| In order to find out new application approaches of two important microbial insecticides -entomogenous fungus and bacteria,to prolong their effective periods,to enhance insecticidal results and to counterbalance the deffects of the two kinds of microbe which were liable damaged by ultraviolate in nature,we devised 12 kinds of cimposited latexes and 10 composited powders of fungus and bacteria.Through a great many experiments to measure their biological activity and virulence to pests,we come to two to three groups of components which were insensitive to environmental factors such as ultraviolate etc. These groups can quickly output their effects . They are highly effective to pests and can be stored for a long time .We also isolated a validly pathogenic fungus from the pupae of Hilicoverpa assulta.lts biological and ecological characteristics were studied as well. 1 The biological and ecological characteristics of several fungal strainsThe entomogenous fungus P.s is adaptive to low temperature,has a sticky growing potency. In the progress of its growth,the shape of its spore is sphere,its color is green or yellow. On conditions of 15,25 and 35 centigrade,it grows best at 15 centigrade,follows by 25 centigrade. It stops growing at 35 centigrade and soon died. On two kinds of medium of SDAY and PDA,it grows stronger on SDAY media than on PDA. but on PDA it can produce spores earlier and has a larger sporulation. Transplanting P.s with conidium suspension grows better than with conidium powder. So the best cultivating way to P.s is to transplant it with conidium suspension on media SDAY at the temperature of 15 centigrde. In this manner P.s grows 0.67 centimeter per day averagely.The Penicillium strain P.s can produce acid substances and lower the liquid pH as well as shallow the liquid media colors when cultured in it. The growth circumstance is that the Beauveria bassina strain 5S03 shows the best,P.s is next to it and the Metarhi-ium anisopliae strain Ma4 shows the poorest. On the other hand. P.s's sporulation is most significant. The growth circumstances can also deprived from four artificial medium. Among them. P.s grows best on the D component,the next is the B and A component,component C shows poorer. The four artificial medium's compositions are respectively as follows:D-(wheat bran:maize powder:filtered potato liquid =4:1:4)B-(wheat bran:filtered potato liquid =5:1)A-(wheat bran:maize powder =5:1)C-(wheat bran:maize powder:filtered potato liquid =4:1:1)2 The virulence of Penicillium strain P.s to pestsTo treat Myzus persicae and second -instar larvae of Helicoverpa armigera with P.s conidium suspension,according to their LT of four strains of fungi against Myzus persicae,the results showed that P.s strain actived most quickly,following 5S03 and Ma4,the Nomuraea rileyi strain Nr96-l is next to them. The significant analysis of the four fungus strains against Myzus persicae showed that the mortality rates of Ma4 strain and 5803 strain are most magnificent,P.s is the poorest and has significant difference compared with other fungi. To treat against second -instar larvae of Helicoverpa armigera with six strains of fungi,it can be put forward that 5S03's mortality rate is higher than other strains,P.s is next to 5S03,the poorest is Ma4. The mortality rate of P.s against second -instar larvae of Helicoverpa armigera is average. As analysed above,we selected fungi of 5S03 and P.s to composite with bacteria in the end.3 Measurement and evaluation of composited latexes of bacteria and fungus Put P.s strain powder and 5S03 strain powder respectively into the Bt latexes,thenput other surfactants and UV-protectants into them. In the whole we obtained 12 kinds of equable composited latexes. After storing them for one month,four months and a year,the tests of their microbial activity and their virulence to object pests were made. During every stage,the vitality of the bacteria and fungus were lowered comparing it with the former stages. The bacterial viatality of composited latexes a and...
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