Biological characteristics of tomato mild mottle virus a potyvirus isolated from tomato and thorn apple in Ethiopia

摘要

Two isolates of the virus 246/94 and 277/94, acquired from thorn apple (Datura stramonium) and tomato (Lycopersicon lycopersicum (L.) Karst. Ex. Farw., syn. esculentum), respectively, were characterised biologically and serologically and compared with a local isolate of Potato virus Y (PVY) isolated from tomato and other potyviruses and isolates infecting vegetables. Both isolates of TMMV infected only 16 of 28 plant species inoculated mechanically and induced indistinguishable symptoms. The most susceptible hosts were D. metel, D. stramonium and Nicotiana glutinosa L. However, these isolates differed from the PVY isolate by infecting Datura spp. and Solanum demissum L., while the PVY isolate infected Chenopodium quinoa Wild and Capsicum annuum L.Isolate 277/94 was transmitted non-persistently by the aphid, Myzus persicae Sulz. from diseased tomato to virus-free D. stramonium, D. metel L., N. glutinosa and tomato plants and from these back to virus-free test plants of each species. Purified particles of isolate 277/94 contained a single protein species with a molecular weight of 39 kDa. Furthermore, in double antibody sandwich enzyme-linked immunosorbent assay (DAS-ELISA) antiserum to isolate 277/94 reacted strongly with a Yemeni isolate of TMMV (Y90/7), but did not react with any other potyvirus. This clearly shows that the Yemeni and Ethiopian isolates of TMMV are similar serologically.