Effect of Different Biochemical Parameters and Antioxidant Enzymes Activities on Drought Indices in Chickpea (Cicer arietinum L.)

Background: Drought is the foremost environmental restraint that effects the growth and yield of chickpea. The mechanism of response to drought differs with genotype and growth stages of individual crop species. The activation of antioxidant enzymes is an alternate defensive system against oxidative stress that ultimately decide development of putative drought tolerant mechanism. Methods: Eighty-three chickpea genotypes were grown under normal and drought stress conditions and leaf samples were used to estimate different biochemical parameters including total sugar, lipid peroxidation (MDA), chlorophyll, proline and protein along with estimation of activities of different antioxidant enzymes viz., catalase (CAT) (EC 1.11.1.6), ascorbate peroxidase (APX) (EC 1.11.1.11), superoxide dismutase (SOD) and peroxidase (POX). Result: Positively significant correlation was found among proline under control with proline underwent stress (r=0.441), MDA under stress with proline under control (r=0.365) and MDA under control (r=0.336) at 1% level of significance. Positively significant correlation was also investigated between SOD under stressed condition with SOD under control (r=0.665), POX (0.449) and APX under stress (0.423), CAT under control (0.471) and CAT under stress condition (0.374) at 1% probability level. Heatmaps along with dendrograms represented expression levels of different antioxidant enzymes activities that showed variations among different genotypes. In conclusion. total sugar, proline and Malondialdehyde, have been increased under drought stressed condition whilst total chlorophyll and protein were decreased. While antioxidant enzymes viz., POX, APX, CAT and SOD levels increased under drought stressed conditions.