Mating Patterns And Gene Flow In An Experimental Population Of Liriodendron Revealed By SSR Markers

The 220 open-pollination progenies from 4 maternal trees and its parents in an experimental population of Liriodendron were analyzed paternity using 12 SSR primers. The mating patterns and distances of effective pollen dispersal and offspring genetic diversity of Liriodendron were studied by paternity analysis, and this paper explored introgressive hybridzation between L. chinense Sarg.and L. tulipifera Linn. The results were as follows:1. The number of alleles per locus was from 3 to 8, and the total polymorphic alleles in 12 loci was 64 which per locus had 5.33 alleles on average. The CERVUS software could assign the real paternity for its 138 progenies with 95% CL. The cumulative exclusion probability of 12 SSR loci was 98.46%.2. The mating patterns of Liriodendron were multiform such as selling and intraspecies mating and interspecies mating in the condition of open-pollination. The selfing rate of L. chinense Sarg.(HS and LS) were 5% and 11.6%, respectively, while the selfing rate of L. tuIipifera Linn. was zero. It seems that intraspecies mating occurred more frequently than interspecies mating in Liriodendron.3. An obvious variation of male reproductive success was found among individuals, and the highest and the lowest male reproductive success were 10.9% and 0, average is 1.28%. Liriodendron had bidirectional sexual selection as female, LS parent of L. chinense Sarg. and BM parent of L. tulipifera Linn. were easy to accept intraspecies pollen. At the same time, male parents of L. tulipifera Linn. had distinct sexual selection with female parents L. tulipifera Linn.,too.4. The average effective pollen dispersal distance of Liriodendron ranged from 15m to 35m, with the maximum dispersal distance of 77m.5. The mean Shannon's Information index(â… ) of offspring population in the Liriodendron. was 1.1487. The genetic diversity of offspring Families came from L. tulipifera Linn. were higher than offspring Families of L. chinense Sarg. The coefficient of genetic differentiation was 0.3352 on average and the majority of genetic variation occurred within Families.6. 12 SSR primers could detect 30 special loci of L. tulipifera Linn. within 12 introgression offspring came from female parent of L. chinense Sarg, and range from 3 to 10 with per offspring had 6.6 special loci on average. While 12 SSR primers could detect 31 special loci of L. chinense Sarg., and per offspring came from female parent of L. tulipifera Linn.had 6.6 special loci on average. Thus, in certain extent, it can saw that the level of introgressive hybridzation with L. chinense Sarg. to its offspring was slightly higher than L. tulipifera Linn.