Abstract

The potential yield of sunflower can be attained by optimizing nitrogen application for specific soil types. Therefore, this study was conducted during autumn and spring seasons of 2019 in the greenhouse structure of North-West University, South Africa to evaluate the effect of N based fertilizer and soil type on the performance of sunflower. A pot experiment was laid out in 2 × 6 factorial design fitted in a complete randomised design with three replications. Two soil types were clay loam and sandy loam with six nitrogen fertilizer rates (0, 90, 120, 150, 180 and 200 kg/ha). Growth parameters viz., plant height, number of leaves per plant, leaf area, chlorophyll content and stem diameter were recorded. Soil type had significant effect (p≤0.05) on number of leaves per plant and leaf area. Sunflower planted on clay loam soil had significantly higher number of leaves of 11.86 and 15.61 per plant on 46 and 60 days after planting, respectively. Sunflower planted on clay loam soil also had significantly higher leaf area of 194.5 cm2 on 74 days after planting. Nitrogen fertilizer rate had significant effect (p≤0.05) on sunflower leaf area and chlorophyll content. Sunflower treated with 180 kg N/ha had significantly large leaf area of 221.4 cm2 and higher chlorophyll content index (CCI) of 18.73. The results of this study reveal that clay loam soil is more suitable for production of sunflower. Nitrogen fertilizer rate of 180 kg/ha can be considered optimum for higher growth and development of sunflower.