Moisture stress induced changes in metabolites and cellular functions in chickpea (Cicer arietinum L.) genotypes

The present investigation was aimed to study influence of moisture stress in in vitro identified tolerant (GL28151, RSG963, PDG3) and sensitive (GL22044, GNG1861, PBG1) chickpea genotypes under field conditions. Moisture stress treatments included crop sown with one pre-sowing irrigation (WSVFP), irrigation withheld at flower initiation stage (WSF), irrigation withheld at pod initiation stage (WSP) and control (irrigated as and when required). Osmolytes (in seeds) viz. total soluble sugars, starch, proline, cellular functions; relative water content, membrane permeability index and lipid peroxidation (in leaves), antioxidant enzymes (at pod filling stage) viz. peroxidase, catalase, superoxide dismutase, glutathione reductase were estimated in chickpea seeds under control and stressed conditions. WSVFP was most severely affected by moisture stress followed by WSP and WSF and emphasized on pod intuition stage as critical stage attributable to hindered transport of assimilates towards formation of pods and development of seeds under stress imposed by lack of sufficient moisture. Highest accumulation of total soluble sugars (73.33), starch (73.12), proline (2.04) in mg/g fresh weight, least percentage reduction over control in relative water content (20.3), membrane permeability index (18.8) and minimal lipid peroxidation (31.3) accompanied by significantly enhanced activities of antioxidant enzymes under WSVFP rendered moisture stress tolerance in RSG963. The pronounced cellular damage, lesser alleviation in the content of osmolytes, antioxidant enzymes activity was observed in sensitive genotype GL22044 under stress treatments. High molecular weight protein bands were found either absent or of low intensity in sensitive genotypes (GL22044, GNG1861 and PBG1) under severe stress treatment (WSVFP).