Journal of Biology, Agriculture and Healthcare www.iiste.org ISSN 2224-3208 (Paper) ISSN 2225-093X (Online) Vol.5, No.17, 2015 201 Influence of N-Fertilizer application on the yield and yield components of two varieties of eggplant (Solanum melongena L.) In Anyigba, Kogi State Umar Musa Tanko Department of Crop Production, Kogi State University, P. M. B. 1008, Anyigba, Kogi State, Nigeria. Momoh, Jimoh Yusuf Department of Crop Production, Kogi State University, P. M. B. 1008, Anyigba, Kogi State, Nigeria. Abstract There is a need to device a possible ways of improving necessary nutrients for better performance of eggplants. The use of mineral fertilizer in tropical soils can help solve the problem of low soil nutrients. So far, only N- level have been recommended in most of the region of Nigeria, the specific requirement for varieties have not or in most cases been overlooked, therefore determination of the interaction of N-level with variety is necessary as it will enable researchers determine specific level of N-fertilizer for specific variety. Thus research was conducted on Kogi State University Student Research and Demonstration Farm (Longitude 07°06 1 N; 43°E), Anyigba, Kogi State, to investigate the influence of N-fertilizer on the yield and yield components of eggplant (Solanum melongena L.) the experiment consisted of two varieties of eggplants green variety encoded as NC-2, the Off-white variety encoded as NC-1 and three urea fertilizer levels (0, 100, 200kgN/ha). Factorial combination of the treatments gave a total of six treatments which was laid in a Randomized Completed Block Design (RCBD) with four replications. Urea fertilizer was applied in 2-split doses first at 3weeks after planting and the second dose was applied at fruiting. Parameters measured include: plant height, number of leaves, stem girth, fruit diameter, number of nodes, number of branches, number of fruits per plant, number of flowers per plant, fruit weight. Fertilizer application significantly increased the yield of the two varieties. However, NC-2 (green variety) appears to respond more to higher N-application (up to 200kgN/ha) as compared to NC-1 (off- white variety). Also, fertilizer had significant effect on vegetative characters, yield and some yield components. The yield were found to be statistically at par. Key words: Eggplant, Number of branches, Number of fruits, Fruit diameter, Fruit yield, number of flowers, number of nodes, number of leaves, plant height. INTRODUCTION Background to the study Eggplant (Solanum melongena L.) is an economically important vegetable crop across many countries in Asia and Africa (Collonnier et al., 2003). In Nigeria, it has been reported that little attention is paid to traditional vegetables which have high nutritive value like eggplant (Okezie and Okoye, 2006). Eggplant is a long duration crop with high yield which removes large quantities of nutrients from the soil (Hedge, 1997). The crop is widely cultivated across most of the African continent and more intensively in west and east Africa. It’s consumed almost on a daily basis by urban families and also represents the main source of income for producing households in the forest zone of West Africa (Danquah-jones, 2000). Eggplant is a long duration crop with high yield which removes large quantities of nutrients from the soil (Hedge, 1997). The crop is widely cultivated across most of the African continent and more intensively in west and east Africa. It’s consumed almost on a daily basis by urban families and also represents the main source of income for producing households in the forest zone of West Africa (Danquah-jones, 2000). In West Africa, the eggfruits are eaten raw, cooked or fried with spices in stews, or dried and pound as condiments (AVRDC, 2008). Nitrogen and phosphorus are the usually most limiting nutrients elements in most soils in Africa and are often simultaneously deficient (Suge et al., 2011). Applied N is taken up by the crop in the field or immobilized in soil organic N pools, which is vulnerable to losses from volatilization, de-nitrification, and leaching (Cassman, 2002). Studies have shown that leaving the ground bare between fall and spring cropping periods increases the risk of nutrients leaching into ground water. Nitrate nitrogen is among the most significant nutrients lost through this process due to greater solubility (Li and Reddy 1997). Eggplant production in Nigeria is constrained by the low level of soil fertility, coupled with poor prevailing climatic conditions and this result in low yield of the plant. Constraints and the problem of soil nutrients of low to medium level of available nutrients have caused yield below potential levels