Evaluation of Post-Manure Application Planting Time and Poultry Manure Rate on Growth, Seed Yield and Yield Components of Egusi Melon

Abstract

Egusi melon (Citrullus colocynthis L) is a vegetable crop commonly cultivated for the seeds that majorly supply oil in human diet. Animal manure is used to amend and reclaim infertile soils. The rate and timing of manure application are determinants of its nutrient supply efficiency. Two field trials were conducted from September to December in 2017 and repeated from June to October in 2018 at the Federal University of Agriculture Abeokuta to determine effects of time and quantity of poultry manure application on growth and seed yield of Egusi melon. The factors were poultry manure rate of 0, 5, 10 or 15 t∙ha^-1 and post-manure application planting time at 2 or 4 weeks after manure application (WAMA). Treatments were arranged in a 2 × 3 factorial fitted into a randomized complete block design, replicated 4 times. In 2017, average number of leaves/plant was generally lower with Egusi melon planted at 2 weeks after manure application (WAMA), relative to 4 WAMA when the highest number of leaves was from 5 t∙ha^-1. Average leaf area and vine length were higher with planting at 4 WAMA. In 2018, number of leaves/plant and leaf area were similar with planting time and manure rate. First flowering in 2017 was attained in about 32 days with planting at 2 WAMA but in about 38 days with planting at 4 WAMA. In 2018, flowering was attained in 34 days with planting at 2 WAMA and in 32 days with planting at 4 WAMA. Seed yield at 2 WAMA in 2017 was highest (162 kg∙ha^-1) from 5 t∙ha^-1 and 237 kg∙ha^-1 at 4 WAMA. In 2018, highest seed yields were 1262 kg∙ha^-1 from 10 t∙ha^-1 at 2 WAMA, and 702 kg∙ha^-1 at 4 WAMA from 15 t∙ha^-1. Average fruit weight was higher in 2018. Number of seeds per fruit was highest in 2017 with planting at 4 WAMA. Application of 10 t∙ha^-1 poultry manure with Egusi melon planted at 2 WAMA is optimum for seed yield.