Photochemical efficiency correlated with candidate gene expression promote coffee drought tolerance

AbstractThe aim of this study was to identify the correlation between photochemical efficiency and candidate genes expression to elucidate the drought tolerance mechanisms in coffee progenies (Icatu Vermelho IAC 3851-2 × Catimor UFV 1602-215) previously identified as tolerant in field conditions. Four progenies (2, 5, 12 and 15) were evaluated under water-deficit conditions (water deficit imposed 8 months after transplanting seedlings to the pots) and under irrigated system. Evaluations of physiological parameters and expression of candidate genes for drought tolerance were performed. Progeny 5 showed capacity to maintain water potential, which contributed to lower qP variation between irrigated and deficit conditions. However, the increases of qN and NPQ in response to stress indicate that this progeny is photochemically responsive to small variations of Ψam protecting the photosystem and maintaining qP. Data obtained for progeny 12 indicated a lower water status maintenance capacity, but with increased qN and NPQ providing maintenance of the ɸPSII and ETR parameters. A PCA analysis revealed that the genes coding regulatory proteins, ABA-synthesis, cellular protectors, isoforms of ascorbate peroxidase clearly displayed a major response to drought stress and discriminated the progenies 5 and 12 which showed a better photochemical response. The genes CaMYB1, CaERF017, CaEDR2, CaNCED, CaAPX1, CaAPX5, CaGolS3, CaDHN1 and CaPYL8a were up-regulated in the arabica coffee progenies with greater photochemical efficiency under deficit and therefore contributing to efficiency of the photosynthesis in drought tolerant progenies.

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Physiological Responses under Drought Stress of Improved Drought-Tolerant Rice Lines and their Parents

Notulae Botanicae Horti Agrobotanici Cluj-Napoca ◽

10.15835/nbha46211188 ◽

2018 ◽

Vol 46 (2) ◽

pp. 679-687 ◽

Cited By ~ 6

Author(s):

Preeyanuch LARKUNTHOD ◽

Noppawan NOUNJAN ◽

Jonaliza L SIANGLIW ◽

Theerayut TOOJINDA ◽

Jirawat SANITCHON ◽

...

Keyword(s):

Drought Stress ◽

Drought Tolerance ◽

Water Status ◽

Physiological Responses ◽

High Water ◽

Recurrent Parent ◽

Potential Candidate ◽

Substitution Lines ◽

Chromosome Segment Substitution Lines ◽

Drought Tolerant

Many of the economically important rice cultivars including ‘Khao Dawk Mali 105’ (KDML105) or jasmine rice, one of the world’s famous rice exported from Thailand suffers from drought due to erratic rainfalls and limited irrigation. To improve drought tolerance and reserve genetic background of KDML105, chromosome segment substitution lines (CSSL) containing drought tolerant quantitative trait loci (DT-QTL) has been previously developed by backcrossing between KDML105 and drought tolerant donor, IR58586-F2-CA-143 (DH212). To understand the physiological responses related to drought tolerance in CSSL lines compared to parents, two CSSLs namely CSSL1-16 and CSSL1-18, respectively were used in this study. Twenty-one-d-old hydroponically grown plants were subjected to 20% PEG for 0, 7, 14 d and then recovered from stress for 3 d. The results indicated that CSSL lines especially, CSSL1-16 showed better performance under drought stress compared to their recurrent parent. Drought tolerance superior CSSL1-16 line was indicated by high water status (high relative water content and leaf water potential), good osmotic adjustment, high proline and greater membrane stability. Moreover, this line was able to resume growth after stress recovery whereas other lines/cultivar could not recover. Similarly, drought tolerant donor showed high water status suggesting that well-maintained plant water status was associated with drought tolerant trait. It could be concluded that the highest drought tolerant line was CSSL1-16 followed by DH212, CSSL1-18 and KDML105. It would be interesting to go further into introgressed section in CSSL1-16 to identify potential candidate genes in DT-QTL for breeding drought tolerant rice in the future.

