Bud necrosis of groundnut (Arachis hypogaea) in India caused by tomato spotted wilt virus*

Chlorotic ringspots or chlorotic leaf specking, terminal bud necrosis, axillary shoot proliferation and severe stunting of groundnut (Arachis hypogaea) were shown to be caused by tomato spotted wilt virus (TSWV). Cowpea (Vigna unguiculata cv. C-152) was found to be a good assay host. TSWV remained infective in buffered sap of groundnut at a dilution of 10-2’5, after storage for 4 h at room temperature (30 “C) and for 10 min at 40 but not 45 OC. The haemagglutination test was adapted to detect TSWV in crude extracts of groundnut. Sap from infected groundnut and tomato contained spherical membranebound virus particles 70 to 90 nm diameter. The virus was transmitted by thrips (Scirtothrips dorsalis). The prevalence of TSWV in India and the high incidence in groundnut indicates that the virus is economically important. All 28 species of plants tested were susceptible to the virus.