Maize Genetic Diversity and Heterosis Group

  • Haitao Guan
Keywords: Maize Hybrids, Genetic Diversity, Heterosis Groups, Molecular Markers


The purpose of this article is to collect maize species resources with rich genetic diversity, and divide the
resources into heterosis groups to significantly improve breeding efficiency and the advantages of heterosis
groups. The genetic diversity of 33 maize inbred lines was studied using SSR markers. A total of 289 allelic
variants were detected in the test materials with 72 pairs of primers. 2 to 7 alleles were detected for each pair of
primers, with an average of 4.01. The genetic similarity coefficient of the 33 inbred lines varied from 0.5866 to
0.9247, with an average of 0.7056. Although the average genetic similarity coefficient was large, the range of
variation was also large, indicating that there were abundant genetic diversity among the tested inbred lines. Sex.
The experiment showed that through analysis of genetic distances between the parents of 22 approved maize
varieties, it was found that the genetic distance between SSR molecular markers and heterosis showed a certain
relationship, and the parents of the extended combination had larger genetic distances, but not the largest genetic
distance. High-yielding combinations were assembled among all inbred lines, and the genetic distance of the
parents of some combinations of Xiyu 3, Qisan Single Cross, Chuandan 18, Chuandan 13, Chuandan 16 and
Yandan 14 was less than the average Genetic distance did not show obvious linear relationship between genetic
distance and heterosis. In addition, 119 hybrid combinations were formulated in 24 inbred lines according to the
incomplete two-row cross design. Using the UPGMA method, 17 inbred lines were classified into 6 categories
based on the special combining ability of yield. The classification results and inbred lines the kinship
relationship is basically the same, and the special cooperation force between groups is greater than the special
cooperation force within groups.