Evaluation And Genetic Diversity Studies On Maize Germplasm Resoures In Guizhou

This experiment selected nineteen maize inbred lines as parent lines including 西₁ 12000-241 , 白 3 杂黄2001-2,79-1E etc. Sixty hybrids were obtained by the method of incomplete diallel cross(9×10). Thirteen Major characters of all hybrids, such as the plant height, ear location height, per plant yield etc., which had been given analysis of combining ability and heredity correlation. In addition, genetic diversity had been given analysis and groups were classified by cluster analysis SSR markers based on 19 maize inbred lines. The results were as follows:(1) As to the character of per plant yield, the results of combining ability analysis showed that the general combining ability of the inbred lines 12, 14, 1, 17, 7 were better than others, the special combining ability of combinations 211,910, 119, 914 , 511 and so on were better than others, the total combining ability of combinations 717,112,414,412,914 etc. were better than others. The results of genotypic variance of combining ability and hereditary capacity estimation showed that selection made in early generations was effective on characteristics of plant height, ear location height, ear diameter and ear rows, but not satisfactory on characteristics of ear length, bald tip length, grains per row, 100-grain weight and bearing grain percentage, and per ear weight and per plant yield should not be selected directly.(2) The analysis of genetic diversity on 19 maize inbred lines had been made by methods of SSR markers. The results based on the method of SSR markers was basically consistent. The significant reference foundation may be provided for parents mating of the hybridized combination in the utilization of corn hybrid vigor.(3) In order to discuss relations between SSR marker and yield heterosis, simple correlation analysis had been respectively made about the genetic distance based on SSR marker with per plant yield of F₁ and SCA of per plant yield. It showed that correlation coefficient between the parent heredity distance and per plant yield of F₁ had not achieved the remarkable level, correlation coefficient between the parent heredity distance and the SCA of per plant yield had achieved the remarkable level,but the decision coefficient (r²=0.083) is actually small. The parent heredity distance obtained by the method of SSR marker accounts for little proportion in the formation of the SCA of per plant yield. So it was not suitable to be used for extrapolating fit or unfit quality of per plant yield of F₁ and SCA of per plant yield.The results indicated that the heredity distance obtained by the method of SSR was just one auxiliary method but cound not easily used for extrapolating yield heterosis between the group parent.