Evaluation of Drought Tolerance among a Number of Wild Diploid Populations, Tetraploid and Hexaploid Cultivars of Wheat Using Morphological and Agronomic Traits

The influence of 24-epibrassinolide (EBR24), applied to leaves at a concentration of 5 μM, on plant physio-biochemistry and its reflection on crop water productivity (CWP) and other agronomic traits of six maize hybrids was field-evaluated under semi-arid conditions. Two levels of irrigation water deficiency (IWD) (moderate and severe droughts; 6000 and 3000 m3 water ha−1, respectively) were applied versus a control (well-watering; 9000 m3 water ha−1). IWD reduced the relative water content, membrane stability index, photosynthetic efficiency, stomatal conductance, and rates of transpiration and net photosynthesis. Conversely, antioxidant enzyme activities and osmolyte contents were significantly increased as a result of the increased malondialdehyde content and electrolyte leakage compared to the control. These negative influences of IWD led to a reduction in CWP and grain yield-related traits. However, EBR24 detoxified the IWD stress effects and enhanced all the above-mentioned parameters. The evaluated hybrids varied in drought tolerance; Giza-168 was the best under moderate drought, while Fine-276 was the best under severe drought. Under IWD, certain physiological traits exhibited a highly positive association with yield and yield-contributing traits or CWP. Thus, exogenously using EBR24 for these hybrids could be an effective approach to improve plant and water productivity under reduced available water in semi-arid environments.

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miR2105 regulates ABA biosynthesis via OsbZIP86-OsNCED3 module to contribute to drought tolerance in rice

10.1101/2021.09.21.461241 ◽

2021 ◽

Author(s):

Weiwei Gao ◽

Mingkang Li ◽

Songguang Yang ◽

Chunzhi Gao ◽

Yan Su ◽

...

Keyword(s):

Drought Stress ◽

Drought Tolerance ◽

Transgenic Rice ◽

Crucial Role ◽

Agronomic Traits ◽

Stomatal Closure ◽

Plant Tolerance ◽

Rice Plants ◽

Transgenic Rice Plants ◽

Aba Biosynthesis

AbstractInduced abscisic acid (ABA) biosynthesis plays an important role in plant tolerance to abiotic stresses, including drought, cold and salinity. However, regulation pathway of the ABA biosynthesis in response to stresses is unclear. Here, we identified a rice miRNA, osa-miR2105 (miR2105), which plays a crucial role in ABA biosynthesis under drought stress. Analysis of expression, transgenic rice and cleavage site showed that OsbZIP86 is a target gene of miR2105. Subcellular localization and luciferase activity assays showed that OsbZIP86 is a nuclear transcription factor. In vivo and in vitro analyses showed that OsbZIP86 directly binds to the promoter of OsNCED3, and interacts with OsSAPK10, resulting in enhanced-expression of OsNCED3. Transgenic rice plants with knock-down of miR2105 or overexpression of OsbZIP86 showed higher ABA content, more tolerance to drought, a lower rate of water loss, more stomatal closure than wild type rice ZH11 under drought stress. These rice plants showed no penalty with respect to agronomic traits under normal conditions. By contrast, transgenic rice plants with miR2105 overexpression, OsbZIP86 downregulation, or OsbZIP86 knockout displayed less tolerance to drought stress and other phenotypes. Collectively, our results show that a regulatory network of ‘miR2105-OsSAPK10/OsbZIP86-OsNCED3’ control ABA biosynthesis in response to drought stress.One-sentence summary‘miR2105-OsbZIP86-OsNCED3’ module plays crucial role in mediating ABA biosynthesis to contribute to drought tolerance with no penalty with respect to agronomic traits under normal conditions.

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Screening for Drought Tolerance in Thirty Three Taro Cultivars

Notulae Botanicae Horti Agrobotanici Cluj-Napoca ◽

10.15835/nbha46110950 ◽

2018 ◽

Vol 46 (1) ◽

pp. 65-74 ◽

Cited By ~ 8

Author(s):

José F.T. GANANÇA ◽

José G.R. FREITAS ◽

Humberto G.M. NÓBREGA ◽

Vanessa RODRIGUES ◽

Gonçalo ANTUNES ◽

...

