Pertumbuhan dan Serapan Hara Pada Tanaman Cabai (Capsicum annum L.) dengan Pemberian Berbagai Dosis Pupuk Anorganik (N, P, K) dan Biochar Kelapa Sawit di Tanah Ultisol

Abstract

This research aims to obtain the best combination of fertilizers using various types of oil palm biochar to increase the productivity of ultisol soil in chili plants. This research was carried out in the greenhouse and Research and Technology Laboratory, Faculty of Agriculture, University of North Sumatra. The reseacrh used a factorial randomized block consisting of two factors with three replications. The first factor is the NPK dose which consist of four treatment levels: without NPK (D0), 65% NPK dose (D1), 100% NPK dose (D2), and 130% NPK dose (D3). The second factor is palm oil biochar which consists of 4 types of treatment, namely: without biochar (B₀), oil palm empty bunch biochar (B₁), palm oil shell biochar (B₂), and palm oil stem biochar (B₃) with respective doses 150g/10 kg of ultisol soil each. The research results showed that giving a dose of 65% NPK fertilizer (1 g/polybag) was the best dose in increasing soil organic C-organics and P uptake of chili plants. Oil palm stem biochar is better than other biochar in increasing soil pH, soil organic C, plant height, number of plant branches, shoot dry weight, uptake of N, P and K of chili plants. The treatment interaction of giving a dose of 100% NPK fertilizer (1,6 g/polybag) with palm oil stem biochar gave significantly different effects in each treatments and it was able to improve soil chemical characteristics by improving soil pH, soil organic C, and was able to increase plant height, N, P, and K uptake of chili plants.