Serological Studies on Host Range of Rice Virus Diseases

Abstract

The two serological techniques which are commonly used in rice virus research are Enzyme-Linked Immunosorbent Assay (ELISA) and Latex Agglutination Test (LA). These techniques were utilized to study host ranges of rice tungro virus (RTV) and Latex Agglutination Test (LA). these techniques were utilized to study host ranges of rice tungro virus (TRV) and rice raged stunt virus (RRSV). Twelve weed species, 39 wild rice species, barley, wheat and corn were artificially inoculated with viruliferous insect, Nephotettix virescens, for RTV which composed of rice tungo bacilliform virus (RTBV) and rice tungro spherical virus (RTSV) and with viruliferous insect, Nilaparvata lugens, for RRSV. Thirty days after inoculation, the second leaves from inoculated plants wee collected and homoginized with 0.02 M Phosphate buffer pH 7.2 for ELISA test and with 0.02 M Tris- HCI pH 7.4 for LA test. ELISA technique was employed to detect RRSV. Thirty days after inoculation, the scond leaves from inoculated plants were collected plants were collected and homoginized with 0.02 M Phosphate buffer pH 7.2 for ELISA test and with 0.02 M Tris- HCI pH 7.4 for LA test. ELISA technique was employed to detect RRSV in Aall the species of tested plahts while LA and ELISA were used in RTBVand RTSV detection from wild rice and weeds species respectively. The result showed that Ischaemum rugosum, Echinochloa crussgali, Leptochloa chinensis and corn contained solely RTSV wheras all wild rice sepcies tested excepted Oryzae redleyi contained both RTBV and RTSV. six weed species named Monochoria vaginalis, M. vaginalis var. plantaginea, Digitaria adscendens, Chloris barbata, Echinocholoa cruss-gali and Leptochloa chinensis were found as hosts of RRSV including corn, barley and wheat. RRSV could not be detected from O. officinalis whereas all other species of wild rice gave positive reaction in ELISA.