烟草赤星病菌苗期人工接种方法的研究  

Inoculating method for Alternaria alternata in seedling stage of tobacco

作　　者：沈奕[1] 高智谋[1] 杜雷[1] 王革 

机构地区：[1]安徽农业大学植物保护学院,合肥230036 [2]云南玉溪红塔集团生化研究中心,玉溪653100

出　　处：《安徽农业大学学报》2009年第3期356-359,共4页Journal of Anhui Agricultural University

基　　金：安徽省教育厅自然科学重点项目(2006KJ057A)资助

摘　　要：以红大和K326为供试烟草品种,以烟草赤星病菌强致病力菌株GY-31为供试菌株,采用菌丝块接种、孢子喷雾接种、孢子液棉球接种、孢子悬滴接种和菌丝悬滴接种等5种方法接种烟草7叶期幼苗,结果表明,孢子液棉球接种和菌丝块接种在2个烟草品种上都能引致发病,而且重复性好,适用于烟草赤星病苗期接种;孢子喷雾接种和孢子悬滴接种成功率低,菌丝悬滴接种在红大上引致叶片枯萎,在K326上未引起发病,重复性差,均不适合于烟草赤星病苗期接种。进一步研究孢子悬浮液浓度和湿度对孢子液棉球接种法接种效果的影响,结果显示,在供试孢子悬浮液浓度范围内,接种所致病叶率随着孢子悬浮液浓度的增大而提高;悬浮液浓度低于104个.mL-1,接种所致病叶率低于35%;悬浮液浓度为105～107个.mL-1,接种所致病叶率为70%～92%;接种后保湿能显著提高接种所致病叶率。Under greenhouse and potted condition,inoculating the strong pathogenic isolate GY-31 of Alternaria alternata on tobacco seedlings of the tested varieties, Hongda and K326 at 7-leaf stage was conducted by applying mycelium block inoculation, spore spraying inoculation, spore suspension tampon inoculation, spore hanging drop inoculation, mycelium hanging drop inoculation, respectively, to select and develop a suitable method for inocula- tion of the brown spot pathogen in seedling stage of tobacco. The results show that both spore suspension tampon method and mycelium block inoculation can cause brown spot on the two varieties of tobacco, suggesting that the two methods are suitable to the inoculation of A. alternata in seedling phase. However, spore spraying inoculation and spore hanging drop method had a low success rate, and mycelium hanging drop inoculation wilted the leaves of Hongda and didn＇t cause any lesion on K326, with a worse repeatability, suggesting that the these methods are not suitable to the inoculation of the pathogenic fungus. Further, the influence of conidial suspension concentration and moisture on the inoculation results of tobacco brown spot by spore suspension tampon method was investigated by two-factor randomized block design, and the results indicate that the incidence of diseased leaves caused by inoculation increased with the conidial suspension concentration. The incidence of diseased leaves was less than 35% when the conidial suspension concentration was below 104 CFU. mL^-1, while the incidence of diseased leaves was between 70% and 92% when the conidial suspension concentration ranged from 105 to 107 CFU .mL^-1. The results al-so suggest that moisturizing may improve the incidence of diseased leaves caused by inoculation.

关 键 词：烟草赤星病 接种方法 苗期 评价 

分 类 号：S435.72[农业科学—农业昆虫与害虫防治] S432.44[农业科学—植物保护]