Alteration of stress-physiological mechanisms in sRNA-treated sweet corn plants during MDMV infection.

Maize dwarf mosaic virus (MDMV) can significantly reduce the growth and development of susceptible varieties of sweet corn. The virus utilises the energy and reserve sources of plant cells to ensure its reproduction in the microspaces formed by cell membranes. Therefore, the severity of stress can be monitored by examining certain physiological changes, for example, changes in the degree of membrane damage caused by lipid peroxidation, as well as changes in the amount of photosynthetic pigments. The activation of antioxidant enzymes (e.g. ascorbate peroxidase, guaiacol peroxidase, glutathione reductase) and the accumulation of phenolic compounds with antioxidant properties can indirectly protect against the oxidative stress caused by the presence of the positive orientation, single-stranded RNA-virus. This study demonstrates the changes in these physiological processes in a sweet corn hybrid (Zea mays cv. saccharata var. Honey Koern.) susceptible to MDMV infection, and suggests that exogenous small RNA treatment can mitigate the damage caused by virus infection.