Integrated application of wood ash and inorganic fertilizer sources on vegetative growth, fruit yield, and nutrient quality of Solanum aethiopicum L.

Abstract

Purpose: Wood ash is an important alternative source of inorganic potassium especially for farmers in areas with acidic soils. Method: The experiment was carried out in two phases. In the first phase, treatments consisted of the application of inorganic fertilizer sources (0 kgha-1, 130.44 kgha-1 of urea, and 300 kgha-1 of NPK of 20:10:10) and wood ash (0 tha-1, 5 tha-1 , and 10 tha-1) to garden egg seedlings. In the second phase of the experiment, garden eggfruits were analyzed for nutrient contents. Results: Significant (p≤0.05) fruit yield followed this order: 10 tha-1 of wood ash > control > 5 tha-1 of wood ash. Inorganic fertilizer sources effect on fruit yield followed this sequence: 300 kgha-1 of NPK 20:10:10 > 130.44 kgha-1 of urea > control. The interaction of 10 tha-1 of wood ash and 300 kgha-1 of NPK 20:10:10 produced the highest fruit yield (57 ± 0.50 tha-1). A combined application of 300 kgha-1 of NPK and 5 tha-1 of wood ash showed a greater improvement in vitamin C while an integrated application of 130.44 kgha-1 of urea and 10 tha-1 of wood ash increased vitamin A contents of garden egg. Conclusion: Integration of 10 tha-1 of wood ash and 300 kgha-1 of NPK 20:10:10 positively improved the growth and yield of the garden egg. The addition of a lower rate of wood ash to NPK fertilizer and a higher rate of wood ash to urea significantly improved the nutrient contents of garden eggs. Highlights ● Wood ash is an effective organic lime used in soil amendment of acidic soils. ● Fruit yield in garden eggs showed a linear increase with increasing rates of wood ash. ● Application of NPK fertilizer had superior fruit yield and quality to urea fertilizer. ● Potassium in wood ash and NPK fertilizer accounts for high fruit yield in garden egg. ●Integration of wood ash and inorganic fertilizers produced higher nutrient contents.

Keywords

• acidic soil
• fruit vegetable
• organic lime
• potassium
• soil amendment