1016/j.pestbp.2019.01.005] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/09/2018] [Revised: 12/05/2018] [Accepted: 01/15/2019] [Indexed: 06/09/2023]
Abstract
Two mutations Leu498 and Glu425 in the PDS gene were identified as the main cause conferring resistance to diflufenican and picolinafen in two oriental mustard populations P3 and P40. As mutations are suspected to affect fitness, this study was designed to test this hypothesis using the F2 of two crosses P3.2 (P3♂ × S♀) and P40.5 (P40♂ × S♀) of oriental mustard. The F2 plants, which segregated for target-site point mutations of PDS gene (Leu498 and Glu425) grown in monoculture and under competition with wheat in pot-trials and evaluated for growth and fecundity. All F2 individuals were genotyped by using Cleaved Amplified Polymorphic Sequence (CAPS) technique. Regression analysis showed no fitness cost in the resistant plants because no significant difference was identified in seed and biomass production within RR, RS and SS individuals. The absence of measurable negative effects on fitness associated mutations suggests that the frequency of the PDS resistance alleles will not decline in the absence of selection pressure of PDS-inhibitors.
Collapse
Affiliation(s)
- Hue Thi Dang
- School of Agriculture, Food and Wine, University of Adelaide, PMB1, Glen Osmond, South Australia 5064, Australia.
| | - Weihua Long
- Institute of the Industrial Crops, Jiangsu Academy of Agriculture Sciences, Nanjing 210014, China
| | - Jenna Moira Malone
- School of Agriculture, Food and Wine, University of Adelaide, PMB1, Glen Osmond, South Australia 5064, Australia
| | - Christopher Preston
- School of Agriculture, Food and Wine, University of Adelaide, PMB1, Glen Osmond, South Australia 5064, Australia
| | - Gurjeet Gill
- School of Agriculture, Food and Wine, University of Adelaide, PMB1, Glen Osmond, South Australia 5064, Australia
| |
Collapse
|
31
|
Simberloff D, Leppanen C. Plant somatic mutations in nature conferring insect and herbicide resistance. PEST MANAGEMENT SCIENCE 2019; 75:14-17. [PMID: 30066358 DOI: 10.1002/ps.5157] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/14/2018] [Revised: 07/27/2018] [Accepted: 07/28/2018] [Indexed: 05/21/2023]
Abstract
Because of the role of the meristem in plant growth and reproduction, somatic mutations in plants have long been suspected of conferring herbivore and pathogen resistance on individual plants and, in the case of trees, individual branches within single plants. A few instances of resistance to phytophagous insects owing to somatic mutations have been reported in the literature. More recently, a striking example has demonstrated how somatic mutations confer resistance to an herbicide on an invasive plant, Hydrilla verticillata. The array of new methods for manipulating genomes (e.g., gene-editing) plus existing examples of somatic mutation-associated resistance suggest that such mutations might be useful in silviculture, agriculture, and horticulture. Answering several general questions about somatic mutations in plants would facilitate such applications: Why are so few examples reported? Do other cases exist but go undetected for want of adequate attention or methods? Under what circumstances do somatic mutations enter gametophytes? © 2018 Society of Chemical Industry.
Collapse
Affiliation(s)
- Daniel Simberloff
- Department of Ecology and Evolutionary Biology, University of Tennessee, Knoxville, TN, USA
| | - Christy Leppanen
- Department of Ecology and Evolutionary Biology, University of Tennessee, Knoxville, TN, USA
| |
Collapse
|
32
|
Dang HT, Malone JM, Gill G, Preston C. Cross-resistance to diflufenican and picolinafen and its inheritance in oriental mustard (Sisymbrium orientale L.). PEST MANAGEMENT SCIENCE 2019; 75:195-203. [PMID: 29799165 DOI: 10.1002/ps.5087] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/19/2018] [Revised: 05/05/2018] [Accepted: 05/18/2018] [Indexed: 06/08/2023]
Abstract
BACKGROUND An oriental mustard population (P40) was identified as resistant to diflufenican by screening at the field rate. As diflufenican and picolinafen both target phytoene desaturase (PDS), cross-resistance to picolinafen was suspected. The mechanism of resistance and its inheritance to diflufenican and picolinafen were investigated. RESULTS At the lethal dose (LD50 ) level, population P40 was 237-fold more resistant to diflufenican and seven-fold more resistant to picolinafen compared to two susceptible populations. Population P40 also had a significantly higher resistance to diflufenican (237-fold) than a previously described P3 population (143-fold). In addition to the Leu-498-Val mutation in PDS identified in all individuals of the P3 and P40 populations, a Glu-425-Asp mutation was also found in P40. Neither mutation was detected in any individuals of the susceptible population. As the segregation of phenotype and genotype of the F2 individuals fitted the model for a single dominant allele, resistance to both diflufenican and picolinafen is likely encoded on the nuclear genome and is dominant. CONCLUSION Resistance to diflufenican and picolinafen in the P40 population is likely conferred by Leu-498-Val and Glu-425-Asp mutations in the PDS gene. Inheritance of resistance to these herbicides is managed by a single dominant gene. © 2018 Society of Chemical Industry.
