防治油菜菌核病的木霉和粘帚霉菌株筛选及生防的初报

2002年6月至12月中旬,用4批共200颗菌核作诱饵,分离到粘帚霉(Gliocladiumspp.)、木霉(Trichoderma spp.)、镰刀菌(Fusariumspp.)、青霉(Penicilliumspp.)、毛霉(Mucorspp.)、根霉(Rhizopusspp.)、曲霉(Aspergillus spp.)、腐霉(Pythiumspp.)和少量难鉴定菌株,共计171个菌株,其中粘帚霉80株、木霉55株,分别占46.8%和32.2%,在不同采样期内均为优势种群。所诱捕的木霉经鉴定分为7个种,哈茨木霉和康氏木霉出现较早,而黄绿木霉和拟康氏木霉出现较迟。通过测定所获得木霉菌株对核盘菌的拮抗作用,筛选出Tk1、Th2生防潜能较好的菌株。经离体叶片测定,Tk1和Th2对油菜菌核病的防治效果分别达90.6%和89.1%。

Screening for Trichoderma spp. and Gliocladium spp. Against Rapesee Sclerotinia Stem Rot and Primary Study of Biocontrol

fungal strains were isolated from the surface and inside of sclerotia buried in the soil of rapeseed field to study the fungal varieties and their quantity variation at the different time from June to December, 2002. The fungi were identified as Gliocladium spp., Trichoderma spp., Fusarium spp., Penicillium spp., Mucor spp., Rhizopus spp., Aspergillus spp., Pythium spp.as well as some unidentified ones. Among them, Gliocladium spp.were 54 (46.8%) and Trichoderma spp.55 (32.2%) and Fusarium spp.13 (7.6%) respectively which were dominant groups at the different time of sampling. Trichoderma spp.belonged to 7 species, in which T.harzianum and T.koningii appeared earlier than T.aureoviride T.pseudokoningii. The strains Tk1 and Th2 that possed stronger potential ability to biocontrol were selected through the antagonistic tests against Sclerotinia sclerotiorum. The efficiency of biocontrol of Tk1 and Th2 were 90.6% and 89.9% respectively on the leave in vitro.