Breeding, Composite Mutation Of The Antagonistic Strain Against Tomato Leaf Mould And Their Biocontrol Effect In Fields

Tomato leaf mould is worldwide dsease,which is easy to imagine product contagion occurring between tomato plants. At present, Chemical control was principal measure,which give rise to serious environmental pollution.This issue has caused wide public concern. As a result, it has been a meaningful research topic for inhibiting plant disease by antagonistic strain. In this article, two antimicrobial,which YM2 and SM4 were Screened by ph.D Hu, is researched.Then we studied the antagonistic strain with identification, Composite mutation,the optimization of fermentation condition and the control efficacy of bacterial manure. The main conclusions are as follows:Acording to its morphological,Physiological and biochemical characteristies, YM2 and SM4 were Possibly identified as Bacillus. By taking the method of dish culture, through comparing the circle of inhibiting bacterium, the antibacterial function of YM2 was best and bacteriostasis circle has the diameter of 18.7mm and provided 100% inhibition of spore germination in tomato leaf mould. Generally speaking, YM2 have more stronger antagonism than SM4.In order to enhance the inhibitory effect of the SM4,He-Ne and LiCL were used. A new strain named L8 was formed. Antagonism of L8 has been markedly improved(14%).Genetic stability test of L8 indicated that it had a better inhibiting action after subcultured.To find out the appropriate cultural conditions for the growth and for the maximum production of antagonistic substance. The fermentation conditions and medium component of strain YM2 and L8 were studied. The results were YPF-Ga is selectioned as primary cultured. The orthogonal experimental of L16(4)5 was designed.According to results of range analysis and variance analysis, the optimal fermentation conditions are B3A2E3C3D3. Make biofertilizer containing BFA(biotechnology fulvic acid) combine reasonably with compound antagonistie agents to Produce tomato leaf mould disease specific bioehemical fulvie acid compound mierobial fertilizer. Field experimengt results show that the compound microbial fertilizer can effectively control tomato leaf mould. Compared with the contral group, the average reducing sugar, Vc, organic acid and Lycopene have been inereased.