Research On Isolation, Identification And Biological Characteristic Of A Strain Of Metarhizium Anisopliae CQMa117

The occurrence of soil pests of sugarcane has become a major factor for confining the sustainable development of the industry of planting sugar cane and yielding the sugar. Because of soil pests existing in the soil and the time of victim long time, the control of the soil pests are difficult recognized at home and abroad. The control methods have agricultural control,physical control,chemical control, and biological control. Using of chemical pesticides excessively in the past is an important factor of causing the current deterioration of the agricultural ecological environment, as well as inefficient agricultural production. Biological pesticides have some excellence .Such as simple,effective,ecological and environmental security. It can be fully or partially substitute for chemical pesticides.So the biological control will be more and more important in the near future in the fight against soil pests. In recent years, the study of fungal pesticide formulations has become a hot research. The fungus ,such as Metarhizium anisopliae and Beauveria bassiana , represent biological pesticides in biological control of pests is playing more role.The purpose of this study is using of the rich micro-organisms resources in soil and using of rhizosphere enrichment method to obtain a stiff sugarcane root alternatus larvae infected by a fungal. We isolate a strain ,which is a biocontrol fungi with high-toxicity, high production capacity ,suitable soil pests and efficient in different environments, security. We use the strain as a material to study its biological characteristics, taxonomic status, insecticidal spectrum, as well as liquid-solid two-phase fermentation of the optimum conditions to conduct .The main contents of study include separateing and purifying a Metarhizium strains form the stiff sugarcane root alternatus larvae,determining its biology status form the biological characteristics and the ITS sequences,confirming the best condition for grew and sporulation and solid ferment by the single experiment and orthogonal experiment,making sure of its virulence and insecticidal spectrum by using different methods of application for the sugarcane root alternatus larvae,determining its esterase isozyme and seting up a esterase enzyme type. Those will carry out an effective confirmation for the virulence of the strain . The main thesis of research results are as follows:â‘ We successfully isolated a strains of Metarhizium anisopliae ,whch is cultivating easily,owning high toxicity,safe and effective.We determine its biology status according as its morphological characteristics,biological characteristics and its of ITS1-5.8-ITS2 rDNA sequence alignment. The CQMa117 was identified as Metarhizium anisopliae var.major.â‘¡We first separate determine the optimum basal medium, the culture temperature and the culture pH .Then separately choose from three aspects (carbon source, nitrogen source, trace elements)as a single factor,which can able to promote growth and sporulation. Lastly we choose from three better factors to determine the strain of solid cultivate in the best conditions by orthogonal experiment. The mycelium of strain grew best and sporulation was the largest by when the carbon source was saccharose, nitrogen source was carbamide and microelement was added in when the condition was pH6.0 and 25℃.â‘¢On the base of the optimum solid foundation on culture conditions, we separate choose from the basic materials for solid-state fermentation , liquid for solid-state fermentation, nutrition liquid for solid-state fermentation. Then we we choose from three better factors to determine the strain of solid-state fermentation in the best conditions by orthogonal experiment. The best solid foundation for ferment is:the basic materiel flour :indian meal(95:5),which acceded to the liquid that containing 0.01%Cu²⁺ of 1/2SDAY.â‘£We determine its virulence for the sugarcane root alternatus larvae by the using poison soil and drip method. Simultaneously make sure of the insecticidal spectrum of strains and identify esterase isozyme enzyme type of the strains. Those labor offer enough preparative for the follow-up study to the strain.