Effect of Elevated Temperature on Rice Phenology and Yield

At present in the context of climate change, temperature is one of the most important environmental factors influencing the rice crop growth, development, and yield. The duration of each phenological stage is influenced by temperature which has direct impact on yield. The objective of this study is to provide an overview of the influence of elevated temperature on rice phenology and accumulated growing degree days. The experiment was conducted during Kharif 2012 under temperature control chamber, in which temperature is elevated from the ambient level (2°C and 4°C) for the entire crop growth period. The results showed that the days taken to attain maturity was less under elevated temperature of 4°C (96 days) and 2°C (102 days) when compared to the ambient temperature (108 days). The accumulated growing degree days were higher under elevated temperature of 4°C and nearer value for 2°C viz., 1641 and 1583 respectively from that of ambient. Under elevated temperature of 4°C and 2°C, the grain yield was 23 and 13.3 percent less from the ambient. The highest grain yield is from the treatment under ambient temperature with 6.2 t/ha followed by 5.3t/ha under 2oC level and 4.7 t/ha at 4oC level. The yield loss under elevated temperature is due to the sterile florets and lesser crop duration.