Isolation And Identification Of Penicilliumand Trichoderma From Oyster Mushroom Farm And Fungicide Screening

Forty-seven strains of Penicillium and Trichoderma were isolated from materials, substrate bags, spawn and fruiting body of oyster mushroom Pleurotus sp. from Nanning mushroom farms, they were identified to3species of Penicillium and3species of Trichoderma according morphological characteristics and rDNA ITS1-5.8S-ITS2sequences, biological characteristics of these strains were observed and their antagonistic effect to Pleurotus sp. were investigated, and the fungicides to control of these strains were also screened. The results are in the following:All of the strains obtained in this study were assigned to Penicillium and Trichoderma, they are Penicillium brecicompactum, Penicillium citrnumt and Penicillium thomii and Trichoderma harzianum, Trichoderma pleuroticola and Trichoderma viride, according to the morphological characteristics and rDNA ITS1-5.8S-ITS2sequences. Trichoderma spp. were found frequently on the cultivation bag and raw material, but Penicillum spp. appeared more from the air and the fruit body of mushroom. The colony of the Trichoderma extended more quickly, and with fewer spores, as to the Penicillum, its colony were confined by slower extending speed, but with a great quantity spores which could easy germinate.Pathogenic fungi of Penicillum and Trichoderma have stronger adaptability. Like T. pleuroticola, the optimal temperature is30to35℃, the optimal water content is80%, the optimum pH value is7. As to T. viride, the optimal temperature, water content, and pH value were25℃,70%and8individually, to T. harzianum,20to30℃,80%and8separately, to P. citrinum,30℃,70%and7, to P. thomii,20to30℃,70%and8, to P. brevicompactum,20℃,50%, and8. All these characteristic of the pathogen fungi were similar to oyster mushroom, and they all could hardly grow below40%of water content, but could grow under the pH value of4to11, and they all were inhibited when the temperature were5to10℃and35to40℃.The plate antagonistic experiment showed that three species of Trichoderma have stronger pathogenicity to oyster mushroom, the other three species of Penicillium were weaker, but still inhibited the mycelium growth of oyster mushroom.All test6different fungicides had certain inhibition to those pathogen fungi. Bromogeramine had the best effect,3%hydrogen peroxide,84disinfectant,5%lysol, mineral chameleon, and75%alcohol also had certain inhibition. They all inhibited better the growth of three species of Penicillium than that of the three species of Trichoderma.