The Impact of Drought Stress on some Morpho-Physiological Traits and RAPD Markers in Wheat Genotypes

The present study was designed to evaluate the changes in different physiological traits such as proline content, cell membrane stability, relative water content and chlorophyll content under drought stress in sixteen wheat genotypes. Wheat genotypes (99FJ-03, Marvi-2000, WC- 13, WC-24, WC-19, Faisalabad-85, Kaghan, Bahawalpur, Zarlashta, Punjab-96, Shafaq, Maxi-pak, WC-20, Chenab-70, AUR-0809, Chakwal) were sown during rabiseason of 2013-14 following randomized complete block design with three replications. Drought stress was induced by withholding water for 30 days at heading and anthesis stage. Genotypes were significant for different physiological traits like relative water content, proline content, cell membrane stability and chlorophyll content under drought stress which indicated that some genotypes were more tolerant against drought stress than others. Among tested wheat genotypes, Maxi-Pak was found to be potential variety for relative water content, cell membrane stability, chlorophyll content and yield. Hence, it can be used in future wheat breeding programme for developing drought tolerant genotypes.SAARC J. Agri., 16(1): 1-6 (2018)

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Molecular studies for drought tolerance in some Egyptian wheat genotypes under different irrigation systems

Open Agriculture ◽

10.1515/opag-2020-0030 ◽

2020 ◽

Vol 5 (1) ◽

pp. 280-290 ◽

Cited By ~ 1

Author(s):

Hani A. Mansour ◽

Salwa El Sayed Mohamed ◽

David A. Lightfoot

Keyword(s):

Water Stress ◽

Drought Stress ◽

Grain Yield ◽

Drip Irrigation ◽

Rapd Markers ◽

Irrigation System ◽

Water Productivity ◽

Sprinkler Irrigation ◽

Irrigation Systems ◽

Wheat Genotypes

AbstractThis research work was carried out to evaluate drought stress for the differentiation of bread wheat (Triticum aestivum L.) genotypes in their ability to tolerate drought. An experiment was carried out on six genotypes (‘Sides 1’, ‘Shindwell 1’, ‘Gemmiza 9’, ‘Sakha 93’, ‘Saheel 1’ and ‘Masr 2’). A randomized complete block design with three replications along two separate tests under the drip and the sprinkler irrigation systems was used in this experiment. One of the irrigation treatments applied the normal amount of irrigation water and the other applied end-season drought stress conditions through two successful agricultural seasons 2016/2017 and 2017/2018. The impact on biomass, grain yield and water productivity of the six genotypes was measured. Random amplified polymorphic DNA (RAPD) markers were used to evaluate genetic variation among the six genotypes. PCR–RAPD analysis showed that there were several differences in both the size and number of bands between the varieties. Based on these markers, genetic similarity coefficients were calculated and a dendrogram was constructed. The dendrogram analysis delineated three major clusters. The current study showed that RAPD markers are useful in the assessment of the genetic diversity among the wheat genotypes. The drip irrigation system gave the highest values of both the biomass and the grain yield for the six genotypes, while the sprinkler irrigation gave the lowest values. Comparing the six genotypes in terms of the biomass, grain yield and water productivity, it was concluded that, the highest water productivity (WP) genotype was Sides 1, except during water stress with the sprinkler irrigation system. It was followed by genotype Sakha 93, then genotype Shindwell 1, while genotype Gemmiza 9 gave the lowest in all cases, except without water stress under drip irrigation.

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Improving Drought Tolerance in Mungbean (Vigna radiata L. Wilczek): Morpho-Physiological, Biochemical and Molecular Perspectives

Agronomy ◽

10.3390/agronomy11081534 ◽

2021 ◽

Vol 11 (8) ◽

pp. 1534

Author(s):

Chandra Mohan Singh ◽

Poornima Singh ◽

Chandrakant Tiwari ◽

Shalini Purwar ◽

Mukul Kumar ◽

...

Keyword(s):

Drought Stress ◽

Drought Tolerance ◽

Crop Production ◽

Mitigation Strategies ◽

Theoretical Research ◽

Whole Genome Sequence ◽

Complex Nature ◽

Drought Tolerant ◽

Breeding Programmes ◽

The Impact

Drought stress is considered a severe threat to crop production. It adversely affects the morpho-physiological, biochemical and molecular functions of the plants, especially in short duration crops like mungbean. In the past few decades, significant progress has been made towards enhancing climate resilience in legumes through classical and next-generation breeding coupled with omics approaches. Various defence mechanisms have been reported as key players in crop adaptation to drought stress. Many researchers have identified potential donors, QTLs/genes and candidate genes associated to drought tolerance-related traits. However, cloning and exploitation of these loci/gene(s) in breeding programmes are still limited. To bridge the gap between theoretical research and practical breeding, we need to reveal the omics-assisted genetic variations associated with drought tolerance in mungbean to tackle this stress. Furthermore, the use of wild relatives in breeding programmes for drought tolerance is also limited and needs to be focused. Even after six years of decoding the whole genome sequence of mungbean, the genome-wide characterization and expression of various gene families and transcriptional factors are still lacking. Due to the complex nature of drought tolerance, it also requires integrating high throughput multi-omics approaches to increase breeding efficiency and genomic selection for rapid genetic gains to develop drought-tolerant mungbean cultivars. This review highlights the impact of drought stress on mungbean and mitigation strategies for breeding high-yielding drought-tolerant mungbean varieties through classical and modern omics technologies.

