滇杨优树遗传多样性的AFLP分析

Analysis of Genetic Background of 52 Populus yunnanensis Superior Trees by AFLP Markers

以收集于云南和四川的52株滇杨优树为试验材料,并以1株大叶杨、1株北京杨和2株黑杨做类外对照,采用AFLP分子标记技术进行基因组DNA水平检测。结果表明,筛选出的8对EcoRⅠ+3/MseⅠ+3引物组合对52株滇杨优树共扩增出264条带,其中多态性条带174条,多态带百分率为64.52%,检测到有效等位基因数(Ne)为1.184,基因多样度(H)为0.121,Shannon信息指数为0.201,平均遗传相似系数为0.877;对56份杨树样本共扩增出325条带,其中多态性条带共247条,多态带百分率为75.21%,检测出有效等位基因数(Ne)为1.185,基因多样度(H)为0.122,Shannon信息指数为0.209,平均遗传相似系数为0.876。UPGMA聚类分析结果显示,除滇杨优树QXB007与QXJ030外,其余杨树分析样本均能够被鉴别。基于采集地和遗传相似系数的模糊聚类分析表明,52株滇杨优树除开远采集地外,丽江采集地样本与其他采集地样本之间均有交集,说明丽江可能是滇杨的分布中心和起源中心。该研究结果为滇杨人工选择育种、遗传改良、种质资源收集与保存等提供了理论依据。

In order to deeply understand the genetic background of Populus yunnanensis superior trees, AFLP was employed to analyze 52 P. yunnanensis superior trees and their outgroup control, P. lasiocarpa, P. beijingensis and P. nigra from Sichuan and Yunnan provinces at genomic DNA level. From 52 P. yunnanensis superior trees, totally 247 AFLP fragments were obtained by 8 pairs of selected EcoR I ＋ 3/Mse I ＋3 primer combinations, in which 174 were polymorphic and the average percentage of polymorphic bands was 64.52%, and the values of effective number of alleles （Ne）, Nei＇s gene diversity （H） and Shannon＇s information index （I） were 1. 184, 0. 121 and 0. 201, respectively. Totally 325 AFLP fragments were obtained by the 8 prime combinations from 56 poplar samples, in which 247 bands were polymorphic and the average percentage of polymorphic bands was 75.21 %, and the values of effective number of alleles （Ne）, Nei＇s gene diversity （H） and Shannon＇s information index （I） were 1. 185, 0. 122 and 0. 209, respectively. UPGMA cluster results showed that 54 poplar samples were distinguished from each other except QXB007 and QXJ030. Based on collection site and genetic similarity coefficient, fuzzy cluster results showed that the samples collected from Lijiang had intersections with samples collected from othersites except Kaiyuan. It revealed that Lijiang may be the distribution and origin center of P. yunnanensis. The results were very helpful to the artificial selection breeding, genetic improvement and collection and preservation of germplasm resources of P. yunnanensis.