Detection of Japanese Yam Mosaic Virus from Chinese Yam (Dioscorea opposita Thunb. cv. ichoimo) by Immunocapture PCR and Differentiation of Virulent and Attenuated Isolates by PCR-RFLP Analysis

Abstract

Detection of Japanese yam mosaic potyvirus (JYMV) in Chinese yam (Dioscorea opposita Thunb. cv. ichoimo) by the immunocapture polymerase chain reaction (IC-PCR) and differentiation of virulent and attenuated isolates using restriction fragment length polymorphism (RFLP) of IC-PCR products using Tsp 509 I were investigated. JYMV was detected by IC-PCR from diseased leaves, bulbils, tubers or diseased leaves frozen at -40°C for 6 months with a sensitivity of 10⁸, 10⁵, 10⁶ and 10⁷-fold dilutions, respectively. The sensitivity of IC-PCR for the detection of JYMV from diseased leaves was about 8000-fold over ELISA and 10, 000-fold over RT-PCR. PCR-RFLP revealed different banding patterns for the virulent and attenuated isolates of JYMV. This will be useful for distinguishing virulent and attenuated isolates from Chinese yam (cv. ichoimo).