Investigating the Influence of Inorganic and Organic Fertilizers on the Growth and Yield of Three Varieties of Okra (<i>Abelmoschus esculentus</i>)

Fertilizers play an important role in enhancing crop yield, growth, and fertility of the soil. This research was conducted at the Faculty of Agriculture teaching and research farm, University of Port Harcourt, Nigeria to investigate the influence of inorganic fertilizer (urea) and organic manure (spent mushroom substrate and poultry manure) on the yield and growth parameters of three okra cultivars (Clemson Spineless, Perkin Long Pod and the Local Assertion). The urea was applied at the rate of 4g per 10kg of soil, while spent mushroom substrate and poultry manure were applied at the rates of 200g and 150g per 10kg of soil respectively at 4 weeks after planting. The treatments were laid in a completely randomized design (CRD) with 3 replications. The results revealed that the okra cultivars responded positively to both organic manures when compared with urea and the control group where no fertilizer was applied. Furthermore, varieties grown with poultry manure generally had the highest fresh fruit weight, plant height, fruit length, number of fruits, and fresh fruit yield. Spent mushroom substrate influenced the number of fruits and fruit yield while urea influenced the leaf area, number of leaves, and leaf area index. Poultry manure was recorded as the best organic manure for okra growth and yield and is recommended to be used to grow okra plants. Also, the Perkin Long Pod variety is recommended to be the best for cultivation.