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Bjerring Jensen N, Vrobel O, Akula Nageshbabu N, De Diego N, Tarkowski P, Ottosen CO, Zhou R. Stomatal effects and ABA metabolism mediate differential regulation of leaf and flower cooling in tomato cultivars exposed to heat and drought stress. JOURNAL OF EXPERIMENTAL BOTANY 2024; 75:2156-2175. [PMID: 38207009 DOI: 10.1093/jxb/erad498] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/06/2023] [Accepted: 01/09/2024] [Indexed: 01/13/2024]
Abstract
Co-occurring heat and drought stresses challenge crop performance. Stomata open to promote evaporative cooling during heat stress, but close to retain water during drought stress, which resulted in complex stomatal regulation under combined heat and drought. We aimed to investigate stomatal regulation in leaves and flowers of perennial, indeterminate cultivars of tomatoes subjected to individual and combined heat and drought stress followed by a recovery period, measuring morphological, physiological, and biochemical factors involved in stomatal regulation. Under stress, stomata of leaves were predominantly affected by drought, with lower stomatal density and stomatal closing, resulting in significantly decreased photosynthesis and higher leaf temperature. Conversely, stomata in sepals seemed affected mainly by heat during stress. The differential patterns in stomatal regulation in leaves and flowers persisted into the recovery phase as contrasting patterns in stomatal density. We show that flower transpiration is regulated by temperature, but leaf transpiration is regulated by soil water availability during stress. Organ-specific patterns of stomatal development and abscisic acid metabolism mediated this phenomenon. Our results throw light on the dual role of stomata in heat and drought tolerance of vegetative and generative organs, and demonstrate the importance of considering flower surfaces in the phenotyping of stomatal reactions to stress.
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Affiliation(s)
- Nikolaj Bjerring Jensen
- Department of Food Science, Plant, Food & Climate, Aarhus University, Agro Food Park 48, DK-8200, Aarhus N, Denmark
| | - Ondřej Vrobel
- Czech Advanced Technology and Research Institute, Palacky University, Šlechtitelů 27, 78371 Olomouc, Czech Republic
- Centre of the Region Haná for Biotechnological and Agricultural Research, Department of Genetic Resources for Vegetables, Medicinal and Special Plants, Crop Research Institute, Šlechtitelů 29, 78371 Olomouc, Czech Republic
| | - Nagashree Akula Nageshbabu
- Department of Food Science, Plant, Food & Climate, Aarhus University, Agro Food Park 48, DK-8200, Aarhus N, Denmark
| | - Nuria De Diego
- Czech Advanced Technology and Research Institute, Palacky University, Šlechtitelů 27, 78371 Olomouc, Czech Republic
| | - Petr Tarkowski
- Czech Advanced Technology and Research Institute, Palacky University, Šlechtitelů 27, 78371 Olomouc, Czech Republic
- Centre of the Region Haná for Biotechnological and Agricultural Research, Department of Genetic Resources for Vegetables, Medicinal and Special Plants, Crop Research Institute, Šlechtitelů 29, 78371 Olomouc, Czech Republic
| | - Carl-Otto Ottosen
- Department of Food Science, Plant, Food & Climate, Aarhus University, Agro Food Park 48, DK-8200, Aarhus N, Denmark
| | - Rong Zhou
- Department of Food Science, Plant, Food & Climate, Aarhus University, Agro Food Park 48, DK-8200, Aarhus N, Denmark
- College of Horticulture, Nanjing Agricultural University, Nanjing 210095, China
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Ahouvi Y, Haber Z, Zach YY, Rosental L, Toubiana D, Sharma D, Alseekh S, Tajima H, Fernie AR, Brotman Y, Blumwald E, Sade N. The Alteration of Tomato Chloroplast Vesiculation Positively Affects Whole-Plant Source-Sink Relations and Fruit Metabolism under Stress Conditions. PLANT & CELL PHYSIOLOGY 2023; 63:2008-2026. [PMID: 36161338 DOI: 10.1093/pcp/pcac133] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/22/2022] [Revised: 09/14/2022] [Accepted: 09/23/2022] [Indexed: 06/16/2023]
Abstract
Changes in climate conditions can negatively affect the productivity of crop plants. They can induce chloroplast degradation (senescence), which leads to decreased source capacity, as well as decreased whole-plant carbon/nitrogen assimilation and allocation. The importance, contribution and mechanisms of action regulating source-tissue capacity under stress conditions in tomato (Solanum lycopersicum) are not well understood. We hypothesized that delaying chloroplast degradation by altering the activity of the tomato chloroplast vesiculation (CV) under stress would lead to more efficient use of carbon and nitrogen and to higher yields. Tomato CV is upregulated under stress conditions. Specific induction of CV in leaves at the fruit development stage resulted in stress-induced senescence and negatively affected fruit yield, without any positive effects on fruit quality. Clustered Regularly Interspaced Short Palindromic Repeats/CRISPR-associated protein 9 (CRISPR/CAS9) knockout CV plants, generated using a near-isogenic tomato line with enhanced sink capacity, exhibited stress tolerance at both the vegetative and the reproductive stages, leading to enhanced fruit quantity, quality and harvest index. Detailed metabolic and transcriptomic network analysis of sink tissue revealed that the l-glutamine and l-arginine biosynthesis pathways are associated with stress-response conditions and also identified putative novel genes involved in tomato fruit quality under stress. Our results are the first to demonstrate the feasibility of delayed stress-induced senescence as a stress-tolerance trait in a fleshy fruit crop, to highlight the involvement of the CV pathway in the regulation of source strength under stress and to identify genes and metabolic pathways involved in increased tomato sink capacity under stress conditions.
