生态条件对籼粳交F2代穗部性状与程氏指数的影响

选用籼粳交组合(晚轮422×沈农265)F2为试材,分别在四川、上海、辽宁同年种植,研究在不同生态条件下穗部性状和程氏指数的变化趋势以及二者的关系。结果表明:在四川和上海穗较长、2次枝梗数较多、结实率较低并且与着粒密度呈极显著负相关,而在辽宁穗较短、1次枝梗数较多、结实率较高并且与着粒密度关系不显著。从北到南,程氏指数、叶毛、1-2穗节长、抽穗时壳色和子粒长宽比均呈偏粳分布,并且偏粳程度呈增加趋势。程氏指数与穗颈弯曲度相关性在各地区均未达显著水平;在四川与着粒密度呈显著负相关,与结实率和千粒重呈显著正相关;在上海与结实率呈显著正相关;在辽宁与着粒密度、1次枝梗数、2次枝梗数、粒数呈极显著负相关,与穗长呈显著正相关。因此,水稻超高产育种必须根据生态条件的差异合理地将协调穗部结构与亚种间杂交优缺点互补相结合。

Effect of Ecological Environments on Panicle Traits and Cheng' s Index in the F2 Population of Cross between Indica and Japonica in Rice

The purpose of this study was to analyze the variation tendency of panicle traits and Cheng's index and their relationship under different ecological environments. The F2 population from a cross between Indica variety Wanlun422 and Japonica variety Shengnong265 was used as materials, which was grown in Liaoning, Sichuan and Shanghai in the same year. The results showed that the panicle traits changed significantly in the three places, with the panicle length (PL) longer, the higher secondary branches (SB), but the lower seed setting rate (SSR), and SSR had extremely positive correlation with grain density (GD) in Sichuan and Shanghai. While in Liaoning, the shorter PL, the more primary branches (PB) and the higher SSR, but SSR had no extremely correlation with GD. The frequency distribution of Cheng's index, pubescences of leaf, panicle node length, color of spike and grain length/width under different environments were all japonicalinous, which were increasing from northern to southern of China. The Cheng's index with the panicle curve degree (PCD) had no significant correlation in the three places. In Sichuan the Cheng's index had extremely negative correlation with GD, but it had extremely positive correlation with SSR and 1000-grain weight (TGW). In Shanghai the Cheng's index had extremely positive correlation with SSR. In Liaoning the Cheng's index had extremely negative correlation with GD, PB, SB, Grains, but it had extremely positive correlation with PL. There is no denying the fact that coordinating the improvement of panicle structure and complementation between advantages and disadvantages through subspecies hybrid should accord to local conditions in the super high-yielding rice breeding.