12:15 PM - 1:00 PM
[P2-17] Effect of Varieties and Organic Manures on Rice Yield and Methane Emission under Water Management
To assess the effect of different organic manure and varieties on methane emission, the pot experiment was conducted at Yezin Agricultural University in wet season, 2016. Organic manures (control-no manure, compost and cowdung), and the two rice varieties (Manawthukha-135 days and IR 50-115 days), were tested. The results showed that in both rice varieties, high grain yield was observed in control compared with manure amendments and the minimum grain yield was observed in cowndung treatment. The rate and cumulative amount of CH4 emissions in Manawthukha was higher than that in IR 50 in accord with yield because of longer growth duration. Although no significant, numerically lowest methane emission was observed in cowdung manure treatment (68.6 g CH4 m-2) for Manawthukha and in cowdung and control treatment (44.6 and 43.4 g CH4 m-2) for IR 50 variety. Based on these results, the field experiment was conducted at Madaya township during the dry and wet seasons, 2017 to find out the water management and different rate of cowdung manure on methane emission and yield of IR 50 rice variety. The higher methane emission was recorded in CF as compared with AWD. In both seasons, the higher grain yields (1.8% in dry and 7.6% in wet) was recorded in AWD than in CF. The higher methane emission was recorded from OM3 and the lower emission from OM0 in both water management practices. In AWD, the methane emission was restricted in the aerated soil condition although higher amount of cowdung manure was added.