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Affiliation(s)
- Yoav Ahouvi
- School of Plant Sciences and Food Security, Tel Aviv University, P.O.B. 39040, 55 Haim Levanon St., Tel Aviv 6139001, Israel
| | - Zechariah Haber
- School of Plant Sciences and Food Security, Tel Aviv University, P.O.B. 39040, 55 Haim Levanon St., Tel Aviv 6139001, Israel
| | - Yair Yehoshua Zach
- School of Plant Sciences and Food Security, Tel Aviv University, P.O.B. 39040, 55 Haim Levanon St., Tel Aviv 6139001, Israel
| | - Leah Rosental
- Department of Life Sciences, Ben-Gurion University of the Negev, P.O.B. 653, 1 David Ben Gurion Blvd., Beer-Sheva 8410501, Israel
| | - David Toubiana
- School of Plant Sciences and Food Security, Tel Aviv University, P.O.B. 39040, 55 Haim Levanon St., Tel Aviv 6139001, Israel
| | - Davinder Sharma
- School of Plant Sciences and Food Security, Tel Aviv University, P.O.B. 39040, 55 Haim Levanon St., Tel Aviv 6139001, Israel
| | - Saleh Alseekh
- Department of Root Biology and Symbiosis, Max Planck Institute of Molecular Plant Physiology, 1 Am Mühlenberg, Golm, Potsdam 14476, Germany
- Department of Plant Metabolomics, Center for Plant Systems Biology and Biotechnology, 139 Ruski Blvd., Plovdiv 4000, Bulgaria
| | - Hiromi Tajima
- Department of Plant Sciences, University of California, 1 Shields Ave., Davis, CA 95616, USA
| | - Alisdair R Fernie
- Department of Root Biology and Symbiosis, Max Planck Institute of Molecular Plant Physiology, 1 Am Mühlenberg, Golm, Potsdam 14476, Germany
- Department of Plant Metabolomics, Center for Plant Systems Biology and Biotechnology, 139 Ruski Blvd., Plovdiv 4000, Bulgaria
| | - Yariv Brotman
- Department of Life Sciences, Ben-Gurion University of the Negev, P.O.B. 653, 1 David Ben Gurion Blvd., Beer-Sheva 8410501, Israel
| | - Eduardo Blumwald
- Department of Plant Sciences, University of California, 1 Shields Ave., Davis, CA 95616, USA
| | - Nir Sade
- School of Plant Sciences and Food Security, Tel Aviv University, P.O.B. 39040, 55 Haim Levanon St., Tel Aviv 6139001, Israel
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Zhao R, Zhang H, An L. Plant size influences abundance of floral visitors and biomass allocation for the cushion plant Thylacospermum caespitosum under an extreme alpine environment. Ecol Evol 2019; 9:5501-5511. [PMID: 31110698 PMCID: PMC6509400 DOI: 10.1002/ece3.5147] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2017] [Revised: 03/18/2019] [Accepted: 03/18/2019] [Indexed: 01/18/2023] Open
Abstract
Variation in size may influence the abundance of visitors and reproductive allocation for cushion plants in the extreme alpine environments. To assess effects of plant size on the abundance of main visitors and reproductive allocation in Thylacospermum caespitosum populations at two altitudes, the abundance of the visitors, visiting frequency, total number of flowers, number of fruits, number of unseeded flowers, and reproductive allocation were investigated during the period of reproductive growth. Concurrently, the effects of plant size on the visitors' contributions to fruit setting rate were assessed by a bagging experiment. Our results showed that flies (Musca domestica and Dasyphora asiatica) were the main pollinating insects of T. caespitosum, and they could obvious facilitate (p < 0.05) the fruit setting rate of this cushion plant. Seed set and floral visitation were significantly influenced (p < 0.001) by plant size. Moreover, the reproductive allocation and fruit setting rate of T. caespitosum was influenced (p < 0.001) by plant size. More biomass was allocated to reproduction in plants of greater diameter. There is an increase in reproductive success (increases of fruit number with increase in plant size) in relation to plant size. In conclusion, the extent of M. domestica and D. asiatica to facilitate the fruit setting rate mainly depended on the size of T. caespitosum. Size-dependent reproductive allocation occurred in T. caespitosum and was the chief factor affecting the contribution of flies to fruit setting rate. These traits reflect reproductive fitness of T. caespitosum related to plant size in extreme alpine environments.
