| The cotton and the processing tomato are the main industrial crops in Xinjiang province. The root rot diseases happened severely because of temperature changes in spring in xinjiang and the biological control effect of single strain was unstable. So we carried out the research of screen and efficacy of multifunctional strains formulation. The major results of this study are as follows:According to the results of growth characterization, antagonistic experiments between single strain and antagonistic examination of combinations in vitro, 23 combinations with superior suppressive effect than mono antagonistic strains were obtained. By further in vivo inoculation test, the combination BCL-8 was shown to have remarkable disease control and growth-promoting effect. The combination BCL-8 could promote seed sprouting of processing tomato. When treated with BCL-8, the seeds germination rate increased 10%, and the seedling height, fresh weight and dry weight of processing tomato seedlings increased 66.58%, 176.19% and 143.75%, respectively. The control efficacy of the combination BCL-8 to seedling Rhizoctonia rot of processing tomato were 40.08% and 55.53% under greenhouse and field conditions, respectively. The combination BCL-8 also increased production of processing tomato 24.32% in the field. The combination BCL-8 was composed of Bacillus sp. SL-13, SL-14 and SL-44.These three strains have been identified as Bacillus subtilis,GenBank accession number are FJ788426,FJ788427 and FJ788428.It was showed that the crude antagonistic substance was determined as a kind of protein by the reactions of triketohydrindene hydrate and biure. This protein was thermostable for it had strong inhibitory activities after treated at 120℃for 30min. It was proved that the protein was still active in buffer with pH from 4.0 to 10.0. The antagonistic effect of protein treated with various kinds of organic solvent was displayed that it was stable in ethnol, methanol, acetone, chloroform and so on. The inhibitory titer of protein exposed under ultraviolet radiation was similar to visible light. Proteinase K had no effect on its activity. Several pathogens were strongly inhibited by the protein, such as Fusarium oxysporum f.sp. lycopersici,Rhizoctonia solani Kuhn, Phytophthora capsici,Sclerotinia sclerotiorum, Acidovorax avenae sub sp Citrulli and Alternaria solani Sorauer.Antibiotic substances produced by B. subtilis SL-13, SL-14 and SL-44 were extracted by 30%-60%,40%-100% and 30%-50% ammonium sulfate-fractionation, respectively. Then antibiotic substances were partially separated by means of DEAE-Sepharose Fast Flow column chromatography, sephadex G-75 column and second round DEAE-Sepharose Fast Flow column chromatography. One active peak of B. subtilis SL-13, SL-14 and SL-44 were yielded during step elution. The antifungal proteins recycling rate were 6.1%,8.7% and 4.2%, respectively. The concentration were 0.0052 mg/mL,0.0087 mg/mL and 0.0021 mg/mL, respectively. The molecular weights of the purified protein were confirmed as 33kD, 24kD and 17.8kD by SDS-PAGE, respectively.Through examination of antifungal substances to B.subtilis SL-13, SL-14 and SL-44 and the plate experiments contain the chitin and the casein. We found that the B. subtilis strain SL-13 secretes proteins have high chitinase activity. The relations of B. subtilis SL-13 growth, chitinase activity and antifungal activity were studied in synthesized medium condition. With the extension of incubation the chitinase production had a positive correlation with the changing of antifungal activity. That is the chitinase was the main antifungal substances of strain SL-13. When detecting antifungal activity, the Rhizoctonia solani Kuhn treated by purified enzyme could not prolong, the cell wall broke, protoplasm leaked out, and the mycelia cracked. The microscopic analysis showed that the main effect of the purified enzyme was to degrade cell wall. The optimum temperature of the purified chitinase was 50?C. The enzyme was stable in the pH range of 5～9 for 1h at 50?C. It had an optimal pH of 7.0 when assayed with colloidal chitin as a substrate.The growth promotion and disease control strains and salt-relieving and growth promotion strains were combined to screening multifunctional strains formulation. According to the results of antagonistic examination in vitro and greenhouse and plot experiment in vivo, The combination BCL-8+Rs-5 was found have remarkable growth promotion, salt-relieving and disease control effects. The control efficacy of the combination BCL-8+Rs-5 to seedling Rhizoctonia rot of cotton were 54.41% and 51.06% under greenhouse and plot conditions, respectively. The cotton seedling dry weight was increased by 40.85%. The study result indicated the control efficacy of BCL-8+Rs-5 to seedling Rhizoctonia root rot of cotton was 16.24% in field. The treatment of drip irrigation with BCL-8+Rs-5 could obvious promote growth of cotton seedling. The effect of increase production of cotton reached 10.51%. The control efficacy of treatment of drip irrigation with BCL-8+Rs-5 to seedling Rhizoctonia root rot of processing tomato was 26.34%. The number of blossoms was enhanced 30.31%, and the number of fruits was enhanced 29.07%. The effect of increase production of processing tomato reached 5.04%.The activity of resistant enzyme (POD,PPO,PAL,SOD and CAT) increased after treated with BCL-8+Rs-5 in roots of cotton and processing tomato. It was obvious that the multifunctional strains formulation BCL-8+ Rs-5 have induction of systemic resistance. The influence of multifunctional strains formulation BCL-8+ Rs-5 is different to composition and quantity of plant rhizosphere microorganism. BCL-8+ Rs-5 can effectively raise the amount of the bacterial and actinomycete in soil and decrease the amount of the fungi. It conforms to the distributed tendency of healthy soil microecology. The result of 16S-rDNA DGGE fingerprint analysis showed consistent.
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