玉米自交系YJ7不同密度下配合力效应及杂种优势分析

Combination Ability and Heterosis of Maize Inbred Line YJ7 under Different Densities

YJ7是江苏沿江地区农科所选育的优良玉米自交系,利用该自交系已育成一批优良组合。采用NCⅡ设计组配45个杂交组合,研究不同密度下(6.0万、7.5万、9.0万株/hm2)YJ7产量性状的配合力效应及杂种优势。结果表明,除穗粗、穗行数外,YJ7在高密度条件下产量性状一般配合力水平均较高,且随密度的增加而增加;YJ7×Mol17、YJ7×478杂478、YJ7×丹340这3个杂交组合在高密度条件下具有较高的特殊配合力、总体配合力,其杂种优势明显高于其他杂交组合。

YJ7 is one of the super maize inbred lines, and was developed by Jiangsu Yanjiang institute of agri- cultural sciences. Heterosis and combining ability of Y J7 under three different planting densities（60 000, 75 000 and 90 000 plant/ha） were evaluated with 45 hybrid combinations that were grouped by incomplete diallel cross model. The results showed that the general combining ability（GCA） of yield traits of YJ7 was excellent, and the GCA increased along with the increasing of planting density except for that of ear diameter and rows per ear. The combina- tions which were produced by YJ7×Mol17, YJ7×478vs478 and YJ7XDan340 were more preferable than other combi- nations under high density.