Collapse
Affiliation(s)
- Hue T Dang
- School of Agriculture, Food and Wine, University of Adelaide, Glen Osmond, Australia
| | - Jenna M Malone
- School of Agriculture, Food and Wine, University of Adelaide, Glen Osmond, Australia
| | - Gurjeet Gill
- School of Agriculture, Food and Wine, University of Adelaide, Glen Osmond, Australia
| | - Christopher Preston
- School of Agriculture, Food and Wine, University of Adelaide, Glen Osmond, Australia
| |
Collapse
|
33
|
Abstract
The keystone species concept is used in ecology to describe individual species with disproportionately large effects on their communities. We extend this idea to the level of genes with disproportionately large effects on ecological processes. Such 'keystone genes' (KGs) would underlie traits involved in species interactions or causing critical biotic and/or abiotic changes that influence emergent community and ecosystem properties. We propose a general framework for how KGs could be identified, while keeping KGs under the umbrella of 'ecologically important genes' (EIGs) that also include categories such as 'foundation genes', 'ecosystem engineering genes', and more. Although likely rare, KGs and other EIGs could dominate certain ecological processes; thus, their discovery and study are relevant for understanding eco-evolutionary dynamics.
Collapse
|
34
|
Dang HT, Malone JM, Boutsalis P, Gill G, Preston C. The mechanism of diflufenican resistance and its inheritance in oriental mustard (Sisymbrium orientale L.) from Australia. PEST MANAGEMENT SCIENCE 2018; 74:1279-1285. [PMID: 29330913 DOI: 10.1002/ps.4858] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/09/2017] [Revised: 12/22/2017] [Accepted: 01/09/2018] [Indexed: 05/28/2023]
Abstract
BACKGROUND An oriental mustard population (P3) collected near Quambatook, Victoria was identified as being resistant to diflufenican by screening with the field rate (200 g a.i. ha-1 ) of the herbicide. The mechanism(s) of diflufenican resistance and its inheritance in this population were therefore investigated. RESULTS Dose-response experiments confirmed that population P3 was 140-fold more resistant to diflufenican than susceptible populations, as determined by the comparison of 50% lethal (LD50 ) values. The phytoene desaturase (PDS) gene from five individuals each of the S1 [susceptible (S)] and P3 [resistant (R)] populations was sequenced, and a substitution of valine for leucine at position 526 (Leu-526-Val) was detected in all five individuals of P3, but not in the S1 population. Inheritance studies showed that diflufenican resistance is encoded in the nuclear genome and is dominant, as the response to diflufenican at 200 g a.i. ha-1 of F1 families was equivalent to that of the resistant biotype. The segregation of F2 phenotypes fitted a 3:1 inheritance model. Segregation of 42 F2 individuals by genotype sequencing fitted a 1:2:1 (ss:Rs:RR) ratio. CONCLUSION Resistance to diflufenican in oriental mustard is conferred by the Leu-526-Val mutation in the PDS gene. Inheritance of resistance is managed by a single gene with high levels of dominance. © 2018 Society of Chemical Industry.
