产生F_2群体的海拔对低温条件下水稻穗部性状的影响

Influence of F_2-generated altitude on the panicle traits in rice segregating populations grown at low temperature condition

以小花谷和南34杂交F1在4个不同海拔下自交产生的F2群体为材料,在2 200 m海拔的低温条件下种植分析比较了其主要穗部性状的遗传参数。结果表明:小穗育性和着粒密度对低温冷害都较为敏感,均可用来度量孕穗开花期的耐冷性,并且随着产生F2群体海拔的升高明显增加;然而,穗长和穗节长在中海拔产生的F2群体中表现明显高于在高海拔和低海拔产生的F2群体。此外,在不同海拔产生的F2群体中不同穗部性状的变异系数、遗传率、遗传进度和偏度系数等遗传参数的表现也存在极为明显的差异。研究结果表明产生F2群体的海拔对穗部性状的表现具有非常明显的效应,其中对小穗育性和着粒密度的影响尤为明显。

The genetic parameters of main panicle traits were analyzed in F2 populations planted at low temperature condition with 2 200 m elevation, which populations generated at four different altitudes. The material female parent and male parent are Xiaohuagu and Nan34. The results showed that spikelet fertility and grain density were more sensitive characteristics, could be used as indicators of cold tolerance evaluation at booting stage. The average values of these both traits are increasing with the rising F2-generated altitude; however, the average values of panicle length and panicle node length in the F2 populations generated from middle elevation are significantly higher than in the F2 populations generated from lowest and highest elevation. In addition, the variation coefficient, broad heritability, genetic advance and genetic skewness of the panicle traits in F2 populations are significantly different with F：-generated altitudes. The results indicate that the F2-generated altitude variation had strong effects on panicle traits; the effect is especially obvious on spikelet fertility and grain density.