Limited Systemic Spread of Impietratura and Psorosis-A in Graft-Inoculated Grapefruit Trees. M. Bar- Joseph, Virus Laboratory, Agricultural Research Organization, Volcani Center, Bet Dagan, Israel. J. Ben-Shalom, Virus Laboratory, Agricultural Research Organization, Volcani Center, Bet Dagan, Israel. Plant Dis. 66:820-821. Accepted for publication 30 December 1981. Copyright 1982 American Phytopathological Society. DOI: 10.1094/PD-66-820.

Four grapefruit trees were inoculated with impietratura-diseased buds on one or two secondary canopy branches per tree. Fruit symptoms characteristic of impietratura developed 3–6 mo after the secondary branches were inoculated. On a budded branch, symptoms were observed only near the inoculation site; even 8 yr after inoculation, affected fruits could not be found on branches originating about 1 m below the inoculation site. Indexing on indicator plants indicated the presence of inoculum causing leaf flecking symptoms only in branches originating less than 90 cm basipetally from the inoculation site and in almost all acropetal parts. Budwood from two grapefruit trees with psorosis-A showed the same infection pattern.

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