Influence of organic and inorganic fertilizers on the morphological growth and yield of broccoli in coastal regions of Bangladesh

A field study was conducted to assess the combined effects of organic and inorganic fertilizers on the growth and yield of broccoli (Brassica oleracea var. italica) under coastal conditions in Bangladesh, characterized by slightly saline soil (EC 1.67 mS cm⁻¹). Six treatment combinations were tested: T₀ – Control (no fertilizer application); T₁ – 100% recommended dose of inorganic fertilizers (Urea, TSP, MoP); T₂ – 100% recommended dose of inorganic fertilizers + 2.5 t ha⁻¹ vermicompost; T₃ – 100% recommended dose of inorganic fertilizers + 5 t ha⁻¹ vermicompost; T₄ – 2.5 t ha⁻¹ vermicompost; and T₅ – 5 t ha⁻¹ vermicompost. Results showed that the combined application of 100% RDF with 5 t ha⁻¹ vermicompost (T₃) significantly improved all vegetative growth parameters, such as plant height, leaf number, leaf length, and leaf diameter, which subsequently enhanced curd diameter, net curd weight, and marketable curd weight, leading to the highest yield per plot. The strongest correlations (r = 0.946) were observed between yield and both net and marketable curd weight, indicating that curd biomass is the most direct determinant of yield. The study concludes that the integration of 100% RDF with 5 t ha⁻¹ vermicompost (T₃) is the most effective and sustainable nutrient management practice for maximizing broccoli growth and yield under coastal agro-ecological conditions of Bangladesh.