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RESPOSTAS FISIOLÓGICAS E BIOQUÍMICAS DE PLANTAS DE AROEIRA (Myracrodruon urundeuva Allemão) AO DÉFICIT HÍDRICO E POSTERIOR RECUPERAÇÃO

Irriga ◽

10.15809/irriga.2015v20n4p705 ◽

2015 ◽

Vol 20 (4) ◽

pp. 705-717 ◽

Cited By ~ 6

Author(s):

Amanda Silva Costa ◽

Antonio Lucineudo Oliveira Freire ◽

Ivonete Alves Bakke ◽

Francisco Hevilásio Freire Pereira

Keyword(s):

Water Stress ◽

Stomatal Conductance ◽

Drought Tolerance ◽

Water Deficit ◽

Water Status ◽

Irrigation Treatment ◽

Photosynthesis Rate ◽

Organic Solutes ◽

Plastic Bags ◽

Black Plastic

RESPOSTAS FISIOLÓGICAS E BIOQUÍMICAS DE PLANTAS DE AROEIRA (Myracrodruon urundeuva Allemão) AO DÉFICIT HÍDRICO E POSTERIOR RECUPERAÇÃO AMANDA SILVA COSTA1; ANTONIO LUCINEUDO DE OLIVEIRA FREIRE2; IVONETE ALVES BAKKE3 E FRANCISCO HEVILÁSIO FREIRE PEREIRA4 1Engenheira Florestal - Mestre em Ciências Florestais pelo Programa de Pós-Graduação em Ciências Florestais – Unidade Acadêmica de Engenharia Florestal - Universidade Federal de Campina Grande/UFCG, Patos, PB, Brasil, [email protected] Agrônomo – Doutor - Unidade Acadêmica de Engenharia Florestal - Universidade Federal de Campina Grande/UFCG, Patos, PB, Brasil, [email protected] Florestal – Doutora - Unidade Acadêmica de Engenharia Florestal - Universidade Federal de Campina Grande/UFCG, Patos, PB, Brasil, [email protected] Agrônomo – Doutor - Unidade Acadêmica de Ciências Agrárias - Universidade Federal de Campina Grande/UFCG, Pombal, PB, Brasil, [email protected] 1 RESUMO A aroeira (Myracrodruon urundeuva Allemão) vem sendo explorada de forma desordenada, ocasionando redução drástica no número de indivíduos, fazendo com que passasse a fazer parte da lista de espécies ameaçadas de extinção, sendo oportuna a prioridade da conservação. No entanto, pouco se sabe a respeito de aspectos relacionados à sua fisiologia, principalmente acerca dos mecanismos fisiológicos que determinam sua tolerância à seca. O objetivo deste trabalho foi avaliar as trocas gasosas e o acúmulo de solutos orgânicos em plantas jovens de aroeira submetidas ao déficit hídrico e posterior recuperação. Plantas com doze meses de idade, mantidas em sacos plásticos pretos, contendo 5 kg de uma mistura de solo e esterco bovino (2:1) foram submetidas aos tratamentos irrigados (controle) e de déficit hídrico, o qual foi imposto através da suspensão da irrigação. Decorridos 12 dias de déficit hídrico, as plantas foram reidratadas. As plantas sob déficit hídrico apresentaram teor relativo de água de 70% ao final do período de estresse. O déficit hídrico promoveu redução progressiva na condutância estomática, na transpiração, na fotossíntese líquida e na eficiência no uso da água das plantas. A concentração intercelular de CO2 e as concentrações foliares de açúcares totais e aminoácidos solúveis totais aumentaram. Após a retomada da irrigação, ocorreu rápida recuperação no teor relativo de água, mas a recuperação da condutância estomática e da fotossíntese líquida ocorreu mais lentamente. As plantas de aroeira foram capazes de recuperar o status hídrico e o funcionamento do mecanismo estomático e fotossintético após a recuperação, demonstrando tolerância ao déficit hídrico. Palavras-chave: Fotossíntese, solutos orgânicos, trocas gasosas, tolerância à seca. COSTA, A, S.; FREIRE, A. L. O.; BAKKE, I. A.; PEREIRA, F. H. R.PHYSIOLOGICAL AND BIOCHEMICAL RESONSES OF Myracrodruon urundeuva Allemão PLANTS TO WATER DEFICIT AND REHYDRATION 2 ABSTRACT Myracrodruon urundeuva Allemao plants have been explored in a disorderly way, which has caused a sharp reduction in the number of individuals, and put them on the list of endangered species. Therefore, their conservation became timely priority. However, little is known about aspects concerning their physiology, mainly those related to physiological mechanisms which determine their drought tolerance. The objective of this study was to evaluate the stomatal behavior and accumulation of organic solutes in young plants subjected to water stress and subsequent rehydration. Twelve month-old plants, kept in black plastic bags, with 5 kg of a mixture of soil and bovine manure (2:1) were subjected to irrigation treatment (control) and water deficit by irrigation withdrawal. After 12 day-water deficit, plants were rehydrated. Plants under water deficit showed relative water content of 70% at the end of the stress. Water stress caused progressive reduction in stomatal conductance, transpiration, photosynthesis rate and water use efficiency of plants. Intercellular concentration of CO2 and leaf concentrations of total sugar and soluble amino acids increased. After resumption of irrigation, rapid recovery of relative content of water was observed in the second day, but recovery of the stomatal conductance and photosynthesis rate was slower. Plants were able to recover the water status and functioning of the stomatal and photosynthetic mechanisms after rehydration, which shows their tolerance to water stress. Keywords: Photosynthesis, organic solutes, gas exchanges, drought tolerance.

