Screening of Rice Accessions For Resistance to Rice Yellow Mottle Virus

Abstract

Rice yellow mottle virus (RYMV) is responsible for the most damaging virus disease of rice in Africa. The objective of this study was to assess the reaction of rice accessions to RYMV, for better control of the virus. Rice accessions including landraces and collections from research institutes were collected from 2010 to 2013 in Burkina Faso and Ghana. Two viral inoculums composed of non-resistance-breaking RYMV isolates (inoculum-1) on the one hand and of resistance-breaking isolates (inoculum-2) on the other hand were used for the screening experiments in the greenhouse. A subset of rice accessions were exposed to field isolates under field conditions of virus transmission. Experimental designs were randomized complete blocks with three replicates. Of 117 rice accessions challenged with inoculum-1, 69.2% were susceptible to RYMV and expressed disease symptoms between 10 and 13 days post-inoculation (DPI). Partial resistance