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Georgiou A, Sieber S, Hsiao CC, Grayfer T, Gorenflos López JL, Gademann K, Eberl L, Bailly A. Leaf nodule endosymbiotic Burkholderia confer targeted allelopathy to their Psychotria hosts. Sci Rep 2021; 11:22465. [PMID: 34789815 PMCID: PMC8599487 DOI: 10.1038/s41598-021-01867-2] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2021] [Accepted: 11/03/2021] [Indexed: 11/11/2022] Open
Abstract
After a century of investigations, the function of the obligate betaproteobacterial endosymbionts accommodated in leaf nodules of tropical Rubiaceae remained enigmatic. We report that the α-D-glucose analogue (+)-streptol, systemically supplied by mature Ca. Burkholderia kirkii nodules to their Psychotria hosts, exhibits potent and selective root growth inhibiting activity. We provide compelling evidence that (+)-streptol specifically affects meristematic root cells transitioning to anisotropic elongation by disrupting cell wall organization in a mechanism of action that is distinct from canonical cellulose biosynthesis inhibitors. We observed no inhibitory or cytotoxic effects on organisms other than seed plants, further suggesting (+)-streptol as a bona fide allelochemical. We propose that the suppression of growth of plant competitors is a major driver of the formation and maintenance of the Psychotria-Burkholderia association. In addition to potential agricultural applications as a herbicidal agent, (+)-streptol might also prove useful to dissect plant cell and organ growth processes.
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Affiliation(s)
- Antri Georgiou
- Institute of Plant and Microbial Biology, University of Zürich, Zollikerstrasse 107, 8008, Zürich, Switzerland
| | - Simon Sieber
- Department of Chemistry, University of Zürich, Winterthurerstrasse 190, 8057, Zurich, Switzerland
| | - Chien-Chi Hsiao
- Department of Chemistry, University of Zürich, Winterthurerstrasse 190, 8057, Zurich, Switzerland
| | - Tatyana Grayfer
- Department of Chemistry, University of Zürich, Winterthurerstrasse 190, 8057, Zurich, Switzerland
| | - Jacob L Gorenflos López
- Department of Chemistry, University of Zürich, Winterthurerstrasse 190, 8057, Zurich, Switzerland
| | - Karl Gademann
- Department of Chemistry, University of Zürich, Winterthurerstrasse 190, 8057, Zurich, Switzerland
| | - Leo Eberl
- Institute of Plant and Microbial Biology, University of Zürich, Zollikerstrasse 107, 8008, Zürich, Switzerland.
| | - Aurélien Bailly
- Institute of Plant and Microbial Biology, University of Zürich, Zollikerstrasse 107, 8008, Zürich, Switzerland.
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Qu T, Du X, Peng Y, Guo W, Zhao C, Losapio G. Invasive species allelopathy decreases plant growth and soil microbial activity. PLoS One 2021; 16:e0246685. [PMID: 33561161 PMCID: PMC7872269 DOI: 10.1371/journal.pone.0246685] [Citation(s) in RCA: 16] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2020] [Accepted: 01/23/2021] [Indexed: 11/19/2022] Open
Abstract
According to the 'novel weapons hypothesis', invasive success depends on harmful plant biochemicals, including allelopathic antimicrobial roots exudate that directly inhibit plant growth and soil microbial activity. However, the combination of direct and soil-mediated impacts of invasive plants via allelopathy remains poorly understood. Here, we addressed the allelopathic effects of an invasive plant species (Rhus typhina) on a cultivated plant (Tagetes erecta), soil properties and microbial communities. We grew T. erecta on soil samples at increasing concentrations of R. typhina root extracts and measured both plant growth and soil physiological profile with community-level physiological profiles (CLPP) using Biolog Eco-plates incubation. We found that R. typhina root extracts inhibit both plant growth and soil microbial activity. Plant height, Root length, soil organic carbon (SOC), total nitrogen (TN) and AWCD were significantly decreased with increasing root extract concentration, and plant above-ground biomass (AGB), below-ground biomass (BGB) and total biomass (TB) were significantly decreased at 10 mg·mL-1 of root extracts. In particular, root extracts significantly reduced the carbon source utilization of carbohydrates, carboxylic acids and polymers, but enhanced phenolic acid. Redundancy analysis shows that soil pH, TN, SOC and EC were the major driving factors of soil microbial activity. Our results indicate that strong allelopathic impact of root extracts on plant growth and soil microbial activity by mimicking roots exudate, providing novel insights into the role of plant-soil microbe interactions in mediating invasion success.
