【摘要】 保持林木育种群体较高的遗传多样性是对林木进一步选择和改良的前提 ,而评价育种系统中遗传多样性变化的工作则很少 .该文以一油松育种系统中 6个群体为研究对象 ,借助水平淀粉凝胶电泳的同工酶分析方法 ,用筛选出的ACP ,ADH ,GOT ,CAT ,MDH ,PGM ,SKD ,MNR ,LAP共 9种酶系统 15个位点 ,分析了各群体间和群体内的遗传多样性状况 .研究结果表明 :①各群体内均有较高的遗传多样性水平 ;②种子园无性系群体的遗传多样性水平高于天然林 ;③种子园不同时期产生的两个自由授粉子代群体的遗传多样性与天然林子代群体相似 ;④遗传多样性参数在P0 到F2 三个世代间表现出递增趋势 ,说明改良群体可以维持较高的遗传多样性水平 ;⑤ 3个亲代群体的多数位点遵循Hardy Weinberg平衡 ,而 3个子代群体则与之相反 .该文对油松改良过程群体的遗传多样性变化及影响因素作了讨论 ,分析了群体是否遵循Hardy Weinberg平衡的原因 ,探讨了如何维持和提高种子园遗传多样性和遗传效率 ,提出了进一步研究的建议 .更多还原

【Abstract】 Keeping higher genetic diversity within breeding population of forest tree is the premise for future selection and improvement. On the analysis of 9 isozymes, ACP, ADH, GOT, CAT, MDH, PGM, SKD, MNR and LAP, by horizontal starch gel electrophoresis, the changes of genetic diversity parameters among 6 populations, parental (NS) and progeny(NSP) of natural stands, parental (SO) and later progeny (SOP) of seed orchard and parental (TP) and progeny (TPP) of early testing populations, within a Chinese pine ( Pinus tabulaeformis Carr.) breeding system in Liaoning Province were detected. The results show that: ①There is higher genetic diversity within each population but less differentiation among them.②The genetic diversity of SO, which built by plus trees from 20 natural stands, is higher than NS. ③The diversity parameters of SOP are similar with NSP. ④The parameters of genetic diversity are increased from parental population(SO) to its first generation (TP) and second generation (TTP), and the parameters of all the three populations are higher than NS. It seems that the improving process could keep higher genetic diversity. ⑤The 3 parental populations (NS, TP and SO) are in Hardy Weinberg equilibrium, but 3 progeny populations (NSP, TPP and SOP) are not in accordance with Hardy Weinberg equilibrium. The strategies of conservation of genetic diversity within forest tree breeding system were discussed as well.更多还原