Transmission of California aster and celery-yellows virus by three species of leafhoppers

Abstract

does not appear. First page follows. Introduction It has been suggested that possibly an obligate relation exists between a specific insect vector and the aster-yellows virus, and that developmental changes and multiplication of the virus take place during the incubation period in the insect.(8) It has been assumed in the past that the aster-yellows virus could be disseminated only by the leafhopper, Cicadula divisa Uhl., which is widely distributed in America. Ogilvie(10) reported yellows of China aster (Callistephus chinensis) in Bermuda, where Cicadula sexnotata (Fall.), responsible for the transmission of the virus there, has been known to occur since 1924. The disease also occurs on cos lettuce, cabbage lettuce, eight species of ornamental flowering plants, and several wild plants in Bermuda. Fukuski(5) reported that aster yellows occurs in Japan. Kunkel(8) reported that Cicadula sexnotata occurs in Japan and probably throughout the Orient. Dobroscky3 reported that aster yellows was found in the gardens of the Budapest Experiment Station, and in the vicinity of Lake Balaton Biological Laboratory, Hungary. Cicadula sexnotata is widespread and common in Europe.(8) In California three species of leafhoppers transmit the aster-yellows virus. Cicadula divisa transmits the virus with greater efficiency than the mountain leafhopper, Thamnotettix montanus Van D. or the geminate leafhopper, T. geminatus Van D. Experiments with the leafhoppers Agallia californicum (Baker), A. cinera (O. &; B.), and Empoasca abrupta De L. bred on celery failed to transmit the yellows virus.(13)