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Zhou XR, Zhang NN, Zhao YM, Dai L, Xu DP, Xu GF, Tian J. Distribution Dynamics and Roles of Starch in Non-photosynthetic Vegetative Organs of Santalum album Linn., a Hemiparasitic Tree. FRONTIERS IN PLANT SCIENCE 2021; 11:532537. [PMID: 33584738 PMCID: PMC7873954 DOI: 10.3389/fpls.2020.532537] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 02/04/2020] [Accepted: 12/16/2020] [Indexed: 06/12/2023]
Abstract
Allocation dynamics of stored starch plays essential roles in the development and growth of trees. Previous studies focused on the dynamics and the characteristics of starch in autotrophic trees. However, although starch granules have been detected in the organs or tissues of some parasitic plants, studies on the allocation dynamics and roles of storage starch in them are limited. Therefore, we determined and estimated the allocation dynamics and roles of starch in Santalum album Linn., a hemiparasitic tree, using morphological and physiological methods. Our findings showed abundant starch in the stem and root of S. album at the early seedling stage. Although S. album seedlings attached to the host showed no significant changes in starch levels throughout the experiment, unattached and host-removed seedlings exhibited a gradual decrease in the starch content over time. When the starch content of unattached seedlings was less than 1%, they started to die. Starch accumulated to high levels in developing and active haustoria; however, starch levels were low in the inactive haustoria. The present study suggests that starch may provide energy to seedlings that have no host, allowing them to survive during the unattached phase, thus increasing their chance to attach to host roots by extending their survival duration. In addition, we speculate that storage starch is potentially involved in the development of haustoria and in the physiological processes of S. album related to the absorption and transportation of water and nutrients from its host.
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Affiliation(s)
- Xiu Ren Zhou
- School of Life Science and Technology, Henan Institute of Science and Technology, Xinxiang, China
| | - Ning Nan Zhang
- Research Institute of Tropical Forestry, Chinese Academy of Forestry, Guangzhou, China
| | - Yi Min Zhao
- Guangxi Botanical Garden of Medicinal Plants, Nanning, China
| | - Lei Dai
- School of Life Science and Technology, Henan Institute of Science and Technology, Xinxiang, China
| | - Da Ping Xu
- Research Institute of Tropical Forestry, Chinese Academy of Forestry, Guangzhou, China
| | - Gui Fang Xu
- School of Life Science and Technology, Henan Institute of Science and Technology, Xinxiang, China
| | - Jing Tian
- School of Life Science and Technology, Henan Institute of Science and Technology, Xinxiang, China
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Luo X, Zhang Y, Wu H, Bai J. Drought stress-induced autophagy gene expression is correlated with carbohydrate concentrations in Caragana korshinskii. PROTOPLASMA 2020; 257:1211-1220. [PMID: 32318821 DOI: 10.1007/s00709-020-01507-y] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/11/2019] [Accepted: 03/29/2020] [Indexed: 06/11/2023]
Abstract
Autophagy has been reported to be an adapt function of plant cells under various stresses. In this report, autophagy-related gene expressions and carbohydrate concentrations in Caragana korshinskii leaf cells under drought stress were investigated. Leaf samples of C. korshinskii plants of an estimated 15-year-old were collected from three sites with different drought stress (annual precipitation range, 325.8 to 440.8 mm) at the Loess Plateau in northwestern China. Autophagy was observed in C. korshinskii samples from all three sites and was revealed by autophagosomes in the cytoplasm of mesophyll cells and increased chloroplasts degradation observed by transmission electron microscopy. Furthermore, with the drought stress increase, autophagy-related gene expressions were upregulated and leaf concentration of sucrose was increased, while concentrations of monosaccharide sugars such as glucose, fructose and galactose were decreased. The results suggested that drought stress induced autophagy gene expression, which may serve as a survival mechanism for nutrient remobilisation.
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Affiliation(s)
- Xinjuan Luo
- College of Life Sciences, Northwest A&F University, Yangling, 712100, Shaanxi, China
| | - Yanyu Zhang
- College of Sciences, Northwest A&F University, 712100, Yangling, Shaanxi, China
| | - Hongdou Wu
- College of Life Sciences, Northwest A&F University, Yangling, 712100, Shaanxi, China
| | - Juan Bai
- College of Horticulture, Northwest A&F University, 712100, Yangling, Shaanxi, China.
