Analysis of growth and yield characteristics of rice with different yield levels is very important for the breeding of high-yield rice cultivators. To investigate the yield components’ variation, morphological characteristics of the panicles, leaves, and stems of rice varieties under different yield levels, a two-year field experiment was conducted in Chongqing China. The 20 mid-season Indica hybrid rice varieties were classified into three groups based on yield, comprising high-yield group (HG), mid-yield group (MG), and low-yield group (LG). The main reason for the superior yield of HG is that the varieties of this group had a significantly higher number of effective panicles per unit area than the MG and LG. In plant type factors, the leaf type factors were the most important reason causing yield difference of HG, MG, and LG. The average leaf roll index, average leaf length to width ratio, average leaf base angle, average leaf droop angle, and average leaf pillow distance of the upper three leaves were significantly or significantly negatively correlated with the yield, while the average leaf width, average leaf area, and the average distance of leaf edge were significantly or significantly positively correlated with yield, and the leaf droop angle was the most important plant type factor affecting the yield. Based on these results, we further quantified the plant type factors of HG and constructed an ideal plant type model for high-yield hybrid mid-season rice. Theoretical and practical basis could be provided for breeding mid-season Indica hybrid rice with super-high yield in the future to ensure food security.

中文翻译：

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不同产量水平下杂交中稻生长发育及产量特征比较

分析不同产量水平的水稻的生长和产量特性对于高产水稻中耕者的选育非常重要。为了研究不同产量水平下水稻品种穗，茎，叶的产量组成变化，形态特征，在重庆进行了为期两年的田间试验。20季中In杂交水稻品种按产量分为三类，分别为高产组（HG），中产组（MG）和低产组（LG）。HG产量较高的主要原因是该组品种的单位面积有效穗数比MG和LG高得多。在植物类型因子中，叶片类型因子是引起HG，MG和LG产量差异的最重要原因。上部三叶的平均卷叶指数，平均叶长宽比，平均叶底角，平均叶下垂角和平均叶枕距与产量显着或显着负相关，而平均叶宽，平均叶面积和叶边缘的平均距离与产量显着或显着正相关，叶片下垂角是影响产量的最重要的植物类型因素。基于这些结果，我们进一步量化了HG的植物类型因子，并构建了高产杂交中稻的理想植物类型模型。可以为中期繁殖提供理论和实践依据籼型杂交稻在未来超高产，确保粮食安全。