楚雄华山松种子园无性系SRAP多样性分析

Analysis on the SRAP Diversity of Pinus armandii Clones Seed Orchard in Chuxiong

【目的】明确云南楚雄华山松无性系种子园内不同种源的遗传多样性。【方法】采集种子园内6个种源的96份华山松无性系单株针叶,采用改良的CTAB法提取基因组DNA,并利用SRAP标记对其进行遗传多样性分析。【结果】筛选获得26对条带清晰、PCR反应稳定且多态性较高的SRAP引物组合。多态性位点百分率平均值为81.22%,Shannon多样性指数(I)为0.3944,Nei’s基因多样性指数(H)为0.2595,不同种源间的遗传分化系数(Gst)为0.1169;华山松种子园内各无性系在种源间变异较小,而种源内表现出较高的遗传变异;6个种源可聚为3类,遗传变异丰富度与地理距离无显著相关性(P>0.05)。【结论】楚雄华山松无性系种子园内6个种源间的遗传多样性较低,变异主要存在于各种源内。地理距离对各无性系材料的遗传距离无明显影响。在该种子园内进行杂交育种时,应以分子标记结果为主、参考地理距离进行杂交亲本的选配工作。

[Purpose]To analyze the genetic diversity among different clones in Pinus armandii seed orchard in Chuxiong City,Yunnan Province.[Methods]Genomic DNA was extracted from the tissue needles of 96 clones from six provenances of P.armandii by improved CTAB method,and genetic diversity was analyzed by SRAP markers.[Results]A total of 26 pairs of SRAP markers with clear bands,stable PCR reaction,and high polymorphism were genotyped.The average percent-age of polymorphic loci was 81.22%,Shannon’s diversity index(I)was 0.3944,Nei’s gene diversity index(H)was 0.2595,and genetic differentiation coefficient(Gst)among provenances was 0.1169.The variation among six provenances was low in the seed orchard of P.armandii,while the genetic variation within provenances had high level.Six provenances were clustered into three groups,and there was no significant correlation between genetic diversity and geographical distance(P>0.05).[Conclusion]The genetic diversity among six provenances of P.armandii is low,and the vari-ation is existed mainly in various provenances.Geographical distance has no significant effect on the genetic distance of clonal materials.The molecular markers will be used mainly,and the geographical distance will be referred in breeding of P.armandii,especially in the selection of the parents of crosses in this seed orchard.