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Molecular Evaluation of Vitality and Survival Rate of Dormant Kyoho Grape Seedlings: A Step toward Molecular Farming. PLANTS 2019; 8:plants8120577. [PMID: 31817601 PMCID: PMC6963589 DOI: 10.3390/plants8120577] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 10/29/2019] [Revised: 11/27/2019] [Accepted: 11/28/2019] [Indexed: 12/18/2022]
Abstract
Vitality and survival rate of grape seedlings are crucial factors affecting quality of vineyards. There is no comprehensive study describing accurate evaluation of dormant grapevine seedlings’ vitality and survival rate. The purpose of this study was to explore the possibility of using molecular information to evaluate viability and survival rate of dormant seedlings before transplanting. After bare roots treatment, 1–5 day expression levels of six HKGs in four buds of tetraploid Kyoho grape (Vitis labruscana: V. labrusca × V. vinifera) seedlings were detected by (Sq.) RT-PCR and qRT-PCR for calibration of the molecular method. The results revealed that HKGs expression indicates vitality and survival of plant, higher expression was strongly linked to higher vitality and survival rate, lower expression was associated with lower vitality, and lowest expression was significantly associated with lowest vitality and survival rate. Moreover, DNA and RNA quality can superficially determine seedling qualities. Finally, the survival rate of the seedlings produced in Juxian-Shandong, Laixi-Shandong, Huailai-Hebei, Suizhong-Liaoning, Changli-Hebei, Guanxian-Shandong, and Zhangjiagang-Jiangsu was 100.00%, 100.00%, 100.00%, 100.00%, 100.00%, 87.77%, and 93.33%, respectively. In conclusion, molecular technique is potential approach for promoting gene information to estimate vitality and survival rate of dormant grape seedlings and might contribute to viticulturists’ efforts.
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Li W, Hartmann H, Adams HD, Zhang H, Jin C, Zhao C, Guan D, Wang A, Yuan F, Wu J. The sweet side of global change-dynamic responses of non-structural carbohydrates to drought, elevated CO2 and nitrogen fertilization in tree species. TREE PHYSIOLOGY 2018; 38:1706-1723. [PMID: 29897549 DOI: 10.1093/treephys/tpy059] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/08/2018] [Accepted: 05/02/2018] [Indexed: 06/08/2023]
Abstract
Non-structural carbohydrates (NSC) play a central role in plant functioning as energy carriers and building blocks for primary and secondary metabolism. Many studies have investigated how environmental and anthropogenic changes, like increasingly frequent and severe drought episodes, elevated CO2 and atmospheric nitrogen (N) deposition, influence NSC concentrations in individual trees. However, this wealth of data has not been analyzed yet to identify general trends using a common statistical framework. A thorough understanding of tree responses to global change is required for making realistic predictions of vegetation dynamics. Here we compiled data from 57 experimental studies on 71 tree species and conducted a meta-analysis to evaluate general responses of stored soluble sugars, starch and total NSC (soluble sugars + starch) concentrations in different tree organs (foliage, above-ground wood and roots) to drought, elevated CO2 and N deposition. We found that drought significantly decreased total NSC in roots (-17.3%), but not in foliage and above-ground woody tissues (bole, branch, stem and/or twig). Elevated CO2 significantly increased total NSC in foliage (+26.2%) and roots (+12.8%), but not in above-ground wood. By contrast, total NSC significantly decreased in roots (-17.9%), increased in above-ground wood (+6.1%), but was unaffected in foliage from N fertilization. In addition, the response of NSC to three global change drivers was strongly affected by tree taxonomic type, leaf habit, tree age and treatment intensity. Our results pave the way for a better understanding of general tree function responses to drought, elevated CO2 and N fertilization. The existing data also reveal that more long-term studies on mature trees that allow testing interactions between these factors are urgently needed to provide a basis for forecasting tree responses to environmental change at the global scale.
