Pathogens analysis of soft rot disease of imported pitaya in Shanghai
上海市进口火龙果软腐病病害分析

In this study, the major pathogens that caused soft rot disease of imported dragon fruit were studied morphologically and molecularly. Two strains of Fusarium were identified in this study, which respectively belongs to Fusarium oxysporum and Fusarium dimerum. F. oxysporum was the most important pathogen which caused postharvest rot on imported pitaya. The most optimum temperature for F. oxysporum growth and pathogenicity was 25 °C. In addition, there was a positive relationship between pathogenicity and illumination. It could neither grow nor form lesion under lower temperature (5 °C) and higher temperature (45 °C), its pathogenicity became weaker under 15 °C and 35 °C. Further analysis showed that it could also cause postharvest rot on banana, tomato and grape. Taken together, our results analysis the key pathogen caused postharvest rot on imported pitaya and provide a useful reference for making measures towards the disease.