Rice yield response to climate variability diverges strongly among climate zones across China and is sensitive to trait variation

Context: The response of rice growth and yield to climate variations in different climate zones and the underlying mechanisms need to be better understood. Objectives: The objectives were to investigate the variations of rice growth and yield with climate variables in different climate zones across China in the past decades and their relations with varietal traits, to gain insights into rice response and adaptation mechanisms to climate variations. Methods: Based on long-term experimental data during 2004-2016 at five representative stations across China, the first-order difference, Mann-Kendall test, multi-collinearity detection, Pearson correlation, stepwise linear regression and structural equation modeling were used. Results: Temperature and precipitation during the growing seasons generally increased although solar radiation declined. Rice yield was more closely associated with temperature during the vegetative growth period at Yanting station, rainfall during the whole growth period at Changshu station and solar radiation during the reproductive growth period at Shenyang station, respectively. Early-season rice yield was more related to solar radiation during the vegetative growth period at Qianyanzhou and Taoyuan stations. Late-season rice yield was more correlated with rainfall during the reproductive growth period at Qianyanzhou station and maximum temperature during the reproductive growth period at Taoyuan station, respectively. Based on the coefficient of determination, climate change and traits explained 13-85% and 47-95% yield variability, respectively. Conclusions: Rice yield response to climate variation diverges strongly among climate zones across China and is subject to trait variation. Significance: This study provides new insights into the mechanisms underlying rice response and adaptation to climate changes, supporting the need for trait-based adaptation strategies to develop new cultivars.