Metabolic footprints of chitosan primed red kidney bean under restricted irrigation

Climate change has led to long term shift in temperature and weather regimes leading to unprecedented drought conditions. In this study varying degree of drought stress was imposed by restricting irrigation in red kidney bean along with application of chitosan as seed and foliar prime. LC-MS/MS was used to study the metabolic footprints (flavonoids and anthocyanin) in the red kidney bean varieties (BR 104 and VL Rajma 63). Presence of 14 flavonoid compounds and four anthocyanins (delphinidin>cyaniding>pelargonidin>malvidin) obtained from 0.25% chitosan primed red kidney bean were resolved through LC-MS/MS analysis. The concentration of flavonoid compounds in all the treatments was found in the order of naringenin>quercetin>luteolin>hesperetin>myricetin. Correlation studies revealed strong correlation of 0.95 among catechin-naringenin, galangin-hesperetin and epicatechin-kaempferol in BR 104 variety. Antioxidant activities were investigated by assessing radical scavenging activity, chelating power and reducing power assay in both varieties. Principle component (PC) analysis depicted through biplot showed 44.7% contribution towards PC1 and 28.6% towards PC2 in BR 104 variety. 0.25% chitosan as seed and foliar priming with imposed drought stress was found to improve the antioxidant contents of seed by regulating polyphenols which have diverse role in stress management.