Studies On Screening Of Antagonistic Microbia Of Phytophthora Capsici And Applying Of Biocontrol Agents

1. According to Kehe Law, a strain of pytophthora capsici was isolated andidentified with strong infection capacity from infected stem pepper in Qishan region,leaded pepper blight epidemic.2. Screening 4 strains trichoderma and 10 strains chaetomium from 58 strains givenfungi including 32 strains trichoderma and 26 strains chaetomium, and 2 strains from108 strains actionmcetes, that were 0108 and 0110. Disease rate of M1.2,M1.3,M7and MJ was 9.5%,2.4%,4.8% and 7.1%, it decreased 83.4%,90.5%,88.1% and85.8% than contrast; Disease rate of CHI and CHD was 0 respectively, Disease rate ofCHE,CHP,CHT,CHC,CHF,CHJ,CHM and CHQ were under 20%; Disease rateof 0108 and 0110 was not obviously to contract under lever 1% in divergence. Itshown that 16 screening Antagonistic Microbial had inhibition very capable, theycould be reserve strains to research to bio control.3. Six given antagonistic microbial inhibited pytophthora capsici obviously. Inpotted plant experiment ,four strains (Act1,Act2,F and B) verge of disease ratewere from 13% to 25% ,divergence was not obviously to contract under lever1%,verge of disease rate decreased from 73% to 86% compared pathogen treatment.In field experiment, the average disease rate was 5%of Act2 in six different time,decreased 60% to contrast. Different antagonistic microbial with different efficacy,it changed by inoculated manner and unit of given strains. Dipped treatment wasbetter than mixed soil treatment in efficacy.4. Six given antagonistic microbial increased pepper output and promoted rootgrowth obviously. Pepper output increased from 55% to 76% after inoculated Act3,Act4, B and F respectively. Root weight increased from 22% to 49%. Unit of twostrains increased pepper output except unit of Act2 with F. Pepper output growthrate of Act3, Act4 mixed with B was 136% and 92%.5. Six given antagonistic microbial and two strains screened (0108, 0110) impactedpepper root microbial system.Act1 and B could colonize in pepper root spot verycapable. The number of living antagonistic microbial was 160×105cfu/g,321×105cfu/g. Efficacy and growth promotion were the result of colonizing and thaneffected microbial system of pepper root spot.6.Plat experiment result shown, Three strains (Act2,Act3 And Act4) distorted hyphaof pytophthora capsici by producing antibiotic, but Act1 inhibited hypha growthby multiplication themselves or producing enzyme.7.Four given strains (Act1～Act4)could produce large amount of living sporescultivated by solid fermentation. Corn flour was the best carbon and nitrogen.8. Six given strains were determined by the capacity of using 14 kinds of carbon and14 kinds of nitrogen, and the resistance of 10 kinds of antibiotic and 2 kinds ofpesticide. It would provide scientific basis for classify and identify.