枣果霉烂病病原鉴定(一)——引起新疆枣果霉烂病的几种曲霉菌的分离鉴定

Identification of the Pathogen Causing Jujube Fruit Mildew(Part Ⅰ)-Isolation and Identification of Aspergillus fungus Causing Jujube Fruit Mildew

【目的】枣果霉烂病是枣果产后的重要病害,曲霉菌是枣果霉烂最重要的致病菌。目前,国内外对引起枣果霉烂病的病原种类报道甚少。明确新疆枣果霉烂病的病原种类及优势致病种群,有效防控该病的发生和危害。【方法】通过广泛采样、组织分离和回接证病对大量病样进行系统分离;对几种致病曲霉菌进行形态鉴定、分子验证及致病性比较。【结果】曲霉属真菌为枣果霉烂病的最主要病原;分离得到的大多数曲霉属的单孢分离菌株对枣果具有明显的致病性;致病的214个曲霉属单孢菌株分属于5个种,分别为黑曲霉、黄曲霉、赤曲霉、赭曲霉和聚多曲霉;其中黑曲霉的分离频率最高,致病性最强。【结论】引起新疆枣果霉烂病的曲霉有5种,其中黑曲霉为优势致病种。

[ Objective] The Jujube fruit mildew is the major disease of postharvest jujube fruits, and Aspergillus fungus is the most important pathogenic fungus of jujube fruits mildew. At present, there is no substan- tial report within or outside the country about the pathogen species causing jujube fruits mildew. Clarifying pathogen species and advantaged species of jujube fruits mildew in Xinjiang is significantly important to control the occurrence and damage of this diseases. [ Method] Widely sampling, tissue isolation and tie -back method were used in systematic isolation for large number of disease samples. At the same time, morphological analy- sis, molecular analysis and pathogenicity comparison were used for identification of some pathogenic Aspergillus fungus. [ Result]The isolation results showed that Aspergillus spp. fungus is the major pathogen which causes jujube fruits mildew. Separation with the majority single spore isolates of Aspergillus spp. have got pathogenicity to jujube fruit. 214 single spore isolates ofAspergillus spp. which have pathogenicity belong to 5 species,they are A. niger,A, flatus,A, rubrum,A, ochraceus and A. sydowii,among which, A. niger had the highest isolate rate and the strongest pathogenicity. [ Conclusion] There are 5 species of Aspergillus that cuase jujube fruits mildew in Xinjiang, among which, the advantaged pathogenetic species is A. niger.