Rising global mean temperatures open opportunities in high‐altitude production systems for temperature‐sensitive crops such as lowland rice. Currently, the cropping window for rice in higher altitudes is still narrow, and thus, genotypes that tolerate a certain degree of chilling are needed to achieve their potential yield. Final yield depends on the interaction between genotype and environmental conditions. Exposing the genotype to a wide range of environments is a way to evaluate its adaptability into an expanding cropping calendar. Over a 2‐year period, an experiment was conducted in lowland rice systems in Madagascar at two locations differing in altitude. Twenty genotypes with contrasting levels of tolerance to low temperature were sown monthly in a non‐replicated rice garden trial. Plant development was monitored and yield and yield components were determined. Yield stability across the different growing environments was investigated. While crop duration was affected by sowing dates and altitude, yield was mainly determined by sowing date. Panicle number per m² and number of spikelets per panicle were the most limiting factors for yield potential in mid‐altitude, while in high altitude, yield was mainly limited by spikelet fertility. Resulting cropping calendar and genotype recommendations are discussed.

中文翻译：

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高海拔作物系统中低地水稻的基因型产量响应

全球平均温度的升高为高地生产系统打开了对温度敏感作物（如低地水稻）的机会。当前，高海拔水稻的种植窗口仍然很窄，因此，需要具有一定程度耐寒性的基因型才能实现其潜在产量。最终产量取决于基因型和环境条件之间的相互作用。将基因型暴露于广泛的环境中是一种评估其适应不断扩大的种植日历的适应性方法。在两年的时间里，在马达加斯加的低地水稻系统中，在两个海拔高度不同的地方进行了一项实验。在一项非重复的水稻园试验中，每月播种二十种具有相对低温耐受性的基因型。监测植物发育并确定产量和产量成分。研究了不同生长环境下的产量稳定性。作物持续时间受播期和播种高度的影响，而产量主要取决于播种期。每米穗数²和每穗小穗数是中海拔产量潜力的最大限制因素，而在高海拔地区，产量主要受小穗繁殖力的限制。讨论了作物日历和基因型建议。