Serological Monitoring of Rice Tungro Disease Development in the Field: Its Implication in Disease Management. E. R. Tiongco, International Rice Research Institute, P. O. Box 933, Manila, Philippines. R. C. Cabunagan, Z. M. Flores, H. Hibino, and H. Koganezawa. International Rice Research Institute, P. O. Box 933, Manila, Philippines. Plant Dis. 77:877-882. Accepted for publication 10 March 1993. Copyright 1993 The American Phytopathological Society. DOI: 10.1094/PD-77-0877.

Rice tungro bacilliform virus (RTBV) and rice tungro spherical virus (RTSV) were monitored in transplanted rice (Oryza sativa) by latex test or by enzyme-linked immunosorbent assay (ELISA). RTSV was detected 1 wk after transplanting, and the incidence increased rapidly within 2–3 wk. Dual infection by RTBV and RTSV was detected 2 wk after transplanting. The infectivity of leafhoppers collected in the field corresponded with the disease development. However, the development of the tungro disease differed in cultivars with vector resistance and in different planting seasons. The main tungro infection occurred after transplanting, based on the results of covering plants with mesh screens, setting up an unprotected nursery in a tungro-affected field, and treating with insecticide at different growth stages of rice.