Analisis Pupuk Majemuk dengan Penambahan Variasi Asam Fulvat terhadap Pertumbuhan Tanaman Sawi Hijau ( Brassica juncea L. )

Abstract

This research was about the effect of adding variations of fulvic acid to compound fertilizer on the growth of mustard greens (Brassica juncea L.). The study was conducted with the aim of analyzing whether the N, P, and K nutrient contents in the compound fertilizer with the addition of various levels of fulvic acid met the standards according to the Indonesian National Standard (SNI) 2803-2024, which was established by the National Standardization Agency, and followed by the application of the compound fertilizer to the growth of mustard greens (Brassica juncea L.). The research was carried out using a Completely Randomized Design (CRD) non-factorial method with five levels of treatment: without fertilizer (P0), control fertilizer (P1), fertilizer with the addition of 1 g fulvic acid (P2), fertilizer with the addition of 2 g fulvic acid (P3), and fertilizer with the addition of 3 g fulvic acid (P4), with three replications. The observed parameters included plant height, number of leaves, and plant fresh weight as growth indicators, as well as the analysis of N, P, and K nutrient contents in the compound fertilizer using the Kjeldahl, UV-Vis Spectrophotometry, and Flame Photometry methods. The data obtained were analyzed using ANOVA and followed by Duncan’s Multiple Range Test (DMRT) at a 0,05% significance level. Based on the results of the research, the addition of fulvic acid, particularly at a dose of 3 g, had a significant effect on the growth of mustard greens and improved soil quality as the growing medium. This was indicated by increases in several soil parameters, including soil pH (from 5,46 to 6,95), available phosphorus (from 14,28 to 26,57), exchangeable potassium (from 0,27 to 0,62), organic carbon (from 1,05 to 4,18), cation exchange capacity (from 15,65 to 27,18), and total nitrogen (from 0,18 to 0,51). The NPK contents of the compound fertilizer were as follows: Nitrogen (P2) 10,8%; (P3) 11,6%; and (P4) 12,7%; Phosphate (P2) 6,05%; (P3) 6,17%; and (P4) 6,24%; Potassium (P2) 20,8%; (P3) 21,3%; and (P4) 21,5%. The plant growth parameters showed that plant height reached 30,33 cm, the number of leaves was 22,33 leaves, and the fresh weight per plant was 90,73 g. Based on the NPK analysis of the compound fertilizer with the addition of fulvic acid variations, it was shown that each fertilizer variation met the quality standards in accordance with SNI 2803-2024.