云南稻瘟病菌抗药性研究

1981—1987年作者进行了稻瘟病菌Pyricularia oryzae抗药性研究。结果表明:玉溪、蒙自草坝、西双版纳良种场等地的稻瘟菌,对EBP、IBP已明显产生抗药性。并证实扰EBP的稻瘟菌,对IBP、EDDP、FuJi-1也有交互抗性。从而提出必须尽快控制抗性的发展。建议防治叶瘟可在IBP、EDDP、Fuji-1中任选1种,如用IBP,就避免用Fuji-1,防治穗颈瘟,宜用Tricyclazole,且每年限用1—2次。另外,在室内还用EBP诱导抗性菌成功。且发现室内获得的抗性菌,在田间接种后,抗性会有不同程度的下降缓解。相反,田间分离到的抗性菌,接种后抗性表现较稳定,下降缓解不显著。当换用杀菌机制不同的Tricyclazole进行防治,抗性菌接种区仍能取得较好的防治效果.

STUDIES ON THE FUNGICIDE RESISTANCE OF PYRICULARIA ORYZAE FROM YUNNAN PROVINCE

Some investigations were made on fungicide resistance of the Pyricularia oryzae during 1981-1985.It was confirmed that at the seed multiplication farms of Yuxi,Caoba in Mengzi and Xishuangbanna this pathogen has evidently become fungicide resistant to EBP and IBP even the EBP resistant isolates showed cross-resistance to IBP, EDDP and FuJi-one.Hence the author suggest that either IBP, EDDP or FuJi-one must be alternatively chosen for the control of leaf blast.If IBP is applied the FuJi-one can not be used.To preventing spike-neck blast Tricyclazole is avialable for at most one or two times per year.In addition, an experiment of inducing the resistance of Pyricularia oryzae by EBP has been successfuly done in laboratory.Results indicated that the resistance of Pyricularia oryzae acquired in laboratory could not keep the same level in fields as it did indoors.It reduced to some extent.On the contrary, the resistance of Pyricularia oryzae strains isolated from fields was more stable.When several forms of Tricyclazole with different mechanisms were applied for the control of resistant Pyricularia oryzae, good control effects were achieved.