Glycinebetaine induced modulation in oxidative defense system and mineral nutrients sesame ( Sesamum indicum L.) under saline regimes

摘要

Salinity is a wide spread environmental constraint that limits the yield and productivity of crops by altering physiological and biochemical processes at the cellular and whole plant level. Various advancements have been made to quench salinity, of which seed priming is one of the cost-effective strategy. Current research was designed to know the salinity effect on sesame seeds primed with glycinebetaine (GB). The sesame cultivars (TS-5 and TH-6) were primed with two levels of GB (0 mM and 25 mM) for 16 h before sowing in plastic pots pre-filled with sand. After three weeks of sowing, plants were salinized (0 mM and 70 mM NaCl) to evaluate the variation in morphological, biochemical and ionic attributes of both sesame cultivars. The trail was planned up in three-factor factorial completely randomized design (CRD) and data were analyzed by co-stat software. Data of both sesame cultivars were collected after four weeks of establishment of saline regimes. Length and fresh/dry weight of root and shoot, total soluble proteins (TSP), GB and root K + were decreased while catalase (CAT), peroxidase (POD), malondialdehyde (MDA), shoot Na + and K + were increased under saline conditions. Hydrogen peroxide (H 2 O 2 ), POD, CAT, SOD, Total soluble protein (TSP) and GB were increased in GB primed seeds under 70 mM NaCl in both cultivars while fresh/dry weight of root and shoot was increased only in TH-6. Root Na + , root and shoot Ca 2+ contents were not affected. Overall, seed priming with GB imparts positive effect on growth, biochemical and ionic status of both sesame cultivars counteracting the salinity toxicity by balancing TSP, CAT, POD, GB, shoot and root K + , MDA and root Na + . It is suggested that TS-5 showed better response under salinity for most of the attributes studied.