Study On Preservation Method And Strains Variation Of Soybean Mosaic Virus In Soybean Production Areas In Anhui Province

Soybean mosaic virus disease is one of diseases in soybean production worldwide. It causes yield loss and seed quality deficiency seriously. Collection, preservation and strains identification of the Soybean Mosaic Virus (SMV) are not only the basis of the virus itself research, but also provide the basis for resistance breeding. SMV isolates were accidentally lossed, contaminated, mixed and variation of SMV often happened during the long term storage and propagation. In addition, the propagation and inoculation of host plants are laborious time and money-consuming. In addition, Wangxiuqiang et al had identificated strains of SMV in the Huang-huai region including Anhui province. As time went on and soybean variety alternatived, the SMV strain have probably changed. Therefore, the objective of this paper is to study different preservation methods of SMV, and to investigate variation of SMV strain in soybean production areas in Anhui province. The main results were as follows:(1)Study of homiontherm, low temperature and low temperature freezer preservation methodsAt 25℃,30℃,35℃, activity of SMV could maintain five to six days in fresh lieves, and in dry treated leaves, activity kept eight to nine days. At 4℃, in fresh and dry leaves preservated 13 and 15 days respectively. The SMV infectivity was about 40%. Compareing of preservation effect at -20℃,-40℃,-80℃and -196℃showed that at -80℃and -196℃, the SMV infectivity was more than 80% in fifteen months. It could be used in long term preservation of SMV. The results also showed that preservation effect in dry leaves treatment were better than in fresh leaves at -20℃,-40℃,-80℃.(2)Study of tissue culture method for the preservation of SMVLeaves of Nannong1138-2 inoculated with SMV were employed as the source of explants for initiation of callus cultures. The results show that the infected soybean leaves can callus cultures on MS medium. In fifteen and twenty five days, infectivity of SMV was 100% on soybean inoculated with callus. The suitable concentration of NAA and BA was 0.2mgl-1and 2.0mgl-1 respectively in MS medium.(3)Investigate the SMV strain variation of soybean production areas in Anhui province.208 leaf specimens were collected from 14 counties of Anhui provinces.20 SMV isolates were obtained after biological purification with single lesion isolation and serological. Reactions of SMV isolates on 10 soybean differentials (Nannong1138-2, Youbian 30,8101, Tie feng 25, Davis, Buffalo, Zaoshul8, Kwanggyo, QihuangNo.1 and KefengNo.1). The results showed that percent of SC3, SC7 and SC8 were 20%,30% and 10% respectively. We infered that variation of composition of the strains was insignificant in Anhui provinces...