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Affiliation(s)
- Tongbao Qu
- College of Horticulture, Jilin Agricultural University, Changchun, PR China
| | - Xue Du
- College of Horticulture, Jilin Agricultural University, Changchun, PR China
| | - Yulan Peng
- College of Horticulture, Jilin Agricultural University, Changchun, PR China
| | - Weiqiang Guo
- College of Horticulture, Jilin Agricultural University, Changchun, PR China
| | - Chunli Zhao
- College of Horticulture, Jilin Agricultural University, Changchun, PR China
| | - Gianalberto Losapio
- Department of Biology, Stanford University, Stanford, CA, United States of America
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Konarzewska Z, Śliwińska-Wilczewska S, Felpeto AB, Vasconcelos V, Latała A. Assessment of the Allelochemical Activity and Biochemical Profile of Different Phenotypes of Picocyanobacteria from the Genus Synechococcus. Mar Drugs 2020; 18:md18040179. [PMID: 32230878 PMCID: PMC7230558 DOI: 10.3390/md18040179] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2020] [Revised: 03/20/2020] [Accepted: 03/25/2020] [Indexed: 11/17/2022] Open
Abstract
Organisms belonging to Synechococcus sp. genera are observed in all freshwater, brackish, and marine waters of the world. They play a relevant role in these ecosystems, since they are one of the main primary producers, especially in open ocean. Eventually, they form mass blooms in coastal areas, which are potentially dangerous for the functioning of marine ecosystems. Allelopathy could be an important factor promoting the proliferation of these organisms. According to the authors’ best knowledge, there is no information on the allelopathic activity and allelopathic compounds exhibited by different Synechococcus sp. phenotypes. Therefore, the research conducted here aimed to study the bioactivity of compounds produced by three phenotypes of Synechococcus sp. by studying their influence on the growth, chlorophyll fluorescence, and photosynthetic pigments of eighteen cyanobacteria and microalgae species. We demonstrated that three different Synechococcus sp. phenotypes, including a phycocyanin (PC)-rich strain (Type 1; green strain) and phycoerythrin (PE)-rich strains containing phycoerythrobilin (PEB) and phycocyanobilin (PCB) (Type 2; red strain and Type 3a; brown strain), had a significant allelopathic effect on the selected species of cyanobacteria, diatoms, and green algae. For all green algae, a decrease in cell abundance under the influence of phenotypes of donor cyanobacteria was shown, whereas, among some target cyanobacteria and diatom species, the cell-free filtrate was observed to have a stimulatory effect. Our estimates of the stress on photosystem II (Fv/Fm) showed a similar pattern, although for some diatoms, there was an effect of stress on photosynthesis, while a stimulatory effect on growth was also displayed. The pigment content was affected by allelopathy in most cases, particularly for chlorophyll a, whilst it was a bit less significant for carotenoids. Our results showed that Synechococcus sp. Type 3a had the strongest effect on target species, while Synechococcus sp. Type 1 had the weakest allelopathic effect. Furthermore, GC-MS analysis produced different biochemical profiles for the Synechococcus strains. For every phenotype, the most abundant compound was different, with oxime-, methoxy-phenyl- being the most abundant substance for Synechococcus Type 1, eicosane for Synechococcus Type 2, and silanediol for Synechococcus Type 3a.
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Affiliation(s)
- Zofia Konarzewska
- Division of Marine Ecosystems Functioning, Institute of Oceanography, University of Gdańsk, Av. Piłsudskiego 46, 81-378 Gdynia, Poland; (S.Ś.-W.); (A.L.)
- Correspondence:
| | - Sylwia Śliwińska-Wilczewska
- Division of Marine Ecosystems Functioning, Institute of Oceanography, University of Gdańsk, Av. Piłsudskiego 46, 81-378 Gdynia, Poland; (S.Ś.-W.); (A.L.)
| | - Aldo Barreiro Felpeto
- Interdisciplinary Center of Marine and Environmental Research–CIMAR/CIIMAR, University of Porto, Av. General Norton de Matos s/n, 4450-208 Matosinhos, Portugal; (A.B.F.); (V.V.)
| | - Vitor Vasconcelos
- Interdisciplinary Center of Marine and Environmental Research–CIMAR/CIIMAR, University of Porto, Av. General Norton de Matos s/n, 4450-208 Matosinhos, Portugal; (A.B.F.); (V.V.)
- Department of Biology, Faculty of Sciences, Porto University, Rua do Campo Alegre, 4069-007 Porto, Portugal
| | - Adam Latała
- Division of Marine Ecosystems Functioning, Institute of Oceanography, University of Gdańsk, Av. Piłsudskiego 46, 81-378 Gdynia, Poland; (S.Ś.-W.); (A.L.)
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Xie J, Tang W, Zhao L, Liu S, Liu K, Liu W. Enantioselectivity and allelopathy both have effects on the inhibition of napropamide on Echinochloa crus-galli. Sci Total Environ 2019; 682:151-159. [PMID: 31112816 DOI: 10.1016/j.scitotenv.2019.05.058] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/18/2019] [Revised: 05/05/2019] [Accepted: 05/05/2019] [Indexed: 06/09/2023]
Abstract
Napropamide is a chiral acetamide herbicide commonly applied to control Echinochloa crus-galli in maize. The inhibition effect may be enantioselective for Echinochloa crus-galli and maize. It may also be affected by the potential allelopathy at field condition. To investigate this, we have examined the inhibition effect of napropamide on Echinochloa crus-galli mono-cultured or co-cultured with maize at field conditions. Our results on morphology, physiology, chlorophyll content and chlorophyll fluorescence suggest that R-napropamide has stronger inhibitory effect than Rac-napropamide and S-napropamide on Echinochloa crus-galli, while none of them affects maize. We found that both glutathione-S-transferase (GST) genes and oxidative enzymes (superoxide dismutase, malondialdehyde) played roles in the inhibition. Accumulations of napropamide in Echinochloa crus-galli were more prominent in roots than in shoots, and no enantioselectivity was found in medium dissipation. We have observed relative allelopathy when applying napropamide to Echinochloa crus-galli co-cultured with maize. The results warrant further field studies on the enantioselectivity and allelopathy of herbicides.
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Affiliation(s)
- Jingqian Xie
- College of Marine Ecology and Environment, Shanghai Ocean University, Shanghai 201306, China; MOE Key Laboratory of Environmental Remediation and Ecosystem Health, College of Environmental and Resource Sciences, Zhejiang University, Hangzhou 310058, China
| | - Wei Tang
- State Key Laboratory of Rice Biology, China National Rice Research Institute, Hangzhou 311400, China
| | - Lu Zhao
- MOE Key Laboratory of Environmental Remediation and Ecosystem Health, College of Environmental and Resource Sciences, Zhejiang University, Hangzhou 310058, China
| | - Shuren Liu
- MOE Key Laboratory of Environmental Remediation and Ecosystem Health, College of Environmental and Resource Sciences, Zhejiang University, Hangzhou 310058, China
| | - Kai Liu
- Division of Engineering and Applied Science, W. M. Keck Laboratories, California Institute of Technology, 1200 East California Blvd., Pasadena, CA 91125, United States
| | - Weiping Liu
- MOE Key Laboratory of Environmental Remediation and Ecosystem Health, College of Environmental and Resource Sciences, Zhejiang University, Hangzhou 310058, China.
