Transmission of capsicum chlorosis virus by Thrips palmi(Thysanoptera: Thripidae)

Transmission efficiencies of capsicum chlorosis virus (CaCV) were investigated for four thrips species (Thysanoptera: Thripidae), Frankliniella occidentalis(Pergande), Frankliniella intonsa(Trybom), Thrips palmi(Karny), and Thrips tabaciLindeman infesting green pepper in Japan. The first-instar larvae of the thrips were allowed to feed on CaCV-infected green pepper leaves for 24 h. The transmission of CaCV by thrips was examined using a petunia leaf disk assay. CaCV was transmitted by four male (8.70%) and four female (3.88%) T. palmi, but the virus was not transmitted by adults of any other species. In a second transmission assay, 10 adult T. palmithat had fed on infected leaves as larvae were released to healthy green pepper seedlings. After 21 days, the seedlings were examined and 50% of them showed symptoms of CaCV infection. RT-PCR confirmed that they were infected with the virus. The viruliferous rate of adult T. palmiwas 60%, while CaCV was not detected in adults of the other three species. These results suggest that T. palmiis capable of being a new vector of CaCV.