Collapse
Affiliation(s)
- Hue Thi Dang
- School of Agriculture, Food and Wine, University of Adelaide, PMB1, Glen Osmond, South Australia, Australia
| | - Jenna Moira Malone
- School of Agriculture, Food and Wine, University of Adelaide, PMB1, Glen Osmond, South Australia, Australia
| | - Peter Boutsalis
- School of Agriculture, Food and Wine, University of Adelaide, PMB1, Glen Osmond, South Australia, Australia
| | - Gurjeet Gill
- School of Agriculture, Food and Wine, University of Adelaide, PMB1, Glen Osmond, South Australia, Australia
| | - Christopher Preston
- School of Agriculture, Food and Wine, University of Adelaide, PMB1, Glen Osmond, South Australia, Australia
| |
Collapse
|
35
|
Jain MS, Kalamdhad AS. A review on management of Hydrilla verticillata and its utilization as potential nitrogen-rich biomass for compost or biogas production. ACTA ACUST UNITED AC 2018. [DOI: 10.1016/j.biteb.2018.03.001] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/17/2022]
|
36
|
Brausemann A, Gemmecker S, Koschmieder J, Ghisla S, Beyer P, Einsle O. Structure of Phytoene Desaturase Provides Insights into Herbicide Binding and Reaction Mechanisms Involved in Carotene Desaturation. Structure 2017; 25:1222-1232.e3. [PMID: 28669634 DOI: 10.1016/j.str.2017.06.002] [Citation(s) in RCA: 35] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2017] [Revised: 05/10/2017] [Accepted: 06/01/2017] [Indexed: 11/16/2022]
Abstract
Cyanobacteria and plants synthesize carotenoids via a poly-cis pathway starting with phytoene, a membrane-bound C40 hydrocarbon. Phytoene desaturase (PDS) introduces two double bonds and concomitantly isomerizes two neighboring double bonds from trans to cis. PDS assembles into homo-tetramers that interact monotopically with membranes. A long hydrophobic tunnel is proposed to function in the sequential binding of phytoene and the electron acceptor plastoquinone. The herbicidal inhibitor norflurazon binds at a plastoquinone site thereby blocking reoxidation of FADred. Comparison with the sequence-dissimilar bacterial carotene desaturase CRTI reveals substantial similarities in the overall protein fold, defining both as members of the GR2 family of flavoproteins. However, the PDS active center architecture is unprecedented: no functional groups are found in the immediate flavin vicinity that might participate in dehydrogenation and isomerization. This suggests that the isoalloxazine moiety is sufficient for catalysis. Despite mechanistic differences, an ancient evolutionary relation of PDS and CRTI is apparent.
Collapse
Affiliation(s)
- Anton Brausemann
- Institute for Biochemistry, Albert-Ludwigs-Universität Freiburg, Albertstrasse 21, 79104 Freiburg, Germany
| | - Sandra Gemmecker
- Faculty of Biology, Albert-Ludwigs Universität Freiburg, Schänzlestrasse 1, 79104 Freiburg, Germany
| | - Julian Koschmieder
- Faculty of Biology, Albert-Ludwigs Universität Freiburg, Schänzlestrasse 1, 79104 Freiburg, Germany
| | - Sandro Ghisla
- Department of Biology, University of Konstanz, 78457 Konstanz, Germany
| | - Peter Beyer
- Faculty of Biology, Albert-Ludwigs Universität Freiburg, Schänzlestrasse 1, 79104 Freiburg, Germany; BIOSS Centre for Biological Signaling Studies, Schänzlestrasse 1, 79104 Freiburg, Germany.
| | - Oliver Einsle
- Institute for Biochemistry, Albert-Ludwigs-Universität Freiburg, Albertstrasse 21, 79104 Freiburg, Germany; BIOSS Centre for Biological Signaling Studies, Schänzlestrasse 1, 79104 Freiburg, Germany.
| |
Collapse
|
37
|
Chiddarwar RK, Rohrer SG, Wolf A, Tresch S, Wollenhaupt S, Bender A. In silico target prediction for elucidating the mode of action of herbicides including prospective validation. J Mol Graph Model 2016; 71:70-79. [PMID: 27846423 DOI: 10.1016/j.jmgm.2016.10.021] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/27/2016] [Accepted: 10/25/2016] [Indexed: 01/04/2023]
Abstract
The rapid emergence of pesticide resistance has given rise to a demand for herbicides with new mode of action (MoA). In the agrochemical sector, with the availability of experimental high throughput screening (HTS) data, it is now possible to utilize in silico target prediction methods in the early discovery phase to suggest the MoA of a compound via data mining of bioactivity data. While having been established in the pharmaceutical context, in the agrochemical area this approach poses rather different challenges, as we have found in this work, partially due to different chemistry, but even more so due to different (usually smaller) amounts of data, and different ways of conducting HTS. With the aim to apply computational methods for facilitating herbicide target identification, 48,000 bioactivity data against 16 herbicide targets were processed to train Laplacian modified Naïve Bayesian (NB) classification models. The herbicide target prediction model ("HerbiMod") is an ensemble of 16 binary classification models which are evaluated by internal, external and prospective validation sets. In addition to the experimental inactives, 10,000 random agrochemical inactives were included in the training process, which showed to improve the overall balanced accuracy of our models up to 40%. For all the models, performance in terms of balanced accuracy of≥80% was achieved in five-fold cross validation. Ranking target predictions was addressed by means of z-scores which improved predictivity over using raw scores alone. An external testset of 247 compounds from ChEMBL and a prospective testset of 394 compounds from BASF SE tested against five well studied herbicide targets (ACC, ALS, HPPD, PDS and PROTOX) were used for further validation. Only 4% of the compounds in the external testset lied in the applicability domain and extrapolation (and correct prediction) was hence impossible, which on one hand was surprising, and on the other hand illustrated the utilization of using applicability domains in the first place. However, performance better than 60% in balanced accuracy was achieved on the prospective testset, where all the compounds fell within the applicability domain, and which hence underlines the possibility of using target prediction also in the area of agrochemicals.
