MORPHO-PHYSIOLOGICAL ATTRIBUTES OF RICE CULTIVARS AS INFLUENCED BY ALTERNATE WETTING AND DRYING (AWD) CONDITIONS

Abstract

An experiment was conducted at research field and laboratory in the Department of Crop Physiology and Ecology, Hajee Mohammad Danesh Science and Technology University, Dinajpur, during the period of January to May, 2017 to study morpho-physiological attributes of rice cultivars as influenced by alternate wetting and drying (AWD) conditions. Three varieties viz. BRRI dhan28, BRRI dhan29, BRRI dhan51 and four different irrigations viz. I0- plots were continuously submerged of 3 to 5 cm standing water, I1- application of 5 cm irrigation water when water level in the pipe fell 15 cm below the ground level, I2- application of 5 cm irrigation water when water level in the pipe fell 20 cm below the ground level and I3- application of 5 cm irrigation water when water level fell 25 cm below the ground level were included in the study. The experiment was carried out in a randomized complete block design with three replications. Results showed that the effect of varieties had significant variation in respect of plant height, total tillers hill-1 , number of effective tillers hill-1 , number of non-effective tillers hill-1 , panicle length, grains panicle-1 , unfilled grain panicle-1 , grain yield ha-1 , TDM, LAI, CGR, NAR, straw yield, biological yield and harvest index. The highest number of leaf hill-1 (120.67), plant height (110.36 cm), number of total tillers hill-1 (25.42), number of effective tillers hill-1 (19.92), panicle length (23.99 cm), filled grain panicle-1 (150.33) maximum TDM, maximum LAI, maximum CGR, maximum highest NAR and 1000- grain weight (24.30 g), grain yield t ha-1 (6.7), biological yield t ha-1 (14.81) were recorded from V2 (BRRI dhan29). The highest 1000 grain weight was recorded from V1 (BRRI dhan28). Different intermittent irrigations also showed significant effect on all the parameters. The highest grain yield (6.59 t ha-1 ) was recorded from I0 which was at par with I1. The lowest grain yield (5.07 t ha-1 ) was recorded from I3. The highest grain yield (7.31 t ha-1 ) was obtained from V2 I0 while the lowest grain yield (4.40 t ha-1 ) was obtained from V1 I3. The highest TDM production, LAI, CGR, NAR were obtained from I0. Results of the present study revealed that V2 (BRRI dhan28) variety with I0 irrigation treatment was found to be the best for obtaining maximum grain yield (7.31 t ha-1 ). But V2 I1 performed well without significant yield reduction as compared to V2 I0