Induction of Antiviral Responses by Acibenzolar-S-Methyl Against Cucurbit chlorotic yellows virus in Melon

Abstract

Cucurbit chlorotic yellows virus (CCYV) (family Closteroviridae, genus Crinivirus) is an emerging virus which causes severe diseases on melon (Cucumis melo) plants. CCYV-infected melon plants display yellowing, mottling, chlorosis, or chlorotic spots on leaves. To develop a new control strategy, the potential for 1,2,3-benzothiadiazole-7-thiocarboxylic acid-S-methyl-ester (ASM) to suppress CCYV infection was evaluated. ASM treatment on melon plants greatly increased the expression levels of pathogenesis-related 1a gene, a marker gene for systemic acquired resistance. ASM treatment on melon plants before inoculation of CCYV suppressed systemic symptoms and decreased CCYV accumulation. ASM treatment on melon even after inoculation of CCYV reduced disease severity and accumulation levels of CCYV. The results show the potential for ASM treatment on attenuation of the CCYV disease symptoms.