Collapse
Affiliation(s)
- Rucha K Chiddarwar
- Centre for Molecular Science Informatics, Department of Chemistry, University of Cambridge, Lensfield Road, Cambridge CB2 1EW, United Kingdom
| | - Sebastian G Rohrer
- Global Research Crop Protection, BASF SE, Speyerer Strasse 2, 67177 Limburgerhof, Germany
| | - Antje Wolf
- Computational Chemistry and Biology, BASF SE, Carl-Bosch-Strasse 38, 67056 Ludwigshafen, Germany
| | - Stefan Tresch
- Global Research Crop Protection, BASF SE, Speyerer Strasse 2, 67177 Limburgerhof, Germany
| | - Sabrina Wollenhaupt
- Computational Chemistry and Biology, BASF SE, Carl-Bosch-Strasse 38, 67056 Ludwigshafen, Germany
| | - Andreas Bender
- Centre for Molecular Science Informatics, Department of Chemistry, University of Cambridge, Lensfield Road, Cambridge CB2 1EW, United Kingdom.
| |
Collapse
|
38
|
Dayan FE, Owens DK, Corniani N, Silva FML, Watson SB, Howell J, Shaner DL. Biochemical Markers and Enzyme Assays for Herbicide Mode of Action and Resistance Studies. WEED SCIENCE 2015; 63:23-63. [PMID: 0 DOI: 10.1614/ws-d-13-00063.1] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/25/2023]
Abstract
Herbicides inhibit biochemical and physiological processes or both with lethal consequences. The target sites of these small molecules are usually enzymes involved in primary metabolic pathways or proteins carrying out essential physiological functions. Herbicides tend to be highly specific for their respective target sites and have served as tools to study these physiological and biochemical processes in plants (Dayan et al. 2010b).
Collapse
|
39
|
Dormontt EE, Gardner MG, Breed MF, Rodger JG, Prentis PJ, Lowe AJ. Genetic bottlenecks in time and space: reconstructing invasions from contemporary and historical collections. PLoS One 2014; 9:e106874. [PMID: 25192006 PMCID: PMC4156389 DOI: 10.1371/journal.pone.0106874] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2014] [Accepted: 08/09/2014] [Indexed: 02/02/2023] Open
Abstract
Herbarium accession data offer a useful historical botanical perspective and have been used to track the spread of plant invasions through time and space. Nevertheless, few studies have utilised this resource for genetic analysis to reconstruct a more complete picture of historical invasion dynamics, including the occurrence of separate introduction events. In this study, we combined nuclear and chloroplast microsatellite analyses of contemporary and historical collections of Senecio madagascariensis, a globally invasive weed first introduced to Australia c. 1918 from its native South Africa. Analysis of nuclear microsatellites, together with temporal spread data and simulations of herbarium voucher sampling, revealed distinct introductions to south-eastern Australia and mid-eastern Australia. Genetic diversity of the south-eastern invasive population was lower than in the native range, but higher than in the mid-eastern invasion. In the invasive range, despite its low resolution, our chloroplast microsatellite data revealed the occurrence of new haplotypes over time, probably as the result of subsequent introduction(s) to Australia from the native range during the latter half of the 20th century. Our work demonstrates how molecular studies of contemporary and historical field collections can be combined to reconstruct a more complete picture of the invasion history of introduced taxa. Further, our study indicates that a survey of contemporary samples only (as undertaken for the majority of invasive species studies) would be insufficient to identify potential source populations and occurrence of multiple introductions.