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Affiliation(s)
- Ruiming Zhao
- MOE Key Laboratory of Cell Activities and Stress AdaptationsSchool of Life SciencesLanzhou UniversityLanzhouChina
| | - Hua Zhang
- MOE Key Laboratory of Cell Activities and Stress AdaptationsSchool of Life SciencesLanzhou UniversityLanzhouChina
| | - Lizhe An
- The College of ForestryBeijing Forestry UniversityBeijingChina
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Sade N, Del Mar Rubio-Wilhelmi M, Umnajkitikorn K, Blumwald E. Stress-induced senescence and plant tolerance to abiotic stress. JOURNAL OF EXPERIMENTAL BOTANY 2018; 69:845-853. [PMID: 28992323 DOI: 10.1093/jxb/erx235] [Citation(s) in RCA: 113] [Impact Index Per Article: 18.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/10/2017] [Accepted: 06/14/2017] [Indexed: 05/20/2023]
Abstract
Senescence is an age-dependent process, ultimately leading to plant death, that in annual crop plants overlaps with the reproductive stage of development. Research on the molecular and biochemical mechanisms of leaf senescence has revealed a multi-layered regulatory network operating to control age-dependent processes. Abiotic stress-induced senescence challenges source-sink relationships and results in significant reduction in crop yields. Although processes associated with plant senescence are well studied, the mechanisms regulating stress-induced senescence are not well known. Here, we discuss the effects of abiotic stress on crop productivity, mechanisms associated with stress-induced senescence, and the possible use of these mechanisms for the generation of plant stress tolerance. We emphasize the involvement of source strength and stability of the photosynthetic apparatus in this process, and suggest a possible role of a perennial plant life strategy for the amelioration of stress-induced senescence.
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Affiliation(s)
- Nir Sade
- Department of Plant Sciences, University of California, Davis, CA, USA
| | | | | | - Eduardo Blumwald
- Department of Plant Sciences, University of California, Davis, CA, USA
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Mao W, Felton AJ, Zhang T. Linking Changes to Intraspecific Trait Diversity to Community Functional Diversity and Biomass in Response to Snow and Nitrogen Addition Within an Inner Mongolian Grassland. FRONTIERS IN PLANT SCIENCE 2017; 8:339. [PMID: 28352278 PMCID: PMC5348515 DOI: 10.3389/fpls.2017.00339] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/10/2017] [Accepted: 02/27/2017] [Indexed: 05/28/2023]
Abstract
In recent years, both the intraspecific and interspecific functional diversity (FD) of plant communities have been studied with new approaches to improve an understanding about the mechanisms underlying plant species coexistence. Yet, little is known about how global change drivers will impact intraspecific FD and trait overlap among species, and in particular how this may scale to impacts on community level FD and ecosystem functioning. To address this uncertainty, we assessed the direct and indirect responses of specific leaf area (SLA) among both dominant annual and subordinate perennial species to the independent and interactive effects of nitrogen and snow addition within the Inner Mongnolian steppe. More specifically, we investigated the consequences for these responses on plant community FD, trait overlap and biomass. Nitrogen addition increased the biomass of the dominant annual species and as a result increased total community biomass. This occurred despite concurrent decreases in the biomass of subordinate perennial species. Nitrogen addition also increased intraspecific FD and trait overlap of both annual species and perennial species, and consequently increased the degree of trait overlap in SLA at the community level. However, snow addition did not significantly impact intraspecific FD and trait overlap of SLA for perennial species, but increased intraspecific FD and trait overlap of annual species, of which scaled to changes in community level FD. We found that the responses of the dominant annual species to nitrogen and snow additions were generally more sensitive than the subordinate perennial species within the inner Mongolian grassland communities of our study. As a consequence of this sensitivity, the responses of the dominant species largely drove impacts to community FD, trait overlap and community biomass. In total, our study demonstrates that the responses of dominant species in a community to environmental change may drive the initial trajectories of change to community FD and functioning.