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Xiao T, Yu H, Song YB, Jiang YP, Zeng B, Dong M. Nutrient enhancement of allelopathic effects of exotic invasive on native plant species. PLoS One 2019; 14:e0206165. [PMID: 30673697 PMCID: PMC6343864 DOI: 10.1371/journal.pone.0206165] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/27/2018] [Accepted: 10/08/2018] [Indexed: 11/18/2022] Open
Abstract
Many ecosystems may suffer from both nutrient enrichment and exotic plant invasions simultaneously. Much has been known that nutrient inputs can promote growth and expansion of exotic invasive plants in wetlands, and that allelopathic effects of the exotic invasive plants can inhibit the growth of coexisting native plants, contributing to their invasion success. Thus, we hypothesized that allelopathic effects of exotics on natives in invaded ecosystems can be enhanced by nutrient enrichment. To test this hypothesis, we conducted two greenhouse hydroponic experiments. One is the monoculture experiment in which a widespread exotic invasive perennial Alternanthera philoxeroides and a native perennial Ludwigia peploides subsp. stipulacea in monoculture were subjected to five levels of nutrient supply. The other is the mixture experiment in which the two species in mixture were subjected to five levels of nutrient supply, each with and without activated carbon addition. Both A. philoxeroides and L. peploides grew better under higher level of nutrient availability in monoculture experiment. In the mixture experiment, A. philoxeroides formed less total and root biomass while L. peploides formed more in response to activated carbon addition and all of the responses had larger degree at higher level of nutrient availability, indicating A. philoxeroides had significant allelopathic effects on L. peploides and the effects was significantly enhanced by nutrient enrichment. Such results support our hypothesis and reveal a novel mechanism for exotic plant invasion in eutrophicated and invaded wetlands, i.e. nutrient enhancement of allelopathic effects of exotics on natives.
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Affiliation(s)
- Tao Xiao
- Key Laboratory of Eco-environments in Three Gorges Reservoir Region (Ministry of Education), Chongqing Key Laboratory of Plant Ecology and Resources in Three Gorges Reservoir Region, School of Life Sciences, Southwest University, Chongqing, China
- Key Laboratory of Hangzhou City for Ecosystem Protection and Restoration, College of Life and Environmental Sciences, Hangzhou Normal University, Hangzhou, China
| | - Hua Yu
- Key Laboratory of Hangzhou City for Ecosystem Protection and Restoration, College of Life and Environmental Sciences, Hangzhou Normal University, Hangzhou, China
| | - Yao-Bin Song
- Key Laboratory of Hangzhou City for Ecosystem Protection and Restoration, College of Life and Environmental Sciences, Hangzhou Normal University, Hangzhou, China
| | - Yue-Ping Jiang
- Hangzhou Xixi National Wetland Park Research Center for Ecological Sciences, Hangzhou, China
| | - Bo Zeng
- Key Laboratory of Eco-environments in Three Gorges Reservoir Region (Ministry of Education), Chongqing Key Laboratory of Plant Ecology and Resources in Three Gorges Reservoir Region, School of Life Sciences, Southwest University, Chongqing, China
- * E-mail: (BJ); (MD)
| | - Ming Dong
- Key Laboratory of Eco-environments in Three Gorges Reservoir Region (Ministry of Education), Chongqing Key Laboratory of Plant Ecology and Resources in Three Gorges Reservoir Region, School of Life Sciences, Southwest University, Chongqing, China
- Key Laboratory of Hangzhou City for Ecosystem Protection and Restoration, College of Life and Environmental Sciences, Hangzhou Normal University, Hangzhou, China
- * E-mail: (BJ); (MD)
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Poulin RX, Poulson-Ellestad KL, Roy JS, Kubanek J. Variable allelopathy among phytoplankton reflected in red tide metabolome. Harmful Algae 2018; 71:50-56. [PMID: 29306396 DOI: 10.1016/j.hal.2017.12.002] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/12/2017] [Revised: 12/04/2017] [Accepted: 12/08/2017] [Indexed: 06/07/2023]
Abstract
Harmful algae are known to utilize allelopathy, the release of compounds that inhibit competitors, as a form of interference competition. Competitor responses to allelopathy are species-specific and allelopathic potency of producing algae is variable. In the current study, the biological variability in allelopathic potency was mapped to the underlying chemical variation in the exuded metabolomes of five genetic strains of the red tide dinoflagellate Karenia brevis using 1H nuclear magnetic resonance (NMR) spectroscopy. The impacts of K. brevis allelopathy on growth of a model competitor, Asterionellopsis glacialis, ranged from strongly inhibitory to negligible to strongly stimulatory. Unique metabolomes of K. brevis were visualized as chemical fingerprints, suggesting three distinct metabolic modalities - allelopathic, non-allelopathic, and stimulatory - with each modality distinguished from the others by different concentrations of several metabolites. Allelopathic K. brevis was characterized by enhanced concentrations of fatty acid-derived lipids and aromatic or other polyunsaturated compounds, relative to less allelopathic K. brevis. These findings point to a previously untapped source of information in the study of allelopathy: the chemical variability of phytoplankton, which has been underutilized in the study of bloom dynamics and plankton chemical ecology.
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Affiliation(s)
- Remington X Poulin
- School of Chemistry and Biochemistry, Georgia Institute of Technology, 901 Atlantic Dr, Atlanta, GA, 30332, USA; Aquatic Chemical Ecology Center, Georgia Institute of Technology, Atlanta, GA 30332, USA.
| | - Kelsey L Poulson-Ellestad
- School of Biological Sciences, Georgia Institute of Technology, 950 Atlantic Dr, Atlanta, GA, 30332, USA; Department of Biological, Chemical, and Physical Sciences, Roosevelt University, 430 S Michigan Avenue, Chicago, IL 60605, USA; Aquatic Chemical Ecology Center, Georgia Institute of Technology, Atlanta, GA 30332, USA.
| | - Jessie S Roy
- School of Biological Sciences, Georgia Institute of Technology, 950 Atlantic Dr, Atlanta, GA, 30332, USA; Aquatic Chemical Ecology Center, Georgia Institute of Technology, Atlanta, GA 30332, USA.
| | - Julia Kubanek
- School of Chemistry and Biochemistry, Georgia Institute of Technology, 901 Atlantic Dr, Atlanta, GA, 30332, USA; School of Biological Sciences, Georgia Institute of Technology, 950 Atlantic Dr, Atlanta, GA, 30332, USA; Parker H. Petit Institute for Bioengineering and Bioscience, Georgia Institute of Technology, 315 Ferst Drive, Atlanta, GA 30332, USA; Aquatic Chemical Ecology Center, Georgia Institute of Technology, Atlanta, GA 30332, USA.
