Physiological, biochemical and molecular responses of lentil ( Lens culinaris Medik.) genotypes under drought stress

Lentil (Lens culinaris Medik.) is an important pulse crop in India. It is moderately tolerant to drought, however intermittent and terminal drought significantly reduce lentil productivity. Selection of appropriate parent for breeding drought resistant variety is a challenging task. Thus, in the present work drought response of eight lentil genotypes (GP3690, LL1136, GP3643, NDL908, KLS218, IC248956, PL230, L4076) has been analysed, by imposing drought stress using PEG 6000 (18% w/v) for 15 days. Various physiological (stomatal density, relative water content) and biochemical parameters (total chlorophyll, total soluble sugar, anthocyanin and proline contents, lipid peroxidation, superoxide dismutase and catalase activities) were analysed under drought stress. These eight genotypes were further evaluated by analysing expression of drought stress marker genes (DREBs and RDs) which suggested genotypes GP3690 as drought susceptible (DS) and genotypes GP3643 and IC248956 as drought tolerant (DT). Relative expression of forty-three drought responsive genes related to various molecular functions, like biosynthetic process, redox homeostasis and defence related genes were evaluated in these three genotypes, which revealed that the tolerant genotypes alters the metabolic and biosynthesis processes of plant to overcome drought. This study provides basic information on drought tolerance capacity of the genotypes which may be further ascertained at field level.