Studies On Pleurotus Ostreatus’s Resistence To Trichoderma

Trichoderma spp.is a kind of competitive fungi in mushroom which causes serious loss in production.Chitinase is a kind of enzyme produced by animal,plant and microorganism with many of them have the activity of antifungal.A strain of Trichoderma which was isolated from Trichoderma affected Pleurotus bags and three strains of Pleurotus ostreatus-Nongping No.l,(CCMSSC)00358 and(CCMSSC)00406-were used in this study to explore the anti-Trichoderma function of chitinases in P.ostreatus.CYM(Complete yeast medium)supplemented with dried Trichoderma powder(sterilizated),CYM(the control)that had been used to cultivate Trichoderma(sterilizated)and CYM were used to cultivate P.ostreatus.The protein content and chitinolytic activity were measured in these medium.The results showed that:the mycelium of Trichoderma can inhibit the growth of Nongping No.1 and 00406 intensively;the culture liquid of Trichoderma is more inducible to P.ostreatus to produce more amount of protein;there is no apparent difference among strains in protein content among different treatments to the control.Chitinolytic activity was detected by a method of 3,5-dinitrosalicylic acid and the results showed that there is no apparent effect of mycelium or culture liquid of Trichoderma on chitinolytic activity of P.ostreatus,00406 showed the highest chitinolytic activity.Chitinases activity in dual cultures of Trichoderma and P.ostreatus were studied.Firstly separated the crude protein by native-page,then reacted in-situ with three kinds of fluorogenic substrates,the species responsible for the production of each enzyme type was determined by extraction of proteins from single cultures of Trichoderma and P.ostreatus.The results showed that:P.ostreatus produced N-acetylglucosaminidases with apparent molecular masses of 123 KDa,177 KDa and 155 KDa.No more kinds of chitinases were induced by Trichoderma.P.ostreatus is not a inducer of chitinase for either,when there is no chitin in the medium,there is no chitinase.Trichoderma produced 5 kinds of chitinase when growing on a medium with chitin as the single carbon source,those are:intracellular N-acetylglucosaminidases of 93 KDa,extracellular N-acetylglucosaminidases of 82 KDa,extracellular chitobiosidase of 25 KDa,extracellular endochitinase of 34 KDa and 24 KDa.