EFFICACY OF AMMONIUM GLUFOSINATE HERBICIDE ON WEEDS IN IMMATURE OIL PALM (Elaeis guineensis Jacq.) PLANTATIONS

Abstract

Oil palm is an important crop because it produces vegetable oil required by the industrial sector. Oil palm productivity can decline due to the presence of weeds, which can be controlled using herbicides containing the active ingredient ammonium glufosinate. Ammonium glufosinate can be used because its mode of action inhibits the enzyme responsible for producing the amino acid glutamine for detoxification, thus halting the photosynthesis process. This study aimed to determine the effective dose of 150 g/L ammonium glufosinate herbicide, to identify differences in weed composition, and to assess phytotoxicity in oil palm plants following herbicide application. The research was conducted from July to September 2024 in Muara Putih Village, Natar, South Lampung, and at the Weed Science Laboratory, Faculty of Agriculture, University of Lampung. The study used a Randomized Block Design (RBD) with six treatments: ammonium glufosinate 225 g/ha, ammonium glufosinate 300 g/ha, ammonium glufosinate 375 g/ha, ammonium glufosinate 450 g/ha, mechanical weeding, and a control (no treatment). Data homogeneity was tested using Bartlett’s test, additivity using Tukey’s test, and if assumptions were met, the data were analyzed using ANOVA followed by the Least Significant Difference (LSD) test at a 5% significance level. The results showed that herbicide doses of 300–450 g/ha were effective in controlling total weeds, grass weeds, broadleaf weeds, sedges, dominant broadleaf weed species, and the weed Digitaria ciliaris up to 8 weeks after application (WAA). Application of ammonium glufosinate herbicide caused differences in weed composition at 4 and 8 WAA, and all herbicide doses caused no phytotoxicity to oil palm plants.