Effect Of Biocontrol Agents's Inoculated Methods On The Pepper Disease Prevention,Growth Promoting Function And Microecology

The study researched the effect of biocontrol agents's inoculated methods on the pepper disease prevention,growth promoting function and microecology, the results was below:1. The offered 15 strains included 3 strains actinomycetes, 1 strain bacteria and 1 fugi. The 3 representative stains, Act1,Act8 and B was studied in detail. According to actinomycetes shape and characteristics of culture, determined that Act 1 and Act 8 belonged to Streptomyce.sp, 16SrDNA sequence analysis showed that Act 1 was Streptomyces microflavus, B was Sphingobacterium multivorum.2. The interaction between the offered strains was tested by the methods of Oxford cup and agar block. The result of antagonism test in dish showed : There was not mutual inhibition between the actinomycetes 1 and the fungi F, The actinomycetes 2,8and fungi F had mutual inhibition on the growth; There was no mutual inhibition between the actinomycetes and the bacteria.The results provided a scientific basis for explaining the positive and negative effect of multi-inoculation.3. The inhibition effect was difference between the different inoculate quantity.①When the inoculate quantity was too low or too high (0.5g/kg or 2.5 g/kg), the inhibition effect was poor, The better inoculate quantity was 1.5g/kg, which the inhibition effect reached 66.7%.②In different pepper growth stages, the effect of biocontrol strains on the pepper's growth promoting was different. in the 0.5-2.5 g / kg, The average rate of biomass and fresh root resched 81.8% and 78.2% in seedling stage, 10.4% and 19.5% in mature stage. When the inoculate quantity was high (2.5 g/kg), the inhibition effect was the negative. In mature stages, the biomass and fresh root decresed 18.4% and 14.0% than the control.③It had a certain influence on the protective enzymes activity of pot leaves and roots. In the 12th day, the PPO activity of leaves increased by 23.1% -76.9%, in the 25th day, the PPO activity of leaves increased by 1.4% -54.8% and in the 27th day the PPO activity of roots decreased by 51.1% -67.2%.Comprehensive considering the inhibition effect and the growth-promoting, the better amount of the biocontrol strains was 1.5-2.0g/kg.4.Inoculation with biocontrol strains in seedbed:①could significantly increased the quantity of the bacteria and the actinomycetes, reduced the fungi number in capsicum rooting zone soil of plot experiment, The microbial flora of capsicum rooting zone soil changed markedly, it changed from fungi type to bacteria type. When inoculated with the antagonistic fungi F in the seedbed, the number of the bacteria and actinomycetes in the capsicum rhizosphere soil of plot experiment increased significantly by 166.7% and 46.2%, the ratio of bacteria to fungi and actinomycetes to fungi increased by 207.7% and 72.2%.②could significantly increased the number of Bacillus sp in capsicum rhizosphere soil, and reduced the number of Bacillus sp in capsicum root surface soil. The scope of increase and lessen were 7.5 %-246.8 % and 11.9 %-74.5 %.③could significantly increased the number of bacteria and actinomycetes in the capsicum root, among them the number of Bacillus sp also increased significantly; when inoculated with Act2, the number of bacteria,Bacillus sp and actinomycetes increased by 314.8 %,409.1 % and 77.3 %.④could significantly increased the yield of capsicum in plot experiment, when inoculated with Act8, the yield of capsicum increased by 48.8 % compared with the control. Inoculated with the antagonistic fungi and actinomycetes in seedbed, a large amount of antagonistic actinomycetes also been checked in capsicum rhizosphere and root surface soil of the capsicum harvest period(105-106g-1), which indicated that inoculation with the antagonistic microbial in the seedbed could colonized in the capsicum rhizosphere, and lasts a long time, it could make full use of the micro control strains continuance.5. Inoculation with biocontrol strains in the seedling and potted experiment①Single and multi inoculation with biocontrol strains had significantly growth promoting function. In the seedling experiment, total biomass and fresh root increased 127.2%-543.4%and 17.4%-265.2%, the average incresements were 313.6%and 124.2%. The growth promoting function still existed in the mature stages, the total biomass,fresh root and yield of pepper increased by 14.6%-60.5%,21.4%-108.1%and 35.9%-142.5%, the average increasement were 36.9%,47.9%and 75.4%. The growth promoting function in the pot experiment was resemble.②Single and multi inoculation with biocontrol strains had significantly prehition effect. Inoculating the microcontrol strains and P3 in the pot experiment, the inhibition effect of single and multi inoculation treatment were 20.6%-50.0%and 0-74.8%,the average were39.1%and 49.1%, in which the inhibition effect of 2F,Act2and F were 74.8%,24.9%and 50.0%.③The interaction between the biocontrol strains were difference in pepper's growth different stages. The strains showed inhibition on the biomass, which had inhibition in dish. When the strains that had no inhibition in dish mixes, the effect of growth promoting was unstable. The best treatment was 2B on yield, the⊿A ct and⊿B significantly reached 37.7 and 21.37 g/strain, but the stability of the result needed more research. 6. Inoculation with biocontrol strains in the seedling and potted experiment have function of PPO activity.①After inoculating biocontrol strains in seedbed, 45% treatments could increase the PPO activity of the pepper's root, which the average increasement reached 28.3%.②In the pot experiment, 63.6% of the leave's PPO activity increased comparing the control, the average incresment reached the 19.3%, 81.8%the root's PPO activity decreased in seedling stage by average decreased was 23.0% ; after inoculating P3 , 90.9% of the leaves'PPO decreased by 11%.③in mature stage, the PPO activity of leave and root decreased comparing the control; Inoculating Phtophthoraca Psicileo n. could promote the PPO activity's increasing.④The different multi inoculate treatment's multi inoculation effect of the potted pepper was different in the different stages. Inoculating with actinomycetes and bacteria could promote the increasing of PPO activity.