The Study on Two Virus Isolates of Beet in Xinjiang

Two virus isolates were found in beet in Xinjiang.After they are inoculated to beet the isolates induced yellow ring spot and line patterns along vein of leave.The rmgspot and line patterns eventuallyformed necrosis.The virus infected Chenopodium amaranticolor C.quinoa, Telragnia axpansa and Spinacia oleracea and induced local necrotic leeions.The virus infected Nicltiana tabacum,N. glolionosa,Pelunia hy brida,bean,cucumber and tomato but without showing symptoms.The virus particles have icosahedramorphology with an averege diameter of 28nm,In sap the virus thermal inactivation point(10min)is70℃.Infectivity is retained for 13 days at room temperatue about 20℃ and for 7 years in refrigerat ed dry leaves.The highly purified virus is easily obtained from C.amaranticolor by precipitation withPEG and differential centrifugation,Absorption spetrum of the virus is maximum in 260nm and minimum in 245nm.Protein subunits have M,W.27000.Cenome nucleic acid of the virus consists of three species with sizes of 3.08kb,1.28k