Pengujian Bakteri Endofit Asal Cabai dalam Menekan Pertumbuhan Fusarium oxysporum f.sp. capsici Penyebab Penyakit Layu fusarium pada Cabai

Study of Endophytic Bacteria from Chili Peppers in Suppressing Growth of Fusarium. oxysporum f.sp. capsici the Causal Pathogen of fusarium Wilt Disease on Chili Peppers

Abstract

Endophytic bacteria are bacteria in plant tissues that do not cause disturbance in plants and can increase plant resistance to pests and pathogens as well increase plant growth. This study was aimed to determine the ability of endophytic bacteria isolated from chili plants in suppressing the development of fusarium wilt disease caused by Fusarium oxysporum f.sp. capsici and utilize the capability of several carriers as a medium for growing endophytic bacteria to be stored, transported and applied. Endophytic bacteria are bacteria in plant tissues that do not cause disturbance in plants and can increase plant resistance to pests and pathogens and increase plant growth. This study was aimed to determine the ability of endophytic bacteria isolated from chili plants in suppressing the development of fusarium wilt disease caused by fungus F. oxysporum f.sp. capsici. The in vitro antagonistic test results showed that the most effective endophytic bacteria againts isolate of F. oxysporum f.sp. capsici was BE 12 isolate (20.41%). Isolate BE 12 which reacts positively to the fluorescence test has an effect in inhibiting the growth of mycelium from fungus F. oxysporum f.sp. capsici because the endophytic bacteria belong to Pseudomonas fluorescens produces pyoluteorin and pyrrolnitrin compounds that are toxic to pathogen. The characteristic of morphology of all endophytic bacterial isolate a were circular colony with white colour,and flat elevation and undulate margin. Isolates of BE 2, BE 4 and BE 12 were Gram negative, while the other were Gram positive.

Bakteri endofit merupakan bakteri yang berada di dalam jaringan tanaman yang tidak menimbulkan gangguan pada tanaman dan dapat meningkatkan ketahanan tanaman terhadap serangan hama dan patogen serta meningkatkan pertumbuhan tanaman. Penelitian ini bertujuan untuk mengetahui kemampuan bakteri endofit yang diisolasi dari tanaman cabai dalam menekan perkembangan penyakit layu fusarium yang disebabkan oleh jamur Fusarium oxysporum f.sp. capsici. Hasil uji antagonis diperoleh bakteri endofit dengan isolat BE 12 yang paling efektif sebesar (20,41%) dalam mengendalikan patogen F. oxysporum f.sp. capsici secara in vitro. Isolat BE 12 yang bereaksi positif pada uji pendarflour memiliki pengaruh dalam menghambat pertumbuhan miselium dari jamur F. oxysporum f.sp. capsici. Hasil morfologi seluruh isolat bakteri endofit memiliki bentuk bundar berwarna putih dengan tepi koloni berbentuk rata dan berombak serta memiliki elevasi yang datar. Uji Gram bakteri menunjukkan hasil tiga dari delapan isolat bakteri endofit merupakan Gram negatif yaitu BE 2, BE 4 dan BE 12.