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El Ayeb-Zakhama A, Sakka-Rouis L, Flamini G, Ben Jannet H, Harzallah-Skhiri F. Chemical Composition and Allelopathic Potential of Essential Oils from Citharexylum spinosum L. Grown in Tunisia. Chem Biodivers 2017; 14. [PMID: 27685082 DOI: 10.1002/cbdv.201600225] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2016] [Accepted: 09/26/2016] [Indexed: 12/16/2023]
Abstract
Citharexylum spinosum L. (Verbenaceae) also known as Citharexylum quadrangulare Jacq. or Citharexylum fruticosum L. is an exotic tree introduced many years ago in Tunisia, specially used as a street and park ornamental tree. Essential oils (EOs) were obtained by hydrodistillation of the different parts (roots, stems, leaves, flowers and fruits; drupes) collected from trees grown in the area of Monastir (Tunisia). In total, 84 compounds, representing 90.1 - 98.4% of the whole oil composition, were identified by GC-FID and GC/MS analyses. The root EO was distinguished by its high content in monoterpene hydrocarbons (α-phellandrene; 30.8%) whereas that obtained from stems was dominated by sesquiterpene hydrocarbons (cuparene; 16.4%). The leaf oil was rich in an apocarotenoid derivative (hexahydrofarnesylacetone; 26%) and an aliphatic hydrocarbon (nonadecane; 14.5%). Flowers oil was rich in esters (2-phenylethyl benzoate; 33.5%). Finally, drupes oil was rich in oxygenated sesquiterpenes (β-eudesmol; 33.1%). Flowers oil showed a significant phytotoxic effect against lettuce seeds germination, it induces a total inhibition when tested at 1 mg/ml. Root and shoot elongation seemed to be more affected than germination. The inhibition of the shoot length varied from 3.6% to 100% and that of the root from 16.1% to 100%. The highest inhibition of 100% was detected for flower oil tested at 1 mg/ml. Our in vitro studies suggest a possible and new alternative use of C. spinosum EOs in herbicidal formulations, further experiments involving field conditions are necessary to confirm its herbicidal potential.
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Affiliation(s)
- Asma El Ayeb-Zakhama
- Laboratory of Genetics Biodiversity and Valorisation of Bio-resources (LR11ES41), High Institute of Biotechnology of Monastir, University of Monastir, Monastir, Tunisia
| | - Lamia Sakka-Rouis
- Laboratory of Genetics Biodiversity and Valorisation of Bio-resources (LR11ES41), High Institute of Biotechnology of Monastir, University of Monastir, Monastir, Tunisia
| | - Guido Flamini
- Dipartimento di Farmacia, Università di Pisa, Via Bonanno 33, IT-56126, Pisa, Italy
| | - Hichem Ben Jannet
- Laboratory of Heterocyclic Chemistry, Natural Products and Reactivity, Team: Medicinal Chemistry and Natural Products, Faculty of Sciences of Monastir, University of Monastir, Monastir, Tunisia
| | - Fethia Harzallah-Skhiri
- Laboratory of Genetics Biodiversity and Valorisation of Bio-resources (LR11ES41), High Institute of Biotechnology of Monastir, University of Monastir, Monastir, Tunisia
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Abstract
As climate change continues to alter seawater temperature and chemistry on a global scale, coral reefs show multiple signs of degradation. One natural process that could facilitate the recovery of reef ecosystems is coral recruitment, which can be influenced by the benthic organisms in a local habitat. We experimentally tested both a global stressor (increased seawater temperature) and a local stressor (exposure to microcolin A, a natural product from a common marine benthic cyanobacterium) to determine how these stressors impacted coral larval sublethal stress, survival and settlement. Larvae of Porites astreoides had the same survival and settlement as the controls after exposure to increased temperature alone, but elevated temperature did cause oxidative stress. When exposed to natural concentrations of microcolin A, larval survival and settlement were significantly reduced. When larvae were exposed to these two stressors sequentially there was no interactive effect; but when exposed to both stressors simultaneously, there was a synergistic reduction in larval survival and an increase in oxidative stress more than in either stressor treatment alone. Increased seawater temperatures made larvae more susceptible to a concurrent local stressor disrupting a key process of coral reef recovery and resilience. These results highlight the importance of understanding how interactive stressors of varying spatial scales can impact coral demographics.
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Affiliation(s)
- Raphael Ritson-Williams
- Smithsonian Marine Station at Fort Pierce, Fort Pierce, FL, United States of America
- Department of Biology, University of Hawaii at Manoa, Honolulu, HI, United States of America
| | - Cliff Ross
- Department of Biology, University of North Florida, 1 UNF Drive, Jacksonville, FL, United States of America
| | - Valerie J. Paul
- Smithsonian Marine Station at Fort Pierce, Fort Pierce, FL, United States of America
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Zuo S, Zhou S, Ye L, Ding Y, Jiang X. Antialgal effects of five individual allelochemicals and their mixtures in low level pollution conditions. Environ Sci Pollut Res Int 2016; 23:15703-15711. [PMID: 27137194 DOI: 10.1007/s11356-016-6770-6] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/09/2015] [Accepted: 04/26/2016] [Indexed: 06/05/2023]
Abstract
An effective, environmentally friendly, and eco-sustainable approach for removing harmful microalgae is exploiting the allelopathic potential of aquatic macrophytes. In this study, we simulated field pollution conditions in the laboratory to investigate algal inhibition by allelochemicals, thereby providing insights into field practices. We tested five allelochemicals, i.e., coumarin, ρ-hydroxybenzoic acid, protocatechuic acid, stearic acid, and ρ-aminobenzenesulfonic acid, and a typical green alga, Chlorella pyrenoidosa, under two conditions. In the unpolluted treatment, individual allelochemicals had strong algal inhibition effects, where coumarin and ρ-hydroxybenzoic acid had greater potential for algal inhibition than protocatechuic acid, stearic acid, and ρ-aminobenzenesulfonic acid based on the 50 % inhibitory concentration. However, when two or three allelochemicals were mixed in specific proportions, the algal inhibition rate exceeded 80 %, thereby indicating allelopathic synergistic interactions. Mixtures of four or five allelochemicals had weak effects on algal inhibition, which indicated antagonistic interactions. Furthermore, the presence of low lead pollution significantly reduced the antialgal potential of individual allelochemicals, whereas the allelopathic synergistic interactions with mixtures between two or three allelochemicals were changed into antagonistic effects by low pollution. In particular, the allelopathic antagonistic interactions between four or five allelochemicals were increased by pollution. The allelopathic performance of these five allelochemicals may depend on various factors, such as the chemical species, mixture parameters, and algal strain. Thus, we found that low level pollution reduced the allelopathic inhibition of microalgae by allelochemicals. Therefore, the control of algae by the direct addition of allelochemicals should consider various environmental factors.
