Drought Stress Tolerance and Photosynthetic Activity of Alloplasmic Lines T. dicoccum x T. aestivum

Tetraploid species T. dicoccum Shuebl is a potential source of drought tolerance for cultivated wheat, including common wheat. This paper describes the genotyping of nine stable allolines isolated in the offspring from crossing of T. dicoccum x T. aestivum L. using 21 microsatellite (simple sequence repeats—SSR) markers and two cytoplasmic mitochondrial markers to orf256, rps19-p genes; evaluation of drought tolerance of allolines at different stages of ontogenesis (growth parameters, relative water content, quantum efficiency of Photosystem II, electron transport rate, energy dissipated in Photosystem II); and the study of drought tolerance regulator gene Dreb-1 with allele-specific PCR (AS-MARKER) and partial sequence analysis. Most allolines differ in genomic composition and T. dicoccum introgressions. Four allolines—D-b-05, D-d-05, D-d-05b, and D-41-05—revealed signs of drought tolerance of varying degrees. The more drought tolerant D-41-05 line was also characterized by Dreb-B1 allele introgression from T. dicoccum. A number of non-specific patterns and significant differences in allolines in regulation of physiological parameters in drought conditions is identified. Changes in photosynthetic activity in stress-drought are shown to reflect the level of drought tolerance of the forms studied. The contribution of different combinations of nuclear/cytoplasmic genome and alleles of Dreb-1 gene in allolines to the formation of stress tolerance and photosynthetic activity is discussed.

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Canopy Temperature and Chlorophyll Content are Effective Measures of Drought Stress Tolerance in Durum Wheat

Notulae Scientia Biologicae ◽

10.15835/nsb10410288 ◽

2018 ◽

Vol 10 (4) ◽

pp. 575-583 ◽

Cited By ~ 1

Author(s):

Fereshteh JOKAR ◽

Rahmatollah KARIMIZADEH ◽

Asad MASOUMIASL ◽

Reza AMIRI FAHLIANI

Keyword(s):

Drought Tolerance ◽

Durum Wheat ◽

Stress Tolerance ◽

Chlorophyll Content ◽

Geometric Mean ◽

Canopy Temperature ◽

Stress Conditions ◽

Tolerance Index ◽

Wheat Varieties ◽

Drought Tolerant

Durum wheat (Triticum durum L.) is used for the preparation of multiple food products, including pasta and bread. Its production is restricted due to diverse environmental stresses i.e. drought and heat stress. Here, comparative analysis of durum wheat varieties was done by studying canopy temperature depression (CTD) and chlorophyll content (CHL), yield and yield contributing traits to evaluate their performance under stress and low stress conditions. Twelve durum wheat genotypes were studied under stressful and low-stress conditions in Gachsaran region of Iran. CTD and CHL were measured at two stages, from the emergence of fifty percent of inflorescence (ZGS 54) to watery ripe stage (ZGS 71). According to stress tolerance index (STI), mean productivity (MP) and geometric mean productivity (GMP) indices, genotype G10 exhibited the most, while genotype G6, the least relative tolerance, respectively. Based on MP and GMP, genotype G10 was found to be drought tolerant, while genotype G2 displayed the lowest amount of MP and GMP. Therefore these genotypes are recommended to be used as genitors in artificial hybridization for improvement of drought tolerance in other cultivars. All indices had high correlation with grain yield under stress and non-stress condition, indicating more suitability of these indices for selection of resistant genotype. Results of the present study showed that among drought tolerance indices, harmonic mean (HM), GMP, CTD and modified STI index (K2STI) can be used as the most suitable indicators for screening drought tolerant cultivars.

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Evaluation of diverse cowpea [Vigna unguiculata (L.) Walp.] germplasm accessions for drought tolerance

Legume Research - An International Journal ◽

10.18805/lr-428 ◽

2019 ◽

Author(s):

K.D. Nkoana ◽

Abe Shegro Gerrano ◽

E.T. Gwata

Keyword(s):