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Affiliation(s)
- Wei Mao
- Northwest Institute of Eco-Environment and Resource, Chinese Academy of SciencesLanzhou, China
- Department of Biology and Graduate Degree Program in Ecology, Colorado State University, Fort CollinsCO, USA
| | - Andrew J. Felton
- Department of Biology and Graduate Degree Program in Ecology, Colorado State University, Fort CollinsCO, USA
| | - Tonghui Zhang
- Northwest Institute of Eco-Environment and Resource, Chinese Academy of SciencesLanzhou, China
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Jaikumar NS, Snapp SS, Sharkey TD. Life history and resource acquisition: Photosynthetic traits in selected accessions of three perennial cereal species compared with annual wheat and rye. AMERICAN JOURNAL OF BOTANY 2013; 100:2468-2477. [PMID: 24322893 DOI: 10.3732/ajb.1300122] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
PREMISE OF THE STUDY Few previous studies have considered how plant age affects photosynthetic physiology in herbaceous perennials or how photosynthetic capacity in annual cereals compares to perennial relatives. Newly developed perennial cereals offer novel systems for addressing these questions. Our study makes a novel contribution by considering how life history differences affect photosynthetic physiology. METHODS In two linked field studies, we evaluated effects of life history and plant age on photosynthetic rates (A), and related biochemical, morphological, and water-relations traits, comparing 1- and 2-yr-old cohorts of perennial wheat, intermediate wheatgrass, and perennial rye to close annual relatives (wheat and rye). KEY RESULTS Photosynthetic rates (A) were 10-50% higher in perennial cereals compared to annuals. In wheatgrass, elevated A was associated with higher carboxylation (VC), triose phosphate utilization (TPU) and electron transport rates (J), and higher leaf soluble protein and chlorophyll. Younger wheatgrass plants maintained higher A, TPU, J, and VC than older plants did. Perennial wheat and rye differed from annual relatives in some but not all of these parameters. Differences in stomatal limitation were not involved, while differences in stomatal conductance (gs) became evident under drier conditions. CONCLUSIONS This study demonstrates that some perennial cereal species can maintain higher midseason A than their annual crop relatives. These changes are not fully explainable by increased access to soil water and may reflect trade-offs between allocation to reproduction and to resource acquisition. We also found evidence for age-related changes in photosynthetic physiology in a herbaceous perennial plant.
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Affiliation(s)
- Nikhil S Jaikumar
- Department of Plant, Soil and Microbial Science, Michigan State University, East Lansing, Michigan USA
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Ye X, Sakai K. Limited and time-delayed internal resource allocation generates oscillations and chaos in the dynamics of citrus crops. CHAOS (WOODBURY, N.Y.) 2013; 23:043124. [PMID: 24387563 DOI: 10.1063/1.4832617] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
Alternate bearing or masting is a yield variability phenomenon in perennial crops. The complex dynamics in this phenomenon have stimulated much ecological research. Motivated by data from an eight-year experiment with forty-eight individual trees, we explored the mechanism inherent to these dynamics in Satsuma mandarin (Citrus unshiu Marc.). By integrating high-resolution imaging technology, we found that the canopy structure and reproduction output of individual citrus crops are mutually dependent on each other. Furthermore, it was revealed that the mature leaves in early season contribute their energy to the fruiting of the current growing season, whereas the younger leaves show a delayed contribution to the next growing season. We thus hypothesized that the annual yield variability might be caused by the limited and time-delayed resource allocation in individual plants. A novel lattice model based on this hypothesis demonstrates that this pattern of resource allocation will generate oscillations and chaos in citrus yield.
