Wheat Physiological Response Under Drought

Abstract

Drought affects wheat crop adversely resulting in reduced growth and productivity. The physio-biochemical adaptations of wheat were studied using ten wheat genotypes namely V-4178, PDW-34, Chakwal-97, Shorawaki, 4098805, Baluchistan, Yecora-70, S-24, SARC-1 and Pasban-90 were sown in pots by using completely randomized design two factorial with three replications. Wheat genotypes were raised at two soil moisture levels i.e. soil moisture level maintained at 100 % field capacity and soil moisture level maintained at 40 % of field capacity. The effects of the two soil moisture levels were studied on wheat genotypes by considering the parameters photosynthetic rate (An), transpiration rate (E), stomatal conductance (gs), stomatal resistance (rs), leaf membrane stability index (LMSI), leaf succulence, relative water content (RWC), epicuticular wax, proline contents, chlorophyll content (SPAD), grain yield, biological yield and harvest index. Drought was considered responsible for the enhanced production of proline and epicuticular wax, reduced stomatal conductance, high stomatal resistance, low photosynthetic and transpiration rate in genotypes as a mechanism to bear the harsh conditions. Low harvest index, biological yield and grain yield were also recorded as a result of drought. Hence, it is concluded that the genotypes resistant to drought performed better under drought conditions due to better physio-biochemical adaptations.