Keyword(s):

Drought Tolerance ◽

Agronomic Traits ◽

Yield Stability ◽

Yield Potential ◽

High Yield ◽

Potential Yield ◽

Local Cultivars ◽

Drought Avoidance ◽

Drought Tolerant ◽

Long Duration

Taro [Colocasia esculenta (L.) Schott] is a root crop which is an important staple food in many regions of the world, producing 10.5 million tonnes on 1.4 million hectares a year. The crop is cultivated in wet (rain fed) or irrigated conditions, requiring on average 2,500 mm water per year, and in many countries it is cultivated in flooded plots. It is estimated that taro production could decrease by 40% as a result of the increase in drought and other severe events. In this work, thirty three accessions, including local cultivars, selected and hybrid lines were submitted to long duration drought stress and screened for tolerance. Twelve physiological, morphological and agronomic traits were measured at harvest, and subject to multivariate analysis. Stress indices, Water Use Efficiency and Factorial Analysis were useful for discriminating accessions regarding drought tolerance and yield stability, and drought tolerant and susceptible cultivars were identified. Our results confirm that different taro cultivars have different drought avoidance and tolerance strategies to cope with water scarcity. Better yield performers minimised biomass and canopy loss, while tolerance was observed in cultivars that presented low potential yield, but efficiently transferred resources to enhance corm formation. Among the 33 accessions, two local cultivars showed high yield stability and could be considered as suitable parents for breeding programs, while two others are well adapted to drought, but with overall low yield potential.

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Marker-trait association analysis for drought tolerance in smooth bromegrass

BMC Plant Biology ◽

10.1186/s12870-021-02891-0 ◽

2021 ◽

Vol 21 (1) ◽

Author(s):

F. Saeidnia ◽

M. M. Majidi ◽

A. Mirlohi

Keyword(s):

Drought Tolerance ◽

Association Analysis ◽

Deficit Irrigation ◽

Agronomic Traits ◽

Smooth Bromegrass ◽

Trait Association ◽

Irrigation Regimes ◽

Population Structure Analysis ◽

Drought Tolerance Indices ◽

Tolerance Indices

Abstract Background Little information is available on the application of marker-trait association (MTA) analysis for traits related to drought tolerance in smooth bromegrass. The objectives of this study were to identify marker loci associated with important agronomic traits and drought tolerance indices as well as fining stable associations in a diverse panel of polycross derived genotypes of smooth bromegrass. Phenotypic evaluations were performed at two irrigation regimes (normal and deficit irrigation) during 2 years; and association analysis was done with 626 SRAP markers. Results The results of population structure analysis identified three main subpopulations possessing significant genetic differences. Under normal irrigation, 68 and 57 marker-trait associations were identified using general linear model (GLM) and mixed linear mode1 (MLM), respectively. While under deficit irrigation, 61 and 54 markers were associated with the genes controlling the studied traits, based on these two models, respectively. Some of the markers were associated with more than one trait. It was revealed that markers Me1/Em5–11, Me1/Em3–15, and Me5/Em4–7 were consistently linked with drought-tolerance indices. Conclusion Following marker validation, the MTAs reported in this panel could be useful tools to initiate marker-assisted selection (MAS) and targeted trait introgression of smooth bromegrass under normal and deficit irrigation regimes, and possibly fine mapping and cloning of the underlying genes and QTLs.

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Participatory varietal selection among elite cowpea genotypes in northern Namibia

Legume Research - An International Journal ◽

10.18805/lr-334 ◽

2017 ◽

Author(s):

Lydia N. Horn ◽

Habteab M. Ghebrehiwot ◽

Fatma Sarsu ◽

Hussein A. Shimelis

Keyword(s):

Drought Tolerance ◽

Gamma Irradiation ◽

Vigna Unguiculata ◽

Agronomic Traits ◽

Plant Cover ◽

Participatory Varietal Selection ◽

Early Maturity ◽

Local Varieties ◽

Percent Percent ◽

Cowpea Varieties

The objective of this study was to select cowpea (Vigna unguiculata [L.] Walp.) varieties that meet farmers’ needs in Namibia, from a set of newly developed and elite cowpea varieties developed through gamma irradiation. Thirty four candidate mutant cowpea varieties derived from three local varieties, (Shindimba, Bira and Nakare), were evaluated for nine agronomic traits. The new genotypes descended from Bira were favourably selected by all participants for their best plant cover. The genotype L1P12 (Bi450) was preferred by 81 percent percent of farmers for its higher pod setting ability. The genotype R4P5 (Nk150) with longer pod size and R3P1 (Bi600) with early maturity were ideal candidates preferred by nearly all farmers. The present study has identified farmers’ most-preferred cowpea varieties selected for their best agronomic performances and drought tolerance. These selected cowpea genotype lines will further be subjected to distinct, uniformity and stability trials for varietal registration and release.

