油松天然群体遗传结构的研究

Genetic Structure of Natural Populations of Chinese Pine

本文运用同工酶电泳技术对油松大配子体的遗传结构进行了研究，分析材料为油松大配子体，共检测了４个群体４个酶系统（ＧＯＴ、ＭＤＨ、ＧＤＨ、ＡＬＰ）的１０个基因位点。结果表明，油松群体在这几个酶系统上的遗传变异水平中等偏低，４个群体多态位点百分率平均为５６．７％，等位基因平均数为１．７６，平均期望杂合度０．１５９；群体内纯合体不足，杂合体过量，大都处于非平衡状态；群体间的分化程度较低，４个群体的平均遗传距离为０．０１１；同工酶测定的总变异中，只有１％来自群体间。

Seeds from 12 natural populations of Chinese Pine (Pinus tabulaeformis Carr.) at four regions in Shaanxi Province were analyzed through the methods of horizontal polycrylamide gel electrophoresis in 10 loci of 4 enzymes (GOT, MDH, GDH and ALP). The results are: (1)there was a low isozyme genetic variation in the populations. On the average, 56.7% of the loci were polymorphic, the number of alleles per locus was 1.76, and the expected heterozygosities was 0 153; (2) the populations of Luonan, Tongchuan and Hancheng deviated from Hardy Weiberg proportions,while Taibai conformed to the law.Analysis of fixation index showed on excess of hetorozygotes relative to Hardy-Weiberg expectations; (3) only 1% of the observed genetic variation appeared among populations, the remainder was due to differences among individuals within the populations; (4) no significance relationship exists between genetic distance in the populations of Chinese Pine. Based on the results above, genetic improvement strategies for Chinese Pine are brought forward.