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Physiological and Proteomic Analysis Revealed the Response Mechanisms of two Different Grought-resistant Maize Varieties

10.21203/rs.3.rs-630007/v1 ◽

2021 ◽

Author(s):

Hongjie Li ◽

Mei Yang ◽

Chengfeng Zhao ◽

Yifan Wang ◽

Renhe Zhang

Keyword(s):

Drought Stress ◽

Drought Tolerance ◽

Stress Responses ◽

Molecular Chaperones ◽

Electron Flow ◽

Photochemical Efficiency ◽

Growth And Yield ◽

Protective Mechanism ◽

Drought Tolerant ◽

Maize Varieties

Abstract Background: Drought stress seriously limits the seedling growth and yield of maize. Despite previous studies on drought resistance mechanisms by which maize cope with water deficient, the link between physiological and molecular variations are largely unknown. To reveal the complex regulatory mechanisms, comparative physiology and proteomic analyses were conducted to investigate the stress responses of two maize cultivars with contrasting tolerance to drought stress. Results: Physiological results showed that SD609 (drought-tolerant) maintains higher photochemical efficiency by enhancing CEF (cyclic electron flow) protective mechanism and antioxidative enzymes activities. Proteomics analysis revealed a total of 198 and 102 proteins were differentially expressed in SD609 and SD902, respectively. Further enrichment analysis indicated that drought-tolerant ‘SD609’ increased the expression of proteins related to photosynthesis, antioxidants/detoxifying enzymes, molecular chaperones and metabolic enzymes. The up-regulation proteins related to PSII repair and photoprotection mechanisms resulted in more efficient photochemical capacity in tolerant variety under moderate drought. However, the drought-sensitive ‘SD902’ only induced molecular chaperones and sucrose synthesis pathways, and failed to protect the impaired photosystem. Further analysis indicated that proteins related to the electron transport chain, redox homeostasis and heat shock proteins (HSPs) could be important in protecting plants from drought stress. Conclusions: Our experiments explored the mechanism of drought tolerance, and obtained detailed information about the interconnection of physiological research and protein research. In summary, our findings could provide new clues into further understanding of drought tolerance mechanisms in maize.

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Evaluation of the economic effectiveness in pepper production in drought conditions

Trakia Journal of Sciences ◽

10.15547/tjs.2021.01.002 ◽

2021 ◽

Vol 19 (1) ◽

pp. 7-12

Author(s):

B. Arnaoudov ◽

H. Boteva ◽

Y. Arnaoudova Y. Arnaoudova

Keyword(s):

Drought Tolerance ◽

Capsicum Annuum ◽

Water Deficit ◽

Economic Effect ◽

Economic Assessment ◽

Rate Of Return ◽

Irrigation Regime ◽

Greenhouse Production ◽

Drought Tolerant ◽

Drought Conditions

The aim of the study is to select pepper genotypes with increased drought tolerance based on an economic assessment of productivity in conditions of water deficit. The experiments were conducted during 2018-2019 in glasshouse Venlo type in the MVCRI. Two variants of irrigation regime are applied: 100% irrigation norm and 50% irrigation norm according to the technology adopted for this production in eight pepper (Capsicum annuum L.) genotypes - lines № 1966, 1917, 1931, 1936, 1928, 1930, C41 and C45, which were cultivated as a substrate culture (PE bag 16 L) without heating. In assessing the economic indicators in greenhouse production of pepper in order to select drought-tolerant genotypes of pepper according to the summary indicator rate of return with the highest economic effect of drought achieved with reduced to 50% irrigation regime are distinguished lines № 1928, № 1966 and № 1931.