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Introgression of drought tolerance QTLs through marker assisted backcross breeding in wheat (Triticum aestivum L.)

Indian Journal of Genetics and Plant Breeding (The) ◽

10.31742/ijgpb.80.2.12 ◽

2020 ◽

Vol 80 (02) ◽

Author(s):

Leena Todkar ◽

Harikrishna . ◽

G. P. Singh ◽

Neelu Jain ◽

P. K. Singh ◽

...

Keyword(s):

Drought Tolerance ◽

Agronomic Traits ◽

Wheat Variety ◽

Triticum Aestivum L ◽

Recurrent Parent ◽

Background Selection ◽

Drought Tolerant ◽

Backcross Breeding ◽

Genomic Regions ◽

Marker Assisted Backcross Breeding

The present study reports the introgression of the genomic regions linked with drought tolerance traits viz., NDVI, staygreen, chlorophyll content/chlorophyll fluorescence and yield from a drought tolerant parent HI1500 in to a popular high yielding but drought susceptible wheat variety GW322 following the marker assisted backcross breeding. Background selection with 109 polymorphic SSR markers accelerated genome recovery of recurrent parent which ranged from 72.14 to 86.9% in BC1F1, 90.33 to 92.02% in BC2F1 and 91.6 to 94.95% with an average of 93.5% in BC2F2 generation. Eighteen homozygous BC2F3 progenies were found to be phenotypically superior for morpho-physiological and agronomic traits over the recurrent parent GW322.

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Agronomic and Physiological Evaluation of Wheat Cultivars under Deficit Irrigation Condition

International Journal of Agriculture and Biology ◽

10.17957/ijab/15.1748 ◽

2021 ◽

Vol 25 (05) ◽

pp. 929-936

Author(s):

Ruize Lin

Keyword(s):

Drought Tolerance ◽

Deficit Irrigation ◽

Agronomic Traits ◽

Soluble Sugar ◽

Growth Stages ◽

Antioxidant Enzyme Activities ◽

Drought Tolerant ◽

Osmolyte Accumulation ◽

Ros Homeostasis ◽

Late Growth

Improving crop productivity under drought conditions contributes largely to the sustainable agriculture globally. In this study, the agronomic traits and physiological processes related to osmolyte accumulation and reactive oxygen species (ROS) homeostasis during late growth stage in wheat under drought stress were studied. Three cultivars viz., Shimai 22 (drought tolerant), Zhongxinmai 99 (median drought-tolerant, control), and Shi 4185 (drought sensitive) sharing contrasting drought tolerance were grown under normal irrigation (NI: with irrigations prior to sowing, and at jointing and flowering stages) and deficit irrigation (DI, with irrigations prior to sowing and at jointing) conditions. Data regarding yields, osmolyte (i.e., proline and soluble sugar) contents, and antioxidant enzyme activities of superoxide dismutase (SOD), catalase (CAT), and peroxidase (POD), and malondialdehyde (MDA) contents were recorded. Under deficit irrigation, the cultivars displayed modified agronomic and physiological traits. Among cultivars, Shimai 22 showed best agronomic traits (6.47 to 7.23% higher yield than control), osmolyte contents and AE activities (10.12 to 22.18% higher than control), and least MDA accumulation (12.30 to 17.06% lower than control). In contrast, Shi 4185 cultivar performed worst regarding above said traits. The transcripts of the genes in ��1-Pyrroline-5-carboxylate synthetase (P5CS) family that regulates proline biosynthesis and those in AE families that modulate ROS homeostasis were evaluated. Results revealed that the P5CS genes TaP5CS2 and TaP5CS5 and the AE ones TaSOD3, TaCAT2 and TaCAT5 were modified on transcripts across the cultivars under DI condition, showing to be significant upregulated compared with NI. These results suggested the essential roles of osmolyte accumulation and AE proteins in improving the drought tolerance of wheat during late growth stages. In addition, this study suggested that the elevated transcription efficiencies of distinct P5CS and AE family genes under water deprivation contribute to the enhanced drought tolerance in drought-tolerant cultivars. © 2021 Friends Science Publishers

