First report of yambean mosaic virus infection in butterfly pea (Clitoria ternatea) in Thailand

Butterfly pea (Clitoria ternatea) plants with mottling, vein banding, blistering, and wrinkling symptoms were observed in Chiang Mai Province, Thailand, indicating potential potyvirus infection. RNA was extracted separately from three symptomatic leaf samples and immature and mature seed samples and tested by RT-PCR using degenerate primers targeting the coat protein (CP) gene of potyviruses. Four samples, excluding mature seeds, tested positive for potyvirus. Mechanical inoculation reproduced symptoms in butterfly pea, senna (Senna occidentalis), and yardlong bean (Vigna unguiculata subsp. sesquipedalis). Phylogenetic analysis confirmed the virus was yambean mosaic virus (YBMV), marking the first report of YBMV in butterfly peas and in Thailand.