Eksplorasi dan Karakterisasi Bakteri Endofit Asal Tanaman Padi Sawah di Kabupaten Aceh Besar

Abstract

Abstrak. Komunitas bakteri endofit adalah komunitas mikroorganisme yang menguntungkan bagi tanaman inang yang hidup di dalam dan pada jaringan tanaman tanpa menimbulkan gejala pada tanaman inangnya dan bersifat simbiosis mutualisme dan berperan sebagai agen biokontrol. Kelimpahan bakteri pada tiap bagian tanaman berbeda karena dipengaruhi oleh faktor internal (faktor biotik) yang meliputi tanaman dan bakteri dan faktor eksternal (faktor abiotik) yang meliputi faktor lingkungan. Pada umumnya, bakteri endofit memiliki kisaran inang yang luas dan dapat berperan sebagai pengendalian hayati yaitu alternatif pengendalian yang lebih aman bagi lingkungan. Beberapa bakteri agens antagonis pada tanaman padi yang telah berhasil diisolasi antara lain Bacillus cereus, Pantoea ananatis, Methylobacterium sp., Paenibacillus amylolyticus, Stenotrophomonas maltophilia, dan Streptomyces sp. Penelitian ini bertujuan untuk mengeksplorasi dan mengkarakterisasi bakteri endofit yang berasosiasi dengan tanaman padi sawah. Penelitian ini adalah jenis penelitian eksploratif dengan peubah yang diamati meliputi seleksi bakteri endofit non patogen pada uji hipersensitivitas daun tanaman tembakau, karakterisasi bakteri endofit secara makroskopis dan mikroskopis. Hasil penelitian menunjukkan terdapat 92 isolat bakteri endofit yang berhasil diisolasi dari akar, batang, dan daun tanaman padi. Sebanyak 72 isolat bersifat potogen dan 20 isolat non patogen. Karakterisasi morfologi bakteri endofit terhadap 20 isolat bakteri non patogen menunjukkan 15 isolat bakteri bersifat Gram positif dan 5 lainnya bersifat Gram negatif. Sebanyak 19 isolat termasuk katalase positif dan 1 isolat katalase negatif. Isolat BST3(3) dan ASS2(4) diduga sebagai isolat bakteri dari genus Paenibacillus, isolat AST4(3), AST4(2), dan ASS3(3) diduga termasuk bakteri dari genus Bacillus, dan isolat BST2(2) diduga sebagai isolat bakteri dari genus Pseudomonas.

Exploration and Characterization of Endophytic Bacteria from Paddy Rice Plants in Aceh Besar District

Abstract. The endophytic bacterial community is a community of microorganisms that are beneficial to host plants that live in and on plant tissues without causing symptoms in the host plant and are symbiotic mutualism and acting as biocontrol agents. The abundance of bacteria in each part of the plant is different because it is influenced by internal factors (biotic factors) which include plants and bacteria and external factors (abiotic factors) which include environmental factors. In general, endophytic bacteria have a wide host range and can act as biological control, an alternative control that is safer for the environment. Some antagonistic bacteria on rice plants that have been successfully isolated include Bacillus cereus, Pantoea ananatis, Methylobacterium sp., Paenibacillus amylolyticus, Stenotrophomonas maltophilia, and Streptomyces sp. This study aims to explore and characterise endophytic bacteria associated with paddy rice plants. This research is an exploratory type of research with observed variables including the selection of non-pathogenic endophytic bacteria in the hypersensitivity test of tobacco plant leaves, characterisation of endophytic bacteria macroscopically and microscopically. The results showed that there were 92 isolates of endophytic bacteria that were successfully isolated from the roots, stems, and leaves of rice plants. A total of 72 isolates were potogenic and 20 isolates were non-pathogenic. Morphological characterisation of endophytic bacteria on 20 non-pathogenic bacterial isolates showed 15 bacterial isolates were Gram positive and 5 others were Gram negative. A total of 19 isolates were catalase positive and 1 isolate was catalase negative. Isolates BST3(3) and ASS2(4) were thought to be bacterial isolates of the genus Paenibacillus, isolates AST4(3), AST4(2), and ASS3(3) were thought to be bacteria of the genus Bacillus, and isolate BST2(2) was thought to be a bacterial isolate of the genus Pseudomonas.