木霉菌对几种植物病原菌的拮抗作用

为探明木霉对植物病原菌的拮抗作用效果,筛选出优势菌株,从长沙地区的15种作物根围采集到27份土壤样本,经室内分离、纯化得到28个木霉菌菌株.利用对峙法和稀释法测定了28个菌株对花生立枯病菌、水稻纹枯病菌、水稻恶苗病菌、辣椒炭疽病菌、白术白绢病菌的拮抗作用,得到1株对5种供试病原真菌均有强烈拮抗作用的菌株,经鉴定该菌株为哈茨木霉.对峙培养可观察到,多数情况下,接种后2 d内木霉与病原菌接触,随后覆盖或侵入病菌菌落,抑制其生长,其抑制程度随木霉孢子浓度的降低而减弱.温室盆栽试验发现,哈茨木霉对番茄立枯病防效显著,喷洒高浓度的哈茨木霉分生孢子悬浮液防效可达80%以上,且具有持续防效和刺激作物生长的作用.

Study on antagonism of Trichoderma to fungal pathogens

In order to get the effect of mold control plant pathogeny,and find the best one,28 Trichoderma spp.strains were isolated from 27 soil samples collected from the rhizosphere of 15 different crops around Changsha,their antagonisms to Rhizoctonia solani,Rhizoctonia solani,Fusarium moniliforme,Collectotrichum capsici,Sclerotium rolfsii were tested by dual culture and dilution.One strain could antagonize five tested fungal pathogens and was identified to Trichoderma harziaum.The results in dual culture demonstrated that in most cases,Trichoderma spp.made contact with the pathogens inoculation subsequently the pathogenic colonies were either overgrown or invaded by Trichoderma spp.,leading to the inhibition in pathogen growth.The control extent along with spore concentration debasement and reduction.Greenhouse pot experiment showed,the effect of Trichoderma harziaum control tomato seeding wilt is very salience.Insufflation the high conidiophores suspend liquid of Trichoderma harziaum,the prevention and cure result can reach 80%,which has continuance control effect and promote plant growth.