Potensi Cendawan Endofit Asal Pohon Pingku (Dysoxylum parasiticum) Sebagai Agens Biokontrol Penyakit Busuk Buah Kakao (Phytophthora palmivora Butl.)

Abstract

Endophytic fungi (EF) colonize plant tissues without causing disease symptoms and can enhance host resistance by producing secondary metabolites. The pingku tree (Dysoxylum parasiticum), a member of Meliaceae family, is known for its antimicrobial compounds and serves as a potential source of beneficial endophytes. This study evaluated the antagonistic potential of EF isolated from D. parasiticum against Phytophthora palmivora, the pathogen responsible for cacao black pod disease. P. palmivora was isolated from surface-sterilized infected cacao pod tissues and cultured on ISP2 medium. Forty EF isolates were screened for antifungal activity using dual-culture (DC) and volatile organic compounds (VOCs) assays, alongside assessments for cellulose and glucan degradation abilities. Performance ranking was conducted using the Analytical Hierarchy Process (AHP). The four highest-ranked isolates underwent pathogenicity testing on rice seeds, with the two most promising then evaluated for in vivo efficacy on cacao pods. In DC assays, inhibition ranged from 54.01–92.42%, while VOCs-mediated inhibition ranged from 2.53–20.88%. Thirty-five isolates successfully degraded cellulose and/or glucan. In vivo evaluation identified isolate SKUPP as the most effective treatment, yielding a relative inhibition 51.71%.

Cendawan endofit (CE) merupakan cendawan yang hidup di dalam jaringan tanaman tanpa menyebabkan gejala penyakit pada inangnya. CE berasosiasi dengan inangnya untuk menghasilkan metabolit sekunder yang melindungi inangnya. Pohon pingku (Dysoxylum parasiticum) merupakan spesies dari famili Meliaceae yang dilaporkan banyak mengandung senyawa antimikrob. Penelitian ini bertujuan menguji CE asal pohon pingku dalam mengendalikan Phytophthora palmivora penyebab buah busuk kakao. Isolasi P. palmivora dilakukan dengan menanam jaringan sakit yang telah steril pada media ISP2. Sebanyak 40 isolat CE diuji potensi hambatan terhadap P. palmivora melalui uji dual-culture (DC) dan volatile organic compound (VOC) lalu diuji kemampuan mendegradasi senyawa selulosa dan glukan. Hasil uji diseleksi menggunakan analytical hierarchy process, 4 isolat terbaik diuji patogenisitas terhadap benih padi, 2 isolat terbaik diuji keefektifannya pada buah kakao (in vivo). Hasil penelitian menunjukkan presentase hambatan pada DC 54,01 – 92,42% dan pada VOC 2,53 - 20,88%, dan 35 isolat diketahui mampu mendegradasi selulosa dan/atau glukan. Uji in vivo menunjukkan isolat SKUPP sebagai isolat terbaik dengan hambatan relatif mencapai 51.71%.