STUDY ON MORPHO-PHYSIOLOGICAL TRAITS, YIELD AND WATER-USE EFFICIENCY OF WHEAT UNDER WATER STRESS CONDITION

Abstract

The present study was conducted at Crop Physiology and Ecology Laboratory and research field, Hajee Mohammad Danesh Science and Technology University (HSTU), Dinajpur during November 29, 2015 to March 24, 2016 to study on morpho-physiological traits, yield and water-use efficiency of wheat under water stress condition. Three experiments were carried out under this study. The experiments were laid out in completely randomized design with three replications. Speed of germination as expressed by rate of germination, co-efficient of germination and germination vigor index of all wheat genotypes was delayed under polyethylene glycol (PEG) induced water stress as compared to control. Shoot length, root length, shoot to root ratio, shoot dry weight, root dry weight and seed metabolic efficiency of 5 days old seedlings were found to be reduced due to water stress. But the degree of reduction of these parameters in relation to water stress was not similar for all wheat genotypes. Based on relative injury (%) wheat genotypes BAW-1177 and BARI Gom-29 were considered as drought tolerant whereas, ESWYT-29 considered as drought susceptible and BARI Gom-28 was moderately drought tolerant. Drought tolerant wheat genotypes showed greater ability to retain water in leaf, greater stability of flag leaf chlorophyll, greater ability to keep the canopy cooler and higher level of proline in flag leaf compared to sensitive genotype under water stress condition. Plant height, spike length, spike plant-1, spikelet number spike-1, grains spike-1 grains spikelet-1, grain weight spike-1 and 100-seed weight were higher in drought tolerant genotypes compared to drought sensitive genotype at both well-watered and water stress conditions. At well-watered and water stress conditions, BAW-1177 attained the highest shoot biomass and seed yield plant-1 followed by BARI Gom-28 and BARI Gom-29 whereas, ESWYT-29 had the lowest biomass and seed yield. Drought reduced the HI for BARI Gom-28 and ESWYT-29 but it increased for BAW-1177 and BARI Gom-29 compared to well-watered condition. In water-use efficiency at seed yield level and biomass level all the genotypes showed slight increment under drought condition compared to wellwatered condition. Therefore, BAW-1177 had the highest wateruse efficiency and ESWYT-29 had the lowest water-use efficiency at both well-watered and water stress conditions. The order of drought tolerance based on above ground biological yield and grain yield was BAW 1177 > BARI Gom-29 > BARI Gom-28 > ESWYT-29