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Effect of Water Deficit on Morphoagronomic and Physiological Traits of Common Bean Genotypes with Contrasting Drought Tolerance

Water ◽

10.3390/w12010217 ◽

2020 ◽

Vol 12 (1) ◽

pp. 217

Author(s):

Leonardo Godoy Androcioli ◽

Douglas Mariani Zeffa ◽

Daniel Soares Alves ◽

Juarez Pires Tomaz ◽

Vânia Moda-Cirino

Keyword(s):

Drought Tolerance ◽

Common Bean ◽

Water Deficit ◽

Net Photosynthesis ◽

Physiological Traits ◽

Limiting Factors ◽

Direct Result ◽

Drought Tolerant ◽

Intrinsic Water Use Efficiency ◽

Influence Of Water

Water deficit is considered one of the most limiting factors of the common bean. Understanding the adaptation mechanisms of the crop to this stress is fundamental for the development of drought-tolerant cultivars. In this sense, the objective of this study was to analyze the influence of water deficit on physiological and morphoagronomic traits of common bean genotypes with contrasting drought tolerance, aiming to identify mechanisms associated with tolerance to water deficit. The experiment was carried out in a greenhouse, arranged in a randomized complete block 4 × 2 factorial design, consisting of four common bean genotypes under two water regimes (with and without water stress), with six replications. The morphoagronomic and physiological traits of four cultivars, two drought-tolerant (IAPAR 81 and BAT 477) and two drought-sensitive (IAC Tybatã and BRS Pontal), were measured for 0, 4, 8, and 12 days, under water deficit, initiated in the phenological stage R5. Water-deficit induced physiological changes in the plants, altering the evaluated morphoagronomic traits. The drought tolerance of cultivar BAT 477 is not only a direct result of the low influence of water deficit on its yield components, but also a consequence of the participation of multiple adaptive physiological mechanisms, such as higher intrinsic water use efficiency, net photosynthesis rate, transpiration, carboxylation efficiency, stomatal conductance, and intracellular concentration of CO2 under water deficit conditions. On the other hand, cultivar IAPAR 81 can be considered drought-tolerant for short water-deficit periods only, since after the eighth day of water deficit, the physiological activities decline drastically.

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Identification of Main-Effect and Environmental Interaction QTL and Their Candidate Genes for Drought Tolerance in a Wheat RIL Population Between Two Elite Spring Cultivars

Frontiers in Genetics ◽

10.3389/fgene.2021.656037 ◽

2021 ◽

Vol 12 ◽

Author(s):

S. M. Hisam Al Rabbi ◽

Ajay Kumar ◽

Sepehr Mohajeri Naraghi ◽

Suraj Sapkota ◽

Mohammed S. Alamri ◽

...

Keyword(s):

Drought Tolerance ◽

Candidate Genes ◽

Phenotypic Variation ◽

Kernel Weight ◽

Snp Markers ◽

Expression Variability ◽

Volume Weight ◽

Drought Tolerant ◽

Ril Population ◽

Major Qtl

Understanding the genetics of drought tolerance can expedite the development of drought-tolerant cultivars in wheat. In this study, we dissected the genetics of drought tolerance in spring wheat using a recombinant inbred line (RIL) population derived from a cross between a drought-tolerant cultivar, ‘Reeder’ (PI613586), and a high-yielding but drought-susceptible cultivar, ‘Albany.’ The RIL population was evaluated for grain yield (YLD), grain volume weight (GVW), thousand kernel weight (TKW), plant height (PH), and days to heading (DH) at nine different environments. The Infinium 90 k-based high-density genetic map was generated using 10,657 polymorphic SNP markers representing 2,057 unique loci. Quantitative trait loci (QTL) analysis detected a total of 11 consistent QTL for drought tolerance-related traits. Of these, six QTL were exclusively identified in drought-prone environments, and five were constitutive QTL (identified under both drought and normal conditions). One major QTL on chromosome 7B was identified exclusively under drought environments and explained 13.6% of the phenotypic variation (PV) for YLD. Two other major QTL were detected, one each on chromosomes 7B and 2B under drought-prone environments, and explained 14.86 and 13.94% of phenotypic variation for GVW and YLD, respectively. One novel QTL for drought tolerance was identified on chromosome 2D. In silico expression analysis of candidate genes underlaying the exclusive QTLs associated with drought stress identified the enrichment of ribosomal and chloroplast photosynthesis-associated proteins showing the most expression variability, thus possibly contributing to stress response by modulating the glycosyltransferase (TraesCS6A01G116400) and hexosyltransferase (TraesCS7B01G013300) unique genes present in QTL 21 and 24, respectively. While both parents contributed favorable alleles to these QTL, unexpectedly, the high-yielding and less drought-tolerant parent contributed desirable alleles for drought tolerance at four out of six loci. Regardless of the origin, all QTL with significant drought tolerance could assist significantly in the development of drought-tolerant wheat cultivars, using genomics-assisted breeding approaches.