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Comparing transcriptional responses to Fusarium crown rot in wheat and barley identified an important relationship between disease resistance and drought tolerance

BMC Plant Biology ◽

10.1186/s12870-020-02818-1 ◽

2021 ◽

Vol 21 (1) ◽

Author(s):

Z. Y. Su ◽

J. J. Powell ◽

S. Gao ◽

M. Zhou ◽

C. Liu

Keyword(s):

Drought Stress ◽

Drought Tolerance ◽

Crown Rot ◽

Differentially Expressed ◽

Transcriptional Responses ◽

Drought Treatment ◽

Crop Species ◽

Fusarium Crown Rot ◽

Important Relationship ◽

The Impact

Abstract Background Fusarium crown rot (FCR) is a chronic disease in cereal production worldwide. The impact of this disease is highly environmentally dependant and significant yield losses occur mainly in drought-affected crops. Results In the study reported here, we evaluated possible relationships between genes conferring FCR resistance and drought tolerance using two approaches. The first approach studied FCR induced differentially expressed genes (DEGs) targeting two barley and one wheat loci against a panel of genes curated from the literature based on known functions in drought tolerance. Of the 149 curated genes, 61.0% were responsive to FCR infection across the three loci. The second approach was a comparison of the global DEGs induced by FCR infection with the global transcriptomic responses under drought in wheat. This analysis found that approximately 48.0% of the DEGs detected one week following drought treatment and 74.4% of the DEGs detected three weeks following drought treatment were also differentially expressed between the susceptible and resistant isolines under FCR infection at one or more timepoints. As for the results from the first approach, the vast majority of common DEGs were downregulated under drought and expressed more highly in the resistant isoline than the sensitive isoline under FCR infection. Conclusions Results from this study suggest that the resistant isoline in wheat was experiencing less drought stress, which could contribute to the stronger defence response than the sensitive isoline. However, most of the genes induced by drought stress in barley were more highly expressed in the susceptible isolines than the resistant isolines under infection, indicating that genes conferring drought tolerance and FCR resistance may interact differently between these two crop species. Nevertheless, the strong relationship between FCR resistance and drought responsiveness provides further evidence indicating the possibility to enhance FCR resistance by manipulating genes conferring drought tolerance.

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Genome-wide SNP discovery, linkage mapping, and analysis of QTL for morpho-physiological traits in rice during vegetative stage under drought stress

Physiology and Molecular Biology of Plants ◽

10.1007/s12298-021-01095-y ◽

2021 ◽

Author(s):

Rizky Dwi Satrio ◽

Miftahul Huda Fendiyanto ◽

Ence Darmo Jaya Supena ◽

Sony Suharsono ◽

Miftahudin Miftahudin

Keyword(s):

Drought Stress ◽

Linkage Mapping ◽

Physiological Traits ◽

Vegetative Stage ◽

Snp Discovery ◽

Genome Wide

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Drought stress increases the expression of barley defence genes with negative consequences for infesting cereal aphids

10.1101/2021.09.12.459767 ◽

2021 ◽

Author(s):

Daniel Leybourne ◽

Tracy Valentine ◽

Kirsty Binnie ◽

Anna Taylor ◽

Alison Jane Karley ◽

...

Keyword(s):

Drought Stress ◽

Aphid Species ◽

Susceptible Variety ◽

Aphid Resistance ◽

Herbivorous Insects ◽

Cereal Aphids ◽

Negative Consequences ◽

Resistant Plant ◽

Negative Effect ◽

The Impact

Crops are exposed to myriad abiotic and biotic stressors with negative consequences. Two stressors that are expected to increase under climate change are drought and infestation with herbivorous insects, including important aphid species. Expanding our understanding of the impact drought has on the plant-aphid relationship will become increasingly important under future climate scenarios. Here we use a previously characterised plant-aphid system comprising a susceptible variety of barley, a wild relative of barley with partial-aphid resistance, and the bird cherry-oat aphid to examine the drought-plant-aphid relationship. We show that drought has a negative effect on plant physiology and aphid fitness and provide evidence to suggest that plant resistance influences aphid responses to drought stress, with the expression of aphid detoxification genes increasing under drought when feeding on the susceptible plant but decreasing on the partially-resistant plant. Furthermore, we show that the expression of thionin genes, plant defensive compounds that contribute aphid resistance, increase ten-fold in susceptible plants exposed to drought stress but remain at constant levels in the partially-resistant plant, suggesting they play an important role in modulating aphid populations. This study highlights the role of plant defensive processes in mediating the interactions between the environment, plants, and herbivorous insects.

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