Drought Stress ◽

Drought Tolerance ◽

Water Content ◽

Relative Water Content ◽

Evaluation Method ◽

Moisture Stress ◽

Proline Content ◽

Drought Tolerant ◽

Relative Water ◽

Germplasm Accessions

The genetic potential for drought tolerance in cowpea within the small holder sector has not been fully exploited in South Africa. Thus, a drought evaluation experiment was conducted at the ARC-VOP to evaluate 28 cowpea germplasm accessions including two controls viz. IT96D-602 (drought tolerant) and TVU7778 (susceptible to drought) in the drought screening house using plastic box evaluation method in January, 2017. Genotypes raised for three weeks were subjected to 5 weeks of water stress treatment to determine their physiological response through leaf wilting index, relative water content and proline content followed by re-watering to determine genotype (s) with ability to recover from drought stress. Analyses of variance showed highly significant differences in response to moisture stress among the cowpea accessions for the selected physiological traits except for leaf wilting index at week two of drought stress. Stem greenness and recovery appeared to be a reliable indicator of drought tolerant genotypes which was readily observed in Acc1257, Acc1168, Acc2355, IT96D-602 and Acc5352 which also correlated significantly and positively with relative water content and proline content. The genotypes responded differently to drought stress indicating that there is sufficient genetic variability that can be utilized further in breeding for drought stress within the cowpea species.

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Use of physiological parameters as fast tools to screen for drought tolerance in sugarcane

Brazilian Journal of Plant Physiology ◽

10.1590/s1677-04202007000300003 ◽

2007 ◽

Vol 19 (3) ◽

pp. 193-201 ◽

Cited By ~ 124

Author(s):

Marcelo de A. Silva ◽

John L. Jifon ◽

Jorge A.G. da Silva ◽

Vivek Sharma

Keyword(s):

Drought Stress ◽

Drought Tolerance ◽

Crop Improvement ◽

Relative Increase ◽

Physiological Parameters ◽

Screening Tools ◽

Leaf Chlorophyll ◽

Drought Tolerant ◽

Relative Water ◽

Leaf Relative Water Content

Drought is one of the major limitations to plant productivity worldwide. Identifying suitable screening tools and quantifiable traits would facilitate the crop improvement process for drought tolerance. In the present study, we evaluated the ability of four relatively physiological parameters (variable-to-maximum chlorophyll a fluorescence ratio, F v/F m; estimated leaf chlorophyll content via SPAD index; leaf temperature, LT; and, leaf relative water content, RWC) to distinguish between drought tolerant and susceptible sugarcane genotypes subjected to a 90-d drought cycle. Eight field-grown genotypes were studied. By 45 d after the onset of treatments, the F v/F m, SPAD index and RWC of drought-stressed plants had declined significantly in all genotypes compared to values at the onset of well-watered treatments. However, the reductions were more severe in leaves of susceptible genotypes. Under drought stress, the tolerant genotypes as a group, maintained higher F v/F m (8%), SPAD index (15%), and RWC (16%) than susceptible genotypes. In general, LT of drought-stressed plants was higher (~4ºC) than that of well-watered plants but the relative increase was greater among drought susceptible genotypes. Under drought stress, LT of tolerant genotypes was on average 2.2ºC lower than that of susceptible genotypes. The results are consistent with the tolerant-susceptible classification of these genotypes and indicate that these tools can be reliable in screening for drought tolerance, with F v/F m, SPAD index and LT having the added advantage of being nondestructive and easily and quickly assessed.

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Standardization of screening technique and evaluation of muskmelon genotypes for drought tolerance

Plant Genetic Resources ◽

10.1017/s1479262116000253 ◽

2016 ◽

Vol 16 (1) ◽

pp. 1-8 ◽

Cited By ~ 5

Author(s):

Sudhakar Pandey ◽

Waquar Akhter Ansari ◽

Neelam Atri ◽

Bijendra Singh ◽

Sunil Gupta ◽

...

Keyword(s):

Drought Tolerance ◽

Chlorophyll Concentration ◽

Screening Method ◽

Visual Observation ◽

Point Scale ◽

Yield Efficiency ◽

Commercial Cultivation ◽

Drought Tolerant ◽

Root And Shoot Length ◽

Relative Water

AbstractA five-point drought stress screening methodology for muskmelon based on visual observation has been standardized by modifying an earlier field screening method. The scale (1 to 5), were categorized into five groups, namely, highly drought tolerant (1), drought tolerant (2), average drought tolerant (3), drought susceptible (4) and highly drought susceptible (5). To validate and standardized the technique, 48 genotypes of muskmelon were evaluated for two successive years. Important physiological parameters, i.e.: relative water content (RWC), electrolyte leakage, photosynthetic efficiency (Fv/Fm), chlorophyll concentration index (CCI), root and shoot length were measured and correlated to make screening results more reliable. Drought tolerance efficiency of genotypes was calculated based on yield, and drought-tolerant genotypes were identified with better yield efficiency and ranking on visual scale. Whereas, yield efficiency of some drought-tolerant genotypes were less, althouth they came under drought-tolerant scale. Being a tolerant genotype, these may not be economical for commercial cultivation. Under water-deficit condition a significant positive correlation was observed between drought tolerance efficiency, and RWC, Fv/Fm, CCI and root length. Out of 48 genotypes, 14 genotypes were came under highly drought-tolerant category based on 5 point scale.