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Proteins Involved in Energy Metabolism and Oxidative Regulation Associated with Genotypic Variations in Drought Tolerance for Tall Fescue

Journal of the American Society for Horticultural Science ◽

10.21273/jashs04385-18 ◽

2018 ◽

Vol 143 (3) ◽

pp. 207-212

Author(s):

Jianming Sun ◽

Yiming Liu ◽

Xianglin Li ◽

Bingru Huang

Keyword(s):

Drought Stress ◽

Drought Tolerance ◽

Tall Fescue ◽

Photochemical Efficiency ◽

Grass Species ◽

Drought Treatment ◽

Drought Tolerant ◽

Oxidative Regulation ◽

Tolerant Genotype ◽

Adaptation To Drought

Protein metabolism plays an important role in plant adaptation to drought stress. The objective of this study was to identify drought-responsive proteins associated with differential drought tolerance for a tolerant genotype (RU9) and a sensitive genotype (RU18) of tall fescue (Lolium arundinacea). Plants of both genotypes were grown under well-watered conditions or subjected to drought stress by withholding irrigation for 12 days in a growth chamber controlled at the optimal growth temperatures of 23/18 °C (day/night). Physiological analysis demonstrated that RU9 was relatively more drought tolerant than RU18, as shown by the higher leaf net photosynthetic rate (Pn) and photochemical efficiency at 12 days of drought treatment. Differentially expressed proteins between RU9 and RU18 exposed to drought stress were identified by two-dimensional electrophoresis and mass spectrometry (MS). Several proteins [photosystem I reaction center subunit II, Rubisco small subunit, and Glyceraldehyde-3-phosphate dehydrogenase (GADPH)] in photosynthesis, respiration, or oxidative regulation exhibited higher abundance in RU9 than RU18 under drought stress. These results suggested the critical importance of energy and oxidative metabolism in tall fescue adaptation to drought stress. Those abundant proteins in the drought-tolerant genotype could be used as biomarkers or developed to molecular markers to develop elite drought-tolerant germplasm in tall fescue and other cool-season perennial grass species.

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DT2008: A Promising New Genetic Resource for Improved Drought Tolerance in Soybean When Solely Dependent on Symbiotic N2Fixation

BioMed Research International ◽

10.1155/2015/687213 ◽

2015 ◽

Vol 2015 ◽

pp. 1-7 ◽

Cited By ~ 19

Author(s):

Saad Sulieman ◽

Chien Van Ha ◽

Maryam Nasr Esfahani ◽

Yasuko Watanabe ◽

Rie Nishiyama ◽

...

Keyword(s):

Drought Tolerance ◽

Water Deficit ◽

Growth And Development ◽

Genetic Resource ◽

Genetic Network ◽

Genomic Research ◽

Symbiotic Association ◽

Drought Tolerant ◽

Breeding Research ◽

Soybean Genotypes

Water deficit is one of the major constraints for soybean production in Vietnam. The soybean breeding research efforts conducted at the Agriculture Genetics Institute (AGI) of Vietnam resulted in the development of promising soybean genotypes, suitable for the drought-stressed areas in Vietnam and other countries. Such a variety, namely, DT2008, was recommended by AGI and widely used throughout the country. The aim of this work was to assess the growth of shoots, roots, and nodules of DT2008 versus Williams 82 (W82) in response to drought and subsequent rehydration in symbiotic association as a means to provide genetic resources for genomic research. Better shoot, root, and nodule growth and development were observed in the cultivar DT2008 under sufficient, water deficit, and recovery conditions. Our results represent a good foundation for further comparison of DT2008 and W82 at molecular levels using high throughput omic technologies, which will provide huge amounts of data, enabling us to understand the genetic network involved in regulation of soybean responses to water deficit and increasing the chances of developing drought-tolerant cultivars.

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The role of soluble sugars during drought in tropical tree seedlings with contrasting tolerances

Journal of Plant Ecology ◽

10.1093/jpe/rtaa017 ◽

2020 ◽

Vol 13 (4) ◽

pp. 389-397 ◽

Cited By ~ 2

Author(s):

Michael J O’Brien ◽

Annabelle Valtat ◽

Samuel Abiven ◽

Mirjam S Studer ◽

Robert Ong ◽

...

