Pengaruh Jenis Ekstrak Dan Beberapa Variasi Konsentrasi Zat Alelopati Alami Dalam Menghambat Perkecambahan Benih Dan Pertumbuhan Bibit Kakao (Theobroma cacao L.)

Abstract

Kakao merupakan komoditi perkebunan strategis yang berkontribusi signifikan pada kegiatan ekspor-impor, meningkatkan devisa negara. Namun, pendistribusian benih kakao dihadapkan pada permasalahan rekalsitran, yang dapat diatasi dengan penggunaan alelopati alami. Alelopati alami mengandung senyawa toksis seperti alkaloid, fenolik dan terpenoid yang efektif menghambat perkecambahan. Tujuan dilakukan penelitian ini adalah untuk mengetahui pengaruh jenis ekstrak dan konsentrasi zat alelopati alami dalam menghambat proses perkecambahan benih dan pertumbuhan bibit kakao. Penelitian ini menggunakan Rancangan Acak Lengkap (RAL) Faktorial. Faktor pertama adalah jenis ekstrak yaitu akar alang-alang dan daun tomat. Faktor kedua adalah konsentrasi alelopati alami yaitu kontrol, 4%, 6%, dan 8%. Data di analisis apabila terdapat perbedaan yang nyata diantara perlakuan, maka dilakukan uji lanjut menggunakan uji jarak berganda Duncan pada taraf 5%. Hasil penelitian menunjukkan (1) interaksi antara jenis ekstrak dan konsentrasi zat alelopati alami berpengaruh nyata pada variabel pengamatan daya berkecambah, indeks vigor, lethal concentration (LC50), laju pertumbuhan tanaman, dan jumlah daun dengan hasil terbaik yaitu ekstrak akar alang-alang dan konsentrasi 4% alelopati alami. (2) Pengaruh jenis ekstrak alelopati alami berpengaruh nyata terhadap parameter indeks vigor, laju pertumbuhan tanaman, jumlah helai daun, dan diameter batang. (3) Pengaruh konsentrasi alelopati alami perlakuan berpengaruh tidak nyata pada semua variabel pengamatan.Cocoa is a strategic plantation commodity that contributes significantly to export-importactivities, increasing the country's foreign exchange. However, the distribution of cocoa seeds is faced with the problem of recalcitrant seeds, which can be overcome by using natural allelopathic substances. Natural allelopathic plant extracts contain toxic compounds such as alkaloids, phenolics, and terpenoids which are effective in inhibiting germination. The purpose of this study was to determine the effect of the type of extract and the concentration of natural allelopathic substances in inhibiting the process of seed germination and growth of cocoa seedlings. This study used a factorial Completely Randomized Design (CRD). The first factor was the type of extract, namely cogongrass roots and tomato leaves. The second factor was the concentration of natural allelopathic substances, namely control, 4%, 6%, and 8%. Data were analyzed using the ANOVA (Analysis of Variance) test. If there was a significant difference between treatments, further testing was carried out using Duncan's multiple range test at the 5% level. The results of the study showed (1) the interaction between the type of extract and the concentration of natural allelopathic substances had a significant effect on the observed variables of germination power, vigor index, lethal concentration (LC50), plant growth rate, and number of leaves, with the best treatment being the cogongrass root extract at a concentration of 4%. (2) The effect of the type of natural allelopathic extract had a significant effect on the parameters of vigor index, plant growth rate, number of leaves, and stem diameter. (3) The effect of the concentration of natural allelopathic substances had no significant effect on any of the observed variables.