EFFECT OF HEAT AND DROUGHT STRESS ON SEED QUALITY OF WHEAT

Abstract

Seeds of four wheat genotypes (BARI Gom-27, ESWYT (14-15)E-22, BARI Gom30,BARIGom-26) obtained from normal and heat stressed parent plants and seeds of other four wheat genotypes (E-38, BAW-1118, BARI Gom-26, BAW-1130) obtained from well water and water stressed parent plants were tested at the laboratory of Crop Physiology and Ecology department, Hajee Mohammad Danesh Science and Technology University, Dinajpur during the period of November 2016 to January 2017 to observe the effect of heat stress and water deficit stress on seed quality of wheat. Two separate experiments one for heat and another for water stressed seed were laid out in a two factor completely randomized design with three replications. The germination percent of E-22 affected more due to high parent plant temperature than BARI Gom-26, BARI Gom-30 and BARI Gom-27.BARI Gom-27 affected more than three wheat genotypes in relation to coefficient of germination. On the other hand E-22 affected more than other genotypes in relation to vigor index of different wheat genotypes. Seedling dry weight decreased in all wheat genotypes when parent plants experienced heat stress but BARI Gom-27, BARI Gom-30 and E22 affected more than BARI Gom-26.The seed reserve utilization efficiency during germination was decreased significant in all wheat genotype when their experienced heat stress. The seeds of heat stress mother plant released more electrolyte leakage than the seed obtained from non-stress mother plant both at 24 and 48 hours after start of imbibitions. Seedling emergence (%) was decreased all wheat genotype when they were parent experienced heat stress and reduction was significant except BARI Gom-27.The seed quality as expressed by germination (%), speed of germination (coefficient and vigour index), seed reserve utilization efficiency, conductivity of seed leachates and emergence (%) were not significantly affected by the water regimes in which their parent plants were grown. On the hand, normal seedling production, seed density, seed dry weight was significantly influenced by the water regimes in which their parent plants were grown. There was no consistence different between the seeds obtained from well water and water stress parent plant. Finally, the seed quality was reduced in different magnitude in different genotypes due to high parent plant growing temperature but the seed quality was not affected significantly by their parent plant growing water regimes.