杭州地区番茄苗期猝倒病的8种腐霉的DNA多态性

从28种随机引物中筛选出25种对腐霉属的10株计8种腐霉进行RAPD分析，发现腐霉属的DNA多态性是非常丰富的和普遍存在的，初步计算了10株计8种腐霉的Nei氏遗传距离，利用类平均法得到UPGMA系统树，并对它们的亲缘关系从DNA分子水平上进行了初步分析.结果表明：在这8种腐霉中，P.kunmingense与P.irregulare亲缘关系最近；P.aphanidermatum与P.tardicrescens的亲缘关系最近；P.ultimum与P.debaryanum的亲缘关系最近；P.debaryanum与P.dissotocum的亲缘关系最近.UPGMA的系统树表明这8种腐霉明显分成三大类，P.kunmingense，P.irregulare与P.spinosum聚成一类；P.aphanidermatum与P.tardicrescens聚成一类；P.ultimum，P.debaryanum与P.dissotocum聚成一类.该结果与形态分类基本相符合.

DNA polymorphism of Pythium eight species of causing tomato seedlings damping-off disease in Hangzhou region.

Twenty five random primers screened from 28 were ultilized for Random Amplified Polymorphic DNA (RAPD) analysis of 10 isolates covered 8 species of Pythium . The result showed that DNA polymorphism of Pythium was abundant. The Nei's genetic distance of 10 isolates of Pythium was initially calculated. It was used to generate unweighted pair group method using arithmetic averages (UPGMA) dendrogram to show genetic relationship among the ten isolates in 8 species of Pythium . The results showed that the nearest genetic relationship were between P. kunmingense and P. irregulare , between P. aphanidermatum and P. tardicrescens , and between P. ultimum and P. debaryanum . The UPGMA dendrogram showed the eight species of Pythium were classified into three groups. The first group was P. kunmingense , P. irregulare and P. spinosum , the second group was P. aphanidermatum and P. tardicrescens , and the third group was P. ultimum, P. dissotocum and P. debaryanum.