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Affiliation(s)
- Shengpeng Zuo
- College of Environmental Science and Engineering, Anhui Normal University, 189 South Jiuhua Road, Wuhu, 241003, People's Republic of China.
| | - Shoubiao Zhou
- College of Environmental Science and Engineering, Anhui Normal University, 189 South Jiuhua Road, Wuhu, 241003, People's Republic of China
| | - Liangtao Ye
- College of Environmental Science and Engineering, Anhui Normal University, 189 South Jiuhua Road, Wuhu, 241003, People's Republic of China
| | - Ying Ding
- College of Environmental Science and Engineering, Anhui Normal University, 189 South Jiuhua Road, Wuhu, 241003, People's Republic of China
| | - Xiaofeng Jiang
- College of Environmental Science and Engineering, Anhui Normal University, 189 South Jiuhua Road, Wuhu, 241003, People's Republic of China
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Yang G, Zhou B, Zhang X, Zhang Z, Wu Y, Zhang Y, Lü S, Zou Q, Gao Y, Teng L. Effects of Tomato Root Exudates on Meloidogyne incognita. PLoS One 2016; 11:e0154675. [PMID: 27128659 PMCID: PMC4851295 DOI: 10.1371/journal.pone.0154675] [Citation(s) in RCA: 50] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/24/2015] [Accepted: 04/18/2016] [Indexed: 11/29/2022] Open
Abstract
Plant root exudates affect root-knot nematodes egg hatch. Chemicals in root exudates can attract nematodes to the roots or result in repellence, motility inhibition or even death. However, until recently little was known about the relationship between tomato root exudates chemicals and root-knot nematodes. In this study, root exudates were extracted from three tomato rootstocks with varying levels of nematode resistance: Baliya (highly resistant, HR), RS2 (moderately resistant, MR) and L-402 (highly susceptible, T). The effects of the root exudates on Meloidogyne incognita (M. incognita) egg hatch, survival and chemotaxis of second-stage juveniles (J2) were explored. The composition of the root exudates was analysed by gas chromatography/mass spectrometry (GC/MS) prior to and following M. incognita inoculation. Four compounds in root exudates were selected for further analysis and their allopathic effect on M. incognita were investigated. Root exudates from each tomato rootstocks (HR, MR and T strains) suppressed M. incognita egg hatch and increased J2 mortality, with the highest rate being observed in the exudates from the HR plants. Exudate from HR variety also repelled M. incognita J2 while that of the susceptible plant, T, was demonstrated to be attractive. The relative amount of esters and phenol compounds in root exudates from HR and MR tomato rootstocks increased notably after inoculation. Four compounds, 2,6-Di-tert-butyl-p-cresol, L-ascorbyl 2,6-dipalmitate, dibutyl phthalate and dimethyl phthalate increased significantly after inoculation. The egg hatch of M. incognita was suppressed by each of the compound. L-ascorbyl 2,6-dipalmitate showed the most notable effect in a concentration-dependent manner. All four compounds were associated with increased J2 mortality. The greatest effect was observed with dimethyl phthalate at 2 mmol·L-1. Dibutyl phthalate was the only compound observed to repel M. incognita J2 with no effect being detected in the other compounds. Each of the four compounds were correlated with a reduction in disease index in the susceptible cultivar, T, and tomato seedlings irrigated with L-ascorbyl 2,6-dipalmitate at 2 mmol·L-1 showed the best resistance to M. incognita. Taken together, this study provided a valuable contribution to understanding the underlying mechanism of nematode resistance in tomato cultivars.
