油菜花瓣附生真菌区系及对核盘菌拮抗作用的研究

Mycoflora analysis on rape flower and selection of antagonisitic fungi to Sclerotinia sclerotiorum

采集油菜不同部位脱落花瓣和未脱落花瓣进行附生真菌区系的分析,得到1908个菌株.除了核盘菌Sclero tiniasclerotiorum外,其他真菌经鉴定后主要属于10个属,它们是短梗霉属Aureubasidiumspp.、镰刀菌属Fusariumspp.、交链孢菌属Alternariaspp.、葡萄孢属Botrytisspp.、黑葱花霉属Periconiaspp.、曲霉属Aspergillusspp.、黑孢属Nigrosporaspp.、青霉属Peniccilliumspp.、木霉属Trichodermaspp.和附球孢菌属Epicoccumspp..其中,短梗霉菌、镰刀菌和交链孢菌为优势真菌群.通过菌丝间的相互作用、对峙培养方法测定160个菌株对核盘菌抑制作用.结果表明,供试菌株与核盘菌之间存在重寄生作用和溶菌作用等方面的拮抗机制.并初步筛选得到了一批拮抗作用较强、定殖能力也强的菌株.

From 2001 to 2002,investigation was carried out on mycoflora of rape petals. (1 908) isolates were obtained from new opened petals and senescent petals which were collected from stages of emerging bloom, full bloom and fall bloom. Except Sclerotinia sclerotiorum, there were other fungi, such as Aureubasidium spp.,Fusarium spp.,Alternaria spp.,Botrytis spp.,Periconia spp.,Aspergillus spp.,Nigrospora spp.,Peniccillium spp.,Trichoderma spp.,Epicoccum spp.. The dominant mycoflra were Aureubasidium spp., Fusarium spp. and Alternaria spp., followed by them were Botrytis spp.,Periconia spp. and Aspergillus spp.. The average isolation frequency of Aureubasidium spp. was the highest, followed by that of Fusarium spp..160 isolates were selected from identified fungi from rape to test their antagonistic effect on S.sclerotiorum by the methods of dual culture.The properties for a antagonist, which were suggested as necessary for S.sclerotiorum, including hyphal interaction, direct parasitism, strong competitive to S.sclerotiorum were observed in vitro. Among them,10 isolates were selected(A4,F6,Au2,As1,-B1,Pe7,AU6,As2,F3,Pe5 ),antagonism and activity of them were strong.