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Affiliation(s)
- Weibin Li
- State Key Laboratory of Grassland and Agro-ecosystems, Key Laboratory of Grassland Livestock Industry Innovation, Ministry of Agriculture and Rural Affairs, College of Pastoral Agriculture Science and Technology, Lanzhou University, Lanzhou, China
| | - Henrik Hartmann
- Max-Planck Institute for Biogeochemistry, Hans Knöll Str. 10, Jena, Germany
| | - Henry D Adams
- Department of Plant Biology, Ecology and Evolution, Oklahoma State University, Stillwater, OK, USA
| | - Hongxia Zhang
- Key Laboratory of Forest Ecology and Management, Institute of Applied Ecology, Chinese Academy of Sciences, Shenyang, China
- University of Chinese Academy of Sciences, Beijing, China
| | - Changjie Jin
- Key Laboratory of Forest Ecology and Management, Institute of Applied Ecology, Chinese Academy of Sciences, Shenyang, China
| | - Chuanyan Zhao
- State Key Laboratory of Grassland and Agro-ecosystems, Key Laboratory of Grassland Livestock Industry Innovation, Ministry of Agriculture and Rural Affairs, College of Pastoral Agriculture Science and Technology, Lanzhou University, Lanzhou, China
| | - Dexin Guan
- Key Laboratory of Forest Ecology and Management, Institute of Applied Ecology, Chinese Academy of Sciences, Shenyang, China
| | - Anzhi Wang
- Key Laboratory of Forest Ecology and Management, Institute of Applied Ecology, Chinese Academy of Sciences, Shenyang, China
| | - Fenghui Yuan
- Key Laboratory of Forest Ecology and Management, Institute of Applied Ecology, Chinese Academy of Sciences, Shenyang, China
| | - Jiabing Wu
- Key Laboratory of Forest Ecology and Management, Institute of Applied Ecology, Chinese Academy of Sciences, Shenyang, China
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Non-structural carbohydrates regulated by season and species in the subtropical monsoon broad-leaved evergreen forest of Yunnan Province, China. Sci Rep 2018; 8:1083. [PMID: 29348653 PMCID: PMC5773538 DOI: 10.1038/s41598-018-19271-8] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2017] [Accepted: 12/27/2017] [Indexed: 11/08/2022] Open
Abstract
Non-structural carbohydrates (NSC) play important roles in adapting to environments in plants. Despite extensive research on the seasonal dynamics and species differences of NSC, the relative contributions of season and species to NSC is not well understood. We measured the concentration of starch, soluble sugar, NSC, and the soluble sugar:starch ratio in leaves, twigs, trunks and roots of twenty dominant species for dry and wet season in monsoon broad-leaved evergreen forest, respectively. The majority of concentration of NSC and starch in the roots, and the leaves contained the highest concentration of soluble sugar. A seasonal variation in starch and NSC concentrations higher in the dry season. Conversely, the wet season samples had higher concentration of soluble sugar and the sugar:starch ratio. Significant differences exist for starch, soluble sugar and NSC concentrations and the sugar:starch ratio across species. Most species had higher starch and NSC concentrations in the dry season and higher soluble sugar concentration and the sugar:starch ratio in wet season. Repeated variance analysis showed that starch and NSC concentrations were strongly affected by season although the effect of seasons, species, and the interaction of the two on the starch, soluble sugar, and NSC concentrations were significant.
