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通过对湖北省孝昌县小悟乡的马尾松（Ｐｈｕｓ ｍａｓｓｏｎｉａｎａ）天然林的针叶进行的同工 酶实验，６种酶系统的１１个基因位点得到了确认。以各基因位点上的等位基因的频率为基础， 对该林分内部的遗传变异进行了研究，结果表明，该林分具有较高的遗传变异性，其多态位点 百分率（ＰＩ）为９０．９％、等位基因平均数（Ｎａ）为３．１８、有效等位基因（Ｎｅ）为１．９１、平均期待杂 合率（Ｈｅ）为０．４２、近交系数（Ｆｉｓ）为０．３３，且存在不同基因位点间高频率的连锁不平衡。同时 将马尾松个体间的距离分成不同的等级，考察各等位基因频率的变化情况（Ｍｏｒａｎ’ｓＩ和ＳＮＤ 曲线的变化规律），进一步对该林分内的遗传构造和林分的成立过程进行了研究和探讨，发现 其邻域的大小为１０～１２ｍ。在此基础上提出了对该类的天然林的遗传资源保存的对策。
Through the isozyme experiments on coniferous natural forests of Phus massoniana in Xiaowu Township, Xiaochang County, Hubei Province, 11 genetic loci of 6 enzyme systems were confirmed. Based on the allele frequency of each locus, the genetic variation within the stands was studied. The results showed that the stands had higher genetic variability, and the percentage of polymorphic loci (PI) Was 90.9%, the average number of alleles (Na) was 3.18, the effective allele (Ne) was 1.91, the average expected heterozygosity (He) was 0.42, the inbred coefficient (Fis) 0.33, and there is a high frequency of linkage disequilibrium among different gene loci. At the same time, the distance between individuals of Pinus massoniana was divided into different grades to investigate the changes of the allele frequency (the change rule of Moran’sI and SND curves), and to further the establishment of genetic structure and stand in the forest The research and discussion, found that the size of its neighborhood 10 ~ 12m. Based on this, the countermeasures for conserving the genetic resources of this kind of natural forest are put forward.