Keyword(s):

Drought Tolerance ◽

Water Deficit ◽

Soluble Sugars ◽

Tropical Tree ◽

Pulse Labelling ◽

Stem Water Potential ◽

Sensitive Species ◽

Drought Tolerant ◽

Tolerant Species

Abstract Aims Non-structural carbohydrates (NSCs) are plant storage compounds used for metabolism, transport, osmoregulation and regrowth following the loss of plant tissue. Even in conditions suitable for optimal growth, plants continue to store NSCs. This storage may be due to passive accumulation from sink-inhibited growth or active reserves that come at the expense of growth. The former pathway implies that NSCs may be a by-product of sink limitation, while the latter suggests a functional role of NSCs for use during poor conditions. Methods Using 13C pulse labelling, we traced the source of soluble sugars in stem and root organs during drought and everwet conditions for seedlings of two tropical tree species that differ in drought tolerance to estimate the relative allocation of NSCs stored prior to drought versus NSCs assimilated during drought. We monitored growth, stomatal conductance, stem water potential and NSC storage to assess a broad carbon response to drought. Important Findings We found that the drought-sensitive species had reduced growth, conserved NSC concentrations in leaf, stem and root organs and had a larger proportion of soluble sugars in stem and root organs that originated from pre-drought storage relative to seedlings in control conditions. In contrast, the drought-tolerant species maintained growth and stem and root NSC concentrations but had reduced leaf NSCs concentrations with a larger proportion of stem and root soluble sugars originated from freshly assimilated photosynthates relative to control seedlings. These results suggest the drought-sensitive species passively accumulated NSCs during water deficit due to growth inhibition, while the drought-tolerant species actively responded to water deficit by allocating NSCs to stem and root organs. These strategies seem correlated with baseline maximum growth rates, which supports previous research suggesting a trade-off between growth and drought tolerance while providing new evidence for the importance of plasticity in NSC allocation during drought.

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Novel Miscanthus genotypes selected for different drought tolerance phenotypes show enhanced tolerance across combinations of salinity and drought treatments

Annals of Botany ◽

10.1093/aob/mcz009 ◽

2019 ◽

Vol 124 (4) ◽

pp. 653-674 ◽

Cited By ~ 6

Author(s):

Evangelia Stavridou ◽

Richard J Webster ◽

Paul R H Robson

Keyword(s):

Drought Tolerance ◽

Water Deficit ◽

Salinity Stress ◽

Treatment Effects ◽

Soluble Sugars ◽

Growth Strategy ◽

Biomass Composition ◽

Stay Green ◽

Drought Tolerant ◽

Moderate Salinity

Abstract Background and Aims Water deficit and salinity stresses are often experienced by plants concurrently; however, knowledge is limited about the effects of combined salinity and water deficit stress in plants, and especially in C4 bioenergy crops. Here we aim to understand how diverse drought tolerance traits may deliver tolerance to combinations of drought and salinity in C4 crops, and identify key traits that influence the productivity and biomass composition of novel Miscanthus genotypes under such conditions. Methods Novel genotypes used included M. sinensis and M. floridulus species, pre-screened for different drought responses, plus the commercial accession Miscanthus × giganteus (M×g.). Plants were grown under control treatments, single stress or combinations of water deficit and moderate salinity stress. Morphophysiological responses, including growth, yield, gas exchange and leaf water relations and contents of proline, soluble sugars, ash and lignin were tested for significant genotypic and treatment effects. Key Results The results indicated that plants subjected to combined stresses showed more severe responses compared with single stresses. All novel drought-tolerant genotypes and M×g. were tolerant to moderate salinity stress. Biomass production in M. sinensis genotypes was more resilient to co-occurring stresses than that in M×g. and M. floridulus, which, despite the yield penalty produced more biomass overall. A stay-green M. sinensis genotype adopted a conservative growth strategy with few significant treatment effects. Proline biosynthesis was species-specific and was triggered by salinity and co-occurring stress treatments, mainly in M. floridulus. The ash content was compartmentalized differently in leaves and stems in the novel genotypes, indicating different mechanisms of ion accumulation. Conclusions This study highlights the potential to select novel drought-tolerant Miscanthus genotypes that are resilient to combinations of stress and is expected to contribute to a deeper fundamental knowledge of different mechanistic responses identified for further exploitation in developing resilient Miscanthus crops.

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