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O'Grady AP, Mitchell PJ. Looking forward, looking back: capturing drought in flagrante delicto and uncovering its broader consequences for forest ecosystems. TREE PHYSIOLOGY 2015; 35:803-805. [PMID: 26311305 DOI: 10.1093/treephys/tpv072] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Affiliation(s)
- A P O'Grady
- CSIRO Land and Water Flagship, Private Bag 12, Hobart, Tasmania 7001, Australia
| | - P J Mitchell
- CSIRO Land and Water Flagship, Private Bag 12, Hobart, Tasmania 7001, Australia
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Reinhardt K, Germino MJ, Kueppers LM, Domec JC, Mitton J. Linking carbon and water relations to drought-induced mortality in Pinus flexilis seedlings. TREE PHYSIOLOGY 2015; 35:771-82. [PMID: 26116925 DOI: 10.1093/treephys/tpv045] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/24/2014] [Accepted: 04/24/2015] [Indexed: 05/24/2023]
Abstract
Survival of tree seedlings at high elevations has been shown to be limited by thermal constraints on carbon balance, but it is unknown if carbon relations also limit seedling survival at lower elevations, where water relations may be more important. We measured and modeled carbon fluxes and water relations in first-year Pinus flexilis seedlings in garden plots just beyond the warm edge of their natural range, and compared these with dry-mass gain and survival across two summers. We hypothesized that mortality in these seedlings would be associated with declines in water relations, more so than with carbon-balance limitations. Rather than gradual declines in survivorship across growing seasons, we observed sharp, large-scale mortality episodes that occurred once volumetric soil-moisture content dropped below 10%. By this point, seedling water potentials had decreased below -5 MPa, seedling hydraulic conductivity had decreased by 90% and seedling hydraulic resistance had increased by >900%. Additionally, non-structural carbohydrates accumulated in aboveground tissues at the end of both summers, suggesting impairments in phloem-transport from needles to roots. This resulted in low carbohydrate concentrations in roots, which likely impaired root growth and water uptake at the time of critically low soil moisture. While photosynthesis and respiration on a leaf area basis remained high until critical hydraulic thresholds were exceeded, modeled seedling gross primary productivity declined steadily throughout the summers. At the time of mortality, modeled productivity was insufficient to support seedling biomass-gain rates, metabolism and secondary costs. Thus the large-scale mortality events that we observed near the end of each summer were most directly linked with acute, episodic declines in plant hydraulic function that were linked with important changes in whole-seedling carbon relations.
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Affiliation(s)
- Keith Reinhardt
- Department of Biological Sciences, Idaho State University, Pocatello, ID 83209-8007, USA
| | - Matthew J Germino
- United States Geological Survey, Forest and Rangeland Ecosystem Science Center, Boise, ID 83706, USA
| | - Lara M Kueppers
- Sierra Nevada Research Institute, University of California, Merced, CA 95343, USA
| | - Jean-Christophe Domec
- Bordeaux Sciences Agro, INRA ISPA UMR 1391, 33175 Gradignan, France Nicholas School of the Environment, Duke University, Durham, NC 27708, USA
| | - Jeffry Mitton
- Department of Ecology and Evolutionary Biology, University of Colorado-Boulder, Boulder, CO 80309, USA
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Mitchell PJ, O'Grady AP, Tissue DT, Worledge D, Pinkard EA. Co-ordination of growth, gas exchange and hydraulics define the carbon safety margin in tree species with contrasting drought strategies. TREE PHYSIOLOGY 2014; 34:443-58. [PMID: 24664613 DOI: 10.1093/treephys/tpu014] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/03/2023]
Abstract
Gas exchange, growth, water transport and carbon (C) metabolism diminish during drought according to their respective sensitivities to declining water status. The timing of this sequence of declining physiological functions may determine how water and C relations compromise plant survival. In this paper, we test the hypothesis that the degree of asynchrony between declining C supply (photosynthesis) and C demand (growth and respiration) determines the rate and magnitude of changes in whole-plant non-structural carbohydrates (NSC) during drought. Two complementary experiments using two tree species (Eucalyptus globulus Labill. and Pinus radiata D. Don) with contrasting drought response strategies were performed to (i) assess changes in radial stem growth, transpiration, leaf water potential and gas exchange in response to chronic drought, and (ii) evaluate the concomitant impacts of these drought responses on the temporal patterns of NSC during terminal drought. The three distinct phases of water stress were delineated by thresholds of growth cessation and stomatal closure that defined the 'carbon safety margin' (i.e., the difference between leaf water potential when growth is zero and leaf water potential when net photosynthesis is zero). A wider C safety margin in E. globulus was defined by an earlier cessation of growth relative to photosynthesis that reduced the demand for NSC while maintaining C acquisition. By contrast, the narrower C safety margin in P. radiata was characterized by a synchronous decline in growth and photosynthesis, whereby growth continued under a declining supply of NSC from photosynthesis. The narrower C safety margin in P. radiata was associated with declines in starch concentrations after ∼ 90 days of chronic drought and significant depletion of starch in all organs at mortality. The observed divergence in the sensitivity of drought responses is indicative of a potential trade-off between maintaining hydraulic safety and adequate C availability.
