ANALISIS PATOGENISITAS DAN KARAKTERISASI KERAGAMAN GENETIK BANANA BLOOD DISEASE BACTERIUM (BDB)

INTAN BERLIAN, Prof. Dr. Ir. Siti Subandiyah, M. Agr. Sc.

2012 | Tesis | S2 Fitopatologi

Blood Disease Bacterium (BDB) merupakan patogen penyebab penyakit darah pada pisang yang menjadi salah satu penyakit penting karena menurunkan produksi pisang di Indonesia. Penelitian ini bertujuan untuk mengetahui patogenisitas BDB terhadap beberapa jenis tanaman selain tanaman pisang dan Heliconia sp. Mengetahui filogenetik BDB berdasarkan analisis repetitive-PCR (rep-PCR) yaitu BOX-PCR, ERIC-PCR dan REP-PCR dan dari sekuensing gen endoglukanase (egl). Mengetahui kemampuan BDB dalam menghasilkan bakteriosin secara in vitro. Penelitian dilaksanakan di Laboratorium Penyakit Tumbuhan, Fakultas Pertanian, Universitas Shizuoka, Jepang. Hasil penelitian menunjukkan bahwa BDB tidak mempunyai patogenisitas terhadap kecambah cabai, tomat, paprika, barli, padi, kacang hijau; bibit bawang merah; buah tomat, paprika; dan tangkai buah pisang. Filogenetik berdasarkan rep-PCR (BOX-PCR, ERIC-PCR dan REP-PCR) masing-masing mengelompokkan isolat BDB menjadi 3 grup, 2 grup dan kelompok yang sama dan dari filogenetik rep-PCR gabungan ketiganya mengelompokkan isolat BDB menjadi 6 grup. Analisis filogenetik hasil sekuensing melalui tahap kloning dari perwakilan rep-PCR BDB grup I dan II mengelompokkan keduanya ke dalam grup yang sama dengan tingkat kesamaan 100%. BDB dapat menghasilkan bakteriosin secara in vitro melalui uji zona hambat.

Banana blood disease caused by blood disease bacterium (BDB) is the most important disease because it reduces the production of banana in Indonesia significantly. The aims of this research are to determine pathogenicity of BDB on the plants other than bananas and Heliconia spp. Phylogenetic BDB was analyzed based on repetitive-PCR (rep-PCR) consisting of BOX-PCR, ERIC-PCR and REP-PCR and endoglucanase (egl) gene (s) sequence analysis. To determine the ability of BDB producing bacteriocin in vitro inhibition zone assay was used. The research was conducted in Laboratory of Plant Pathology, Faculty of Agriculture, Shizuoka University, Japan. The results showed that BDB was not pathogenic on sprouts of chili, tomato, bell pepper, barley, rice, mung bean; seedling of shallot; fruits of tomato, bell pepper and banana stalk. Phylogenetic BDB based on rep-PCR (BOX-PCR, ERIC-PCR and REP-PCR) separated the isolates into 3 groups, 2 groups, and a single group, respectively, and 6 groups from mix of all three rep-PCR. Phylogenetic based on the sequence of egl gene (s) analysis show that the representative rep-PCR of BDB group I and II was fall into one single group with the similarity level of 100%. BDB was produced bacteriocin based on inhibition zone assay against R. solanacearum #100EPPS1F and #2164.

Kata Kunci : Blood Disease Bacterium, patogenisitas, repetitive-PCR, kloning, sekuensing dan bakteriosin