Interactions between maize dwarf mosaic and weed interference on sweet corn

Maize dwarf mosaic (MDM) and weed interference are two economically important stresses to sweet corn; however, a fundamental understanding of the extent to which the crop is affected by combinations of these stresses is lacking. The objective of this study was to quantify the extent to which MDM incidence and weed interference influence the sweet corn canopy. phenological development, and yield. In field research, five levels of MDM incidence (0, 25%, 50%, 75%, and 100% of the plant population) were established in two sweet corn hybrids that also were grown in the presence or absence of wild-proso millet. During the vegetative phase of crop growth, the crop's ability to tolerate these multiple stresses was largely additive. For instance, incidence of MDM decreased crop growth and delayed development by as much as five days, and wild-proso millet added to those detrimental effects by an extent that was determined by the severity of weed interference. In contrast during the reproductive phase, MDM incidence and weed interference interacted in their effect on the crop. Moreover, differences in hybrid responses to the multiple stresses indicated that the benefit of improved crop tolerance to weed interference was not lost when the crop is infected with MDM. Use of hybrids with high levels of MDM resistance and improved competitive ability with weeds reduces the risk of losses from MDM and weed interference, two commonly occurring stresses in sweet corn. Published by Elsevier B.V.