ASSOCIATION OF RHODOCOCCUS (CORYNEBACTERIUM) FASCIANS WITH THE STUNTING-FASCIATION SYNDROME OF CARNATION IN ISRAEL

A disease causing stunting of plants and fasciation and deformation of flowers has been found in Israel in several locations since 1985. Symptoms resemble “mal del prezzemolo” found in Italy.
Attempts to transmit the disease mechanically to carnations or to a spectrum of herbaceous test plants were not successful.
Similarly, no transmissions were obtained, when more than 60 carnation plants were grafted with diseases scions.
When symptomatic plants were transferred from the growers greenhouse to Bet Dagan, symptoms at first disappeared, but later strong symptoms were again observed.
An additional cycle of symptom remission and appearance was observed.

From symptomatic plants a gram positive non-motile bacterium was consistently isolated on nutrient-glucose agar and Kado & Hesketts D-2 selective medium.
Yellow-orange colonies were tentatively identified as Rhodococcus (Corynebacterium) fascians.
Antisera were prepared against fixed and living cells of an identified strain of R, fascians (obtained from Germany) and against a local isolate from carnations.
An indirect immunofluorescence (IF) assay was developed which was used to screen carnation plants.
High correlations were obtained between the IF assay and disease symptoms, with the 2 antisera.
These results suggest that R. fascians is involved in the fasciation disease of carnation.

VIII International Symposium on Virus Diseases of Ornamental Plants

D. Zutra, J. Cohen, A. Gera, G. Loebenstein

https://doi.org/10.17660/ActaHortic.1994.377.34