Cabai merah merupakan salah satu tanaman yang banyak dibudidayakan oleh masyarakat khususnya petani baik di dataran tinggi maupun di dataran rendah. Salah satu resiko dalam budidaya tanaman cabai adalah serangan patogen. Layu Fusarium oxysporum adalah salah satu patogen yang diketahui menyerang tanaman cabai. Pengendalian yang dapat dilakukan untuk mencegah penyakit ini adalah pengendalian hayati dengan menggunakan cendawan endofit asal gulma Axonopus compressus yang tumbuh subur dipertamanan cabai merah yang terserang patogen Fusarium oxysporum. Penelitian ini dilakukan untuk menemukan cendawan endofit asal gulma Axonopus compressus yang berpotensi menekan pertumbuhan layu Fusarium oxysporum pada tanaman cabai merah secara in vitro. Penelitian ini dilaksanakan di Laboratorium Proteksi Tanaman Universitas Borneo Tarakan. Cendawan endofit diperoleh dengan cara membersihkan permukaan daun dan akar menggunakan NaOCL 1% dan alkohol 70%, kemudian dibilas dengan akuades steril dan dipotong dengan ukuran 1 cm kemudian ditanamkan pada media PDA (Potato dextros agar). Cendawan diidentifikasi secara makroskopis dan mikroskopis, kemudian di uji sifat patogenitasnya lalu dilanjutkan dengan uji kemampuan antagonis. Hasil penelitian ditemukan 34 isolat cendawan asal gulma Axonopus compressus. Dari 34 isolat hanya 2 isolat yang bersifat non patogen dan mampu menekan pertumbuhan penyakit penyakit layu Fusarium oxysporum.
Kata Kunci: Axonopus compressus, Endofit, Fusarium oxysporum

Red chili is one of plants that is widely cultivated by community, especially farmers both in the highlands and in the lowlands. One of the risks in chili cultivation is pathogen attack. The fusarium oxysporum wilt is one of the pathogens known to attack the chili plants. The control that can be done to prevent this disease is biological control by using endophytic fungi from the axonopus compressus weeds which thrive on the red chili plants attacked by the fusarium oxysporum pathogen. This research was conducted to find out the endophytic fungi from the axonopus compressus weeds which had the potential to supress the growth of fusarium oxysporum on red chili plants throught in vitro. this research was mainly conducted on the plant protection Laboratory of Borneo Tarakan University. The endophytic fungi were obtained by cleaning the surface of the leaves and roots using 1% of NaOCL and 70% of alcohol, then rinsed with sterile distilled water and cut to a size of 1 cm them implanted on PDA media (Potato Dextrose Agar). The fungi were identified macroscopically and microscopically, then tested for its pathogenicity and then continued with the antagonist ability test. The results of the research found that there were 34 isolates of fungi from the axonopus compressus weeds. There were only 2 out of 34 isolates which were non-pathogenic and able to suppress the growth of fusarium oxysporum wilt disease. Keywords: axonopus compressus, endophytic fungi, fusarium oxysporum