继代对棉花黄萎病落叶型菌系致病力的影响

Effect of Documenttation to Pathogenicity of Defoliated Cotton Verticillium wilt Strains

在棉花黄萎病菌致病力分化的研究中,我们发现落叶型菌系T9的致病力有日渐减弱的倾向,不少单位也遇到此类问题,为明确落叶型菌系是否会在继代过程中致病力发生变化,如何变化等问题,我们采用国内外典型的3个落叶型菌系T9和V991、V76,以及2个非落叶型菌系V146和V250为研究对象,采用连续转接的方法,利用3个不同抗病性品种对它们的致病力进行测定,以明确经过连续转接后这些菌系的致病力是如何变化的。结果表明,经过14代的转接,落叶型菌系T9的致病力发生了显著\降,甚至已失去其致使棉花落叶的能力,即连续转接后,落叶型菌系T9已变成非落叶型菌系,且其致病力有成为弱致病力菌系倾向;但我国落叶型菌系代表V991则仍然保持其强致病力的落叶菌系特性。

During the cotton Verticillium wilt pathogenicity studied.We found that the pathogenicity of defoliated strain T9 was weakening,and many units met the some problems.Are the pathogenicity vary during the subculture? We select 3 defoliated strains T9, V991 and V76,and 2 no-defoliated strains V146 and V250 for studied.Using continued subculture for 14 times.Then detected pathogenicity of different stain subculture times.The result showed that after subculture for 14 times,pathogenicity of defoliated strain T9 was decrease significant.And loss the defoliated ability,defoliated strain T9 had changed to no-defoliated strain,pathogenicity had changed to weaked pathogenicity strain.But domestic defoliated strain V991 did not any change during the subculture,keep the feature of defoliated strain.