Enhancing Growth, Yield, and Marketable Tuber Quality of Potato (Solanum tuberosum L. cv. BARI Alu-88) through Supplementary Vermicompost Application under Coastal Conditions of Bangladesh

Abstract

Potato (Solanum tuberosum L.) is an important food and cash crop in Bangladesh; however, production in coastal regions is constrained by poor soil fertility and salinity stress. Vermicompost has emerged as a sustainable soil amendment capable of improving soil health and crop productivity. Therefore, the present study was conducted to evaluate the effects of different rates of supplementary vermicompost under a recommended inorganic fertilizer regime on the growth and yield of the potato cultivar BARI Alu-88 under coastal conditions. The experiment was carried out during the 2021–2022 growing season at the field of Noakhali Science and Technology University using a randomized complete block design (RCBD) with four treatments: T₀ = control (recommended inorganic fertilizer only), T₁ = recommended inorganic fertilizer + vermicompost @ 3.5 t ha⁻¹, T₂ = recommended inorganic fertilizer + vermicompost @ 5.5 t ha⁻¹, and T₃ = recommended inorganic fertilizer + vermicompost @ 7.5 t ha⁻¹, with three replications each. Supplementary vermicompost application significantly (P ≤ .01) improved all growth and yield attributes compared with the recommended inorganic fertilizer alone. The highest vermicompost rate (T₃) produced the tallest plants (56.73 cm), the greatest numbers of leaves (495.03 hill⁻¹), stems (7.60 hill⁻¹), and tubers (21.55 plant⁻¹), and the highest gross tuber yield (40.44 t ha⁻¹) and marketable yield (36.79 t ha⁻¹). Moreover, T₃ reduced the proportion of small-sized tubers (19.32%) while increasing the proportion of large-sized tubers (50.05%). The findings indicate that supplementary vermicompost application under the recommended inorganic fertilizer regime markedly enhanced vegetative growth, tuber development, and yield performance of BARI Alu-88 under coastal conditions. Although vermicompost is recognized as an environmentally friendly soil amendment, its adoption in the coastal saline areas of Bangladesh remains limited. The findings of the present study indicate that applying vermicompost at 7.5 t ha⁻¹ significantly improves the growth and yield of BARI Alu-88 under saline conditions. Therefore, supplementing the recommended inorganic fertilizer with vermicompost at 7.5 t ha⁻¹ can be recommended as an environmentally sustainable nutrient-management strategy for improving potato productivity in the coastal regions of Bangladesh.