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Affiliation(s)
- Guodong Yang
- College of Horticulture, Shenyang Agricultural University, Shenyang, P. R. China
- Vegetable Research Institute, Liaoning Academy of Agricultural Sciences, Shenyang, P. R. China
| | - Baoli Zhou
- College of Horticulture, Shenyang Agricultural University, Shenyang, P. R. China
- * E-mail:
| | - Xinyu Zhang
- Vegetable Research Institute, Liaoning Academy of Agricultural Sciences, Shenyang, P. R. China
| | - Zijun Zhang
- Vegetable Research Institute, Liaoning Academy of Agricultural Sciences, Shenyang, P. R. China
| | - Yuanyuan Wu
- Vegetable Research Institute, Liaoning Academy of Agricultural Sciences, Shenyang, P. R. China
| | - Yiming Zhang
- Vegetable Research Institute, Liaoning Academy of Agricultural Sciences, Shenyang, P. R. China
| | - Shuwen Lü
- Vegetable Research Institute, Liaoning Academy of Agricultural Sciences, Shenyang, P. R. China
| | - Qingdao Zou
- Vegetable Research Institute, Liaoning Academy of Agricultural Sciences, Shenyang, P. R. China
| | - Yuan Gao
- Vegetable Research Institute, Liaoning Academy of Agricultural Sciences, Shenyang, P. R. China
| | - Long Teng
- Vegetable Research Institute, Liaoning Academy of Agricultural Sciences, Shenyang, P. R. China
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11
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Zhang KM, Shen Y, Fang YM, Liu Y. Changes in gametophyte physiology of Pteris multifida induced by the leaf leachate treatment of the invasive Bidens pilosa. Environ Sci Pollut Res Int 2016; 23:3578-85. [PMID: 26490937 DOI: 10.1007/s11356-015-5589-x] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/01/2015] [Accepted: 09/20/2015] [Indexed: 05/26/2023]
Abstract
In recent years, the response of fern gametophytes to environment has raised much attention. However, studies on the influence of plant invasion to fern gametophytes are scarce. Allelopathy plays an important role in biological invasion. Hence, it is necessary to study the allelopathic effects of invasive plants on fern gametophytes and elucidate the mechanisms by which invasive plants cause phytotoxicity. As one of the main invasive plants in China, Bidens pilosa exhibits allelopathic effects on spermatophyte growth. Field investigation shows that many ferns are threatened by the invasion of B. pilosa. The distribution of Pteris multifida overlaps with that of B. pilosa in China. To examine the potential involvement of allelopathic mechanisms of B. pilosa leaves, changes in the physiology in P. multifida gametophytes are analyzed. We found that cell membrane and antioxidant enzyme activities as well as photosynthesis pigment contents of the gametophytes were affected by B. pilosa leachates. Gametophytes of P. multifida exposed to B. pilosa had increased damages to cell membranes, expressed in thiobarbituric acid reacting substance (TBARS) concentrations, malondialdehyde (MDA), electrolyte leakage (membrane permeability), and degree of injury. Enzyme activities, assessed by superoxide dismutase (SOD) and catalase (CAT) as well as guaiacol peroxidase (GPX) enhanced with the increase in leachate concentration after 2-day exposure. Meanwhile, lower chlorophyll a (Chl a), chlorophyll b (Chl b), carotenoid (Car), and the total chlorophyll were measured as leachate concentrations increased. At day 10, leaf leachates of B. pilosa exhibited the greatest inhibition. These results suggest that the observed inhibitory or stimulatory effects on the physiology studied can have an adverse effect on P. multifida and that allelopathic interference seems to have involved in this process.
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Affiliation(s)
- Kai-Mei Zhang
- Co-Innovation Center for Sustainable Forestry in Southern China, Nanjing Forestry University, Nanjing, 210037, Jiangsu, China
- College of Biology and the Environment, Nanjing Forestry University, Nanjing, 210037, Jiangsu, China
- Department of Botany, Smithsonian Institution, Washington, DC, 20013, USA
| | - Yu Shen
- Co-Innovation Center for Sustainable Forestry in Southern China, Nanjing Forestry University, Nanjing, 210037, Jiangsu, China
- College of Biology and the Environment, Nanjing Forestry University, Nanjing, 210037, Jiangsu, China
- College of Resources and Environmental Sciences, Nanjing Agricultural University, Nanjing, 210095, Jiangsu, China
| | - Yan-Ming Fang
- Co-Innovation Center for Sustainable Forestry in Southern China, Nanjing Forestry University, Nanjing, 210037, Jiangsu, China.
- College of Biology and the Environment, Nanjing Forestry University, Nanjing, 210037, Jiangsu, China.
| | - Ying Liu
- Co-Innovation Center for Sustainable Forestry in Southern China, Nanjing Forestry University, Nanjing, 210037, Jiangsu, China
- College of Biology and the Environment, Nanjing Forestry University, Nanjing, 210037, Jiangsu, China
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12
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Al Harun MAY, Johnson J, Uddin MN, Robinson RW. Identification and Phytotoxicity Assessment of Phenolic Compounds in Chrysanthemoides monilifera subsp. monilifera (Boneseed). PLoS One 2015; 10:e0139992. [PMID: 26465595 PMCID: PMC4605635 DOI: 10.1371/journal.pone.0139992] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2014] [Accepted: 09/21/2015] [Indexed: 11/18/2022] Open
Abstract
Chrysanthemoides monilifera subsp. monilifera (boneseed), a weed of national significance in Australia, threatens indigenous species and crop production through allelopathy. We aimed to identify phenolic compounds produced by boneseed and to assess their phytotoxicity on native species. Phenolic compounds in water and methanol extracts, and in decomposed litter-mediated soil leachate were identified using HPLC, and phytotoxicity of identified phenolics was assessed (repeatedly) through a standard germination bioassay on native Isotoma axillaris. The impact of boneseed litter on native Xerochrysum bracteatum was evaluated using field soil in a greenhouse. Collectively, we found the highest quantity of phenolic compounds in boneseed litter followed by leaf, root and stem. Quantity varied with extraction media. The rank of phenolics concentration in boneseed was in the order of ferulic acid > phloridzin > catechin > p-coumaric acid and they inhibited germination of I. axillaris with the rank of ferulic acid > catechin > phloridzin > p-coumaric acid. Synergistic effects were more severe compared to individual phenolics. The litter-mediated soil leachate (collected after15 days) exhibited strong phytotoxicity to I. axillaris despite the level of phenolic compounds in the decomposed leachate being decreased significantly compared with their initial level. This suggests the presence of other unidentified allelochemicals that individually or synergistically contributed to the phytotoxicity. Further, the dose response phytotoxic impacts exhibited by the boneseed litter-mediated soil to native X. bracteatum in a more naturalistic greenhouse experiment might ensure the potential allelopathy of other chemical compounds in the boneseed invasion. The reduction of leaf relative water content and chlorophyll level in X. bracteatum suggest possible mechanisms underpinning plant growth inhibition caused by boneseed litter allelopathy. The presence of a substantial quantity of free proline in the target species also suggests that the plant was in a stressed condition due to litter allelopathy. These findings are important for better understanding the invasive potential of boneseed and in devising control strategies.
