Quantifying the Yield Sensitivity of Modern Rice Varieties to Warming Temperatures: Evidence from the Philippines

This study examines the relationship between yields of modern rice varieties and three major weather variables | maximum temperature, minimum temperature, and precipitation. Data from a long-running farm-level survey in the Philippines, with rich information on planted rice varieties, allows us to estimate fixed effect econometric models of rice yields. We find that increases in temperature, especially minimum temperatures, have substantial negative impacts on rice yields. Yield response to temperatures vary across different varietal groups. Early modern varieties, bred primarily for higher yields, pest resistance, and/or grain quality traits, demonstrate improved heat-stress resistance relative to traditional varieties. Moreover, the most recent varietal group bred for better tolerance to abiotic stresses are even more resilient to warming temperatures. These results provide some evidence that public investments in breeding rice varieties more tolerant to warming temperatures have been successful, and continued investments in these breeding efforts are warranted.