K84的生物防治效果与土壤杆菌Ti质粒类型的关系

用K84对我国不同寄主来源的68个Agrobacterium tumefaciens菌株进行生物防治试验,结果表明:K84对我国桃树菌株的防治效果显著,对新疆的啤酒花菌株也有效;但对浙江萧山的部分啤酒花菌株无效;对甜菜菌株的防治效果不佳;对葡萄菌株基本上无效。对致病菌株的质粒类型的研究结果表明:桃树、啤酒花和甜菜菌株基本上都是胭脂碱(Nopaline)型质粒、葡萄菌株基本上是章鱼碱(Octopine)型质拉。试验中还发现不少胭脂碱型菌株不能被K84所防治。此外,在甜菜和毛白杨菌株中也发现了对细菌素A84(agrocin84)敏感,但不能被K84防治的菌株。

RELATIONSHIP BETWEEN TI PLASMID TYPE OF AGROBACTERIUM TUMEFACIENS AND THEIR BIOCONTROL BY K84

Biological control experiment has been done in greenhouse with A.radiobacter strain K84 against 68 pathogenic strains of A,tumefaciens isolated from six species of host plants. The result indicated that strains from peach could be controlled effectively, K84 also gave a good result to control the strains from hop (.H.cufulus L.) of Xinjiang, but not the hop strains from Xiaoshan (Zhejiang Province). K84 failed to control the crown gall of grapevine, and biological control might breakdown when K84 was used to control the crown gall of beet. By identifying the opines synthesized in the gall on tomato seedling incited by pathogenic strains, it was found that strains from peach, apple, hop beet and Chinese White poplar harboured nopaline type Ti plasmid. Strains from grapevine harboured octo-pine Ti plasmid. The result indicated that some strains carrying a nopaline Ti plasmid are not subject to the control by K84, neither are some strains sensitive to agrocin 84.