Coriander: A New Natural Host of Groundnut Ring Spot Virus in Brazil.

Coriander plants (Coriandrum sativum L. 'Palmeira'), showing stunting, chlorotic ring spots, necrosis, and malformation of apical leaves were observed on 50-day-old-plants in July 1998 in one seed production field at Petrolina, State of Pernambuco, Brazil, but not in nearby fields. Leaf samples were collected and tested by double antibody sandwich-enzyme-linked immunosorbent assay (DAS-ELISA) with a panel of polyclonal antibodies made against the nucleocapsid protein (N) of tomato spotted wilt virus (TSWV), tomato chlorotic spot virus (TCSV), groundnut ring spot virus (GRSV), and impatiens necrotic spot virus (INSV) (1). All symptomatic samples reacted only with the GRSV antisera. Coriander leaf extracts from infected plants were mechanically inoculated onto potential indicator hosts. The virus induced systemic infection with vein clearing, chlorotic and necrotic spots, necrotic ring spots, mosaic, top distortion, and stunting within 21 days after inoculation on Capsicum annuum cv. Ikeda, C. chinense PI 159236, Physalis floridana, Nicandra physaloides, Nicotiana tabacum cv. TNN, N. benthamiana, Lycopersicon esculentum cv. Rutgers, Phaseolus vulgaris cv. BT2, and Gomphrena globosa. The symptomatic indicator plants tested positive for GRSV by DAS-ELISA. P. vulgaris, Chenopodium amaranthicolor, C. quinoa, and Cucurbita pepo (zucchini) cv. Caserta showed only small, necrotic, local lesions on inoculated leaves. Citrullus lanatus cv. Charleston Gray was asymptomatic. This is the first report of natural occurrence of GRSV on coriander in Brazil. Reference: (1) A. C. de Ávila et al. J. Gen. Virol. 71:2801, 1990.