Study And Application Of New Efficient Anti Tobacco Mosaic Virus Preparations

Plant diseases and insect pests are major factors to impede plant growth. Measures are exerted in production to prevent this virus disease while their effects are hardly ideal. In that case, it is of practical significance toexplore and select effective preparations and application methods to prevent plant diseases. Aminobutyric acid (BABA), a non protein amino acid in plants’secondary metabolism plays a key role in resisting both biotic stress and abiotic stress of plants; Ningnanmycin, amino Oligosaccharin and Dongwangduxiao are anti-viral preparations generally used in agricultural production. Accordingly, this research taking tobacco (Yunyan 97) as materials, aims of innovative highly-effective preparations by compounding 5mmol/L BABA with 8% Ningnanmycin,2% amino Oligosaccharin and Dongwangduxiao respectively to protect its ability in resisting tobacco mosaic virus (TMV). At the meantime, application trials are taken on representative tobacco fields in South Anhui.The inhibition rate and the incidence rate of Yunyan 97 in response to TMV under the condition of those three new compound preparations were studied in both the laboratory and natural field. The results showed that all three preparations can reduce the incidence of TMV. In the laboratory, we studied the resistance physiology and mechanism induced by the new preparations. Elisa kit measured the content of salicylic acid (SA) in leaves; histochemistry method measured the anaphylactic reaction induced by those new preparations and detected PAL activity; and qRT-PCR detected the gene expression of related protein-PR protein. The results suggested that the three new compound preparations could significantly increase the content of SA in leaves, cause anaphylactic response, improve the activity of PAL, and induce the gene expression of PR1 and PR3. The DAB histochemical allocation and quantitive analysis of H2O2 s-how that the new preparations could obviously induce oxygen to burst while significantly improve the CAT activity. All the results suggest that three new compound preparations induce the protection effect of anti-oxidase system and enhance tobacco’s ability to resist TMV.In the field experiments, we measured the initial infection of TMV in soil, stroma and water, and the result showed that TMV were not found. Then we measured the leaves of tobacco at seedling stage, and the result suggested only few of them were infected with TMV. We also sampled and measured the leaves at their growing and maturing stage respectively, and the result showed that the testing rate of TMV were restrained after using the new preparations while the incidence of a disease and the disease index were both at low level, the control effect is at high level,indicating the new compound preparations can effectively enhance the tobacco’s ability to resist the infection of TMV in the fields.In conclusion, the results show that three new compound preparations can effectively improve the tobacco’s resistance ability to TMV and the effect of using three together is better than that of using only one of them.Particularly, among them, compounding 5mmol/LBABA with 8% Ningnanmycin effects the best.