Selection of an attenuated strain of Japanese yam mosaic virus and its use for protecting yam plants against severe strains

Abstract

An attenuated strain of Japanese yam mosaic virus, selected from the fields and referred to as JYMV-M, caused no symptoms on Japanese yam plants throughout the growing season. The purified virus preparation was highly infective, and the virus was easily transmitted by aphids. An RT-PCR-RFLP assay was used in cross-protection tests to discriminate JYMV-M from other severe strains. Pre-inoculation of yam plants with JYMV-M remarkably protected them from infection with severe strains. JYMV-M infection did not affect either the quality and quantity of yam production.