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Affiliation(s)
- Xujun Ye
- College of Biosystems Engineering and Food Science, Zhejiang University, Hangzhou 310058, China
| | - Kenshi Sakai
- Environmental & Agricultural Engineering Department, Tokyo University of Agriculture and Technology, Tokyo 183-8509, Japan
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Comas LH, Becker SR, Cruz VMV, Byrne PF, Dierig DA. Root traits contributing to plant productivity under drought. FRONTIERS IN PLANT SCIENCE 2013. [PMID: 24204374 DOI: 10.3389/fenvs.2014.00442] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Indexed: 05/16/2023]
Abstract
Geneticists and breeders are positioned to breed plants with root traits that improve productivity under drought. However, a better understanding of root functional traits and how traits are related to whole plant strategies to increase crop productivity under different drought conditions is needed. Root traits associated with maintaining plant productivity under drought include small fine root diameters, long specific root length, and considerable root length density, especially at depths in soil with available water. In environments with late season water deficits, small xylem diameters in targeted seminal roots save soil water deep in the soil profile for use during crop maturation and result in improved yields. Capacity for deep root growth and large xylem diameters in deep roots may also improve root acquisition of water when ample water at depth is available. Xylem pit anatomy that makes xylem less "leaky" and prone to cavitation warrants further exploration holding promise that such traits may improve plant productivity in water-limited environments without negatively impacting yield under adequate water conditions. Rapid resumption of root growth following soil rewetting may improve plant productivity under episodic drought. Genetic control of many of these traits through breeding appears feasible. Several recent reviews have covered methods for screening root traits but an appreciation for the complexity of root systems (e.g., functional differences between fine and coarse roots) needs to be paired with these methods to successfully identify relevant traits for crop improvement. Screening of root traits at early stages in plant development can proxy traits at mature stages but verification is needed on a case by case basis that traits are linked to increased crop productivity under drought. Examples in lesquerella (Physaria) and rice (Oryza) show approaches to phenotyping of root traits and current understanding of root trait genetics for breeding.
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Affiliation(s)
- Louise H Comas
- Water Management Research, United States Department of Agriculture-Agricultural Research Service Fort Collins, CO, USA
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Comas LH, Becker SR, Cruz VMV, Byrne PF, Dierig DA. Root traits contributing to plant productivity under drought. FRONTIERS IN PLANT SCIENCE 2013; 4:442. [PMID: 24204374 PMCID: PMC3817922 DOI: 10.3389/fpls.2013.00442] [Citation(s) in RCA: 451] [Impact Index Per Article: 41.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/11/2013] [Accepted: 10/15/2013] [Indexed: 05/17/2023]
Abstract
Geneticists and breeders are positioned to breed plants with root traits that improve productivity under drought. However, a better understanding of root functional traits and how traits are related to whole plant strategies to increase crop productivity under different drought conditions is needed. Root traits associated with maintaining plant productivity under drought include small fine root diameters, long specific root length, and considerable root length density, especially at depths in soil with available water. In environments with late season water deficits, small xylem diameters in targeted seminal roots save soil water deep in the soil profile for use during crop maturation and result in improved yields. Capacity for deep root growth and large xylem diameters in deep roots may also improve root acquisition of water when ample water at depth is available. Xylem pit anatomy that makes xylem less "leaky" and prone to cavitation warrants further exploration holding promise that such traits may improve plant productivity in water-limited environments without negatively impacting yield under adequate water conditions. Rapid resumption of root growth following soil rewetting may improve plant productivity under episodic drought. Genetic control of many of these traits through breeding appears feasible. Several recent reviews have covered methods for screening root traits but an appreciation for the complexity of root systems (e.g., functional differences between fine and coarse roots) needs to be paired with these methods to successfully identify relevant traits for crop improvement. Screening of root traits at early stages in plant development can proxy traits at mature stages but verification is needed on a case by case basis that traits are linked to increased crop productivity under drought. Examples in lesquerella (Physaria) and rice (Oryza) show approaches to phenotyping of root traits and current understanding of root trait genetics for breeding.
