Studies on the Virus Diseases of Stone Fruit

Abstract

Natural infection of plum line pattern virus was found on plum varieties Methley, Burbank, Red June, White plum, Beauty, Santa Rosa and Ooishi-wase, prune variety Hungarian and flowering cherry varieties Someiyoshino, Ranzan, Ruiran and Kwanzan.Plum line pattern virus was transmitted by budding from the diseased trees of plum and flowering cherry to seedlings of peach, plum, apricot, Japanese apricot, cherry and flowering cherry.The leaves of naturally infected trees of plum and flowering cherry showed typical yellow line pattern, yellow vein net and chlorotic ring or spot. In the case of artificial inoculation the seedlings of peach, apricot, cherry and flowering cherry showed line pattern mainly, but Japanese apricot seedlings showed line pattern, vein net as well as severe stunting.One mechanically transmissible virus was isolated from the peach seedlings inoculated with plum line pattern. This virus induced chlorotic local lesion on the inoculated leaves of cucumber, but it did not cause any symptoms on Catjang, petunia, Nicotiana glutinosa, N. megalosiphon, Chenopodium amaranticolor and C. quinoa which have been reported as hosts of plum line pattern virus by Fulton and Kirkpatrick et al.Methley isolate of plum line pattern virus and one isolate of apple mosaic virus caused same line pattern symptoms on Chaenomeles japonica. The former affected the seedlings of peach but not apple, and the later affected the seedlings of apple but not peach.