Effects of micronutrients and their application efficiency on Capsicum production

A field experiment was conducted over two consecutive Rabi seasons (2023–2025) in Daharnangi, Rajshahi (AEZ-11), Bangladesh, to investigate the interactive effects of micronutrients (boron and zinc), application efficiency, and varietal response on the growth, yield, and nutritional quality of chili (Capsicum annuum L.). The study followed a split-split plot design with three replications and tested three chili varieties—Sikarpuri (V1), Sakata-653 (V2), and Picnic (V3)—under three fertilizer application methods: broadcast (E1), foliar spray (E2), and combined method (E3: 50% broadcast + 50% spray), and four micronutrient treatments: control (M0), boron (2 kg/ha, M1), zinc (4 kg/ha, M2), and combined boron + zinc (M3). The soil was silty clay loam with high pH and low micronutrient availability. The results revealed that the combined application of boron and zinc (M3) using the E3 method significantly improved plant height, fruit set, total yield, and biochemical parameters such as protein, carbohydrate, chlorophyll, calcium, and vitamin C content. The Picnic variety (V3) showed the highest performance in both years, with the maximum fresh fruit yields of 10.614 t/ha and 10.663 t/ha, along with superior values in fruit weight, seed weight, and nutritional quality. Sikarpuri performed better in terms of flavor and beta-carotene content, while Sakata showed lower overall performance. The findings demonstrate that the integrated application of boron and zinc through combined methods is effective in enhancing chili productivity and quality, especially in calcareous soils. The combined treatment of V3E3M3 (Picnic + 50% broadcast + 50% foliar + B+Zn) is recommended for commercial chili production in similar agro-ecological zones.