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Detection of drought tolerance-related QTL in the Plainsman V./Cappelle Desprez doubled haploid wheat population

Cereal Research Communications ◽

10.1007/s42976-021-00229-y ◽

2021 ◽

Author(s):

É. Nagy ◽

Á. Szabó-Hevér ◽

S. Lehoczki-Krsjak ◽

C. Lantos ◽

E. Kiss ◽

...

Keyword(s):

Drought Tolerance ◽

Grain Yield ◽

Doubled Haploid ◽

Agronomic Traits ◽

Abiotic Factors ◽

Phenotypic Variance ◽

Thousand Grain Weight ◽

Dh Population ◽

Wheat Population ◽

Irrigation Levels

AbstractDrought stress is one of the major abiotic factors that significantly reduces wheat grain yield. Improving drought tolerance is a challenge that plant breeders are facing nowadays. In this study, our goal was to identify quantitative trait loci (QTL) in the Plainsman V./Cappelle Desprez doubled haploid (DH) population under drought induced as decreased irrigation (ds) and well-watered (ww) conditions in glasshouse. In total, 54 QTL were detected across the three years in two water regimes linked to 10 drought tolerance-related agronomic traits. Out of the detected QTL regions several have been previously reported. The QTL on chromosome 1A (wPt-744613-wPt-8016) related to thousand grain weight was detected in both ds and ww conditions, explaining the 12.7–17.4% of the phenotypic variance. QTL for grain yield was detected on chromosomes 1A, and 6B in the ds treatment. Numerous QTL was identified under both irrigation levels.

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Evaluation of Agronomic Traits and Drought Tolerance of Winter Wheat Accessions from the USDA-ARS National Small Grains Collection

Agronomy ◽

10.3390/agronomy7030051 ◽

2017 ◽

Vol 7 (3) ◽

pp. 51 ◽

Cited By ~ 11

Author(s):

Yuxiu Liu ◽

Brian Bowman ◽

Yin-Gang Hu ◽

Xi Liang ◽

Weidong Zhao ◽

...

Keyword(s):

Drought Tolerance ◽

Winter Wheat ◽

Agronomic Traits ◽

Small Grains

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Marker-trait association analysis for drought tolerance in smooth bromegrass

10.21203/rs.3.rs-18211/v2 ◽

2020 ◽

Author(s):

Fatemeh Saeidnia ◽

Mohammad Mahdi Majidi ◽

Aghafakhr Mirlohi

Keyword(s):

Drought Tolerance ◽

Association Analysis ◽

Deficit Irrigation ◽

Agronomic Traits ◽

Smooth Bromegrass ◽

Trait Association ◽

Population Structure Analysis ◽

Marker Loci ◽

Drought Tolerance Indices ◽

Tolerance Indices

Abstract Background: Little information is available on the application of marker-trait association (MTA) analysis for traits related to drought tolerance in smooth bromegrass. The objectives of this study were to identify marker loci associated with important agronomic traits and drought tolerance indices as well as fining stable associations in a diverse panel of polycross derived genotypes of smooth bromegrass. Phenotypic evaluations were performed at two water environments (normal and drought stress) during two years; and association analysis was done with 626 SRAP markers. Results: The results of population structure analysis identified three main subpopulations possessing significant genetic differences. Under normal irrigation, 68 and 57 marker-trait associations were identified using general linear model (GLM) and mixed linear mode1 (MLM), respectively. While under deficit irrigation, 61 and 54 markers were associated with the genes controlling the studied traits, based on these two models, respectively. Some of the markers were associated with more than one trait. It was revealed that markers Me1/Em5-11, Me1/Em3-15, and Me5/Em4-7 were consistently linked with drought-tolerance indices. Conclusion: Following marker validation, the MTAs reported in this panel could be useful tools to initiate marker-assisted selection (MAS) and targeted trait introgression of smooth bromegrass under normal and deficit irrigation regimes, and possibly fine mapping and cloning of the underlying genes and QTLs.

Download Full-text