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Affiliation(s)
- Louise H. Comas
- Water Management Research, United States Department of Agriculture-Agricultural Research ServiceFort Collins, CO, USA
| | - Steven R. Becker
- Department of Soil and Crop Sciences, Colorado State UniversityFort Collins, CO, USA
| | - Von Mark V. Cruz
- National Center for Genetic Resources Preservation, United States Department of Agriculture-Agricultural Research ServiceFort Collins, CO, USA
- Bioagricultural Sciences and Pest Management, Colorado State UniversityFort Collins, CO, USA
| | - Patrick F. Byrne
- Department of Soil and Crop Sciences, Colorado State UniversityFort Collins, CO, USA
| | - David A. Dierig
- National Center for Genetic Resources Preservation, United States Department of Agriculture-Agricultural Research ServiceFort Collins, CO, USA
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Van Tassel DL, DeHaan LR, Cox TS. Missing domesticated plant forms: can artificial selection fill the gap? Evol Appl 2010; 3:434-52. [PMID: 25567937 PMCID: PMC3352511 DOI: 10.1111/j.1752-4571.2010.00132.x] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/02/2010] [Accepted: 04/12/2010] [Indexed: 11/26/2022] Open
Abstract
In the course of their evolution, the angiosperms have radiated into most known plant forms and life histories. Their adaptation to a recently created habitat, the crop field, produced a novel form: the plant that allocates an unprecedented 30-60% of its net productivity to sexual structures. Long-lived trees, shrubs and vines of this form evolved, as did annual herbs. Perennial herb forms with increased allocation to asexual reproduction evolved, but there are no examples of perennial herbs with high sexual effort. We suggest that sowing seed into annually tilled fields favored shorter-lived herbs because of trade-offs between first-year seed production and relative growth rate and/or persistence. By propagating cuttings, people quickly domesticated tuber crops and large woody plants. Perennial herbs were too small to be efficiently propagated by cuttings, and the association between longevity, allogamy and genetic load made rapid domestication by sexual cycles unlikely. Perennial grain crops do not exist because they could not have evolved under the original set of conditions; however, they can be deliberately developed today through artificial phenotypic and genotypic selection.
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Cella Pizarro L, Bisigato AJ. Allocation of biomass and photoassimilates in juvenile plants of six Patagonian species in response to five water supply regimes. ANNALS OF BOTANY 2010; 106:297-307. [PMID: 20519238 PMCID: PMC2908164 DOI: 10.1093/aob/mcq109] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/12/2009] [Revised: 01/28/2010] [Accepted: 04/23/2010] [Indexed: 05/23/2023]
Abstract
BACKGROUND AND AIMS The growth-differentiation balance hypothesis (GDBH) states that there is a physiological trade-off between growth and secondary metabolism and predicts a parabolic effect of resource availability (such as water or nutrients) on secondary metabolite production. To test this hypothesis, the response of six Patagonian Monte species (Jarava speciosa, Grindelia chiloensis, Prosopis alpataco, Bougainvillea spinosa, Chuquiraga erinacea and Larrea divaricata) were investigated in terms of total biomass and resource allocation patterns in response to a water gradient. METHODS One-month-old seedlings were subjected to five water supply regimes (expressed as percentage dry soil weight: 13 %, 11 %, 9 %, 7 % or 5 % - field water capacity being 15 %). After 150 d, plants were harvested, oven-dried and partitioned into root, stem and leaf. Allometric analysis was used to correct for size differences in dry matter partitioning. Determinations of total phenolics (TP), condensed tannins (CT), nitrogen (N) and total non-structural carbohydrates (TNC) concentrations were done on each fraction. Based on concentrations and biomass data, contents of TP and CT were estimated for whole plants, and graphical vector analysis was applied to interpret drought effect. KEY RESULTS Four species (J. speciosa, G. chiloensis, P. alpataco and B. spinosa) showed a decrease in total biomass in the 5 % water supply regime. Differences in dry matter partitioning among treatments were mainly due to size variation. Concentrations of TP, CT, N and TNC varied little and the effect of drought on contents of TP and CT was not adequately predicted by the GDBH, except for G. chiloensis. CONCLUSIONS Water stress affected growth-related processes (i.e. reduced total biomass) rather than defence-related secondary metabolism or allocation to different organs in juvenile plants. Therefore, the results suggest that application of the GDBH to plants experiencing drought-stress should be done with caution, at least for Patagonian Monte species.
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Glover JD, Reganold JP, Bell LW, Borevitz J, Brummer EC, Buckler ES, Cox CM, Cox TS, Crews TE, Culman SW, DeHaan LR, Eriksson D, Gill BS, Holland J, Hu F, Hulke BS, Ibrahim AMH, Jackson W, Jones SS, Murray SC, Paterson AH, Ploschuk E, Sacks EJ, Snapp S, Tao D, Van Tassel DL, Wade LJ, Wyse DL, Xu Y. Increased Food and Ecosystem Security via Perennial Grains. Science 2010; 328:1638-9. [DOI: 10.1126/science.1188761] [Citation(s) in RCA: 312] [Impact Index Per Article: 22.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/02/2022]
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