Soil phosphorus (P) deficiency is one of the major challenges for the cultivation of rice worldwide because it limits the growth and productivity of the crop. Therefore, the ability to grow in P-deficit soils is an important trait for rice cultivation. O . rufipogon Griff., a wild relative of rice, is a source of genetic variation for low phosphorus tolerance. The present study was undertaken to identify low P stress-tolerant introgression lines by analysing stress tolerance indices of 40 introgression lines of O. rufipogon. The populations were screened under low soil P and normal soil P plots for two growing seasons. Based on yield under stress and normal conditions, we computed different stress indices, including stress tolerance index (STI), tolerance index, yield reduction ratio (YR), stress susceptibility index, yield stability index (YSI), yield index, per cent yield reduction and geometric mean productivity (GMP). The studies of correlation analysis, principal component analysis and clustering revealed that STI, YSI and GMP were ideal indices for the selection of genotypes that performed well under both stress and normal conditions. Based on these indices, introgression lines (IL-24, IL-29 and IL-32) were identified as promising low P tolerant lines, which exhibited better grain yield under both stress (YS) and normal (YP) conditions. These pre-breeding lines serve as valuable genetic resources for low P tolerance in rice breeding programmes across the world.

土壤磷（P）缺乏是全球水稻种植面临的主要挑战之一，因为它限制了作物的生长和生产力。因此，在缺磷土壤中生长的能力是水稻栽培的一个重要性状。哦。rufipogon Griff. 是水稻的野生近缘种，是低磷耐受性遗传变异的来源。本研究旨在通过分析 40 个O. rufipogon基因渗入系的胁迫耐受指数来识别低磷胁迫耐受性基因渗入系。在两个生长季节的低土壤磷和正常土壤磷地块下筛选种群。根据应力和正常条件下的屈服，我们计算了不同的应力指数，包括应力耐受指数（STI）、耐受指数、屈服减少率（YR）、应力敏感性指数、屈服稳定性指数（YSI）、屈服指数、百分比屈服减少和几何平均生产率 (GMP)。相关分析、主成分分析和聚类研究表明，STI、YSI和GMP是选择在胁迫和正常条件下均表现良好的基因型的理想指标。基于这些指标，基因渗入系（IL-24、IL-29 和 IL-32）被确定为有前景的低磷耐受系，它们在胁迫（Y S）和正常（YP ) 条件。这些育种前品系是世界各地水稻育种计划中低磷耐受性的宝贵遗传资源。