芒果蒂腐病病原葡萄座腔菌科真菌种类鉴定

Identification of pathogenic Botryosphaeriaceae species from mango stem-end rot

葡萄座腔菌科(Botryosphaeriaceae)是子囊菌中重要的代表性类群,可以引起果腐、环腐、轮纹等果实病害或采后货架期病害。芒果蒂腐病是芒果果实上的主要病害之一,该病具有潜伏侵染特点,在果实未成熟前就潜伏侵染,发病部位最初在果蒂处出现褐色小斑点,随后病斑迅速扩展至整个果实,发生褐变并散发出酸臭味,严重影响果实品质与产量^([1])。目前国外已报道引起芒果蒂腐病的病原真菌主要有葡萄座腔菌科色二孢属(Lasiodiplodia).

In order to identify the pathogen of Botryosphaeriaceae causing mango stem-end rot,tissue isolation method was used to process mango samples collected from Hainan,Guangxi,Yunnan,and Sichuan Provinces in China,and 58 fungal isolates were obtained.Among them,39 isolates were belonged to Botryosphaeriaceae,accounting for 67.24%.These isolates were identified based on morphological characteristics and phylogenetic analysis with internal transcribed spacer(ITS)and elongation factor 1 alpha(EF-1α).The results showed that there were four main species of Botryosphaeriaceae,including Neofusicoccum parvum(33.33%),Lasiodiplodia theobromae(30.77%),Botryosphaeria dothidea(28.21%),and L.pseudotheobromae(7.69%).The mango stem-end rot caused by L.pseudotheobroma was firstly reported in China.The virulence of the four species was tested by in vitro inoculation and the results showed that all isolates were pathogenic,among which L.theobromae,L.pseudotheobroma,and N.parvum were the“strong”grade,and B.dothidea was the“middle”grade.