<![CDATA[ABSTRACT Sengon wood (A. chinensis) is a type of wood that has great potential as a source of industrial raw materials and holds significant economic value. However, sengon wood has low natural durability, classified as durability class IV–V, making it highly susceptible to attack by wood-destroying organisms such as termites. Therefore, wood preservation treatment is necessary to extend its service life. This study aims to analyze the interaction effect between the concentration of gadung tuber (D. hispida) extract with ethanol solvent and the soaking duration on the durability of sengon wood using the cold soaking method. The extract concentrations used were 1%, 3%, and 5%, and the soaking durations were 1 day, 2 days, and 3 days. The preserved samples were subjected to forced feeding tests using 50 healthy and active drywood termites (C. cynocephalus Light) on test specimens measuring 2.5 cm × 2.5 cm × 2 cm. The preservative performance parameters included absorption and retention, while the wood durability parameters included weight loss and termite mortality rate. The interaction between gadung tuber extract concentration and soaking duration significantly affected the retention and absorption values, while weight loss and termite mortality showed no significant effect. The highest retention and absorption values were obtained at a soaking duration of 3 days and a concentration of 5%, with average retention and absorption values of 0.028 g/cm³ and 0.438 g/cm³, respectively Keywords: drywood termites, gadung tuber extract, sengon wood, wood preservation ABSTRAK Kayu sengon (A.chinensis) merupakan kayu yang memiliki potensi sebagai penyedia bahan baku industri dan memiliki nilai ekonomi yang cukup besar. Kayu sengon memiliki tingkat keawetan yang rendah, yaitu kelas awet IV-V sehingga sangat mudah diserang oleh organisme perusak kayu seperti rayap. Perlu dilakukan proses pengawetan kayu untuk meningkatkan umur pakai kayu. Penelitian ini bertujuan untuk menganalisis pengaruh interaksi antara konsentrasi ekstrak umbi gadung (D. hipsida) dengan pelarut etanol dan lama perendaman terhadap keawetan kayu sengon dengan metode perendaman dingin. Konsentrasi ekstrak yang digunakan 1%, 3% dan 5% dan lama perendaman yang dilakukan 1 hari, 2 hari dan 3 hari. Pengawetan diumpan paksa dengan rayap kayu kering (C. cynocephalus Light) yang sehat dan aktif sebanyak 50 ekor pada contoh uji yang berukuran (2,5 cm x 2,5 cm x 2 cm). Parameter pengujian bahan pengawet terdiri dari absorbsi dan retensi, sedangkan parameter pengujian keawetan kayu terdiri dari penurunan bobot dan nilai mortalitas rayap kayu kering. Interaksi antara konsentrasi ekstrak umbi gadung dan lama perendaman terhadap keawetan kayu sengon memberikan pengaruh nyata terhadap nilai retensi dan absorbsi, sedangkan penurunan bobot dan mortalitas tidak memberikan pengaruh nyata. Interaksi retensi dan absorbsi nilai tertinggi diperoleh pada lama perendaman 3 hari dan konsentrasi 5%, dengan nilai rata-rata retensi 0,028 g/cm3 dan absorbsi 0,438 g/cm³. Katakunci: ekstrak umbi gadung, kayu sengon, pengawetan kayu, rayap kayu kering]]>
