Electronic Theses and Dissertation

Penggunaan herbisida sintetis secara terus-menerus untuk mengendalikan gulma dapat menyebabkan resistensi gulma, pencemaran lingkungan serta dampak negatif terhadap kesehatan manusia. Oleh karena itu, diperlukan alternatif pengendalian yang lebih ramah lingkungan melalui pemanfaatan bioherbisida berbahan alelopati tanaman. Penelitian ini bertujuan untuk mengidentifikasi tanaman yang paling berpotensi dijadikan bioherbisida terhadap pertumbuhan gulma bayam duri. Keberhasilan ekstraksi dipengaruhi oleh kesesuaian polaritas pelarut dan senyawa yang diekstraksi. Etil asetat dipilih karena bersifat semipolar sehingga mampu mengekstraksi senyawa alelokimia polar dan nonpolar. Penelitian ini dilaksanakan di Laboratorium Ilmu Gulma Departemen Agroteknologi, Laboratorium Farmakologi Fakultas Kedokteran Hewan, Laboratorium Kimia Organik Departemen Kimia Fakultas Matematika dan Ilmu Pengetahuan Alam dan Rumah Kaca Fakultas Pertanian, Universitas Syiah Kuala, Banda Aceh yang berlangsung dari bulan Desember 2025 hingga Februari 2026 dengan menggunakan Rancangan Acak Lengkap non faktorial, 17 perlakuan dan 3 ulangan yaitu, 2, 4-D 0,686 kg ba ha-1 (kontrol positif), aquades (kontrol negatif), ekstrak etil asetat daun pinus, akasia, jati, ketapang dan jarak pagar masing-masing konsentrasi 20%, 30% dan 40%. Hasil penelitian menunjukkan bahwa aplikasi ekstrak etil asetat jati dan jarak pagar konsentrasi 20%, akasia, pinus dan ketapang konsentrasi 30% menyebabkan kematian gulma bayam duri pada 7 HSA, sedangkan ekstrak etil asetat ketapang konsentrasi 20% menunjukkan efektivitas penghambatan terendah hingga 28 HSA. Hasil uji fitokimia menunjukkan bahwa alkaloid, tanin dan fenolik dimiliki oleh seluruh tanaman yang diuji, steroid dimiliki oleh pinus, jati, ketapang dan jarak pagar, flavonoid dimiliki oleh pinus dan jati sementera saponin tidak dimiliki oleh semua tanaman yang diuji.

Kata kunci: Bioherbisida, Etil Asetat, Amaranthus spinosus L.

The continuous use of synthetic herbicides for weed control may lead to weed resistance, environmental pollution, and adverse effects on human health. Therefore, environmentally friendly alternative control methods are needed through the utilization of plant-based bioherbicides derived from allelopathic plants. This study aimed to identify plant species with the greatest potential as bioherbicides against the growth of spiny amaranth (Amaranthus spinosus L.). The effectiveness of extraction is influenced by the compatibility between the polarity of the solvent and the compounds being extracted. Ethyl acetate was selected as the extraction solvent because its semipolar nature enables the extraction of both polar and nonpolar allelochemicals. This research was conducted at the Weed Science Laboratory, Department of Agrotechnology; the Pharmacology Laboratory, Faculty of Veterinary Medicine; the Organic Chemistry Laboratory, Department of Chemistry, Faculty of Mathematics and Natural Sciences; and the Greenhouse of the Faculty of Agriculture, Syiah Kuala University, Banda Aceh, from December 2025 to February 2026. The experiment employed a non-factorial Completely Randomized Design consisting of 17 treatments and three replications, including 2,4-D at 0.686 kg b.a. ha⁻¹ (positive control), distilled water (negative control), and ethyl acetate extracts of pine, acacia, teak, tropical almond, and physic nut leaves at concentrations of 20%, 30%, and 40%. The results showed that ethyl acetate extracts of teak and physic nut at 20% concentration, as well as acacia, pine, and tropical almond at 30% concentration, caused the death of spiny amaranth at 7 days after application. In contrast, the 20% ethyl acetate extract of tropical almond exhibited the lowest inhibitory effect up to 28 days after application. Phytochemical analysis revealed that alkaloids, tannins, and phenolics were present in all tested plants; steroids were detected in pine, teak, tropical almond, and physic nut; flavonoids were found in pine and teak; whereas saponins were absent in all tested plants. Keywords: Bioherbicide, Ethyl Acetate, Amaranthus spinosus L.