The Reserch On The Pesticide Resistance Transformants Of Chaetomium Cupreum

The experiment takes Chaetomium cupreum and its pesticide resistance transformants C1, C2 as material and researches on the C. cupreum carbendazol-resistance transformants from their physiological characteristics, cultural characteristics, biological control characteristics and cell wall degrading enzyme characteristics. The experiment can provide the scientific theory for the C. cupreum carbendazol-resistance transformants to apply in the fermentation production and make it better to use in the practical production.The experiment on the carbendazol-resistance level of transformants shows that: the resistance level of transformants C1, C2 to the carbendazol can reach to 40~50μg/mL, which is more than 70~80 times of wild-type strains.The research on the physiological characteristics of the transformants shows that compared with wild-type strains, the transformants have great changes in the colonial morphology, growth rate, and hypha morphology. The mainly changes perform in four aspects: the color of the colony darker, the growth velocity lower, the interval of the hypha bigger and the color of the pertithecium darker. We can also observe the transformants through changing cultivate condition. The results show that PSA medium and the basic medium are the best for the colony growth and the production of the scopospore production of the transforms, the next is PDA medium and the Czapek is the worst. The optimization pH value and temperature range for the transformants growth are pH 5.5~7, 25℃, respectively. The transformants can take galactose, cane sugar better as carcon source and peptone, extractum carnis as nitrogen source. In contrast, amylomaltose, galactosylglucose, urea are bad for the transformants growth.The inside antagonism experiment shows that there are no differences between transformants and wild-type strains when they antagonist with Rhizoctonia solani, Sclerotinia sclrotiorum and Aftrnaria alternata. Compared with wild-type strains, the antagonism of the transformants to Fusarium oxysporum become weaker and both the transformants and the wild-type strains don't show strong antagonism to the Phytophthora sojae. Through the experiment we can see that the transformants C1, C2 can be taken as the good biological control strains to apply in the practice.The experiment on the cell wall degrading enzyme production of the transformants shows that both C. cupreum and transformants can produceβ-1,3-glucanase and chitinase induced by five pathogenic bacteria cell wall, among which the R. solani and A. alternata can be considered as the best inducer. The characteristics of the transfomants enzyme production are equal to that of the wild-type strains, excep that, the time of enzyme production of transformants are 2~3 days later than the wild-type strains. Through the comparation we can make a conclusion: the level of the transformants producing cell wall degrading enzyme is related to the antagonism to the pathogenic bacteria, which demonstrates that the cell wall degrading enzyme plays an important role in the antagonism.From the research on the four aspcets, the transformants C1, C2 which are the good strains in the biological control have good effect on the pathogenic bacteria and producing cell wall degrading enzyme. Not only they can contol the pathogenic bacteria by themselves, but also they can use with low dose pesticide to construct the synthesized control system to improve the efficiency.