甘薯羽状斑驳病毒的分离与提纯

ISOLATION, PURIFICATION OF SWEET POTATO FEATHERY MOTTLE VIRUS

本文应用标准的甘薯羽状斑驳病毒(SPFMV)抗血清,通过两次蚜传,从徐薯—18、新大紫上得到一种病毒分离物。接种指示植物后这种分离物仅感染Ipomoea setosa、Ipomoea nil,不侵染Gomphrena globosa L.、Beta vulgaris L.、Nicotiana tabacum L.、Nicotiana glutionsa L.、Brassica pekinensis, Datura stramonium L.、Cucumis sativis L.、Brassica、juncea、Raphanus sativus、Phsalis floridana。此病毒分离物可用蚜传、摩擦接种、嫁接三种方式传播,稀释限点为10^(-5),体外存活期不到24小时,热灭活温度为60～65℃。蚜传这种分离物到 I·Setosa上,再嫁接到I. nil或I. setosa上扩大增殖,用0.2M pH7.2 PB^K进行粗提取,结合垫层超离心,最后经蔗糖密度梯度离心得到了高纯度的病毒的提纯物,OD260/280的比值为1.25,粒体长度主要集中在830～850nm之间。实验证明这种病毒分离物为甘薯羽状斑驳病毒(SPFMV)。病毒收量为64.3mg/kg感病组织。提纯病毒在电镜下任何视野都可见到多量的、密集成堆的病毒粒体。

An isolate of virus was obtained through twice transmission of aphid and identification of antiserum to SPFMV from sweet potato of Xushu-18 and Xing Dazi. This isolate infects Ipomoea setosa and Ipomoea nil, but not Gomphrena globosa L. ,Beta vulgaris L., Nicotiana tabacum L. ,Nicotiana glutinosa. L. ,Brassica pekinensis B. , Brassica juncea, Raphanus sativus, Datura stramonium. L. ,Cucumis sativis L., Physalis floridana. It is transmissible by Myzus persicae,sap and grafting. Thermal inactivation point is 60-65℃, dilution endpoint 10-5,and longevity in sap less than 24 hr. Transmitting this isolate to Ipomoea setosa by aphid first, then grafting to I. nil or I. setosa for propagation. The infected tissue was homogenized in 0. 2M pH7. 2PBK and the virus was purified by differential centrifugation with sucrose cushions and sucrose density gradient centrifugation. Highly purified virus was obtained with a 260/280 ratio of 1. 25. The purified virus particles measured approximately between 830 and 850nm in length. The results show that this virus isolate is identified to be Sweet Potato Feathery Mottle Virus (SPFMV). The virus yield of 64. 3mg/kg from fresh I. setosa tissue were obtained by the present purification procedure.