杧果蒂腐可可球二孢菌致病力测定及杧果主要品种抗病性评价

Evaluation of pathogenicity of Botryodiplodia theobromae and resistance to stem-end rots on the main varieties of mango

【目的】测定杧果蒂腐病可可球二孢(B.theobromae)不同菌株的致病力及评价杧果品种的抗病性,为杧果蒂腐病防治技术的研究奠定基础。【方法】采用室内人工接种的方法,对124个B.theobromae菌株进行致病力测定,并针对11个杧果品种进行抗病初步测定。【结果】B.theobromae菌株之间致病力有较大差异,强致病力菌株占28.23%,中等致病力菌株占66.93%,弱致病力菌株占4.84%。同一品种资源分别接种5个不同菌株,抗病性存在较大差异;但是,通过接种B.theobromae后的平均病情指数进行抗性分级,对多个菌株的抗病性进行综合评价发现,‘象牙’为高感(HS)材料,而其余10份材料均表现为感病(S)。【结论】杧果可可球二孢是引起杧果蒂腐的优势病原菌,强致病力和中等致病力菌株在海南分布广泛;供试11份杧果材料中没有对B.theobromae菌株表现抗病的杧果品种。

【Objective】Mango stem- end rot(Botryodiplodia theobromae)is the main fungal disease ofmango during storage. It was also found in most mango growing regions of the world. It is one of main post-harvest diseases causing production loss of mango in Hainan,which is very difficult to be controlled. Thestudy aims to clarify the pathogenicity of B. theobromae and resistance to stem-end rots on mango variet-ies,and provide the fundation for the prevention and treatment of mango stem- end rot. 【Methods】Through artificial inoculation in plastic boxes,pathogenicity of 124 stains of B. theobromae from mangofruit were tested. Resistances of 11 mango varieties to stem-end rot were evaluated by inoculation with 5strains of B. theobromae.【Results】The results showed that all stains had different pathogenicity,the highvirulent strains accounted for 28.23%,the median virulent strains accounted for 83.0%,and the low viru-lent strains accounted for 5.65%. The resistances of same variety to stem-end rot depended on the strainsinoculated. The stem-end rot resistances were graded by average disease index(DI)of 5 strains of B.theobromae. Based on the comprehensive evaluation of resistance to multiple strains,‘White Ivory'per-formed as high susceptive(HS),while other 10 materials as susceptive(S).【Conclusion】B. theobromae was considered as prevalent pathogens causing mango stem-end rot,and the high virulent strains and themedian virulent strains had wide distribution in Hainan. There was no stem-end rot resistant mango vari-ety among the 11 tested mango materials.