Isolasi, Identifikasi, dan Karakterisasi Jamur Entomopatogen dari Rizosfir Pertanaman Kubis

Tujuan penelitian adalah mengidentifikasi dan mengkarakterisasi jamur entomopatogen dari rizosfirpertanaman kubis. Percobaan ini dilaksanakan di Laboratorium Entomologi dan Penyakit Tumbuhan, FakultasPertanian Universitas Andalas dan Laboratorium Entomologi, Balai Penelitian Tanaman Buah Tropika Solok dariMaret sampai Agustus 2006. Pengujian sporulasi jamur entomopatogen menggunakan rancangan acak lengkap polafaktorial dengan 2 faktor yaitu jenis isolat dan substrat. Sebanyak 500 g tanah diambil dari pertanaman kubis di PadangPanjang (Desa Koto Panjang) dan Alahan Panjang (Desa Rimbo Data) kemudian dimasukkan ke dalam kotak plastik.Sebanyak 10 ekor Tenebrio molitor stadia larva instar ketiga yang baru berganti kulit dimasukkan ke dalam kotakyang berisi tanah, kemudian ditutup dengan selapis tipis tanah dan dilembabkan dengan menyemprotkan akuadessteril di atasnya sebanyak 100-150 ml. Kotak tersebut diletakkan di laboratorium dengan kelembaban >90%. Larvayang terinfeksi setelah 3-4 hari digunakan sebagai sumber isolat jamur entomopatogen. Hasil penelitian menunjukkanbahwa jamur yang menginfeksi T. molitor adalah jamur entomopatogen yang dapat menyebabkan kematian hamakrop kubis Crocidolomia pavonana F.. Enam jenis jamur patogen serangga berhasil dibiakkan pada media SDAY.Genus jamur patogen tersebut adalah Fusarium sp., Beauveria sp., Metarhizium sp., Nomuraea sp., Paecilomycessp., dan Achersonia sp.. Beras dan gandum adalah substrat yang paling baik bagi perbanyakan dan pertumbuhankoloni jamur dibandingkan substrat lainnya. Hasil penelitian ini membuktikan bahwa spesies jamur entomopatogentersebar secara alami di lingkungan kebun tanaman kubis.ABSTRACT. Nuraida and A. Hasyim. 2009. Isolation, Identification, and Characterization of EntomopathogenicFungi from Rhizosphere of Cabbage Plant. This experiment was conducted at Entomology and PhytopathologyLaboratory Faculty of Agriculture, Andalas University and Entomology Laboratory of Tropical Fruit ResearchInstitute, Solok, West Sumatera, from March to August 2006. A factorial completely randomized design with 2factors, i.e. fungi isolates and its substrates was applied. About 500 g soil samples were collected from cabbagefields in Padang Panjang (Koto Panjang Village) and Alahan Panjang (Rimbo Data Village) and placed into plasticbags. The soils were screened for the presence of entomopathogenic fungi. The new third instars larvas of Tenebriomolitor L. were used as baits. About 10 larvae were placed on the soil surface in plastic bowl and covered withlid. Then the bowl was incubated under laboratory condition with >90% RH. The infected larvas, after 3-4 days,were used as source of entomopathogenic fungi isolate. The results showed that fungi isolated from T. molitor baitwere all entomopathogenic causing mortality of Crocidolomia pavonana. Six entomopathogens were successfullycultured on SDAY. These were Fusarium sp., Beauveria sp., Metarhizium sp., Nomuraea sp., Paecilomyces sp., andAchersonia sp.. Rice and wheat produced better cultures and growth of fungal colony than those other substrates.The present study has provided strong evidence that entomopathogenic fungal species were naturally spread in thesoil environment of cabbage field