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.

Masashi Akao. Maize Genetic Diversity and Heterosis Group. Academic Journal of Agricultural Sciences (2021), Vol. 2, Issue 2: 57-67. https://doi.org/10.38007/AJAS.2021.020206.

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