Studies On The Biological Properties And Promoting Capsicum Growth By Endophytic Bacillus In XiNing City

The capsicum is an important plant for the agriculture of Qinghai province. Research on endophytic bacteria from capsicum not only lays the foundation of further improving the yields of capsicum in Qinghai province, but also dues to its non-toxic, pure natural advantages. two strains was collected from 6 root nodules from Xining Plant nursery. Datong and Minhe County, Its biological characteristics and plant growth promoting effects with capsicum were preliminarily studied. The results as follows: X1 strain was Bacillus subtilis, W1 strain was Bacillus licheniformis.Mutanted by antagonism against the rifampicin(100μg/ml) and inoculated by dipping seeds,daubing leaves,and pouring roots,X1(Bacillus subtilis) strain was proved to be able to colonize inside of capsicum.If capsicum seeds were soaking for 24h in bacterial suspention with 5×10⁶cfu/ml concentration before sowing,the target bacterial could be isolated from the capsicum seedlings late.The results also showed that the strain was able to get into the plants initiatively,and live and move in the plants.The inoculation by daubing leaves could get better result.The result of plant promoting growth by X1 showed that the bacteria could accelerate growth of capsicum no matter which inoculation method was used.But the best one was daubing leaves.the mechanisms of promoting plant growth by X1 were investigated.the results showed that X1strain could colonize in plant,and quantity of colonization was correlation with plant promoting. the bacteria could increase the energy of roots of capsicum. Optimized experiments showed that the optimum constituents for the medium were glucose 12.0g, ammonium sulfate 2.0g, NaCl4.0g, KH₂PO₄ 3.0g. when Bacillus subtilis inoculation quantity was 2%, temperature as 25℃,pH value as 7.0,and 42h fermentation time operated,the optimal fermentation results could be achieved.