利用SSR标记解析京科968等系列玉米品种的杂优模式

Elaboration of Heterotic Pattern in a Series of Maize Varieties by SSR Markers

利用SSR标记从分子水平上对京科968、京科665、NK718和京农科728系列玉米品种的杂种优势模式进行分析。40对SSR引物在37份供试自交系中共检测出270个等位基因变异,平均每对引物检测出6.75个等位基因,平均多态性信息含量为0.66。UPGMA聚类分析和群体结构分析结果一致,所测自交系被划分成8个杂种优势群,京科968母本京724等5个自交系单独成群,命名为X群;两个骨干父本自交系京92、京2416与自交系黄早四、昌7-2划为一群,同属黄改群(塘四平头群);其他6个群分别为旅大红骨群、瑞德群、P群、兰卡斯特群、改良瑞德群和Iodent群。京科968等系列品种的杂优模式为"X群×黄改群"。通过近年来育种实践和大面积生产证明,"X群×黄改群"已成为我国玉米生产上一种快速上升的主要杂优模式。

The heterosis in a series of maize varieties, including Jingke968, Jingke665, NK718 and Jingnongke728, was analyzed using SSR markers. A total of 270 allelic variations were identified from 37 inbred lines using 40 SSR markers with the average identified alleles of 6.75 per SSR and the average polymorphic information content of 0.66. The UPGMA clustering analysis showed consistent results with the population structure analysis. The tested inbred lines were classified into 8 heterotic groups, including a group consisting of 5 inbred lines to which the female parent of Jingke968, Jing724 belonged, it was designated as X group. Two important inbred lines Jing92 and Jing2416 along with Huangzaosi and Chang7-2 were classified into Huanggai group（or Tangsipingtou）.The rest 6 groups were Ludahonggu, Reid, P, Lancaster, modified Reid and Iodent. According to the SSR markers, the heterot- ic pattern for Jingke968, Jingke665, NK718 and Jingnongke728 was ＂XXHuanggai＂. In recent years, breeding practice and large-scale production substantiated that the pattern of ＂XXHuanggai＂ had become a significant heterotic pattern in the maize production of China.