土壤杆菌K1026对樱桃冠瘿病病原菌的抑制作用及田间防治效果

摘要

Crown gall,caused by pathogenic Agrobacterium spp.,is a serious problem in the production of cherry.Agrobacterium rhizogenes strain K1026 was introduced from Australia,and has shown a high efficiency in biocontrol of crown gall disease.This research verified the control action of K1026 against two different species (biovars) of crown gall pathogens by three different methods:double layer inhibition test on agar medium,carrot root disc bioassay and tomato stem inoculation.In addition,this study reported the effect of different K1026 inoculation times on tumour formation by pathogenic strains in the carrot disc bioassay.The results showed that K1026 could inhibit the generation of tumor tissues on carrot discs when inoculated up to 24 h after addition of the pathogen.The mechanisms of action of K1026 included the production of agrocin antibiotics (agrocin 84 and agrocin 434) and competition for adsorption and infection sites on the plant tissue.In field trials,strain K1026 demonstrated a mean inhibition of crown gall disease of cherry rootstock'Chinese Cherry'of up to 81.61％,and the incidence of crown gall disease dropped substantially to 18.13％.These results suggest that A.rhizogenes K1026 can be used for biocontrol of cherry crown gall disease in the field in China.%由致病性根癌土壤杆菌Agrobacterium spp.侵染引起的根癌病对樱桃等果树生产造成严重的影响.利用双 层平板、胡萝卜圆盘法和接种指示植物番茄等方法验证了澳洲生防菌株K1026对2种不同原生物型樱桃冠瘿病病原菌的抑制作用;检测了不同接种时间对病原菌侵染产生瘤状组织的影响,结果显示提前或者在病原菌接种后20 h内接种K1026可抑制胡萝卜产生瘤状组织;研究了K1026对大樱桃根癌病的作用机制是产生土壤杆菌素和竞争附着位点;田间试验表明K1026蘸根处理,对‘中国樱桃’株系冠瘿病的防治效果达81.61％,使发病率降低至18.13％.