ABSTRACT

Cowpea (Vigna unguiculata L. Waip) is an important grain legume in Nigeria. It is an inexpensive source of vegetable protein. Cowpea production in Nigeria is largely constrained by insect pests. Field studies were conducted for two cropping seasons in Umudike Nigeria to determine the effect of cowpea-turmeric intercrop on field insect pests of cowpea. The experiment was laid out in a Randomized Complete Block Design (RCBD) using ten treatments with three replications. During the experiment, turmeric was intercropped with two varieties of cowpea (IT89KD-391 and IT86D-719) which was planted 5 weeks after the turmeric had sprouted. Fowl droppings were incorporated into the soil after the beds were made. Results obtained showed no significant difference in leaf area in all the crop mixtures. There was also no significant difference in cowpea plant height. However the IT89KD-391 intercropped with turmeric showed significantly higher plant height (56.6) when compared with the sole turmeric which recorded 42.5. Result obtained indicated that intercrop had significant decrease on the population of Aphis craccivora and Riptortus dentipes at 5% level of probability. The effect and damage by these two pests was highly reduced in the intercrop while it was increased in the sole crop and the cowpea mixtures. Jntercropping reduced the Megalurothrips sjostedti population in the first season of the first year ut the reverse was the case in the subsequent seasons. Result generally showed that pest abundance was more during the long rains than the short rains. The yield of the cowpea was significantly higher in the intercrop (IT89KD-391 inter row weighed 610 kg/ha, while IT 86 D-719 inter row weighed 560.4kg/ha) However, it was low in the sole crop (IT89KD -391weighed 420.8kg1ha and IT86D-719 weighed 402.kg/ha). Similar result was also obtained in the second year. The two cowpea mixture supported the highest level of pest population and damage among all the cropping combinations.