Collapse
Affiliation(s)
- Eleanor E. Dormontt
- Australian Centre for Evolutionary Biology and Biodiversity, University of Adelaide, Adelaide, South Australia, Australia
| | - Michael G. Gardner
- School of Biological Sciences, Flinders University, Adelaide, South Australia, Australia
- Evolutionary Biology Unit, South Australian Museum, Adelaide, South Australia, Australia
| | - Martin F. Breed
- Australian Centre for Evolutionary Biology and Biodiversity, University of Adelaide, Adelaide, South Australia, Australia
| | - James G. Rodger
- Centre for Invasion Biology, University of KwaZulu-Natal, Pietermaritzburg, South Africa
| | - Peter J. Prentis
- School of Earth, Environmental and Biological Sciences, Queensland University of Technology, Brisbane, Queensland, Australia
| | - Andrew J. Lowe
- Australian Centre for Evolutionary Biology and Biodiversity, University of Adelaide, Adelaide, South Australia, Australia
- * E-mail:
| |
Collapse
|
40
|
Brueggeman AJ, Kuehler D, Weeks DP. Evaluation of three herbicide resistance genes for use in genetic transformations and for potential crop protection in algae production. PLANT BIOTECHNOLOGY JOURNAL 2014; 12:894-902. [PMID: 24796724 DOI: 10.1111/pbi.12192] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/26/2013] [Revised: 03/03/2014] [Accepted: 03/10/2014] [Indexed: 05/09/2023]
Abstract
Genes conferring resistance to the herbicides glyphosate, oxyfluorfen and norflurazon were developed and tested for use as dominant selectable markers in genetic transformation of Chlamydomonas reinhardtii and as potential tools for the protection of commercial-scale algal production facilities against contamination by organisms sensitive to these broad-spectrum herbicides. A synthetic glyphosate acetyltransferase (GAT) gene, when fitted with a strong Chlamydomonas promoter, conferred a 2.7×-fold increase in tolerance to the EPSPS inhibitor, glyphosate, in transgenic cells compared with progenitor WT cells. A mutant Chlamydomonas protoporphyrinogen oxidase (protox, PPO) gene previously shown to produce an enzyme insensitive to PPO-inhibiting herbicides, when genetically engineered, generated transgenic cells able to tolerate up to 136× higher levels of the PPO inhibitor, oxyfluorfen, than nontransformed cells. Genetic modification of the Chlamydomonas phytoene desaturase (PDS) gene-based gene sequences found in various norflurazon-resistant organisms allowed production of transgenic cells tolerant to 40× higher levels of norflurazon than nontransgenic cells. The high efficiency of all three herbicide resistance genes in producing transgenic cells demonstrated their suitability as dominant selectable markers for genetic transformation of Chlamydomonas and, potentially, other eukaryotic algae. However, the requirement for high concentrations of glyphosate and its associated negative effects on cell growth rates preclude its consideration for use in large-scale production facilities. In contrast, only low doses of norflurazon and oxyfluorfen (~1.5 μm and ~0.1 μm, respectively) are required for inhibition of cell growth, suggesting that these two herbicides may prove effective in large-scale algal production facilities in suppressing growth of organisms sensitive to these herbicides.
Collapse
|
41
|
Goggin DE, Powles SB. Fluridone: a combination germination stimulant and herbicide for problem fields? PEST MANAGEMENT SCIENCE 2014; 70:1418-1424. [PMID: 24408127 DOI: 10.1002/ps.3721] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/18/2013] [Revised: 12/10/2013] [Accepted: 01/09/2014] [Indexed: 06/03/2023]
Abstract
BACKGROUND Problem weeds in agriculture, such as Lolium rigidum Gaud., owe some of their success to their large and dormant seed banks, which permit germination throughout a crop-growing season. Dormant weed seed banks could be greatly depleted by application of a chemical that stimulates early-season germination and then kills the young seedlings. Fluridone, a phytoene desaturase-inhibiting herbicide that can also break seed dormancy, was assessed for its efficacy in this regard. RESULTS The germination of fluridone-treated Lolium rigidum seeds was stimulated on soils with low organic matter, and almost 100% seedling mortality was observed, while the treatment was only moderately effective on a high-organic-matter potting mix. Seedlings from wheat, canola, common bean and chickpea seeds sown on fluridone-treated sandy loam were bleached and did not survive, but lupins and field peas grew normally. CONCLUSION This proof-of-concept study with fluridone suggests that it may be possible to design safe and effective molecules that act as germination stimulants plus herbicides in a range of crop and soil types: a potentially novel way of utilising herbicides to stimulate seed bank germination and a valuable addition to an integrated weed management system.
Collapse
Affiliation(s)
- Danica E Goggin
- Australian Herbicide Resistance Initiative, School of Plant Biology, University of Western Australia, Crawley, Australia
| | | |
Collapse
|
42
|
Dayan FE, Owens DK, Tranel PJ, Preston C, Duke SO. Evolution of resistance to phytoene desaturase and protoporphyrinogen oxidase inhibitors--state of knowledge. PEST MANAGEMENT SCIENCE 2014; 70:1358-66. [PMID: 24446422 DOI: 10.1002/ps.3728] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/01/2013] [Revised: 01/06/2014] [Accepted: 01/20/2014] [Indexed: 05/25/2023]
Abstract
Two major classes of herbicides include inhibitors of protoporphyrinogen oxidase (PPO) and phytoene desaturase (PDS). Plants can evolve resistance to PPO and PDS inhibitors via several mechanisms that include physical changes, resulting in reduced uptake, physiological changes, resulting in compartmentalization or altered translocation, and biochemical changes, resulting in enhanced metabolic degradation or alterations of protein structures, leading to loss of sensitivity to the herbicides. This review discusses the involvement of some of these mechanisms in the various cases of resistance to PDS- and PPO-inhibiting herbicides, and highlights unique aspects of target-site resistance to these herbicides.
