Pengaruh Konsentrasi Ekstrak Metanol Babadotan (Ageratum conyzoides L.) terhadap Pertumbuhan Beberapa Jenis Gulma

Abstrak. Gulma merupakan tumbuhan yang tidak dikehendaki keberadaannya atau tumbuhan yang tumbuh liar pada lahan budidaya yang dapat menimbulkan kerugian sehingga perlu dikendalikan. Penelitian ini bertujuan Untuk mengetahui konsentrasi yang efektif dari ekstrak methanol babadotan dalam menghambat pertumbuhan gulma bayam duri, teki dan rumput kembang goyang. Penelitian dilaksanakan di Laboratorium Ilmu Gulma Jurusan Agroteknologi, Laboratorium Analisis Pangan Jurusan Teknologi Hasil Pertanian Fakultas Pertanian, Laboratorium Kimia Organik Fakultas Keguruan Ilmu Pendidikan, Laboratorium Analisis Kimia Fakultas Matematikan dan Ilmu Pengetahuan Alam serta Kebun Percobaan Fakultas Pertanian Universitas Syiah Kuala, Darussalam Banda Aceh sejak Juli - November 2017. Rancangan yang digunakan dalam penelitian ini adalah Rancangan Acak Lengkap (RAL) pola Non Faktorial, yaitu dengan menggunakan 3 jenis gulma A : bayam duri , B : teki, C : rumput kembang goyang dan ekstrak daun babadotan pada masing-masing gulma yaitu 0%, 10%, 20%, 30%, 40%, serta terdapat kontrol (herbisida 2,4D). Setiap perlakuan diulang sebanyak 3 kali dengan 3 tanaman indikator sehingga terdapat 54 satuan percobaan dan setiap satuan percobaan terdiri dari 4 unit gulma, sehingga terdapat 216 unit percobaan. Hasil Penelitian menunjukkan ekstrak metanol babadotan dengan konsentrasi 10 dan 20% mampu mengendalikan gulma bayam duri pada 7 HSA sebesar 93,75% dan pada 14 HSA sebesar 100%. Sedangkan pada rumput kembang goyang konsentrasi 20% pada 7 HSA mampu mengendalikan gulma sebesar 82,50% dan pada 14 HSA sebesar 93,33%. Ekstrak metanol babadotan berdasarkan uji fitokimia ditemukan senyawa steroid dan saponin, sedangkan hasil analisis Kromatografi Gas dan Spektometri Massa ditemukan 6 senyawa mayor terdiri dari senyawa 2H-1-Benzopyran, 7-(1,1-dimethylethyl)-2,3-dihydro-3,3-dimethyl, 3,7,11,15-Tetramethyl-2-hexadecen-1-ol, 9-Eicosyne, 9-Eicosyne dan Methyl Ester. The Effect of Whiteweed Methanol Extract ( Ageratum conyzoides L.) to Growth of some WeedsAbstract. Weeds are plants that are not desired for their existence or plants that grow wild on cultivated land that can cause harm so that need to be controlled. This study aims to determine the effective concentration of whiteweed methanol extract in inhibiting the growth of spiny amaranth, nutgrass and rocking grass. This research was conducted in Weed Science Laboratory and Experimental Garden Department of Agrotechnology, Food Analysis Laboratory Department of Food technology Faculty of Agriculture, Chemical Organic Department of Education Faculty, Chemical Analysis Mathematics and Natural Science faculty, University of Syiah Kuala, Darussalam Banda Aceh, from July to November 2017. This research using Randomized Completely Design with Non Factorial pattern, using 3 types of weeds, A : whiteweed, B : nutgrass, C : rocking grass and whiteweed leaves solvent for each weeds is 0%, 10%, 20%, and 40%,and has control (herbicide 2,4D). Each tretment has 3 replication with 3 indicator plants so that has 54 experimental units., each experimental unit consists of 4 weed units, so there are 216 experimental units.The results showed that whiteweed methanol extract with a concentration of 10 and 20% was able to control spinach weed in 7 HSA at 93.75% and at 14 HSA at 100%. Whereas on the rocking grass, the concentration of 20% in 7 HSA was able to control weeds by 82.50% and at 14 HSA by 93.33%. Whiteweed methanol extract based on phytochemical test found steroid and saponin compounds, while the results of Gas Chromatography and Mass Spectrometry analysis found 6 major compounds consisting of compounds: 2H-1-Benzopyran, 7-(1,1-dimethylethyl)-2,3-dihydro-3,3-dimethyl, 3,7,11,15-Tetramethyl-2-hexadecen-1-ol, 9-Eicosyne, 9-Eicosyne and Methyl Ester.