Study On Dynamic Dispersal Of Pollen And Selective Impregnation In Pinus Tabulaeformis Seed Orchard

This study using microsatellite markers to execute Paternity analysis for open-pollinated and control-pollinated seeds of a Seed Orchard in Pinus tabulaeformis, discussing the relations between dispersal distance of pollen and composing of final generation under open-pollinated situation as well as questing for the influence of pollen index on offspring structure under control-pollinated situation, sequentially guiding the building of high generation seed orchard and providing gist to draw reasonable breeding plant. The main results were as follows:1) Paternity analysis for 281 seeds showed that 126(about 44.5%) seeds could found the pollen donor at 80% confidence level.2) Paternity analysis for opened-pollination seeds showed that the maximal dispersal distance of pollen is 85m, and the effective dispersal distance is 30m. Pollen that fertili -zed most of the offspring on the maternal tree was derived from a relatively small number of paternal trees. Paternity analysis showed that there are 35 and 27 paternal trees did not fertilize any offspring on the maternal trees of clone 11# and 24#.3) Paternity analysis for opened-pollination seeds indicated that maternal trees not received pollen selectively. Paternity analysis for controlled pollination seeds showed that the donors of pollen were extensive, there were 15 and 13 clones fertilized offspring on maternal trees of clone11# and clone 24#respectively. In controlled pollination experimentation, there was a conspicuous tendency for pollen from a small number of trees to fertilize the offspring too, i.e. 4 individuals viz.50#,7#,25#,33# fertilized 50.62%and 61.54%of the offspring on maternal tree clone11# and clone 24#respectively, certainly, the reason should farther study.4) This study not found the size of microspore influence on the fertilization. The disper -sal distance or pollination success was not restricted by pollen viability, donor whose pollen viability was lower than the average also had the probability of fertilizing offspr -ing on maternal trees. For example the pollen viability of clone 6#,39#,13#,11#,8#,38#,30#,36#,14# was lower than average pollen viability, but they fertilized 16 seeds(at 80% level).5) Pollen contamination from the surrounding stands was observed during the paternity analysis.4 alleles from 5 different SSR loci were revealed only existing in the 12 progen -ies. The contamination ratio of pollen was up to 7.45%.6) It was observed that about 2%~4% of the progenies were empty seeds and monster seedings which were probably caused by self-pollination of the maternal trees.