Collapse
Affiliation(s)
- Franck E Dayan
- Natural Products Utilization Research Unit, United States Department of Agriculture - Agricultural Research Service, University, MS, USA
| | | | | | | | | |
Collapse
|
43
|
Suarez JV, Banks S, Thomas PG, Day A. A new F131V mutation in Chlamydomonas phytoene desaturase locates a cluster of norflurazon resistance mutations near the FAD-binding site in 3D protein models. PLoS One 2014; 9:e99894. [PMID: 24936791 PMCID: PMC4061028 DOI: 10.1371/journal.pone.0099894] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2014] [Accepted: 05/20/2014] [Indexed: 11/18/2022] Open
Abstract
The green alga Chlamydomonas reinhardtii provides a tractable genetic model to study herbicide mode of action using forward genetics. The herbicide norflurazon inhibits phytoene desaturase, which is required for carotenoid synthesis. Locating amino acid substitutions in mutant phytoene desaturases conferring norflurazon resistance provides a genetic approach to map the herbicide binding site. We isolated a UV-induced mutant able to grow in very high concentrations of norflurazon (150 µM). The phytoene desaturase gene in the mutant strain contained the first resistance mutation to be localised to the dinucleotide-binding Rossmann-likedomain. A highly conserved phenylalanine amino acid at position 131 of the 564 amino acid precursor protein was changed to a valine in the mutant protein. F131, and two other amino acids whose substitution confers norflurazon resistance in homologous phytoene desaturase proteins, map to distant regions in the primary sequence of the C. reinhardtii protein (V472, L505) but in tertiary models these residues cluster together to a region close to the predicted FAD binding site. The mutant gene allowed direct 5 µM norflurazon based selection of transformants, which were tolerant to other bleaching herbicides including fluridone, flurtamone, and diflufenican but were more sensitive to beflubutamid than wild type cells. Norflurazon resistance and beflubutamid sensitivity allow either positive or negative selection against transformants expressing the mutant phytoene desaturase gene.
Collapse
Affiliation(s)
- Julio V. Suarez
- Faculty of Life Sciences, The University of Manchester, Manchester, United Kingdom
| | - Stephen Banks
- Faculty of Life Sciences, The University of Manchester, Manchester, United Kingdom
| | | | - Anil Day
- Faculty of Life Sciences, The University of Manchester, Manchester, United Kingdom
| |
Collapse
|
44
|
Les DH, Peredo EL, Benoit LK, Tippery NP, King UM, Sheldon SP. Phytogeography of Najas gracillima (Hydrocharitaceae) in North America and its cryptic introduction to California. AMERICAN JOURNAL OF BOTANY 2013; 100:1905-1915. [PMID: 24018853 DOI: 10.3732/ajb.1300005] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/02/2023]
Abstract
PREMISE OF THE STUDY The discontinuous North American distribution of Najas gracillima has not been explained satisfactorily. Influences of extirpation, nonindigenous introduction, and postglacial migration on its distribution were evaluated using field, fossil, morphological, and molecular data. Najas is a major waterfowl food, and appropriate conservation measures rely on accurate characterization of populations as indigenous or imperiled. • METHODS Seed lengths of N. gracillima from native Korean populations, a nonindigenous Italian population, and North American populations were compared using digital image analysis. DNA sequence analyses from these regions provided nine nrITS genotypes and eight cpDNA haplotypes. • KEY RESULTS Najas gracillima seeds from Eurasia and California are shorter than those from eastern North America. Nuclear and chloroplast DNA sequences of N. gracillima from Korea and Italy were identical to California material but differed from native eastern North American plants. Eastern North American specimens of N. gracillima at localities above the last glacial maximum boundary were identical or similar genetically to material from the northeastern United States and Atlantic Coastal Plain and Piedmont but divergent from plants of the Interior Highlands-Mississippi Embayment region. • CONCLUSIONS In California, N. gracillima is nonindigenous and introduced from Asia. In eastern North America, populations that colonized deglaciated areas were derived primarily from refugia in the Atlantic Coastal Plain and Piedmont. Genetic data indicate initial postglacial migration to northeastern North America, with subsequent westward dispersal into the Upper Great Lakes. These results differentiate potentially invasive California populations from seriously imperiled indigenous eastern North American populations.
