楸树优良种质资源的AFLP遗传多样性分析

Genetic diversity analysis of Catalpa bungee germplasm with AFLP markers

为研究44份楸树种质资源的遗传多样性及亲缘关系,利用AFLP分子标记技术,对采自鲁豫地区的44份楸树优良种质进行了分析。结果表明:筛选出的8对PstI/MseI引物组合从44份楸树种质中共扩增出1087条清晰条带,其中多态性条带(NPB)1043条,多态性比率(PPB)达到95.60%。平均每对引物可扩增出135.88条带和130.38条多态性带。每个位点的平均有效等位基因数(Ne)、Nei’s平均基因多样性(H)、Shannon平均信息指数(Ⅰ)分别为1.3210、0.2003和0.3204,且8对引物组合共产生261条特异性条带,表明楸树资源间具有丰富的遗传多样性。通过计算种质间遗传相似系数和进行UPGMA聚类分析得出,各种质材料间的遗传相似性系数在0.5022~0.7919间,平均为0.6527。以遗传相似性系数0.65为界44份楸树种质可划分为5组,其中第1组包括15个山东种质和2个河南种质;第2组包括18个山东种质和3个河南种质;第3组包括3河南种质;第4组包括1个河南种质;第5组包括2个河南种质。这表明不同地理生态条件造就了各种质材料间丰富的遗传多样性,其遗传多样性以及亲缘关系与其地理分布并不完全一致。综上,AFLP标记技术能较好的揭示楸树种质资源的遗传多样性和亲缘关系,可为楸树优良种质资源的收集、鉴别及利用提供参考依据。

In order to study the genetic diversity and relationship of Catalpa bungee from Shandong and Henan Province, genetic diversities of 44 C. bungee advanced germplasm resources were tested by AFLP. The results showed that among 1 087 bands detected amplified by the selected 8 pairs of PstI/MseI primer, 1 043 (95.60%) were polymorphic from 44 C. bungee advanced germplasm resources. On average, each pair of primers amplified 135.88 bands and 130.38 polymorphic bands, and 8 pairs of primer produced 261 specific bands. The number of effective alleles Ne was 1.321 0, Nei’s gene diversity H was 0.200 3, and Shannon’s information index Ⅰ was 0.320 4. The average genetic similarity coefficients ranged from 0.502 2 to 0.791 9 with an average of 0.652 7. According to the genetic similarity of 0.65, the samples were divided into 5 groups by UPGMA clustering analysis. Group Ⅰ includes 15 germplasm collected from Shandong Province and 2 germplasm collected from Henan province;group Ⅱ includes 18 germplasm from Shandong and 3 germplasm from Henan;group Ⅲ includes 3 germplasm from Henan;group Ⅳ includes germplasm from Henan;Group 5 includes 2 germplasm from Henan.The results show that different geographical and ecological conditions have produced rich genetic diversity among various materials. However, their genetic diversity and genetic relationship are not completely consistent with its geographical distribution. In summary, AFLP can better reveal the genetic diversity and relationship of germplasm resources for C. bungee. The results can provide references for collection, identification and utilization of germplasm resources for C. bungee.