EFFECTS OF ARTICHOKE LATENT VIRUS AND BROAD BEAN WILT VIRUS ISOLATE FA ON COMPONENTS OF GROWTH AND YIELD OF GLOBE ARTICHOKE

The effects of single and mixed artificial infections by artichoke lat ent virus (ALV) and broad bean wilt virus isolate FA (BBWV-FA) on comp onents of growth and yield of three globe artichoke lines were evaluat ed in an aphid-free glasshouse. Virus infections reduced plant vigour (length of leaves and height of the ramifications) and dry weight, inc reased dry matter percentage, lengthened harvest period, and induced s ignificant losses in the number of harvested buds, which resulted from reduced production of ramifications. However, the magnitude of affect ed parameters depended on inherent line differences and the type of vi rus infection. The greatest reductions occurred with the ALV + BBWV-FA infection. In single infections ALV led to the more severe effects, e specially on components of yield. The level of ALV coat protein, as de termined by ELISA, indicated differences in titre between plants of th ree lines. Cari line, which exhibited greater yield reduction than Cad a or CBT lines, had the higher ALV virus titre. Conversely Cari was le ss susceptible to BBWV-FA infection than Cada. The detrimental effects of virus infection emphasize the need for virus control, and differen ces in responses among lines indicate the possibility of control by pl ant breeding.