【摘要】 为了明确烟草疫霉抗双炔酰菌胺突变株的生物学特性、抗药性遗传稳定性及突变株的致病性，以烟草疫霉菌株YCHJ为供试菌株，采用紫外线诱导的方法获得烟草疫霉抗双炔酰菌胺突变株；通过菌落形态、菌丝生长速率、游动孢子囊产生量及形态、游动孢子萌发能力等特征比较突变株与亲本菌株的生物学特性；采用菌丝生长速率法和温室盆栽试验分别检测了突变株的遗传稳定性和致病性。结果显示，菌丝块紫外诱导获得的3株突变株YCHJ2-12、YCHJ5-7和YCHJ5-16对双炔酰菌胺的抗性水平分别是62.99、47.06和10.11。游动孢子紫外诱导获得的2株突变菌株YCHJZ2-2和YCHJZ4-13的抗性水平分别是54.79和17.75。生物学特性研究结果显示，突变株和亲本菌株在菌丝形态及游动孢子囊形态上无明显差异，但在菌丝生长速率、孢子囊大小及乳突高度等方面存在差异。突变株YCHJ2-12和YCHJZ2-2菌丝的平均生长速率显著高于亲本菌株YCHJ；突变株YCHJZ4-13产生的游动孢子囊长度、宽度及乳突高度均显著高于亲本菌株YCHJ。此外，突变株YCHJZ4-13、YCHJ5-16和YCHJZ2-2的游动孢子囊产生量显著高于亲本菌株YCHJ，但突变株的游动孢子萌发率及致病性比亲本菌株YCHJ低。菌株YCHJZ4-13和YCHJ5-16的抗药性不能稳定遗传，其他菌株的抗药性随着继代培养时间的延长呈下降趋势。综上所述，烟草疫霉对双炔酰菌胺的抗性风险为低到中等。更多还原

【Abstract】 In order to clarify the biological characteristics,genetic stability of drug resistance,and pathogenicity of mandipropamidresistant strains of Phytophthora nicotianae,the P. nicotianae strain YCHJ was used as the tested strain. Mandipropamid-resistant strains of P. nicotianae were obtained by UV-irradiating. The biological characteristics of mutant strains were compared with those of their parent strain such as colony morphology,hyphal growth rate,zoosporangia morphology and production,and germination ability of zoospores. The genetic stability and pathogenicity of the mutant strains were assessed by the mycelial growth rate method and greenhouse pot trials,respectively. The results showed that the resistance levels of the mutant strains YCHJ2-12,YCHJ5-7 and YCHJ5-16 induced by mycelial UV-irradiating were 62.99,47.06 and 10.11,respectively. The resistance levels of the mutant strains YCHJZ2-2 and YCHJZ4-13 induced by UV-irradiating of zoospores were 54.79 and 17.75,respectively. The results of biological characteristics showed that there was no significant difference in hyphal morphology and zoosporangia morphology between the mutant strains and the parent strain,but there were differences in the mycelial growth rate,the size of zoosporangia and the height of papillae.The average mycelial growth rate of YCHJ2-12 and YCHJZ2-2 was significantly higher than that of the parental strain YCHJ. The length,width and papillae height of the zoosporangia produced by YCHJZ4-13 were significantly higher than those of YCHJ. In addition,the zoosporangia production of YCHJZ4-13,YCHJ5-16 and YCHJZ2-2 was significantly higher than that of YCHJ,but the germination rate of zoospores and pathogenicity of the mutant strains were lower than those of YCHJ. The resistance of YCHJZ4-13 and YCHJ5-16 to mandipropamid couldn’t be stably inherited,and the resistance of other strains decreased with the increase of cultivation generations. Based on these,it was speculated that the resistance risk of P. nicotianae to mandipropamid was low to moderate.更多还原