Innovative corn-legume intercropping: a strategy to suppress insect pest occurrence

Intercropping corn-legumes increase food production per unit of land via better utilization of resources, minimizes the occurrence of insect pests, reduced weed competition and stabilize yield. This study was conducted to determine the significant effects of intercropping corn with legumes in terms of yield and yield component, population density of insect pests and compare the yield of sole corn with intercrop with legumes. A RCBD [randomized complete block design] with seven treatments replicated three times was used as follows: Treatment 1 = sole corn, Treatment 2 = corn + peanut, Treatment 3 = corn + bush sitao, Treatment 4 = corn + snap bean, Treatment 5 = sole bush sitao, Treatment 6 = sole peanut, Treatment 7 = sole snap bean. Results showed that planting of sole corn at 30, 60 and 90 DAP produced the tallest plant height, heaviest biomass yield, wider diameter of corn ear and heaviest weight of 1000 seeds. Planting of sole legumes revealed significant variation in terms of shoot length, number of pods and grain yield per hectare. At 20, 30 and 40 DAP, a lower number of insect pests, lowest damage of insect pest and higher number of beneficial insects observed at intercrops of corn + peanut (T2). In like manner, the damage rating on corn at 35 and 45 DAP revealed significant difference among treatments. The grain yield per hectare was heavier in the sole corn, however, when the Land Equivalent Ratio was considered it showed higher values and higher productivity advantage of intercropping system over sole corn. Adoption of intercropping system, corn + peanut should be considered because lesser damage of borer in corn was observed. Further studies on intercropping should be conducted using the other crops that are compatible to reduce occurrence of insect pests and diseases.