Abstract:

To elucidate the common traits underlying the coordinated achievement of high yield and superior grain quality in super three-line indica hybrid rice, this study compiled data from 85 super three-line indica hybrid rice cultivars released in China between 2005 and 2025. Based on yield and amylose content as key indicators, cluster analysis classified these cultivars into six distinct groups: hard-texture low-yield, medium-hard-texture low-yield, hard-texture medium-yield, medium-hard-texture medium-yield, medium-hard-texture high-yield, and soft-texture high-yield. Systematic comparisons were conducted on growth characteristics, yield components, and grain quality traits across the six groups to identify the common characteristics of soft-texture high-yielding cultivars, thereby providing a theoretical basis for breeding and cultivation practices. The results demonstrated that the soft-texture high-yield and medium-hard-texture high-yield groups achieved significantly higher yields, exceeding those of the medium-yield groups by 12.89%-16.16% and the low-yield groups by 32.50%-35.93%. The soft-texture high-yield group exhibited the lowest amylose content, which was significantly reduced by 13.78%-21.29% compared with other groups, while no significant differences in amylose content were observed among the remaining groups. Regarding yield components, the soft-texture high-yield group had the lowest number of productive panicles, which was not significantly different from that of the medium-hard-texture high-yield group but was significantly lower than that of the low-yield groups by 17.69%-20.17%. This group also recorded the highest spikelet number per panicle, showing no significant difference from the medium-hard-texture high-yield group but increasing significantly by 12.65%-39.42% relative to the other groups. The total number of spikelets was highest in the soft-texture high-yield group, representing significant increases of 8.56% and 13.39% over the medium-hard-texture medium-yield and medium-hard-texture low-yield groups, respectively. The 1000-grain weight was highest in this group, with no significant differences observed among medium-and high-yield groups but showing significant increases of 9.21%-11.52% compared with the low-yield groups. No significant differences in grain filling percentage were detected among the six groups. In terms of milling quality, the brown rice rate of the soft-texture high-yield group did not differ significantly from that of the other groups. Its milled rice rate was only significantly higher (by 3.11%) than that of the hard-texture medium-yield group, whereas its head rice rate was significantly elevated by 4.70%-20.38% relative to all other groups. Regarding cooking and appearance qualities, no significant differences were found in protein content, alkali spreading value, or gel consistency among the groups. Although the soft-texture high-yield group tended to exhibit a reduced length-to-width ratio and chalky grain rate, these differences were not statistically significant. However, its chalkiness degree was significantly decreased by 32.96%-42.29% compared with all other groups except the medium-hard-texture high-yield group. Principal component analysis revealed that spikelet number per panicle, total spikelet number, productive panicle number, and 1 000-grain weight were the primary determinants of yield, whereas gel consistency, amylose content, brown rice rate, milled rice rate, length-to-width ratio, alkali spreading value, and chalkiness degree were the main contributors to grain quality. Correlation analysis indicated that in the soft-texture high-yield group, grain yield was significantly positively correlated with growth duration, plant height, panicle length, spikelet number per panicle, total spikelet number, 1 000-grain weight, head rice rate, alkali spreading value, and gel consistency. Conversely, yield was significantly negatively correlated with amylose content, chalkiness degree, and chalky grain rate. In conclusion, compared with other cultivar types, soft-texture high-yielding super three-line indica hybrid rice achieve high yields primarily through significant increases in 1 000-grain weight and spikelet number per panicle, leading to a marked rise in total spikelet number, while maintaining a relatively high grain filling percentage. Concurrently, these cultivars demonstrate synergistic improvements in milling quality (high head rice rate) and appearance quality (low chalkiness degree and a trend toward rounder grains), coupled with a “soft-texture” cooking and eating profile. These advantages are associated with a moderately extended growth duration and increased plant height. Therefore, the promotion of soft-texture high-yielding super three-line indica hybrid rice cultivars facilitates the efficient utilization of temperature and light resources, improves eating quality, and ultimately achieves the coordinated enhancement of both grain quality and yield.

Key words: super three-line indica hybrid rice, soft and high-yield synergy, yield components, grain quality traits, agronomic traits

摘要：

为明确超级三系杂交籼稻高产与优质协同的品种共性特征，本研究收集了2005—2025年我国85个超级三系杂交籼稻品种数据，以产量和直链淀粉含量为关键指标，采用聚类法将这85个品种划分为偏硬质低产、硬质低产、偏硬质中产、硬质中产、偏硬质高产和软质高产6种类型。系统比较了不同类型品种在生长特性、产量构成及品质性状上的差异，旨在筛选软质高产型品种的共性特征，为育种与栽培提供依据。结果表明，软质高产型和偏硬质高产型品种的产量较高，较中产型品种显著高12.89%~16.16%，较低产型品种显著高32.50%~35.93%；软质高产型品种直链淀粉含量最低，较其他类型品种显著降低13.78%~21.29%，其余类型间无显著差异。产量构成方面，软质高产型品种的有效穗数最低，与偏硬质高产型品种无显著差异，较低产型品种显著减少17.69%~20.17%；每穗粒数最高，与偏硬质高产型无显著差异，较其余类型品种显著增加12.65%~39.42%；总颖花数最高，较偏硬质中产型和偏硬质低产型品种分别显著增加8.56%和13.39%；千粒重最高，与中、高产型品种无显著差异，较低产型品种显著提高9.21%~11.52%；各类型间结实率差异未达显著水平。加工品质方面，软质高产型品种的糙米率与其他类型无显著差异；精米率仅较硬质中产型品种显著提高3.11%；整精米率较其他类型品种显著提高4.70%~20.38%。蒸煮与外观品质方面，各类型品种蛋白质含量、碱消值、胶稠度无显著差异；软质高产型品种的长宽比、垩白粒率与其他类型品种相比有降低趋势，但未达显著水平；垩白度较其他类型品种（除偏硬质高产型品种外）显著降低32.96%~42.29%。主成分分析显示，产量的主要决定因子依次为每穗粒数、总颖花数、有效穗数和千粒重；品质的主要决定因子为胶稠度、直链淀粉含量、糙米率、精米率、长宽比、碱消值及垩白度。相关性分析表明，软质高产型品种的产量与生育期、株高、穗长、每穗粒数、总颖花数、千粒重、整精米率、碱消值及胶稠度呈显著正相关，而与直链淀粉含量、垩白度及垩白率呈显著负相关。综上，相较于其他类型品种，软质高产型超级三系杂交籼稻在保持较高结实率的基础上，通过显著增加千粒重与每穗粒数，进而明显提高总颖花数，最终实现高产；同时协同提升了加工品质（高整精米率）与外观品质（低垩白度、粒形趋圆），蒸煮食味趋于“软质化”，生育期适度延长、株高增加。可见，推广软质高产型超级三系杂交籼稻品种有利于高效利用温光资源、改善稻米口感，实现优质与高产的协同提升。

关键词: 超级三系杂交籼稻, 软质高产, 产量构成, 品质性状, 农艺性状