番茄灰霉病菌对咯菌腈的抗性诱变及抗药突变体的生物学特性

Induced mutation of Botrytis cinerea resistant to fludioxonil and biological characteristics of resistant mutants

为评估番茄灰霉病菌Botrytis cinerea对咯菌腈的抗性风险,就室内经紫外照射获得抗药突变体的方法及抗性突变体的生物学性状进行了研究。结果表明:番茄灰霉病菌分生孢子的紫外照射亚致死时间为90～120 s;经亚致死时间紫外照射后,4个亲本菌株中有2个菌株共产生了6个抗咯菌腈的突变体,其EC50值是亲本菌株的310倍以上,抗性突变频率为3.13×10-7;经紫外照射诱变获得的所有抗性突变体在菌丝生长速率、产孢量、产菌核能力及其在番茄果实上的致病性方面均比其亲本菌株明显降低。相关分析显示,所得抗咯菌腈突变体对氟啶胺、啶菌唑、啶酰菌胺和嘧霉胺无交互抗性。表明番茄灰霉病菌对咯菌腈的抗药性风险较低。

To assess the resistance risk of Botrytis cinerea to fludioxonil, the method for fludioxonil resistance mutagenesis and the biological characteristics of resistant mutants were studied. The results showed that the sub-lethal UV irradiation time for the conidia of B. cinerea was 90 - 120 seconds. Four wild sensitive parental isolates were irradiated for sub-lethal time by UV, and six resistant mutants were obtained from two parental isolates. The ratio of ECs0 value of resistant mutants comparing with that of its parental strain was more than 310 times,the frequency of resistance mutation was 3.13 x 10^-7. The mycelial growth rate, sporulation, sclerotia production and pathogenicity of resistant mutants decreased significantly as compared with their parental isolates. The analysis showed that the mutants had no cross resistance to other fungicides that have different mechanisms. The above results indicated that B. cinerea on tomato had low risk of resistance to fludioxonil.