24-EPIBRASSINOLIDE MODULATES BIOMASS PRODUCTION, GAS EXCHANGE CHARACTERISTICS AND INORGANIC NUTRIENTS IN CANOLA (BRASSICA NAPUS L.) UNDER SALT STRESS

Present research work was designed to appraise the impact of exogenously applied 24-Epibrassinolide (24-EpiBL) in two canola varieties (Brassica napus L.) under salt stress. Seed of both varieties (Cyclone and Dunkled) were acquired from Ayub Agriculture Research Institute (AARI), Faislabad, Pakistan. Ten healthy seeds of each variety were sowed in plastic pots and after 15 days of seed germination, salinity stress was applied at (0 mM and 100 mM NaCl) in the solution of Hoagland nutrients. After salt treatment, 20 days old plants were foliar sprayed with 24-EpiBL at different levels (0, 0.5 and 1 mu mol 24-EpiBL). Salinity stress remarkably declined biomass production, gas exchange parameters, WUE, RWC, root and shoot mineral nutrients (K+ and Ca2+) and their ratios while conc. of Na+ and Cl- ions were improved in root and shoots of each variety. Foliar applied 24-EpiBL lessened the adversities of salinity stress and upgraded the values of the root, shoot length and dry mass, intercellular CO2 conc., rate of photosynthetic activity, rate of transpiration, stomatal conductance, water -use efficiency, leaf relative water content, mineral contents (Ca2+, K+) and nutrients ratios in root and shoots under control and salt-affected situations.

Automated summary

This research investigated the impact of exogenously applied 24-Epibrassinolide (24-EpiBL) on two canola varieties under salt stress. The results showed that salt stress significantly reduced biomass production and mineral nutrient content, but foliar application of 24-EpiBL alleviated the negative effects of salt stress.