Role of Potyviruses in Synergistic Interaction Leading to Maize Lethal Necrotic Disease on Maize

Abstract

Synergistic interactions among pathogenic viruses are common in plants. Though not all, but a number of reported cases involving such interactions have a potyvirus partner during co-infection. The presence of the potyvirus group seems to favor its own multiplication on host and multiplication of a co-infecting partner. In this review, some characteristics favoring higher pathogenesis have been discussed using maize lethal necrosis (MLN)- causing viruses namely Maize chlorotic mottle virus (MCMV) and its synergistic potyvirus, Sugarcane mosaic virus (SCMV). A comprehensive discussion on the role of potyvirus in the synergism has been presented to show that in MLN and similar synergisms - the machinery for induction, transmission and colonization of the host is catalysed by the potyvirus and not the co-infecting viral partner which otherwise seems to be the most virulent in the synergism-based diseases such as MLN disease in maize. Furthermore, the effect of MLN to food security and areas for future research for Africa has been discussed in this review.