采用AFLP (amplified fragment length polymorphism,AFLP)分子标记技术,对5个云南松纯林居群中选取的直干型和扭曲型共计149份植株样本进行分析.结果表明,4对AFLP引物共获得多态性条带数77条,多态带百分率为90.59%.丽江白汉场、大理云龙和楚雄永仁3个居群内直干型云南松的遗传多样性高于扭曲型,而大理剑川和禄劝屏山居群内2种干形的云南松则相反,表明不同干形云南松的遗传多样性水平与干形种类无明显的相关性.云南松2种干形植株在每个居群内均具有较高的遗传分化系数(0.42~0.67)和较弱的基因交流(0.24~0.69).AMOVA (analysis of molecular variance,AMOVA)分析结果也显示每个居群内不同干形植株间的变异占了总变异的50%以上(53.67%~72.30%),表明2种云南松干形间的遗传差异是总变异的主要来源.PCoA (principal coordinates analysis,PCoA)、UPGMA (unweighted pair-group method with arithmeticmeans,UPGMA)和Bayesian聚类结果均能将直干型和扭曲型云南松进行区分,表明云南松干形变异受较强的遗传控制.该研究结果为进一步阐明云南松干形扭曲的遗传机制奠定了基础.
AFLP Analysis on Genetic Variation of Stem Forms in Pinus yunnanensis
A total of 149 specimens from 5 populations, including twist and straight stem forms, were analyzed using amplified fragment length polymorphism (AFLP) marker.As a result, 77 polymorphic loci were obtained from 4 pairs of AFLP primers, and its percentage was 90.59%.The genetic diversity ofP.yunnanensis with twist stem form were higher than that with straight stem form in Baihanchang of Lijiang, Yunlong of Dali and Yongren of Chuxiong populations, and this was opposite in Jianchuan of Dali and Pinshan of Luquan populations, which indicated no clear correlation between genetic diversity and stem form.Furthermore, P.yunnanensis with various stem forms were found holding high genetic differentiation (0.42~0.67) and low gene flow 0.24~0.69).From analysis o fmolecular variance (AMOVA), more than 50 % (53.67%~72.30%) of genetic variance were attributed to the divergence between stem forms in each population, which suggested that it was the main source of all differences.P.yunnanensis with different stem forms were divided into different groups using principal coordinates analysis (PCoA), unweighted pair-group method with arithmetic means (UPGMA) and Bayesian methods, supporting a twist stem form generated under powerful genetic control.The results of this study laid the foundation for further exploring the genetic mechanism of how twist stem form generated in P.yunnanensis.