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Growth Performance and Antioxidant Enzyme Activities of Advanced Mutant Rice Genotypes under Drought Stress Condition

Agronomy ◽

10.3390/agronomy8120279 ◽

2018 ◽

Vol 8 (12) ◽

pp. 279 ◽

Cited By ~ 7

Author(s):

Zarifth Kamarudin ◽

Mohd Yusop ◽

Mahmud Tengku Muda Mohamed ◽

Mohd Ismail ◽

Abdul Harun

Keyword(s):

Drought Stress ◽

Drought Tolerance ◽

Enzyme Activities ◽

Stress Condition ◽

Growth Parameters ◽

Proline Content ◽

Antioxidant Enzyme Activities ◽

Drought Tolerant ◽

Drought Stress Condition ◽

Rice Genotypes

Drought stress affects various physiological and metabolic processes in rice (Oryza sativa L.) plant. Non-availability of high-yielding varieties suitable for cultivation under drought condition lead towards a sharp decline in rice yield. Induce mutation is an essential auxiliary approach to counterpart conventional breeding to produce stress-tolerance rice variety. The current study was aimed to identify two advanced mutant rice genotypes as drought-tolerant using growth parameters and antioxidant enzyme activities. The advanced mutant rice genotypes, MR219-4 and MR219-9, showed a minimal reduction on all growth parameters, yield, and yield components measured for drought tolerance. MR219-4 had a slight reduction on total dry weight and chlorophyll content under drought stress condition. Proline content increased significantly in drought-tolerant rice genotypes and the highest proline content was obtained from MR219-4 followed by MR219-9 under drought stress. Catalase, ascorbate peroxidase, and guaiacol peroxidase activities were significantly increased in drought stress treatment in all the rice genotypes. MR219-4 and MR219-9 were identified as high-yielding drought-tolerant genotypes as they maintained good performance under drought stress condition for all the measured traits compared to the drought-tolerant check varieties, Aeron1 and MR219, thus, this might be underlying selection criteria for a drought tolerance rice breeding programme.

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Enhanced Drought Tolerance of Arabica Coffee (Coffea arabica L.) by Grafting Method

Sains Malaysiana ◽

10.17576/jsm-2021-5011-06 ◽

2021 ◽

Vol 50 (11) ◽

pp. 3219-3229

Author(s):

Ngoc-Thang Vu ◽

Jong-Man Park ◽

Ngoc-Quat Nguyen ◽

Trong-Truong-Son Nguyen ◽

Il-Soep Kim ◽

...

Keyword(s):

Drought Tolerance ◽

Water Deficit ◽

Coffea Arabica ◽

Growth Parameters ◽

Dry Weight ◽

Leaf Length ◽

Ion Leakage ◽

Leaf Chlorophyll ◽

Relative Water ◽

Coffee Plants

The objective of this study was to evaluate grafting method to improve the drought tolerance of Coffea arabica. Using C. arabica species as scions, and C. robusta as rootstock, the grafted plant was compared with the non-grafted plant (C. arabica) under water deficit condition. The result shown that growth parameters such as plant height, leaf length, and leaf width of the grafted coffee plants were higher than those of the non-grafted. The leaf area, fresh and dry weight of plants were highly reduced in non-grafted coffee plants. The leaf chlorophyll content (SPAD) and chlorophyll fluorescence (Fv/Fm) values of the grafted and non-grafted coffee plants decreased significantly with increasing duration under water deficit condition. The SPAD and Fv/Fm values of the two coffee types were also increased significantly with increasing duration after re-watering. Compared to the non-grafted plants, higher values of SPAD, Fv/Fm and relative water content in the leaf were observed in the grafted coffee plants. Moreover, lower values of relative ion leakage were observed in the grafted coffee plants after three days of water withholding and one month after re-watering. On the other hand, the grafted coffee plants showed enhanced drought tolerance by reducing the percentages of wilting plant under water deficit condition, and increasing the recovery percentages after re-watering.

