| Ralstonia solanacearum is a soil-borne pathogenic bacteria, which does serious harm to the production of tobacco. It was significant to develop a efficient microbial fertilizer for biological control to tobacco bacterial wilt, because of no safe and effective bactericide. In our laboratory, a kind of highly effective microbial fertilizer, preventing tobacco bacterial wilt, was developed by using antagonistic bacteria 011 and 2-Q-9. Some basic researches to the use of the product were done in this experiment.The optimized and the collocation of selective medium for detecting Pseudomonas solanacearum in the soil was that:beef extract medium 100 mL; crystal violet2.5×10-2μg/mL; TTC2.5×10-2μg/mL; ampicillin capsules 9.996×10-5μg/mL; ofloxacin tablets 9.990×10-7μg/mL; roxithromycin tablets,2.998×10-6μg/mL; cefradine capsules3.000×10-6μg/mL; acetylspiramycin tablets,1.998x×10-5μg/mL; clarithromycin dispersible tablets 2.999×10-5μg/mL; azithromycin capsules 1.999×10-6μg/mL.The result of detecting tobacco bacterial wilt in soil from Xiangxi, Yongzhou, Chenzhou by the selective medium demonstrated that the number of Pseudomonas solanacearum in soil samples from Xiangxi was larger than that from Yongzhou, and that from Chenzhou was relatively small. There was a positive correlation between disease index and the number of bacteria, and the amount of tobacco bacteria in the soil with antagonistic bacterial fertilizer was smaller than that in common soil.The results of the interaction test between antagonistic bacteria and blight bacteria fermentation of manure showed that:there was no antagonism between antagonistic bacteria 2-Q-9, blight bacteria fermentation m1,DB2 and the fermentation broth, which indicated 2-Q-9 and main microbe in the microbial fertilizer could grow collaboratively, and it was feasible to make microbial fertilizer by using 2-Q-9 and fermentative bacteria; there was antagonism between antagonistic bacteria 01 land fermentation bacteria m1, DB2 and the fermentation broth, and it was primarily identified that using antagonistic bacteria 011 and fermentation bacteria m1, DB2 to produce microbial fertilizer is not feasible.The colonization test of tobacco antagonistic mutant strain 011 and 2-Q-9 in tobacco efficient fertilizer showed that the number of antagonistic bacteria increased rapidly from 20 to 30 days, but the amount decreased'after 30 days. It showed that the strains 011 and 2-Q-9 could colonise in short time in the fertilizer, but were not suitable for long-term colonization.Tobacco antagonistic mutant strain 011 and 2-Q-9 can be successfully recovered from the soil, the results showed that the amount of the strains 011 recovered from unsterilized soil was larger than that from sterilized soil from15 to 45 days; and the amount of the strains 2-Q-9 recovered from unsterilized soil was larger than that from sterilized soil from15 to 75 days; during the whole growth process, the number of bacteria significantly decreased after 60 days.The results indicated that strains 011 and 2-Q-9 could collaborate with soil microbes, and the critical period of using fertilizer next time was the 60-day.Through the application of microbial fertilizer in the small district and in field, the results showed that in the small district the control efficiency of antagonistic bacteria fertilizer with strains 011, strains 2-Q-9 and the mixture of both strains were 71.20%, 49.28% and 83.39% in the small district, respectively. Which indicated that the control effect of mixed fertilizer is better than that of single bacterial fertilizer; in field, the control efficiency of the mixed fertilizer in Chenzhou and Yongzhou were 90% and 37.71%; The control efficiency were higher than common agricultural streptomycin in both small districts and fields.
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