草莓灰霉病菌对速克灵的抗性研究

Study on the Resistance of Botrytis cinerea in Strawberry gray mold to Procymidone

速克灵对草莓灰霉病具有很好的防治效果,但长期、单一使用很容易使草莓灰霉病菌产生抗药性。为合理使用这类杀菌剂,延缓或防止抗药性的产生,笔者通过UV-C诱变草莓灰霉病菌敏感菌株CF1获得了对速克灵具有高抗性的突变株CF1-1和CF1-2,并对抗性突变株的生长量、产孢量和致病力进行了研究,结果表明:CF1-1与CF1-2对速克灵抗性程度高,抗性水平与敏感菌株相比分别增加了484.6倍和911.0倍。抗性菌株在无速克灵的培养基上菌丝生长较敏感菌株弱,产孢量也明显少于敏感菌株;但其引起草莓离体叶片发病较敏感菌株重,病斑大且边缘颜色深;薄片黄瓜测定结果也表明,在无速克灵的情况下,敏感菌株CF1引起发病较重;而在有药条件下CF1受到一定抑制,但抗性菌株仍能致黄瓜片发病。将抗性菌株连续培养7代后对速克灵的抗性仍是相对稳定的。

The resistance of Botrytis cinerea to procymidone is easy to result from repeated and simple use, although procymidone has good control effect on gray mold of strawberry. The high-resistant strains, CF1-1 and CF1-2, were obtained by inducing sensitive strain CF1 of Botrytis cirterea with UV-C, the diameter of colony, quantums of spore-production, and pathogenicity of the two mutants were also tested for reasonable application of the fungicide to retard or avoid resistance occurring. The results showed that CF1-1 and CF1-2 had the high resistance to procymidone; the Ec50 value was 484.6 times and 911.0 times more than that of CF1. respectively. The mycelial growth rate of resistant strains on the medium without procymidone was less than that of sensitive strains and the quantums of spore-production was also less. But the leaf lesion areas of strawberry in vitro caused by CF1-1 and CF1-2 was larger, and the edge has a dark color. The result of dealing sheets of cucumber with the strains also showed that the pathogenicity of CF1was inhibited, while the two resistant strains still can cause sheets of cucumber dealed with procymidone rot; but the pathogenicity of CF1 was stronger than that of the resitant strains without procymidone. Continuous incubition for senven generations showed that the resistant inheritance of the resistant strains to procymidone was relatively stable.