摘要
采集、分离获得江苏省通州市4乡镇油菜菌核病菌(Sclerotiniasclerotiorum)的223个菌株,对多菌灵(MBC)和乙霉威(NPC)的敏感性测定得到2种表型,其中143个菌株为MBCSNPCHR,其余80个菌株为MBCHRNPCS,后者对温度7～28℃不敏感。苯并咪唑类杀菌剂通过与抗药性相关的β-微管蛋白结合,抑制细胞的有丝分裂。克隆S.sclerotiorum6个菌株的β-微管蛋白基因,获得大小为874个碱基、编码273个氨基酸的基因片段,与典型模式菌粗糙脉孢霉(Neurosporacrassa)进行序列比较发现具高度同源性。研究证明S.sclerotiorum的β-微管蛋白198位氨基酸由谷氨酸(Glu)突变为丙氨酸(Ala),是导致油菜菌核病病原菌产生对多菌灵抗药性的主要原因;突变位点和突变类型与其他抗多菌灵真菌一致,与乙霉威之间存在明显负交互抗性。
223 Scletotinia sclerotiorum strains were isolated from Tongzhou of Jiangsu Province. Two phenotypes were identified when tested for sensitivity to carbendazim (MBC) and diethofencarb (NPC). 143 isolates showed phenotype of carbendazin-sensitivity and diethofencarb-highly-resistance (MBCSNPCHR) and other 80 isolates showed carbendazim-highly-resistance and diethofencarb-sensitivity (MBCHRHPCS). The latter was not sensitive to temperature variation between 7～28℃. β-tubulin genes from 6 strains of carbenzim-resistant S.sclerotiorum were cloned and compared the gene nucleotide sequences (874bp) and their deduced amino acid sequences (273 amino acid) with those of the genes of typical carbenzim-resistant fungus, Neurospora crassa. The partial nucleotide sequence of β-tubulin and deduced amino acid of S.sclerotiorum were highly homologous to those from N.crassa. Sequence comparison between MBCS and MBCHR isolates of S.sclerotiorum revealed a single point mutation leading to change at amino acid position 198 from glutamic to alanine acid. This mutation was the same as those identified in benomyl-resistant field isolates of other phytopathogenic fungi, and there existed obvious negative cross-resistance between carbenzim and diethofencarb.
出处
《中国油料作物学报》
CAS
CSCD
北大核心
2003年第2期56-60,共5页
Chinese Journal of Oil Crop Sciences
基金
国家"863"计划(2001AA249041)
国家自然科学基金(30070510)
