Comparison Of Genetic Diversity Among Different Types Of Mating Systems In Liriodendron

In this paper,phenotypic variation of growth of progenies of 5 mating types including 14 different mating combinations in Liriodendron at seedling stage and theirs SSR genetic diversity were analyzed.The main results were as follows:Significant variations of growth at seedling stage existed among mating types,mating combinations within types,and among individuals within combinations.The variations of Height and GLD among mating combinations(22.99%,22.36%) were less than that of individuals within combinations,indicating that most phenotypic variation of growth at seedling stage existed among individuals within combinations.The growth of height of 4 combinations (S×O,M×O,S×L,L×O) was larger,exceeded the mean height of all progenies 25.99%, 25.05%,20.45%,14.55%,respectively;The growth of GLD of 4 combinations(L×BM,L×O,M×O,S×O) was larger,exceeded the mean GLD of all progenies 22.22%,20.80%,19.80%,15.49%,respectively.The progenies of 14 mating combinations in Liriodendron were analyzed by using16 polymorphic primers.88 alleles were identified.Average number of alleles per locus was 5.5. Average Shannon index was 1.2312.Expected heterozygosity(He) was 0.6462.Nei genetic diversity index was 0.6454.All these showed that progenies in Liriodendron had high level of genetic diversity.28.95%of genetic variation of progenies in Liriodendron occurred among mating combinations and 71.05%occurred within combinations.There was significant positive correlation between genetic distance between male and female parents and genetic diversity of progenies in Liriodendron with 0.5783 of coefficient and significant level(p) less than 0.05,indicating that the larger distance mating parents had,the higher level of genetic diversity of progenies were.The order of genetic diversity of progenies of 5 mating types in Liriodendron from high to low was multi-male parent pollination progenies,inter-species progenies,backcross progenies, intra-species progenies,and self-cross progenies.The level of genetic diversity among progenies of reciprocal cross with the same parents had almost no difference.Correlation analysis showed that the correlation between phenotypic variation of progenies of different mating types in Liriodendron and genetic diversity in DNA level was not significant.