Occurrence of coffee ringspot virus, a Brevipalpus miteborne virus in coffee in Costa Rica.
In August 2000, severe symptoms of concentric ringspots and "oak leaf" patterns on coffee (Coffea arabica cv. Catuai) leaves were observed during field inspections conducted in two areas of San Gabriel de Desamparados, Costa Rica. The disease caused premature fruit and leaf drop in the affected plants. Some areas with the ringspot lesions remained green on senescent leaves. Leaves with symptoms were collected and examined by transmission electron microscopy. In ultrathin section of symptomatic leaves, arrays of rhabdovirus-like particles were associated with the nucleus as described for coffee ringspot virus (CoRSV). Twenty mites collected from the infected plants at the same locations and time were slide-mounted and identified as Brevipalpus phoenicis. This is thought to be the first report of a virus similar to CoRSV in Costa Rica.