MUNGBEAN VARIETIES EXPRESSED VARIATION IN MORPHOPHYSIOLOGICAL TRAITS AND YIELD UNDER WATER STRESS

Mungbean [Vigna radiata (L)], an important grain legume in Bangladesh, is grown during kharif1 (pre-monsoon) season, when drought is a common abiotic stress. This study was thus conducted in pots inside semi-controlled vinylhouse to assess the effect of water stress on growth and yield of some popular mungbean varieties, viz. BUmug 2, BUmug 4, BARI Mung-5, BARI Mung-6, Binamoog-5 and Binamoog-8. Two water regimes, 80% field capacity (FC; non-stress) and 50% FC (water stress) were maintained. The experiment was laid out in a completely randomized design having four replications. Under water stress the variety Binamoog-5 had the largest leaf area (850.4 cm2 ), while BUmug 4 had the smallest (695.1 cm2 ). At maturity the reduction of shoot dry weight due to water stress was the highest in BUmug 4 (20.6%) while that was the lowest in Binamoog-5 (12.5%). The highest reduction of pod number due to water stress was recorded in BUmug 4 (45.1%) and the lowest was in Binamoog-5 (32.9%) followed by Binamoog-8 (34.5%). The highest reduction in seed number pod-1 due to water stress was in BUmug 4 (21.8%) and the lowest was in Binamoog-5 (16.79%). Water deficit did not exert significant effect on 100-seed weight in the varieties except BUmug 4. Binamoog-5 had the maximum yield plant-1 under both control (12.8 g) and water deficit (7.4 g) conditions followed by Binamoog-8, while BUmug 4 had the lowest in both control (11.6 g) and water deficit (6.3 g) conditions. It was concluded that Binamoog-5 and Binamoog-8 can be potential varieties for field trial for cultivation under water deficit conditions.