Developing an Effective Southernpea and Sweet corn Intercrop System

Southernpea and sweet corn can be intercropped effectively. When simultaneously planted, sweet corn appears to be the dominant crop in the mixture, with intercropped southernpea producing a supplemental yield to intercropped sweet corn. Increasing intercrop plant densities increased the amount of sweet corn yield and reduced the amount of southernpea yield. The reduction in light intercepted by southernpea and sweet corn in the intercrop situation probably contributed to the reduction in yield by these component crops as compared to the yield of these crops as monocrops. The total system LER (LER southernpea + LER sweetcorn ) for the high-population intercropping system, where plant densities for each crop were comparable to the densities of these crops as monocrops, was 1.26. This suggests that intercropping southernpea and sweet corn at this density gave a yield advantage of 26%, or that 26% more land planted in equal proportion of each component crop would be required to produce the same yield as the intercrop. A N application rate of 125 lb/acre (140 kg·ha -1 ) was optimum for intercropped sweet corn, and there was no advantage of a 2-week delayed planting of sweet corn in this intercrop system.