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Climate warming is a critical environmental issue affecting rice production. However, its effects on cooked rice texture and rice thermal properties remain unstudied in China. To address this gap, we conducted a two-year multi-site field warming experiment using free-air temperature increase facilities across three major Chinese rice cropping systems. Interestingly, warming had a minimal impact on the hardness of cooked rice, while it significantly increased stickiness by an average of 16.3% under warming conditions. Moreover, compared to control treatments, rice flour exhibited a significant increase in gelatinization enthalpy, onset, peak, and conclusion temperatures under warming conditions, with average increments of 8.7%, 1.00 °C, 1.05 °C, and 1.17 °C, respectively. In addition, warming significantly declined the amylose content, remarkedly elevated the protein content and relative crystallinity, and altered the weight distribution of the debranched starch. Correlation analysis revealed significant relationships between cooked rice stickiness, rice flour thermal properties, amylose content, protein content, and partial starch structures. Therefore, warming-induced alterations in rice composition and starch structure collectively enhanced cooked rice stickiness and rice thermal stability. [ABSTRACT FROM AUTHOR]

The effect of climate warming on rice production in China is profound, yet there has been limited research on how it affects the grain yield, nitrogen (N) uptake, and N utilization efficiency (NUtE) of the double-cropping indica rice in South China. To address this gap, we conducted a free air temperature increase (FATI) experiment in Guangdong province during 2020 and 2021. Our findings revealed that warming led to a significant reduction in grain yield, with early rice (ER) and late rice (LR) experiencing average decreases of 5.2% and 6.3%, respectively, compared to control treatments. This decline was primarily attributed to the reduced grain weight of ER and the fewer spikelet numbers per panicle of LR under warming conditions. Although the dry matter translocation, harvest index, and N translocation efficiency of ER remained unchanged under warming conditions, these of LR decreased by an average of 58.1%, 8.8%, and 22.3%, respectively. Additionally, while warming did not affect the N uptake in ER at maturity, it significantly increased the N uptake in LR by an average of 11.0%. Therefore, under warming conditions, the NUtE of both ER and LR was markedly decreased by 6.9% and 15.5% over the two years. These results indicate that climate warming may have significant negative impacts on the grain yield and the NUtE of indica rice within double-rice cropping systems in South China. Understanding these dynamics is vital for maintaining the stability of rice yields in anticipation of future climate warming. [ABSTRACT FROM AUTHOR]