中文摘要：

从浙江宁波14个樱花（Cerasus Mill.）病株样本上分离到多株土壤农杆菌菌株,其中10个菌株可致指示寄主番茄形成肿瘤,对菌株Czx-3的16S rDNA序列比对,确定樱花根癌病是由根癌土壤杆菌（Agrobacterium tumeaciens）侵染所致.进一步开展的标准生化和生理反应测试、碳源利用和选择性培养基等试验,鉴定出7个根癌病菌株为土壤农杆菌（A.tume aciens）生物型2型,占70％,为优势种群,其余3个菌株为生物型1型.对樱花根癌病菌分类地位的确定,樱花种苗的检疫和病害控制奠定了理论基础.

英文摘要：

Strains were obtained from 14 samples of crown gall on Cerasus Mill.in Ningbo,Zhejiang Province,China,10 of which could form crown gall tomato.The pathogen was identified as Agrobacterium tumefaciens based on phenotypic features of the cells and colonies,biochemical characteristics and sequence analysis of 16S rDNA.These strains were further identified based on reactions to standard biochemical and physiological tests by carbon utilization and selective media for identification.Among the 10 strains,7 were biotype 2,accounting for 70%of the total.The other 3 strains were biotype 1.The finding that A.tumefaciens could cause crown gall disease of Cerasus laid the foundation for systematic study on quarantine and disease control.