EFFECTS OF TOMATO RINGSPOT VIRUS ON THE GROWTH AND YIELD OF RED RASPBERRY

Abstract

Tomato ringspot virus (TomRSV) was graft-inoculated into 10 raspberry (Rubus idaeus L.) cultivars in 1970 and plants of root cuttings from infected and virus-free (VF) plants were established in the field in 1971. Data were recorded on the growth of the newly propagated plants in 1971 and on growth and yield in 1972, 1973 and 1974. TomRSV infection resulted in retarding the growth of the young plants arising from the root cuttings of 8 of the 10 cultivars. Chlorotic ringspot markings were evident on many of the young plants arising from the root cuttings, but in subsequent years very few foliar markings were observed. A year after the plants were established, the canes of six cultivars were shorter than those of VF clones. The cultivars Avon, Latham, Lloyd George, and Mailing Jewel had significantly shorter canes in each of the 3 yr that measurements were taken. Only two cultivars, Carnival and Lloyd George, showed a reduction in yield in the 1st cropping year. By the 3rd cropping year, Avon, Glen Clova, Latham, Lloyd George and Meeker all showed a significant reduction in yield. Avon and Lloyd George also showed reduced fruit size. When all growth parameters were considered, the cultivar ranking in order of decreasing susceptibility was as follows: Lloyd George, Avon, Latham, Glen Clova, Meeker, Matsqui, Mailing Jewel, Carnival, Puyallup, and Canby.