Biocontrol And Molecular Diagnosis Of Fusarium Solani

The elm is an important greening tree species and afforestation species in northern china, and plays a huge ecological role in sand-fixation and erosion prevention. In recent years, great economic losses and ecological damages have been caused by the banded elm bark beetle. There are no effective and environmentally harmonious methods to control it as yet. Therefore, looking for the non-pollution measures to prevent and control the plant diseases, screening and developing new microbial fungicides for Fusarium solani is very important.In this study, we collected the diseased elms attaeked by Scolytus schevyrewi in Xinjiang Urumqi and Heilongjiang Harbin and attempted to isolate antagonistic microbe that can contain F. solani, and study on its identification, antimicrobial activity of fermentation broth and optimization of its fermentation conditions for optimal inhibitory effects. In addition, with the specific primers designed, through the nested PCR amplification established a set of F. solani is fast detection technology.1. From the collected elms, microbes were isolated using the traditional microorganism isolation methods. F. solani was used as plant pathogen to test the resistance ability of the isolated microorganism with slide cultivation method, among which three strains showed interested features. Fermentation broth filtrate rescreening resistance ability screening eventually identified one optimum. JN1, from the three screened strains.JN1 mostly retarded the growth of F. solani, mold with the respective suppressing rates as 53.4%.2. Combined with related papers, the evidence from the cultural performances, morphological characteristics, physiological and biochemical features and the sequencing and analysis of its 16S rDNA of JN1 strain, we initially define JN1 is Bacillus methylotrophicus.3. Fermentation condition optimization was carried out using single factor and orthogonal tests. The results showed that the basic culture medium for JN1 is, and it grows well with initial pH was 7.0, fermentation time was 54h, cultivation temperature was 28 ℃, and rotate speed was 180 r/min.4. Based on differences in ITS sequences of F. solani and other dominant species of fungi assoeiated with S. schevyrewi, a pair of species-specific primers, Fsal/Fsa2 was synthesized. The ITS-PCR molecular detection for the tested strains have detected by specific primers Fsal/Fsa2. The results showed that, DNA extracted from Fusarium solani strain provided a single 500bp amplicon, but DNA extracted from other stains did not amplify using these primers. In the study, the sensitivity of specific primers Fsal/Fsa2 had examined, indicating that the primers sensitivity for genomic DNA detection is on the level of 1 fg/μL.