Key Inbred Lines Cluster Analysis and Heterosis Model Analysis of Different Period Maize Hybrids in China

Heterosis groups were classified by cluster analysis with SSR based on 32 maize inbred lines of different period utilized widely hybrids maize production in China.The results showed that 32 inbred lines could be classified into 6 groups.GroupⅠconsisting of Huangzaosi,Huangyesi,Chang7-2,Ji444,Xi502,K12,Ye81515 and LX9801 was included in the Tangsipingtou heterosis group;group Ⅱconsisting of Ye478,Zheng58,U8112,C8605-2 and PH6WC was included in the Reid heterosis group;group Ⅲ consisting of Yuzi87-1,Shen137,Qi319,X178 and Dan598 belonged to a new heterosis group PN78599 which different from other groups;group Ⅳ consisting of Aijin525,Ye52106,Zong31 and HuangC belonged to a integrative heterosis group;group Ⅴ consisting of Ben7884-7ht,C103,Mo17,Mo17ht,Huotanghuang,Zi330 and PH4CV belonged to Lancaster heterosis group;group Ⅵ consisting of E28,Dan340 and Ye107 belonged to Lvdahonggu group.The six groups by cluster analysis with SSR markers conformed to the pedigree method on the whole,but it also expressed differences,the result of study indicated that it was practical to group maize inbred lines by SSR marker.The evolvement of different period maize hybrid's heterosis model indicated that Reid×Tangsipingtou and Reid×Lancaster were the primary model on heterosis application in China in the future.