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Affiliation(s)
- Md Abdullah Yousuf Al Harun
- Institute for Sustainability and Innovation, College of Engineering and Science, Victoria University, Melbourne, Australia
- * E-mail:
| | - Joshua Johnson
- Institute for Sustainability and Innovation, College of Engineering and Science, Victoria University, Melbourne, Australia
| | - Md Nazim Uddin
- Institute for Sustainability and Innovation, College of Engineering and Science, Victoria University, Melbourne, Australia
| | - Randall W. Robinson
- Institute for Sustainability and Innovation, College of Engineering and Science, Victoria University, Melbourne, Australia
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13
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Zhang SH, Chang JJ, Cao JY, Yang CL. Comparative studies on growth and physiological responses of unicellular and colonial Microcystis aeruginosa to Acorus calamus. Bull Environ Contam Toxicol 2015; 94:225-231. [PMID: 25416545 DOI: 10.1007/s00128-014-1424-1] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/04/2014] [Accepted: 11/12/2014] [Indexed: 06/04/2023]
Abstract
In order to explore the growth inhibition and physiological responses of unicellular and colonial Microcystis aeruginosa during coexistence with Acorus calamus, algal densities, chlorophyll a contents, exopolysaccharide (EPS) concentrations, malondialdehyde (MDA) contents, catalase (CAT) activities, and peroxidase (POD) activities of the two algae strains were analyzed. Although the unicellular and colonial strains of M. aeruginosa were both inhibited by A. calamus, unicellular algae were more sensitive than the colonial algae. The measurement results for EPS, MDA, CAT, and POD showed that unicellular M. aeruginosa had higher levels of stress related damage than colonial strains when they were exposed to the same density of A. calamus, and the cellular defense system of colonial M. aeruginosa was stronger than that of unicellular M. aeruginosa. Natural blooms of Microcystis are typically composed of colonial forms of M. aeruginosa, therefore future efforts to control such blooms, possibly through the development of new algicides, should focus on the unique characteristics of colonial M. aeruginosa strains.
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Affiliation(s)
- S-H Zhang
- Research Institute of Engineering and Technology, Yunnan University, Kunming, 650091, China,
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14
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Abstract
The present study evaluated the combined effects of four typical predatory zooplankton and allelopathic aquatic macrophytes on algal control in a microcosm system. It would determine the effects of diverse species and biological restoration on the growth of harmful water-bloom microalgae in great lakes polluted by excess nutrients. It was found that the mixtures of each zooplankton and the floating plant Nymphoides peltatum had stronger inhibitory effects on harmful water-bloom microalgae than the individual species in clean or eutrophic water bodies. In addition, a community of four zooplankton types had a synergistic effect on algal inhibition. Algal suppression by the zooplankton community was enhanced significantly when the macrophyte was co-cultured in the microcosm. Furthermore, Chlorella pyrenoidosa was more susceptible than Microcystis aeruginosa when exposed to grazing by zooplankton and the allelopathic potential of the macrophyte. Algal inhibition was also weaker in eutrophic conditions compared with the control. These findings indicate that diverse species may enhance algal inhibition. Therefore, it is necessary to restore biological diversity and rebuild an ecologically balanced food chain or web to facilitate the control of harmful algal blooms in eutrophic lakes.
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Affiliation(s)
- Shengpeng Zuo
- a College of Environmental Science and Engineering, Anhui Normal University , Wuhu 241003 , People's Republic of China
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15
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Blossom HE, Rasmussen SA, Andersen NG, Larsen TO, Nielsen KF, Hansen PJ. Prymnesium parvum revisited: relationship between allelopathy, ichthyotoxicity, and chemical profiles in 5 strains. Aquat Toxicol 2014; 157:159-66. [PMID: 25456230 DOI: 10.1016/j.aquatox.2014.10.006] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/10/2014] [Revised: 09/25/2014] [Accepted: 10/12/2014] [Indexed: 05/11/2023]
Abstract
Bioassay-guided discovery of ichthyotoxic algal compounds using in vivo fish assays is labor intensive, costly, and highly regulated. Since the mode of action of most known algal-mediated fish-killing toxins is damage to the cell membranes in the gills, various types of cell-based bioassays are often used for bioassay guided purification of new ichthyotoxins. Here we tested the hypothesis that allelopathy is related to ichthyotoxicity and thus that a microalgal bioassay can be used as a proxy for ichthyotoxicity by comparing the toxicity of five strains of Prymnesium parvum toward rainbow trout (Oncorhynchus mykiss, 10 g) and the microalga Teleaulax acuta. No relationship between median effective concentrations (EC50s) on fish and median lethal concentrations (LC50s) on algae was observed in the 5 strains showing that a microalgal bioassay cannot be used as a proxy for ichthyotoxicity. Fish were more sensitive to P. parvum with EC50s ranging from 6×10(3) to 40×10(3) cells ml(-1), compared to the test alga where LC50s ranged from 30×10(3) to nearly non-toxic at 500×10(3) cells ml(-1). In addition, the cellular concentrations of two recently suggested ichthyotoxins produced by P. parvum, the "golden algae toxins", GAT 512 and a novel GAT 510, did not show any relationship to either ichthyotoxicity or allelopathy, and are not the biologically relevant toxins, but are simply lipids found in algal chloroplasts. Finally, we demonstrate that the recently suggested ichthyotoxin, oleamide, could not be detected in any of the five P. parvum strains above the limit of detection, nor was it found in a (13)C-labeled strain. Instead we document that oleamide can easily be extracted from plastic materials, which may have been the source of oleamide reported previously.
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Affiliation(s)
- Hannah E Blossom
- Marine Biological Section, University of Copenhagen, Strandpromenaden 5, 3000 Helsingør, Denmark.
