烟草疫霉的产孢和接种方法研究

Research on the methods of producing zoosporangia and inoculation of Phytophthora parasitica var.nicotianae

烟草疫霉是重要的病原真菌,但在人工培养条件下难以培养、产孢以及释放游动孢子。作者对烟草疫霉培养、产孢、接种方法进行了研究。芝麻培养基、黑麦培养基、燕麦培养基可用来培养烟草疫霉,烟草疫霉在三种培养基上平均每天生长量为1.10、0.78、0.86cm;芝麻培养基、黑麦培养基为烟草疫霉产孢子囊较好的培养基,产孢能力强,分别为2.52×10~4、2.07×10~4个孢子囊/cm^2。而且孢子囊释放率高,分别为43.0%、32.1%。游动孢子囊悬浮液灌根接种和注射接种都能使烟草发病,但不同的接种方法和接种浓度下,病情指数不同。

Phytophthora parasitica var.nicotianae is an important pathogenic fungus,but it is difficult to cul- ture and produce zoosporangia on medium.Through experiments,the sesame agar medium,rye agar medium and oat agar medium can be used to culture Phytophthora parasitica var.nicotianae.Their growth speeds were 1.10,0.78 and 0.86 cm per day respectively.The sesame agar and rye agar can be used to produce zoospor- angia and their outputs of zoosporangia were 2.52×10~4,2.07×10~4 zoosporangia/cm^2 respectively,and their Release rates were 43.0% and 32.1% respectively.Tobaccos were inoculated by pouring and injecting differ- ent concentration zoospores suspension,disease indexes were directly related to the concentration and inocula- tion method.