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Screening for drought tolerance in cultivars of the ornamental genusTagetes(Asteraceae)

PeerJ ◽

10.7717/peerj.2133 ◽

2016 ◽

Vol 4 ◽

pp. e2133 ◽

Cited By ~ 11

Author(s):

Raluca Cicevan ◽

Mohamad Al Hassan ◽

Adriana F. Sestras ◽

Jaime Prohens ◽

Oscar Vicente ◽

...

Keyword(s):

Oxidative Stress ◽

Drought Tolerance ◽

Plant Growth ◽

Growth Parameters ◽

Soluble Sugars ◽

Stem Length ◽

Total Phenolic ◽

Total Soluble Sugars ◽

Drought Tolerant ◽

Components Analysis

Drought tolerance was evaluated in twelve cultivars of three ornamentalTagetesspecies (T. patula,T. tenuifoliaandT. erecta). A stress treatment was performed by completely stopping watering of plants maintained in controlled greenhouse conditions. After three weeks, several plant growth parameters (stem length (SL), fresh weight (FW) and water content (WC)), photosynthetic pigments (chlorophylls and carotenoids (Car)), osmolytes (proline (Pro), glycine betaine (GB) and total soluble sugars (TSS)), an oxidative stress maker (malondialdehyde (MDA)) and antioxidants (total phenolic compounds (TPC) and total flavonoids (TF)) were measured. Considerable differences in the evaluated traits were found among the control and drought-stressed plants. Drought stress generally caused a marked reduction in plant growth and carotenoid pigments, and an increase in soluble solutes and oxidative stress. For most cultivars, proline levels in stressed plants increased between 30 and 70-fold compared to the corresponding controls. According to the different measured parameters, on averageT. erectaproved to be more tolerant to drought thanT. patulaandT. tenuifolia. However, a considerable variation in the tolerance to drought was found within each species. The traits with greater association to drought tolerance as well as the most tolerant cultivars could be clearly identified in a principal components analysis (PCA). Overall, our results indicate that drought tolerant cultivars ofTagetescan be identified at early stages using a combination of plant growth and biochemical markers.

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Transcriptome analysis of drought-tolerant sorghum genotype SC56 in response to water stress reveals an oxidative stress defense strategy

10.21203/rs.2.13124/v1 ◽

2019 ◽

Author(s):

Farida Olden ◽

Arthur G. Hunt ◽

Randy Dinkins

Keyword(s):

Oxidative Stress ◽

Water Stress ◽

Drought Tolerance ◽

Stress Tolerance ◽

Differential Expression ◽

Expression Analysis ◽

Transcriptome Analysis ◽

Differential Expression Analysis ◽

Drought Tolerant ◽

Drought Conditions

Abstract Background Drought tolerance is a crucial trait for crops to curtail the yield loss inflicted by water stress to crops, yet genetic improvement efforts are challenged by the complexity of this character. The adaptation of sorghum to abiotic stress, its genotypic variability, and relatively small genome make this species well-suited to dissect the molecular basis of drought tolerance. One efficient approach to this question is the use of differential transcriptome analysis, which provides a snapshot of the processes underlying drought response as well as genes that might be determinants of the drought tolerance trait. Results RNA sequencing was used to compare the transcriptome profiles of two sorghum lines, the drought-tolerant SC56 and the drought-sensitive Tx7000. The differential expression analysis revealed unambiguous genotypic disparities, including a massive increase of upregulated transcripts in SC56. Concomitantly, gene ontology enrichment showed that SC56 biologically outperformed Tx7000 in wet conditions, since it upregulated processes driving growth and guaranteeing homeostasis. The drought tolerance of SC56 seems to be an intrinsic trait that occurs through the overexpression of stress tolerance genes in wet conditions, notably those acting in defense against oxidative stress (SOD1, SOD2, VTC1, MDAR1, MSRB2, and ABC1K1). Under drought conditions, SC56 enhanced its transmembrane transport and maintained growth-promoting mechanisms similar to those implemented under wet conditions. SC56 also appears to preserve its biological function, in a limiting environment, by relying on reported validated stress tolerance genes that heighten the antioxidant capacity (SOD1, RCI3, VTE1, UCP1, FD1, and FD2), regulatory factors (CIPK1 and CRK7), and repressors of premature senescence (SAUL1). Of the stress tolerance genes overexpressed under both wet and drought conditions, DHAR2 might be a key determinant of drought tolerance since its role in recycling ascorbic acid was described to be directly linked to protection against reactive oxygen species-mediated damage, positive effects on photosynthetic activity, higher rate of plant growth, and delayed leaf aging. Conclusion The differential expression analysis uncovered biological processes which upregulation enables SC56 to be a better accumulator of biomass and connects the drought tolerance trait to key stress tolerance genes, making this genotype a judicious choice for isolation of tolerance genes.

