Performance of Okra (Abelmoschus esculentus L.) and Maize (Zea mays) under Okra/Maize Intercrop as Influenced by Nutrient Sources at Ibadan, Nigeria

Abstract

Farmers' practice of planting more than one crop under mixed cropping without fertilizer application has been a source of concern in Nigerian agriculture due to inherent low fertility status and fragile nature of the soils. This study was set up to assess the performance of okra (Abelmoschus esculentus L.) and maize (Zea mays) under okra/maize intercrop as influenced by nutrient sources at Ibadan, Nigeria Okra (Abelmoschus esculentus L.) and maize (Zea mays) were each sown as sole and in mixed crop at 1, 2 and 3 seeds hole-1. Fertilizers were used as organic {kola (Kola nitida) pod husks, KPH} applied at 5 and 10 t ha-1 and inorganic (NPK) applied at 80 and 160 kg N ha-1 and control The field experiment was conducted in randomized complete block design with three replicates at Ibadan, Nigeria on 30 April, 2010 for early cropping and 15 August, 2010 for late cropping season. Data obtained included okra plant height, girth, fruit yield and grain yield for maize. The land equivalent ratio (LER), aggressivity and monetary value (MV) were calculated. Okra plant height, girth, fruit and maize grain yield values were significantly higher in sole than in mixed cropping in both early and late cropping seasons. The fertilizers resulted in significantly higher okra performances compared to the control during both cropping seasons. The NPK fertilizer reduced okra yields in the late season compared to the early season, while it increased for KPH fertilizer. Maize grain yield in both seasons was in similar trend to that obtained for okra fruit yield. Planting okra and maize in mixture at 2 plants stand-1resulted to LER values that were generally greater than unity and resulted to 5.7-45-7% of land area saved, with low level of aggressivity and higher monetary value (MV) compared with sole maize and okra. The use of 2-plants stand-1 was optimum for better performance of okra and maize either planted sole or as okra/maize intercrop, while KPH @ 5 tons ha-1 and NPK @ 80 kg N ha-1 were optimal rates for better growth and yield of okra and maize both in monoculture and intercrops.