烟草青枯病菌(Pseudomonas solanacearum)变异特性的研究

STUDIES ON THE VARIANCE OF PSEUDOMONAS SOLANACEARUM STRAINS FROM TOBACCO

本文研究了25个烟草青枯菌株脱毒后对碳水化合物利用能力和产细菌素能力的变异性。结果表明:脱毒后烟草青枯菌株对糖、醇的利用能力和产细菌素的能力发生了变异。脱毒后不同生物型和反应型菌株的相对比率与脱毒前显著不同。脱毒前生物型Ⅲ的菌株占62.5%,反应型 b 的菌株占12.5%,而脱毒后生物型Ⅲ和反应型 b 的菌株分别为54.1%和25%。生物型Ⅳ和反应型 a、c 的菌株,脱(?)后全部突变力其他的生物型或反应型的菌株。脱毒后还产生了生物型Ⅰ和其他类型的菌株。不同品种和地区菌株脱毒后的变异率不同,变异率景高的为 C_(316)菌株,最低的为 T_(208)菌株和玉溪菌株。脱毒后菌株的平均拮抗范围和对细菌素的平均敏感范围比脱毒前分别降低9%和35%。有一个菌株完全丧失了产生细前素的能力,35%的菌株完全丧失了对细菌素的敏感性。菌栋对不同品种和地区菌株的拮抗范围的变异率与其品种和地区来源密切相关。

The variance of twenty five Pseudomonas solanacearum strains from tobacco in the utilization of car- bohydrates and bacteriocin production was studied.The results showed obvions differences in the utilization of saccharides and hexose alchols and the production of bacteriocin between virulent and avirulent strains of the pathogen.62.5% and 12.5% virulent strains belonged to biotype Ⅲ and reaction type b,but 54.1% and 25.0% avirulent strains belonged to biotype Ⅲ and reaction type b,respectively.When they were changed to avirulent strains,the virulent strains of biotype Ⅳand reaction type a,c were all changed to oth- er types.BiotypeⅠwhich was not found in virulent strains was observed in avirulent strains.The variance rates of the strains from different varieties and location were different.The variance rate of strains from variety K316 was the highest,that from variety 7208 and Yuxi county was lowest.After the strains lost the pathogenicity their average antagonistic range and sensitive range to bacteriocin were decreased about 9% and 35%,respectively among them one lost bacteriocin-producing ability and 36% ones lost the sensitivity to bacteriocin completely.The variance rates of antagonistic range of different strains to those from differ- ent varieties and locations were related to the varieties and locations from which they were isolated.