陕西省苹果黑星病菌遗传多样性的AFLP分析

Genentic diversity of Venturia inaequalis of Shaanxi province with AFLP analysis

【目的】明确陕西省苹果黑星病菌的遗传多样性,为苹果抗病育种和黑星病菌的综合防治提供理论依据。【方法】利用25对AFLP引物,对采自陕西兴平、旬邑的46个苹果黑星病菌菌株进行群体结构和遗传多样性分析。【结果】25对AFLP引物共扩增出421个条带,其中多态性条带326个,占总带数的77.4%;陕西兴平和旬邑苹果黑星病菌AFLP多态位点比率为22.57%～69.83%,平均为47.74%;等位基因观测数为1.23～1.70,平均为1.48;有效等位基因数为1.16～1.46,平均为1.33;Nei氏基因多样性指数为0.09～0.27,平均为0.19;Shannon信息指数为0.14～0.39,平均为0.27;各类群间的Nei氏遗传相似系数为0.8151～0.9487,遗传距离为0.0527～0.2044;总的遗传多样性为0.29,群体内遗传多样性为0.18,群体间遗传多样性为0.11,遗传分化系数为0.38;陕西苹果黑星病菌菌株分为2大类,分离自旬邑嘎啦、兴平嘎啦、旬邑富士的菌株聚为一类,分离自旬邑红星、兴平红星、旬邑秦冠、兴平秦冠的菌株聚为另一类。【结论】陕西苹果黑星病菌菌株的遗传多样性与地理来源没有明显的相关性,而与寄主品种具有一定相关性。

[Objective] The study was to demonstrate genetic diversity of Venturia inaequalis in Shaanxi,and to provide the basis for disease-resistant breeding and integrated control of apple scab.[Method] The genetic diversity and colony formation were analyzed for forty-six strains of V.inaequalis from apple field by combination of 25 pairs of primers using AFLP technology in Xingping and Xunyi.[Result] The results showed that 421 bands were amplified,of which 326 bands were polymorphic,the rate of polymorphic bands was 77.4%.The rate of AFLP polymorphic sites was 22.57%-69.83% in V.inaequalis between Xingping and Xunyi and the value of average was 47.74%;the number of alleles per locus was 1.23-1.70,and the average number of alleles 1.48;the effective number of alleles was 1.16-1.46,and the average number of alleles 1.33;the Nei＇s gene diversity was 0.09-0.27,and the average 0.19;Shannon＇s information index was 0.14-0.39,and the average 0.27;the index of genetic similarity of different groups was 0.815 1-0.948 7,the genetic distance 0.052 7-0.204 4;the total genetic diversity was 0.29,the varitations within collections 0.18,the varivations among the collections 0.11,the index of genetic varivations 0.38.Based on the data of AFLP analysis,the apple scab strains can be classified into two categories.Xunyi Gala,Xingping Gala and Xunyi Fuji were clustered together;Xunyi Red Star,Xingping Red Star,Xunyi Qinguan and Xingping Qinguan were clustered.[Conclusion] The genetic diversity was not correlated in different geography in V.inaequalis in Shaanxi,but there were differences in different hosts.