An overview of the mode of transmission, host plants and methods of detection of rice yellow mottle virus

Investigations on the mode of transmission of rice yellow mottle virus (RYM V) revealed that it is located in the rice husks. It is therefore, not tran smitted through rice seeds. The virus was transmitted through leaf debris, empty rice spikelets, intertwining roots, leaf contact, rice stubble, conta minated hands and from closely spaced plants. Chrysomelid beetles, Chnootri ba similis Thurnberg (Coccinelidae) and some long homed grasshoppers transm itted RYMV. The virus is not transmitted by nematodes, Oryza sativa L., O. glaberrima, and O. barthii are systemic hosts while O. longistaminata and a few weed species are local lesion hosts. The virus was readily detected by visual assessment based on the standard evaluation system (SES) and a sero logical test utilising enzyme linked immunosorbent assay (ELISA) and agar g el diffusion.