Collapse
Affiliation(s)
- Donald H Les
- Department of Ecology and Evolutionary Biology, University of Connecticut, Storrs, Connecticut 06269-3043, USA
| | | | | | | | | | | |
Collapse
|
45
|
Lasso E, Dalling JW, Bermingham E. Tropical Understory Piper Shrubs Maintain High Levels of Genotypic Diversity Despite Frequent Asexual Recruitment. Biotropica 2012. [DOI: 10.1111/j.1744-7429.2011.00763.x] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
|
46
|
Wymore AS, Keeley ATH, Yturralde KM, Schroer ML, Propper CR, Whitham TG. Genes to ecosystems: exploring the frontiers of ecology with one of the smallest biological units. THE NEW PHYTOLOGIST 2011; 191:19-36. [PMID: 21631507 DOI: 10.1111/j.1469-8137.2011.03730.x] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/30/2023]
Abstract
Genes and their expression levels in individual species can structure whole communities and affect ecosystem processes. Although much has been written about community and ecosystem phenotypes with a few model systems, such as poplar and goldenrod, here we explore the potential application of a community genetics approach with systems involving invasive species, climate change and pollution. We argue that community genetics can reveal patterns and processes that otherwise might remain undetected. To further facilitate the community genetics or genes-to-ecosystem concept, we propose four community genetics postulates that allow for the conclusion of a causal relationship between the gene and its effect on the ecosystem. Although most current studies do not satisfy these criteria completely, several come close and, in so doing, begin to provide a genetic-based understanding of communities and ecosystems, as well as a sound basis for conservation and management practices.
Collapse
Affiliation(s)
- Adam S Wymore
- Department of Biological Sciences, Northern Arizona University, Flagstaff, AZ 86011, USA
| | - Annika T H Keeley
- School of Forestry, Northern Arizona University, Flagstaff, AZ 86011, USA
| | - Kasey M Yturralde
- School of Forestry, Northern Arizona University, Flagstaff, AZ 86011, USA
| | - Melanie L Schroer
- Department of Biological Sciences, Northern Arizona University, Flagstaff, AZ 86011, USA
| | - Catherine R Propper
- Department of Biological Sciences, Northern Arizona University, Flagstaff, AZ 86011, USA
| | - Thomas G Whitham
- Department of Biological Sciences, Northern Arizona University, Flagstaff, AZ 86011, USA
- Merriam-Powell Center for Environmental Research, Northern Arizona University, Flagstaff, AZ 86011, USA
| |
Collapse
|
47
|
Evans JM, Wilkie AC. Life cycle assessment of nutrient remediation and bioenergy production potential from the harvest of hydrilla (Hydrilla verticillata). JOURNAL OF ENVIRONMENTAL MANAGEMENT 2010; 91:2626-2631. [PMID: 20696515 DOI: 10.1016/j.jenvman.2010.07.040] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/30/2009] [Revised: 06/23/2010] [Accepted: 07/19/2010] [Indexed: 05/29/2023]
Abstract
Hydrilla (Hydrilla verticillata) is one of the world's most problematic invasive aquatic plants. Although management of hydrilla overgrowth has often been based on use of chemical herbicides, issues such as the emergence of herbicide-resistant hydrilla biotypes and the need for in situ nutrient remediation strategies have together raised interest in the use of harvester machines as an alternative management approach. Using a life cycle assessment (LCA) approach, we calculated a range of net energy and economic benefits associated with hydrilla harvests and the utilization of biomass for biogas and compost production. Base case scenarios that used moderate data assumptions showed net energy benefit ratios (NEBRs) of 1.54 for biogas production and 1.32 for compost production pathways. NEBRs for these respective pathways rose to 2.11 and 2.68 when labor was excluded as a fossil fuel input. Base case biogas and compost production scenarios respectively showed a monetary benefit cost ratio (BCR) of 1.79 and 1.83. Moreover, very high NEBRs (3.94 for biogas; 6.37 for compost) and BCRs (>11 for both biogas and compost) were found for optimistic scenarios in which waterways were assumed to have high hydrilla biomass density, high nutrient content in biomass, and high priority for nutrient remediation. Energy and economic returns were largely decoupled, with biogas and fertilizer providing the bulk of output energy, while nutrient remediation and herbicide avoidance dominated the economic output calculations. Based on these results, we conclude that hydrilla harvest is likely a suitable and cost-effective management program for many nutrient-impaired waters. Additional research is needed to determine how hydrilla harvesting programs may be most effectively implemented in conjunction with fish and wildlife enhancement objectives.
