Response of Okra Varieties to Different Fertilizer Level of Humic Acid

Abstract

Background and Objective: Poor soil fertility is a great limitation to crop production. The adverse effects of chemical fertilizer and the unavailability of organic fertilizer in large quantities are another challenge. The research was conducted at the Research Farm of Ekiti State University, Ado-Ekiti, Nigeria to examine the effects of appropriate doses of humic acid (HA) fertilizers for maximum performance of okra.
 Materials and Methods: The experiment was laid out in Randomized Complete Block Design (RCBD) with three replicates. The two factorial experiments comprise four levels of humic acid fertilizer (0, 5.0, 10.0, and 15.0 g HA plant-1) and NPK 15-15-15 (150 kg hac-1), and two okra varieties. The two okra varieties were allocated to main plots while the fertilizer levels were allocated to sub-plots. The collected data on final plant height (cm), the number of leaves per plant, the number of fruits per plant, the weight of fresh fruit per plant (g), the fruit length (cm), the leaf area (cm3), the fruit diameter (cm), and the stem diameter (cm) and analyzed with the IRRI STAR Software.
 Results: The result showed that the traits measured were significantly different for (HA) levels and NPK fertilizers. The varieties were significantly different for the measured traits except for leaf area, fruit diameter, and fruit length while the varieties x amendment levels were significant for plant height, leaf area, fruit diameter, and stem diameter while others are not significant. The measured traits increases as the humic acid levels increase. It was observed that the plants that received 15.0 g HA plant-1 performed better, followed by 10.0g HA plant-1 and NPK 15-15-15 respectively. However, the differences in the plants that received 5.0g HA plant-1 and 7.5g HA plant-1 were minute.
 Conclusion: It is therefore concluded that 5.0g HA plant-1 should be applied for optimal okra yield.