Epidemiological studies on Blackberry chlorotic ringspot virus
B. POUDEL (1), A. G. Laney (1), I. E. Tzanetakis (1)
(1) University of Arkansas, Fayetteville, AR, U.S.A.
Phytopathology 101:S145

Blackberry yellow vein (BYV) has emerged as an important disease in all the blackberry growing areas of southeastern United States, with new viruses associated with the disease discovered continually. Blackberry chlorotic ringspot virus (BCRV), a recently identified ilarvirus, has frequently been detected in diseased samples. Other than blackberry, the virus also infects rose and raspberry making its survival more efficient. Apart from the apparent growing invasion of BCRV in blackberry and rose, there is no information on the epidemiology of this virus. The objective of this study is to acquire information on different aspects of the virus epidemiology including identification of initial sources of infection, alternate hosts and virus transmission. Several isolates of the virus infecting cultivated and wild-blackberry, raspberry and rose were collected from several states. The complete RNA 3 of the virus was amplified, cloned, and subjected to sequence analysis to determine isolate variability. Alternate host identification was performed by testing plant species present in areas with high BCRV incidence. BCRV was grafted on to herbaceous hosts and seed transmission evaluated an efficient transmission mode of ilarviruses. Rosa multiflora seeds, naturally infected with BCRV, were also collected and tested for seed transmission. The results of this study clarify factors contributing the epidemiology of BCRV by identifying the virus variability, alternate hosts and seed transmissibility.