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Affiliation(s)
- P J Mitchell
- CSIRO Ecosystem Sciences, Climate Adaptation Flagship, Private Bag 12, Hobart, TAS 7001, Australia
| | - A P O'Grady
- CSIRO Ecosystem Sciences, Climate Adaptation Flagship, Private Bag 12, Hobart, TAS 7001, Australia
| | - D T Tissue
- Hawkesbury Institute for the Environment, University of Western Sydney, Bourke Street, Richmond, NSW 2753, Australia
| | - D Worledge
- CSIRO Ecosystem Sciences, Climate Adaptation Flagship, Private Bag 12, Hobart, TAS 7001, Australia
| | - E A Pinkard
- CSIRO Ecosystem Sciences, Climate Adaptation Flagship, Private Bag 12, Hobart, TAS 7001, Australia
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Klein T, Yakir D, Buchmann N, Grünzweig JM. Towards an advanced assessment of the hydrological vulnerability of forests to climate change-induced drought. THE NEW PHYTOLOGIST 2014; 201:712-716. [PMID: 24117758 DOI: 10.1111/nph.12548] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/04/2023]
Affiliation(s)
- Tamir Klein
- Department of Environmental Sciences and Energy Research, Weizmann Institute of Science, Rehovot, Israel
- Institute of Botany, University of Basel, Basel, Switzerland
| | - Dan Yakir
- Department of Environmental Sciences and Energy Research, Weizmann Institute of Science, Rehovot, Israel
| | - Nina Buchmann
- Institute of Agricultural Sciences, ETH Zürich, Zürich, Switzerland
| | - José M Grünzweig
- Robert H. Smith Faculty of Agriculture, Food and Environment, the Hebrew University of Jerusalem, Rehovot, Israel
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Galvez DA, Landhäusser SM, Tyree MT. Root carbon reserve dynamics in aspen seedlings: does simulated drought induce reserve limitation? TREE PHYSIOLOGY 2011; 31:250-7. [PMID: 21444372 DOI: 10.1093/treephys/tpr012] [Citation(s) in RCA: 41] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/17/2023]
Abstract
In a greenhouse study we quantified the gradual change of gas exchange, water relations and root reserves of aspen (Populus tremuloides Michx.) seedlings growing over a 3-month period of severe water stress. The aim of the study was to quantify the complex interrelationship between growth, water and gas exchange, and root carbon (C) dynamics. Various growth, gas exchange and water relations variables in combination with root reserves were measured periodically on seedlings that had been exposed to a continuous drought treatment over a 12-week period and compared with well-watered seedlings. Although gas exchange and water relations parameters significantly decreased over the drought period in aspen seedlings, root reserves did not mirror this trend. During the course of the experiment roots of aspen seedlings growing under severe water stress showed a two orders of magnitude increase in sugar and starch content, and roots of these seedlings contained more starch relative to sugar than those in non-droughted seedlings. Drought resulted in a switch from growth to root reserves storage which indicates a close interrelationship between growth and physiological variables and the accumulation of root carbohydrate reserves. Although a severe 3-month drought period created physiological symptoms of C limitation, there was no indication of a depletion of root C reserve in aspen seedlings.
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Affiliation(s)
- David A Galvez
- Department of Renewable Resources, Faculty of Agricultural, Life and Environmental Sciences, University of Alberta, Edmonton, AB, Canada.
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Sala A, Piper F, Hoch G. Physiological mechanisms of drought-induced tree mortality are far from being resolved. THE NEW PHYTOLOGIST 2010; 186:274-81. [PMID: 20409184 DOI: 10.1111/j.1469-8137.2009.03167.x] [Citation(s) in RCA: 288] [Impact Index Per Article: 20.6] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/17/2023]
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Boulant N, Kunstler G, Rambal S, Lepart J. Seed supply, drought, and grazing determine spatio-temporal patterns of recruitment for native and introduced invasive pines in grasslands. DIVERS DISTRIB 2008. [DOI: 10.1111/j.1472-4642.2008.00494.x] [Citation(s) in RCA: 43] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022] Open
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