In order to clarify the pathogen species of soft rot of Phalaenopsis in Zhejiang Province and the difference in disease resistance of different Phalaenopsis varieties,the pathogen of Phalaenopsis soft rot was isolated and identified by the morphology,physiological and biochemical characteristics of bacteria and phylogenetic analysis.The resistance of different Phalaenopsis varieties to soft rot was evaluated by in vitro leaf inoculation method.The results showed that:1)The pathogenic of Phalaenopsis soft rot were Gram-negative bacteria.The colonies were milky white round or nearly round on nutrient agar(NA)medium(without glucose),and the colonies were light purple on nutrient glycerol manganese(NGM)medium.The single bacterium was observed to be rod-shaped.2)Based on 16S rRNA,dnaX,gapA and recA genes,a multi-gene phylogenetic tree was constructed,and the analysis showed that strain B belongs to the same branch as Dickeya fangzhongdai B16.3)The resistance of 40 Phalaenopsis varieties to soft rot in vitro was evaluated.It was discovered that there are 1 high resistant variety'ES L20',1 resistant variety,14 moderately resistant varieties,18 susceptible varieties and 6 highly susceptible varieties were identified.In this study,the pathogen causing soft rot of Phalaenopsis in Zhejiang Province was identified,and the resistance information of some Phalaenopsis varieties was provided.This study laid a foundation for further research on the characteristics of disease occurrence and prevention methods and breeding disease-resistant varieties.