Uji Keefektifan Antijamur Ekstrak Air Rimpang Lengkuas (Alpinia galanga [L] Willd.) sebagai Perlakuan Pratanam untuk Mengendalikan Colletotrichum spp. pada Kedelai (Glycine max L.)

Abstract

ABSTRACTAntifungal Effect of Aqueous Extract of Galangal (Alpinia galanga [L] Willd.) Rhizomeas Seed Treatment to Control Colletotrichum spp. of Soybean (Glycine max L.)Colletotrichum is one of the most important seed-borne pathogens of soybean which is usuallycontrolled with synthetic fungicide seed treatment. However, it is believed that the use ofsynthetic fungicide can cause a variety of negative impacts to the environment and humanhealth. Galangal rhizome extract has been widely reported to have antifungal and antibacterialproperties. The aim of the study was to investigate the effectiveness of galangal rhizomeaqueous extract as antifungal for pre-planting seed treatment to control Colletotrichum spp. insoybean. Laboratory and glasshouse experiments were carried out at the Department of PlantPests and Diseases, Faculty of Agriculture, Universitas Padjadjaran. The method used was anexperimental method to test the effectiveness of galangal rhizome aqueous extract against theemergence and spore germination suppression of Colletotrichum spp., and to test the seedviability and plant growth of soybean. Galangal rhizome extract with concentrations of 10%,30%, 50%, 70%, 90% and 100% as well as a metalaxyl fungicide (0.5 g/l) were applied as aseed treatment. The results showed galangal rhizome aqueous extract at concentration of100% reduced the presence of Colletotrichum spp. in seeds up to 100% after the treatment andsuppressed the spore germination by 76.20% as well as increased the seed viability and thegrowth of soybean plants.Keywords: Alpinia galanga, aqueous extract, seed treatment, soybean, Colletotrichum spp.ABSTRAKUmumnya pengendalian penyakit tular benih pada kedelai dilakukan melalui perlakuan benihdengan menggunakan fungisida sintetik yang diakui dapat menimbulkan berbagai dampak negatifpada lingkungan maupun kesehatan manusia. Penggunaan ekstrak air rimpang lengkuas untukperlakuan benih dapat diterapkan sebagai alternatif pengendalian penyakit tular benih padakedelai. Lengkuas telah banyak dilaporkan memiliki sifat antijamur dan antibakteri. Penelitian inidilaksanakan dengan tujuan untuk mengetahui keefektifan ekstrak air rimpang lengkuas sebagaiantijamur untuk perlakuan benih dalam mengendalikan penyakit tular benih pada kedelai.Percobaan dilaksanakan di Laboraturium Fitopatologi dan rumah kaca Departemen Hama danPenyakit Tumbuhan, Fakultas Pertanian, Universitas Padjadjaran. Metode penelitian yangdigunakan adalah metode eksperimen dengan pengujian keefektifan air persaan rimpang lengkuasterhadap kemunculan, penekanan perkecambahan konidia, uji pertumbuhan benih, dan viabilitasbenih jamur Colletotrichum spp. pada kedelai. Ekstrak air rimpang lengkuas dengan konsentrasi10%; 30%; 50%; 70%; 90%; dan 100% serta fungsida berbahan aktif metalaksil (0,5 g/l)diaplikasikan sebagai perlakuan benih kedelai. Hasil percobaan menunjukkan ekstrak air rimpanglengkuas konsentrasi 100% dapat menekan sampai 100% kemunculan Colletotrichum spp. setelah perlakuan benih, menekan perkecambahan konidia sebesar 76,20% serta meningkatkanpertumbuhan dan viabilitas benih kedelai.Kata kunci: engkuas, ekstrak air, perlakuan benih, kedelai, Colletotrichum spp.