| | - Silas A Rasmussen
- Department of Systems Biology, Technical University of Denmark, Søltofts Plads, Building 221, 2800 Kgs Lyngby, Denmark
| | - Nikolaj G Andersen
- Marine Biological Section, University of Copenhagen, Strandpromenaden 5, 3000 Helsingør, Denmark
| | - Thomas O Larsen
- Department of Systems Biology, Technical University of Denmark, Søltofts Plads, Building 221, 2800 Kgs Lyngby, Denmark
| | - Kristian F Nielsen
- Department of Systems Biology, Technical University of Denmark, Søltofts Plads, Building 221, 2800 Kgs Lyngby, Denmark
| | - Per J Hansen
- Marine Biological Section, University of Copenhagen, Strandpromenaden 5, 3000 Helsingør, Denmark
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16
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Samedani B, Juraimi AS, Rafii MY, Anuar AR, Sheikh Awadz SA, Anwar MP. Allelopathic effects of litter Axonopus compressus against two weedy species and its persistence in soil. ScientificWorldJournal 2013; 2013:695404. [PMID: 24260020 PMCID: PMC3821928 DOI: 10.1155/2013/695404] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2013] [Accepted: 08/23/2013] [Indexed: 11/18/2022] Open
Abstract
This study investigated the allelopathic effect of Axonopus compressus litter on Asystasia gangetica and Pennisetum polystachion. In experiment 1 the bioassays with 0, 10, 30, and 50 g L⁻¹ of aqueous A. compressus litter leachate were conducted. Experiment 2 was carried out by incorporating 0, 10, 20, 30, 40, and 50 g L⁻¹ of A. compressus litter leachate into soil. In experiment 3, the fate of A. compressus litter leachate phenolics in the soil was investigated. A. compressus leachates did not affect the germination percentage of A. gangetica and P. polystachion, but delayed germination of A. gangetica seeds and decreased seed germination time of P. polystachion. A. compressus litter leachates affected weeds hypocotyl length. Hypocotyl length reductions of 18 and 31% were observed at the highest concentration (50 g L⁻¹) compared to the control in A. gangetica and P. polystachion, respectively. When concentration of A. compressus litter leachate-amended soil increased A. gangetica and P. polystachion seedling shoot length, root length, seedling weight and chlorophyll concentration were not affected. The 5-week decomposition study of A. compressus showed that the phenolic compounds in A. compressus litter abruptly decreased about 52% after two weeks and remained steady until the end of the incubation.
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Affiliation(s)
- B. Samedani
- Department of Crop Science, Faculty of Agriculture, Universiti Putra Malaysia, 43400 UPM, Serdang, Selangor, Malaysia
| | - A. S. Juraimi
- Department of Crop Science, Faculty of Agriculture, Universiti Putra Malaysia, 43400 UPM, Serdang, Selangor, Malaysia
| | - M. Y. Rafii
- Institute of Tropical Agriculture, Universiti Putra Malaysia, 43400 UPM, Serdang, Selangor, Malaysia
| | - A. R. Anuar
- Department of Land Management, Faculty of Agriculture, Universiti Putra Malaysia, 43400 UPM, Serdang, Selangor, Malaysia
| | - S. A. Sheikh Awadz
- Department of Crop Science, Faculty of Agriculture, Universiti Putra Malaysia, 43400 UPM, Serdang, Selangor, Malaysia
| | - M. P. Anwar
- Institute of Tropical Agriculture, Universiti Putra Malaysia, 43400 UPM, Serdang, Selangor, Malaysia
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17
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He LS, Meng FL, Diao XJ, Li YW, Meng R, Xi BD, Shu JM. [Allelopathic effect of Nelumbo nucifera stem and leaf tissue extract on the growth of Microcystis aeruginosa and Scenedesmus quadricanda]. Huan Jing Ke Xue 2013; 34:2637-2641. [PMID: 24027993] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 06/02/2023]
Abstract
Effects of Nelumbo nucifera stem and leaf tissue extract on the growth of Microcystis aeruginosa and Scenedesmus quadricanda were studied to verify its potential in entriphication control. Five concentrations of Nelumbo nucifera stem and leaf tissue extract were chosen to compare their inhibitory effects on the growth of Microcystis aeruginosa and Scenedesmus quadricanda. The result showed that the leaf extract inhibited the algae bloom more effectively than the stem extract on the whole. When the leaf extract normality was 25 g x L(-1), the highest inhibition rate of Microcystis aeruginosa and Scenedesmus quadricanda was 71.33% and 78.14%, respectively, while for the stem extract, the values were 49.78% and 52.14%. Propanamide was found in both the stem and leaf tissue extracts of Nelumbo nucifera by GC-MS analysis, with concentrations of 1.1 mg x L(-1) and 0.2 mg x L(-1), respectively. The EC50 values of the two kinds of algae were calculated by the probability method.
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Affiliation(s)
- Lian-Sheng He
- Chinese Research Academy of Environmental Sciences, Beijing 100012, China.
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18
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Zhao J, Xue QH, Du JZ, Chen JJ. [Identification of two Fusarium isolates and their crude toxin allelopathic effect on Cucumis melo seedlings]. Ying Yong Sheng Tai Xue Bao 2013; 24:142-148. [PMID: 23718002] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 06/02/2023]
Abstract
Eight fungi isolates were obtained from Fusarium-infected Cucumis melo (melon) plants and their rhizosphere soils. Taking melon cultivar 'Xitian 1' as test material, the re-inoculation and seed germination experiments were conducted to investigate the pathogenicity and growth inhibition effect of these fungi isolates on melon. Through the determination of the induced enzyme activities, resistant substance contents, and cell membrane permeability of potted melon roots, the allelopathic effect of the crude toxins of two harmful fungi was studied, and according to the morphological characteristics and Internal Transcribed Spacer (ITS) sequencing, the two harmful fungi were identified. The crude toxins of the two harmful fungi TF and HF had strong inhibition effects on the germination and growth of the melon seeds. The MDA and soluble protein contents and the cell membrane permeability of the 'Xitian 1' seedlings roots all increased, among which, the MDA content and cell membrane permeability increased by 108.6% and 40.6%, respectively when treated with the stock solution of TF toxin, compared with the control. The crude toxins of the two harmful fungi improved the induced enzyme activities of the melon roots, with the increment of the PAL and POD activities under the treatment of 10-fold dilution of TF crude toxin increased by 25.6% and 23.2%, respectively. When treated with the stock solution of HF toxin, the PAL activity significantly increased by 30.0%. The two harmful fungi TF and HF were primarily identified as Fusarium equisti and F. proliferatum, respectively. This study showed that the two Fusarium isolates could not infect melon via re-inoculation, but could negatively affect the melon's normal growth and normal physiological and biochemical metabolism via toxins excretion, and in the meantime, improve the root protective enzyme activities, with the effects of both benefit and harmfulness on melon plants. The allelopathic hazard of the crude toxins of the isolates could be one of the main causes of continuous cropping obstacle of melon.
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Affiliation(s)
- Juan Zhao
- College of Life Sciences, Northwest A&F University, Yangling 712100, Shaanxi, China.
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