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Evaluation of Drought Tolerance Indices for Screening Some of Corn (Zea mays L.) Cultivars under Environmental Conditions

Notulae Scientia Biologicae ◽

10.15835/nsb539049 ◽

2013 ◽

Vol 5 (3) ◽

pp. 388-393 ◽

Cited By ~ 20

Author(s):

Mohhamad Reza NAGHAVI ◽

Alireza POUR ABOUGHADAREH ◽

Marouf KHALILI

Keyword(s):

Zea Mays ◽

Drought Tolerance ◽

Stress Tolerance ◽

Zea Mays L ◽

Stress Conditions ◽

Tolerance Index ◽

Drought Tolerant ◽

Drought Tolerance Indices ◽

Stress Susceptibility ◽

Tolerance Indices

In order to study the effect of drought stress on eight cultivars corn (Zea mays L.), an experiment was conducted in a factorial experimental on the basis of randomized complete block design under two irrigated conditions during 2010-2011 cropping season. Twelve drought tolerance/resistance indices including stress tolerance index (STI), stress susceptibility index (SSI), tolerance index (TOL), geometric mean production (GMP), mean production (MP), yield index (YI), yield stability index (YSI), drought resistance index (DI), relative drought index (RDI), stress susceptibility percentage index (SSPI) and modified stress tolerance (K1STI and K2STI) were calculated based on grain yield under drought and irrigated conditions. Yield in stress and non-stress conditions were significantly and positively correlated with STI, GMP, MP, YI, TOL, DI, RDI, YSI, SSPI, K1STI, and K2STI and negatively correlated with SSI. Yield in stress and non-stress conditions were significantly and positively correlated with STI, GMP, MP, YI, TOL, DI, RDI, YSI, SSPI, K1STI, and K2STI and negatively correlated with SSI. Screening drought tolerant cultivars using ranking method, three dimensional plots discriminated cultivars ‘KSC720’, KSC 710GT and ‘KSC 700’ as the most drought tolerant. Cluster analysis classified the cultivars into three groups i.e., tolerant, susceptible and semi-susceptible to drought conditions. In general, Results of this study showed that among drought tolerance indices STI, YI, SSPI, K1STI, and K2STI can be used as the most suitable indicators for screening drought tolerant cultivars and ‘KSC720’, KSC 710 GT and ‘KSC 700’ had the highest tolerance to drought in our studies condition.

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Seed Antioxidants Interplay with Drought Stress Tolerance Indices in Chilli (Capsicum annuum L) Seedlings

BioMed Research International ◽

10.1155/2018/1605096 ◽

2018 ◽

Vol 2018 ◽

pp. 1-14 ◽

Cited By ~ 7

Author(s):

U. Lakshmi Sahitya ◽

M. S. R. Krishna ◽

R. Sri Deepthi ◽

G. Shiva Prasad ◽

D. Peda Kasim

Keyword(s):

Water Stress ◽

Drought Tolerance ◽

Water Content ◽

Stress Tolerance ◽

Chlorophyll Content ◽

Relative Water Content ◽

Field Capacity ◽

Water Regimes ◽

Relative Water ◽

Tolerance Indices

Altering climatic conditions and water stress drastically affects the chilli crop yield. In this scenario we adapted a strategic approach for screening of elite chilli genotypes, by exploring role of seed antioxidants in stress tolerance during vegetative phase. A total of 20 chilli genotypes’ seed antioxidant potential and its effect on water stress tolerance were studied at three water regimes, namely, control (100% Field Capacity), moderate (80% Field Capacity), and severe (60% Field Capacity) stress conditions. Drought tolerance traits relative water content, chlorophyll content, and activities of superoxide dismutase and catalase enzymes were measured. A strong correlation was observed between seed antioxidants and water stress tolerant traits in seedlings. Genotypes KCa-5, KCa-6, and KCa-10 showed low quantity of H2O2 and Malondialdehyde in seeds and maintained high membrane integrity and chlorophyll content in seedlings. High content of proline in KCa-5, KCa-7, and KCa-10 seeds retained high relative water content at seedling stage under severe water stress. Present work reveals genotypic differences of hot pepper to different water regimes. Based on Principal Component Analysis (PCA) of seed antioxidant variables and drought tolerance indices twenty genotypes segregated into three clusters, namely, drought tolerant and susceptible and moderately tolerant.

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