Karakterisasi Fisiologis Rizobakteri Secara In Vitro Terhadap Penyakit Busuk Buah Kakao (Phytophthora palmivora L.)

Abstrak. Salah satu perkebunan di Indonesia menghasilkan kakao (Theobroma cacao L.), yang memberikan kontribusi signifikan terhadap perekonomian dan cadangan devisa Indonesia. Masih terdapat tantangan dalam pengembangan seluruh Indonesia, termasuk Provinsi Aceh, antara lain adanya penyakit hama berkontribusi rendahnya produktivitas kakao. Penelitian ini bertujuan adalah untuk mendapatkan isolat rizobakteri mampu berperan sebagai kandidat agen biokontrol menghambat pertumbuhan koloni patogen P. palmivora secara in vitro. Disamping itu penelitian mengetahui apakah jenis indigenous dapat pemacu tanaman dengan palmivora. dilaksanakan Laboratorium Ilmu Teknologi Benih Fakultas Pertanian, Universitas Syiah Kuala, Darussalam Banda Aceh. Pelaksanaan dimulai pada bulan Oktober 2020 sampai Mei 2021. Rancangan Acak Lengkap (RAL) non-faktorial digunakan ini. Faktor diteliti yaitu sebanyak 8 isolat. Pengamatan dilakukan mencakup daya hambat patogen, laju penghambatan, aktivitas enzim protease, kemampuan melarut fosfat, produksi IAA, HCN, senyawa siderofor. Hasil menunjukkan bahwa GM 8/1 7/10 merupakan dua memiliki sangat tinggi. Sedangkan penghambatan relatif lebih tinggi diperoleh dari 8/3. Sementara protease tertinggi 5/6 7/10. Kemampuan fosfat Isolat IAA 8/1, 8/3 8/11. Produksi HCN 3 5/6, 8/8. Semua memproduksi siderofor.Kata kunci : Kakao, Fisiologis Rizobakteri, In VitroPhysiological Characterization of Rhizobacteria Vitro Against Cocoa Fruit Rot Disease (Phytophthora Palmivora L.)Abstract. L.) is one the plantation commodities which has an important role for national economy to increase country’s foreign exchange. development broadly, including Aceh Province, still faces obstacles, namely presence pests and diseases that cause low cocoa productivity The aim this study was obtain rhizobacteria isolates capable acting as candidates biocontrol agents inhibiting growth pathogenic colonies addition, aims determine whether can act plant promoting with This research conducted at Laboratory Seed Science Technology, Faculty Agriculture, Kuala University, Darussalam, implementation began October until May used a non-factorial completely randomized design (CRD) method. factors studied were types isolates. observations made included inhibition colonies, rate inhibition, activity enzyme, ability dissolve phosphate, production siderophores. results showed two had very high inhibitory power. While relatively higher obtained from Meanwhile highest enzyme found isolate isolate. phosphate solubilizing Isolated produced compounds 8/11 rhizobacteria, 5/6. 8/8.Keywords: Cacao, Physiological Rhizobacteria,