Characterization of ASR gene and its role in drought tolerance in chickpea (Cicer arietinum L.)

Abstract

Chickpea has a profound nutritional and economic value in vegetarian society. Continuous decline in chickpea productivity is attributed to insufficient genetic variability and different environmental stresses. Chickpea like several other legumes is highly susceptible to terminal drought stress. Multiple genes control drought tolerance and ASR gene plays a key role in regulating different plant stresses. The present study describes the molecular characterization and functional role of Abscissic acid and stress ripening (ASR) gene from chickpea (Cicer arietinum) and the gene sequence identified was submitted to NCBI Genbank (MK937569). Molecular analysis using MUSCLE software proved that the ASR nucleotide sequences in different legumes show variations at various positions though ASR genes are conserved in chickpea with only few variations. Sequence similarity of ASR gene to chickpea putative ABA/WDS induced protein mRNA clearly indicated its potential involvement in drought tolerance. Physiological screening and qRT-PCR results demonstrated increased ASR gene expression under drought stress possibly enabled genotypes to perform better under stress. Conserved domain search, protein structure analysis, prediction and validation, network analysis using Phyre2, Swiss-PDB viewer, ProSA and STRING analysis established the role of hypothetical ASR protein NP_001351739.1 in mediating drought responses. NP_001351739.1 might have enhanced the ASR gene activity as a transcription factor regulating drought stress tolerance in chickpea. This study could be useful in identification of new ASR genes that play a major role in drought tolerance and also develop functional markers for chickpea improvement.

Response of chickpea to varying moisture stress conditions in Ethiopia

“…Cultivars showing superior overall performance under severe stress condition are potentially suitable for production in drought‐prone growing environments in Ethiopia. The cultivars can also be used as donor parents in the breeding programs where novel adaptive traits can be transferred into elite lines for enhancing drought tolerance (Maqbool et al., 2017; Sachdeva et al., 2020). Most importantly, they are extremely useful in basic studies of trait discovery in the pre‐breeding programs.…”

Allelic Diversity at Abiotic Stress Responsive Genes in Relationship to Ecological Drought Indices for Cultivated Tepary Bean, Phaseolus acutifolius A. Gray, and Its Wild Relatives

“…Various candidate genes have been identified [ 29 ], most with moderate effects as expected for a complex adaptive trait [ 26 ]. Some mechanisms of drought tolerance are controlled through an abscisic acid (ABA) responsive pathway [ 30 ]; among which Asr (abscisic acid, stress, ripening induced) transcription factors are components [ 31 ] of the ABA-dependent pathway [ 32 ] that interact with ABA-responsive element promoters [ 33 ] for sucrose synthase genes [ 34 ]. Asr1 has been under positive natural selection for drought adaptation in wild common beans from semi-mesic to dry habitats [ 35 ] indicating its importance for breeding or gene editing in the future and for the present study.…”

Assessment of Variability and Genetic Parameters in Agro-Physiological Traits of Chickpea (Cicer arietinum L.) under Rainfed Condition

“…Eight genotypes viz., JG 6, KAK 2, Green Gram, IG 593, IG 370, JG 412, JG 130 and JG 322 showed higher relative water content. Sachdeva et al [17] concluded that maintaining higher RWC (%) enabling genotypes to perform better in terms of physiological processes under stress and decreasing in RWC signifying their vulnerability to drought stress. The values of mean and range revealed that there were wide ranges of genetic variability among genotypes for various agrophysiological traits.…”