Supplementary tables.

The current instability of water resources poses a major challenge and may lead to a food shortage crisis. To address this issue and to cope with the challenges of future extreme weather events and insufficient water resources, it is imperative to develop water-saving cultivation measures. This study used the long-term historical yield data of three rice varieties, TK9, TNG67 and TCS10, from an agricultural research station in Taiwan, simulated two water-saving cultivation experiments using the DSSAT crop model, and established a yield model based on the water-saving ratio, aiming to recommend appropriate irrigation water for Taiwan rice varieties. The goal was to save water while ensuring that the yield is not affected. Through water-saving cultivation simulation experiments, we estimated that under the condition of maintaining more than 90% of rice yield, water-saving irrigation treatment of rice in two different cropping seasons can save about 48% to 100% and 42% to 61% of irrigation water respectively. For irrigation treatment during sensitive growth stages, significant water-saving effects can be achieved, which are about 40% to 75% and 55% to 91% respectively. This study suggests that in the case of water shortage, it is possible to consider moderately increasing the water-saving ratio and implementing irrigation during sensitive growth periods, so as to effectively cope with future water shortage scenarios and achieve sustainable rice production while saving water resources.当前水资源不稳定态势构成重大挑战，或引发粮食短缺危机。为解决该问题、应对未来极端天气事件与水资源不足带来的挑战，研发节水栽培措施势在必行。本研究采用中国台湾地区某农业研究站的3个水稻品种（TK9、TNG67、TCS10）的长期历史产量数据，借助DSSAT作物模型（DSSAT crop model）开展两项节水栽培模拟实验，并基于节水率构建产量模型，旨在为台湾地区水稻品种推荐适宜灌溉水量。本研究的核心目标是在保障水稻产量不受影响的前提下实现节水。通过节水栽培模拟实验，本研究估算得出：在维持水稻产量超90%的前提下，两个不同种植季的水稻节水灌溉处理可分别节省约48%~100%与42%~61%的灌溉水量；若在水稻敏感生育期实施灌溉，则可实现显著节水效果，节水率分别约为40%~75%与55%~91%。本研究建议，在水资源短缺场景下，可考虑适度提高节水率，并在敏感生育期实施灌溉，从而有效应对未来水资源短缺情势，在节约水资源的同时实现水稻可持续生产。