Association of a badnavirus in black pepper (Piper nigrum L.) transmitted by mealybug (Ferrisia virgata) in India

The association of a badnavirus with disease-affected black pepper leaf samples collected from Kozhikode (Calicut) and Wyanad districts of Kerala was established on the basis of symptomatology, vector transmission, electron microscopy and serology. The virus induces vein clearing, chlorotic flecks, chlorotic mottling along veins and characteristic curling of leaves leading to reduced vigour and yield. The virus was transmitted from diseased to healthy black pepper plants by grafting and mealybug (Ferrisia virgata). The virus could also be transmitted by mechanical means with difficulty to black pepper, but not to other hosts tested. The virus showed positive serological relationship with Banana streak virus (BSV) and Sugarcane bacilliform virus (ScBV) in direct antigen-coated enzyme-linked immunoassay (DAC-ELISA) using polyclonal antisera. The exact taxonomic identity of the virus remains to be determined.