Determination of fertilizer rate recommendations for chili (Capsicum annuum L.) fertigation through drip irrigation using ferads (decision support system) in precision agriculture

Abstract

Location-specific fertilization rate recommendations are important for precision agriculture. This study aims to validate chili pepper fertilization recommendations in the field based on Ferads, a computer application program that is used to determine fertilizer recommendations for vegetable crops based on soil analysis. Two chili pepper varieties (Imola and Ori) were grown in Inceptisol soil with available content of 4.8 ppm P (very low), 44.2 ppm K (moderate), 1.53% organic C, and pH 6.46. Experiments were conducted at Cikarawang Field Station, IPB (250 m asl), from July to December 2021, set up in RCBD with four replicates and five fertilization rates. Nutrigads automatic fertigation machine was used for delivering fertilization treatment. The Imola variety obtained a quadratic response on marketable and total fruit weight per ha, with the line of equation Y = -1460.1x2 +2316.3x+5951.3, R²=0.3168, and Y=-3025.6x2 + 4272.2x + 12032; R² = 0.4237, with the optimum rate of x = 0.7931, and x= 0.7060, respectively. The prediction for the Imola variety was higher than the on field conditions, hence the Ferads fertilization recommendations are to be multiplied by 70%-79% for optimal implementation on farmers’ land. The Ferads rate had no effect on Ori variety, therefore, recommended rate is 100%.