Project description:Chickpea (Cicer arietinum) is the third largest legume grown worldwide and are prone to drought and various pathogen infections. These stresses often occur concurrently in the field conditions. Previous studies in other plant species indicated that plant senses concurrently occurring stresses as new state of stress however, the molecular events in response to that is largely unknown. In the present study, we studied the transcriptome changes in chickpea plants exposed to combination of drought stress and a potential wilt pathogen, Ralstonia solanacearum by microarray analysis. Chickpea plants were exposed to short duration individual drought (SD-drought, soil field capacity, FC-35%), long duration individual drought (LD-drought, FC-30%), short duration individual pathogen stress (SD-pathogen = 2 days pathogen infection), long duration individual pathogen stress (LD-pathogen = 4 days of infection) and short duration and long duration combined stress, SD-combined = 2 days of pathogen infection with progressive drought (FC-40% to FC- 35%), LD combined = 4 days of pathogen infection with progressive drought (FC-35% to 30%).Transcriptome analysis for the leaf samples from above treatment were done by microarray analysis using Agilent ChickpeaGXP_8X60K chip. Result indicated presence of specific molecular events and also some common but tailored events in response to combined stress. Global transcriptional analysis in chickpea leaves exposed to individual and combined drought stress and Ralstonia solanacearum infection.
Project description:The total RNA were extracted from pooled tissues of leaves and flowers from several plants of chickpea (Cicer arietinum) using TRIzol reagent (Invitrogen) according to the manufacturer's instructions. Then small RNAs ranging in 18–30 nucleotides were size fractionated electrophoretically, isolated from the gel, ligated with the 5′ and 3′ RNA adapters. The ligated product was reverse transcribed and subsequently amplified using 10–12 PCR cycles. The purified PCR product was sequenced using Illumina Genome Analyzer II. The qualified reads were used to predict microRNAs and phased small interfering RNAs from chickpea. Identification of microRNAs and phased small inferfering RNAs in chickpea (Cicer arietinum) by analyzing small RNA sequencing profiles of leaves and flowers using Illumina GAII.
Project description:Drought is one of the major constraints for crop productivity across the globe. Chickpea (Cicer arietinum L.) is mainly cultivated in the arid and semi-arid tropical regions under rain-fed conditions and drought stress is one of the major constraints, which causes up to 50% yield losses annually. In this study, transcriptomics, proteomics and metabolomics datasets from root tissues of contrasting drought responsive chickpea genotypes, ICC 4958 (drought-tolerant), JG 11 (drought-tolerant); an introgression line, JG 11+ (drought-tolerant) and ICC 1882, (drought-sensitive) under control and stress conditions were generated. The integrated analysis of these multi-omics data revealed complex molecular mechanism underlying drought stress response in chickpea. Transcriptomics integrated with proteomics data identified enhancement of hub proteins encoding isoflavone 4’-O-methyltransferase (Ca_06356), UDP-D-glucose/UDP-D-Galactose 4-epimerase (Ca_15037) and delta-1-pyrroline-5-carboxylate synthesis (Ca_24241). These proteins highlighted the involvement of critical pathways such as antibiotic biosynthesis, galactose metabolism and isoflavonoid biosynthesis in activating drought stress response mechanism. Subsequently, integration of metabolomics data identified six key metabolites (fructose, galactose, glucose, myo-inositol, galactinol and raffinose) that showed enhanced correlation with galactose metabolism. Further, integration of root -omics data together with genomic dataset of the “QTL-hotspot” region harbouring several drought tolerance related traits revealed involvement of candidate genes encoding aldo keto reductase family oxidoreductase (Ca_04551) and leucine rich repeat extensin 2 (Ca_04564). These results from integrated multi-omics approach provided a comprehensive understanding and new insights into the drought stress response mechanism of chickpea.