梨胶胞炭疽病菌的分离、鉴定及其生物学特性

摘要

[Objective] This study aimed to explore the biological characteristics of Col etotrichum gloeosporioides in pears. [Method] Twenty-five C. gloeosporioides strains were isolated and identified from the diseased samples. Their pathogenicity was identified by inoculating the surface of punctured pears with fungal discs. The effects of different temperatures, pH values, carbon sources and nitrogen sources on the growth of C. gloeosporioides mycelia were explored by incubating fungal discs on the center of plates. [Result] Among the twenty-five C. gloeosporioides strains, three had strong pathogenicity, and eighteen had intermediate pathogenicity, and four strains had weak pathogenicity. Those highly-pathogenic strains had darker colonies, with dense mycelia, whereas those lowly-pathogenic ones had white colonies, with sparse mycelia. Those with fast-growing colonies showed strong pathogenicity, while those with slowly-growing colonies displayed weak pathogenicity. There was no relationship between conidia yield and pathogenicity. The optimum temperature for the growth of C. gloeosporioides mycelia was 25-30 ℃, and the optimum pH was 5.0-7.0. C. gloeosporioides could make use of various carbon sources (monosaccharide and disaccharide), inorganic and organic nitrogen sources, and the optimal carbon source and nitrogen source were sucrose and beef extract, respectively. [Conclusion] Our study benefits further understanding of C. gloeospori-oides and helps to control pear anthracnose more effectively.%[目的]旨在探究梨胶胞炭疽病菌的生物学特性。[方法]从采集的病样分离并鉴定出梨胶胞炭疽病菌25株。采用梨果表面刺伤后接种菌块的方法，观察炭疽病菌对砀山酥梨的致病性。平板接种炭疽病菌菌块，测试不同培养温度、pH 值、碳源、氮源对炭疽病菌菌丝生长的影响。[结果]参试的25株炭疽病菌中3株致病性较强，18株致病性中等，4株致病性较弱。致病性强的菌株其菌落颜色较深，菌丝浓密；致病性弱的菌株其菌落颜色均为白色，菌丝稀疏。菌落生长快，菌株的致病性较强；菌落生长慢，菌株的致病性较弱。菌株的产孢能力和致病性之间无相关性。梨胶胞炭疽病菌最适生长温度为25～30℃，最适生长pH 值为5．0～7.0；菌丝对多种单糖和双糖等碳源及有机氮、无机氮均可利用，最适碳源为蔗糖，最适氮源为牛肉浸膏。[结论]该研究有利于加深对梨胶胞炭疽病的认识，有助于更有效地控制该病。