Advances in research on maize lethal necrosis, a devastating viral disease

Maize lethal necrosis (MLN) is a devastating disease of maize caused by synergistic infection with maize chlorotic mottle virus (MCMV) and at least one potyvirid (e.g., sugarcane mosaic virus, SCMV). MLN results in leaf necrosis, premature aging, and even whole plant death and can cause up to 100% losses in yield. MLN has emerged worldwide and resulted in serious loss in maize production. Over the past decade, extensive research has been conducted to understand the epidemic and pathogenic mechanisms of MLN. In this review, we summarize recent findings in understanding the biological functions of proteins from both viruses and discuss recent advances in molecular plant-virus interactions, particularly the co-evolutionary arms race between maize anti-viral defense and viral pathogenesis (counter-defense). Based on recent research progress, we discuss how to combine different strategies for enhancing the effectiveness of maize resistance to MCMV/SCMV, and the possible approaches for effective control of MLN.