Effects of Phosphorus and Organic fertilizers on the Yield and Proximate nutrient composition of lettuce (<i>Lectuca sativa</i>) in Southwestern nigeria

Abstract

A field experiment was conducted to evaluate the effect of different types of organic manure, phosphorus fertilizers and their combinations on the yield attributes and proximate nutrient composition of lettuce grown in Akure and Ikorodu, Southwestern Nigeria. The study involved three types of organic manure (poultry, pig and cattle manures) and two types of phosphorus fertilizer (Ogun Rock Phosphate (RP) and Single Super Phosphate (SSP)) and a control with no fertilizer application resulting in sixteen (16) treatment combinations. The experimental design was Randomized Complete Block Design (RCBD) with three replicates. Yield was determined by weighing the fresh harvested lettuce and dry weight at 50 days after transplanting (DAT) and lettuce harvested were subjected to proximate composition analysis. The result of the study showed that lettuce grown on soil amended with organic manure combined with SSP and RP at 8t/ha -1 and 4t/ha -1 respectively exhibited significant higher yield. It also influenced the proximate composition positively at harvest compared to control and sole organic manure application. The result obtained clearly indicated that organic manure combined with phosphorus fertilizers prove to be a sound soil fertility management strategy in the study area. This should be adopted by would-be farmer of lettuce, as combinations of organic manures increase solubility of phosphorus and improve lettuce proximate nutrient composition.