Inventarisasi dan Identifikasi Patogen Tular-tanah pada Pertanaman Kentang di Kabupaten Purbalingga

atogen tular-tanah di lahan kentang merupakan salah satu faktor penting yang berpengaruh terhadap pertumbuhan, produksi, dan kualitas hasil tanaman. Inventarisasi dan identifikasi patogen tular-tanah di lahan kentang dengan metode purposive sampling telah dilakukan di Kabupaten Purbalingga, yang meliputi Dusun Gunung Malang di Desa Serang dan Dusun Bambangan dan Kutabawa di Desa Kutabawa Kecamatan Karangreja dari bulan November 2008 sampai Januari 2009. Penelitian bertujuan untuk mengetahui jenis dan virulensi patogen tular-tanah di lahan kentang di lokasi tersebut. Isolasi dan uji virulensi dilaksanakan di Laboratorium Mikrobiologi, Fakultas Pertanian, Universitas Jenderal Soedirman, Purwokerto. Peubah yang diamati yaitu karakter morfologi mikrobe patogen, kepadatan di dalam tanah, dan reaksi hipersensitif. Hasil penelitian menunjukkan bahwa tujuh spesies patogen ditemukan di lahan kentang, yaitu Fusarium oxysporum, F. solani, Ralstonia solanacearum, Curvularia sp., Phytophthora infestans, Helminthosporium purpureum, dan Pseudomonas kelompok berpendar. Populasi mikrobe di lahan kentang yang paling dominan ialah R. solanacearum, yaitu 71,6%, disusul oleh F. oxysporum sebesar 16,87%. Sebaran mikrobe di masing-masing lahan kentang berbeda. Semua lahan kentang di Kabupaten Purbalingga sudah terkontaminasi patogen tular-tanah penting sehingga perlu disehatkan kembali secara hayati.Soilborne plant pathogens in potato land are one of important factors influencing plant growth, production and yield quality. Inventarization and identification of soilborne diseases using purposive sampling method were conducted at potato land in Purbalingga Regency consisted of Guning Malang location at Serang Village and Bambangan and Kutabawa locations at Kutabawa Village, Karangreja District from November 2008 to January 2009. The study aimed to determine type and virulence of soilborne pathogens at the locations. Isolation and virulence test were carried out at the Laboratory of Microbiology, Faculty of Agriculture, Jenderal Soedirman University, Purwokerto. Variable observed in the research was morphological characteristics of pathogenic microbes, their density in soils, and response of hypersensitive test. Result of the research showed that seven pathogenic species were found at the land, i.e., Fusarium oxysporum, F. solani, Ralstonia solanacearum, Curvularia sp., Phytophthora infestans, Helminthosporium purpureum, and fluorescent Pseudomonad. The dominant microbe population in potato land was R. solanacearum with 71.6% followed by F. oxysporum with 16.87%. The microbes were spread differently in every potato land. All potato lands in Purbalingga Regency have been contaminated by the important potato pathogens so that soil bioremediation is needed