Collapse
Affiliation(s)
- Jason M Evans
- Soil and Water Science Department, Institute of Food and Agricultural Sciences, University of Florida, Energy Research and Education Park, PO Box 110960, Gainesville, FL 32611-0960, USA.
| | | |
Collapse
|
48
|
Reusch TBH, Boström C. Widespread genetic mosaicism in the marine angiosperm Zostera marina is correlated with clonal reproduction. Evol Ecol 2010. [DOI: 10.1007/s10682-010-9436-8] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
|
49
|
Lambertini C, Riis T, Olesen B, Clayton JS, Sorrell BK, Brix H. Genetic diversity in three invasive clonal aquatic species in New Zealand. BMC Genet 2010; 11:52. [PMID: 20565861 PMCID: PMC2902404 DOI: 10.1186/1471-2156-11-52] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2010] [Accepted: 06/18/2010] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Elodea canadensis, Egeria densa and Lagarosiphon major are dioecious clonal species which are invasive in New Zealand and other regions. Unlike many other invasive species, the genetic variation in New Zealand is very limited. Clonal reproduction is often considered an evolutionary dead end, even though a certain amount of genetic divergence may arise due to somatic mutations. The successful growth and establishment of invasive clonal species may be explained not by adaptability but by pre-existing ecological traits that prove advantageous in the new environment. We studied the genetic diversity and population structure in the North Island of New Zealand using AFLPs and related the findings to the number of introductions and the evolution that has occurred in the introduced area. RESULTS Low levels of genetic diversity were found in all three species and appeared to be due to highly homogeneous founding gene pools. Elodea canadensis was introduced in 1868, and its populations showed more genetic structure than those of the more recently introduced of E. densa (1946) and L. major (1950). Elodea canadensis and L. major, however, had similar phylogeographic patterns, in spite of the difference in time since introduction. CONCLUSIONS The presence of a certain level of geographically correlated genetic structure in the absence of sexual reproduction, and in spite of random human dispersal of vegetative propagules, can be reasonably attributed to post-dispersal somatic mutations. Direct evidence of such evolutionary events is, however, still insufficient.
Collapse
Affiliation(s)
- Carla Lambertini
- Department of Biological Sciences, Plant Biology, Aarhus University, DK-8000 Århus C, Denmark
| | - Tenna Riis
- Department of Biological Sciences, Plant Biology, Aarhus University, DK-8000 Århus C, Denmark
| | - Birgit Olesen
- Department of Biological Sciences, Plant Biology, Aarhus University, DK-8000 Århus C, Denmark
| | - John S Clayton
- National Institute of Water and Atmospheric Research, P.O. Box 11115, Hamilton, New Zealand
| | - Brian K Sorrell
- Department of Biological Sciences, Plant Biology, Aarhus University, DK-8000 Århus C, Denmark
| | - Hans Brix
- Department of Biological Sciences, Plant Biology, Aarhus University, DK-8000 Århus C, Denmark
| |
Collapse
|
50
|
Liu J, Zhong Y, Sun Z, Huang J, Jiang Y, Sandmann G, Chen F. One amino acid substitution in phytoene desaturase makes Chlorella zofingiensis resistant to norflurazon and enhances the biosynthesis of astaxanthin. PLANTA 2010; 232:61-7. [PMID: 20221629 DOI: 10.1007/s00425-010-1132-y] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/05/2010] [Accepted: 02/10/2010] [Indexed: 05/03/2023]
Abstract
A stable Chlorella zofingiensis mutant (E17) produced by chemical mutagen was characterized with respect to growth, astaxanthin biosynthesis, and phytoene desaturation. The mutant E17 could grow well and produce normal levels of colored carotenoids in the presence of 0.25 microM norflurazon, in which the growth of wild type (WT) cells was greatly limited due to inhibited carotenoid formation. Induced by high-light irradiation or glucose, E17 produced 44 or 36% more astaxanthin than WT when cultured in media without norflurazon. A point mutation (C-T) was revealed to occur in the PDS gene of E17, leading to an amino acid change (L516F) in its coding region. The mutated PDS exhibited 31-fold resistance to norflurazon when compared to WT as determined by an in vitro assay. Surprisingly, the mutated PDS exhibited higher efficiency in converting phytoene to zeta-carotene. No difference in PDS transcripts was found between E17 and WT cells cultured either in normal or induced conditions. In contrast, higher transcript levels of beta-carotene ketolase and hydroxylase were found in the E17 cells. Taken together, we conclude that a point mutation in Chlorella PDS gene makes E17 resistant to norflurazon and synthesize higher amounts of carotenoids including astaxanthin.
Collapse
Affiliation(s)
- Jin Liu
- School of Biological Science, The University of Hong Kong, Hong Kong, China
| | | | | | | | | | | | | |
Collapse
|