EFFECTS OF INORGANIC FERTILIZER (NPK) AND JATROPHA HUSK (JH) ON SELECTED SOIL CHEMICAL PROPERTIES AND GROWTH OF EGGPLANT (Solanum melongena)
Keywords:
Inorganic Fertilizer, Jatropha Husk, Soil Chemical Properties, Growth, Eggplant (Solanum melongena)Abstract
Cultivation of Solanum melongena (Eggplant) in the tropics is often confronted with low soil fertility, which indicates the need for sustainable approaches towards soil nutrient availability and management. Hence, this research focuses on the effects of inorganic fertilizer (NPK 15-15-15), Jatropha Husk (JH), and their combinations on the growth of Solanum melongena and selected properties of the soil, carried out at the Federal University of Technology, Akure. Randomized Complete Block Design was used with six treatments: control (no amendments), 100% JH, 100% NPK, 25% JH + 75% NPK, 50% JH + 50% NPK, and 75% JH + 25% NPK, replicated 3-times. Growth parameters measured were plant height, number of leaves, and stem diameter recorded bi-weekly, while pre-planting and post-planting soil analysis were analyzed. It was discovered that soil amendment significantly improved both plant leaf and height from four weeks post-planting. The highest measurements for leaf count (19.6) and plant height (44.40 cm) were observed with the treatment of 75% JH+ 25% NPK. Soil chemical characteristics were enhanced with 100% JH achieving the highest pH level (8.76), along with elevated concentrations of phosphorus, sodium, calcium, and potassium. Treatments with the largest amount of NPK resulted in slight soil acidification (pH 6.3). These findings suggest that using Jatropha husk, either singly or in combination with lower amounts of NPK fertilizer, can aid soil fertility and sustainable eggplant production. This study has revealed that a combination of JH and NPK has the potential to offer better growth output and improved soil quality.
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