Isolasi Fusarium sp. dari Sampel Tanah Belitung dan Pengujian Penghambatannya oleh Bakteri Penghasil Biosurfaktan

Abstract

Fusarium merupakan cendawan patogen yang menyebabkan penyakit pada tanaman pangan. Penggunaan pestisida sintetik berlebihan untuk menangani penyakit pada tanaman dapat menyebabkan gangguan lingkungan, sehingga dibutuhkan agen pengendali hayati berupa mikroorganisme pengendali patogen. Penelitian ini bertujuan mengisolasi Fusarium sp. yang berasal dari sampel tanah Belitung dan menguji kemampuan bakteri penghasil biosurfaktan asal Belitung dalam menghambat pertumbuhan Fusarium sp. Hasil isolasi Fusarium sp. memiliki karakteristik koloni bundar, berwarna putih, memiliki hifa bersekat serta memiliki makrokonidia dan mikrokonida. Terdapat delapan dari 16 isolat bakteri mampu menghambat Fusarium sp. dengan kemampuannya menghasilkan biosurfaktan. Koloni kedelapan isolat bakteri berwarna putih bening, berbentuk irregular, elevasi umbonate, flat dan convex, serta tepi koloni entire, undulate dan rhizoid. Kedelapan isolat bakteri merupakan bakteri Gram positif dan berbentuk basil. Berdasarkan uji drop collapse, uji oil displacement, dan uji indeks emulfikasi kedelapan isolat bakteri memiliki kemampuan menghasilkan biosurfaktan. Hasil uji hemolisis menunjukkan tujuh dari delapan isolat memiliki kemampuan menghasilkan biosurfaktan. Isolat terbaik BP2.1.3 dengan kemampuannya menghasilkan biosurfaktan dapat diaplikasikan ke tanaman untuk mengendalikan cendawan patogen.

Fusarium is a pathogenic fungus that causes disease in food plants. Excessive use of synthetic pesticides to treat plant diseases can cause environmental disturbances, so biological control agents in the form of pathogenic control microorganisms are needed. This research aims to isolation Fusarium sp. from Belitung soil samples and test the ability of biosurfactant-producing bacteria from Belitung to inhibit the growth of Fusarium sp. The results of the isolation of Fusarium sp. have the characteristics colonies were round, white in color, have septate hyphae and have macroconidia and microconidia. There were eight out of 16 bacterial isolates that were able to inhibit Fusarium sp. with its ability to produce biosurfactants. The isolated colonies were clear white, irregular in shape, elevation umbunate, flat and convex, and the margin colony is entire, undulate, and rhizoid. The eight bacterial isolates were Gram positive bacteria and were in the form of bacilli. Based on the drop collapse test, oil displacement test, and emulfication index test, the eight bacterial isolates have the ability to produce biosurfactants. The results of the hemolysis test showed that seven out of eight isolates have the ability to produce biosurfactants. The best isolate BP2.1.3 with its ability to produce biosurfactants can be applied to plants to control pathogenic fungi.