| Melon wilt is a soil borne disease which seriously threatens the production of melon and has caused serious agricultural economic losses. At the same time, the improper use of chemical agents, not only reduce the control effect of Melon wilt, but also bring serious damage to the environment. Because biocontrol is advantageous to human and animal safety as well as friendly to environment, so it has caused the concern among the researchers in the world. Trichoderma is currently the most common application of biocontrol agents, but biocontrol active is easy to be affected by environment. Therefore, the problem that to improve the ability of Trichoderma resisting adversity and select the appropriate synergistic factors to improve the biocontrol activity of Trichoderma must be solved. Biochar has potential effects of in soil improvement, greenhouse gas emissions, disease control and environmental governance. In order to obtain the synergistic factor of Trichoderma preparation and provide the basis for the improvement of Trichoderma preparation technology, the effect of carbon source on the hyphae growth, biocontol activity and gene transcription difference of Trichoderma were studied.1. Effect of different carbon sources on the growth and bio-control activity of Trichoderma were studied. The results the study showed that, the utiliz of Trichoderma to single carbon source, such as biochar, glucose, lactose, starch, hymexazol and compound carbon source of biochar with glucose, lactose, starch were significantly different. Among the single carbon sources, when the glucose was used as the carbon source, the growth of T23,T56 and T27 were best, but T27 growed best with lactose as the carbon source. The second days of growth diameter were 75.3 mm,79.2 mm,50 mm,58 mm. However, the effect of biochar on the growth of the mycelium was not obvious, and the growth was inhibited by the hymexazol. The spore production of T23, T56, T20 and T27 were reach the highest, when glucose as carbon source, respectively as 17×107 spores/mL,16.15×l07 spores/mL,12.57×l07 spores/mL,16.75×l07 spores/mL, and the hymexazol inhibited spore production, biochar as carbon source was compared with the CK group, the difference was not significant. T23 and T56 with glucose as carbon source, and T20,T27 with lactose as carbon source, mycelial dry weight increased significantly, respectively 0.21 g,0.24 g,0.26 g,0.25 g. Biochar and hymexazol were no significant effect on the mycelial dry weight. In biocontrol activity of the four strains, when glucose as carbon source, were the strongest. The activity of Trichoderma were low with biochar as carbon source. Compared with the CK group, hymexazol can enhance the ability of T56 inhibition. In enzyme activity, four strains of Trichoderma with glucose as carbon source, the production of cellulase and β-1,3-glucanase activity reched highest, T20,T23,T56 with lactose and T27 with glucose as carbon source, the producing chitinase activity were highest. In the compound carbon source, the mycelium growth, dry weight and biocontrol activity of Trichoderma reached the highest and higher than 4.0%～ 90.00%compared with the optimal single carbon source data. Just like the complexed with biochar and glucose, the biochar could also improve the use of Trichoderma on lactose, starch, glucose to a certain extent. The compound of biochar and glucose as carbon source compared with glucose, the chitinase and β-1,3-glucanase activity of the four strains of Trichoderma were high 1U/mL～10U/mL, the cellulase activity of T23 and T56 were high 121.73U/mL,55.46U/mL. The cellulase activity of T27 and T20 reached the highest with the compound of biochar and lactose as carbon source, respectively for 273.32U/mL, 267.45U/mL, but lower than glucose.2. Effects of biochar on shelf life of Trichoderma and Fusarium Wilt of melon.The results of the shelf experiment showed that the early and late stage growth diameter of the spore storage differ by 20 mm with the biochar as stroma, while the growth diameter differ by 34 mm with the soil as stroma. Obviously the biochar could prolong the shelf-life of Trichoderma spore. The results of pot experiment showed that the biochar group was compared with ck group, the germination rate of melon seeds was high 15%, seedling was high 27 mm, melon incidence decreased by 17%. The roots of melon seedlings were only injected of pathogenic bacteria, the incidence rate of the melon in the Biochar group was decreased by 4.44%, and The roots of melon seedlings were injected of pathogenic bacteria and Trichoderma, the control effect of the biochar groups were high 7%～22%.3. Analysis of the difference of the transcriptional groups of the biochar to the Trichoderma. The transcriptome of TCK and TIN two samples of the T23 were sequenced by Hiseq2000 high throughput sequencing technology. Then the original data were filtered and splicing, and finally obtained 25044 Transcript sequences. Finally, through the blast reference protein library (NR) results obtained 11125 unigene. All-unigene were compared with Swiss-prot, NOG and KEGG public protein database, genes were classified by GO annotation and understood gene metabolic pathway by KEGG annotation. There are 7870 genes obtained GO annotation among All-unigene. There are 3105 (27.91%) transcript sequences were comparison to the KEGG database,122 KEGG metabolic pathways were obtained. Through the comparative analysis of TCK and TIN transcription groups, there were 333 differentially expressed genes, including 153 up regulated genes and 180 down regulated genes. GO enrichment analysis of differentially expressed genes showed that enrichment expression of oxidoreductase activity was the most remarkable, the next was biological process. KEGG enrichment analysis showed that all the annotated differentially expressed genes excepted the ribosomal translation pathway accounted for 10.47% of the KEGG annotated sequences, the others mainly involved in carbohydrate metabolism, carbon metabolism, amino acid metabolism, xenobiotics biodegradation and metabolism. Through SNP analysis,2211 SNP polymorphic loci were obtained in the TCK samples, and 2350 polymorphic SNP loci were detected in the TIN samples. Through SSR prediction of the All-unigene sequence, acquired 3741. |
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