ISOLASI DAN KARAKTERISASI PENYEBAB Damping-off SEMAI Acacia mangium WILLD.

BERNIKE ARNI WARDANI, Prof. Dr. Ir. S.M. Widyastuti, M. Sc.

2007 | Skripsi | S1 KEHUTANAN

Persemaian A. mangium di RAPP (Riau Anda/an Pulp 9nd Paper) terserang damping-off Penggunaan fungi antagonis Trichodr;:rma spp. dikembangkan sebagai altematif pengendalian patogen tular tanah. Penelitian ini bertujuan untuk mengetahui penyebab damping-off semai A. mangium di RAPP dan efektivitas Trichoderma spp. dari tempat yang sama dengan a????al patogen dibanding Trichoderma spp. dari tempat yang berbeda. Trichoderma reesei (T 13) koleksi Laboratorium Perlindungan dan Kesehatan Rutan, Fakultas Kehutanan, UGM, yang telah teruji efektif dalam menghambat pertumbuhan patogen tular tanah digunakan sebagai pembanding. Prosedur penelitian yang dilakukan meliputi : (la) isolasi patogen dari semai A. mangium sakit dan sampel tanah dari RAPP, (1 b) karakterisasi patogen dengan diinkubasikan pada 4 suhu berbeda (5°C, 10°C, 28°C, dan 33°C) dan pengamatan bentuk spora, (2) isolasi fungi antagonis Trichoderma spp., (3) uji Postulat Koch pada semai A. mangium, (4) uji antagonistik Trichoderma spp. secara in vitro, dan ( 4) uji efektivitas Trichoderma spp. terhadap perkembangan fungi penyebab damping-offsecara in vivo. Dari hasil isolasi dan identifikasi dapat diketahui bahw& penyebab damping-off semai A. mangium di RAPP adalah Fusarium sp. Tiga isolat Trichoderma spp. dari RAPP yang paling efektif dalam ivenghambat pertumbuhan Fusarium F1 dan F2 secara in vitro dibandingkan dengan isolat T1 3 koleksi lab. Perlindungan dan Kesehatan Rutan yang diisolasi dari tanah di lingkungan Kampus UGM (daya hambat 73,99 %) adalah isolat T62 (96,07%), T67 (91,53%), dan T70 (87,04%). Secara in vivo, tiga isolat yang paling efektif dibandingkan dengan isolat T13 (serangan damping-off 33,33%; hid\lP 91,67%; rerata pertambahan tinggi 1,87 cm/minggu) adalah isolat T70 (0%; l00%; 2,11 cm), T71 (22%, 100%; 1,735 cm), dan T6s (22%; 83%; 1,979 cm).

A. mangium nursery in RAPP (Riau Andalan Pulp and Raper) were suffered from damping-off The using of Trichoderma spp. antagonis, fungi was expanded as a control alternative of soil-borne pathogen. The research was aimed to evaluate the damping-off pathogen of A. mangium seedling in RAPP and to compare Trichoderma spp. from the same area with the origin area of pathogen with Trichoderma spp. from the different area in their effectiveness. Trichoderma reesei (T13 ), the collection of Forest Health and Protection Laboratory, Faculty of Forestry, Gadjah Mada University that had put to a test effectively in suppressing the growth of soil-borne pathogen, was used as a comparison. The procedur research has been done, involving: l a) isolation the pathogen from infected A. mangium seedling and soil example from RAPP, 1 b) the pathogen characterization by incubation at 4 different tempera,tures (5°C, 10°C, 28°C, and 33°C) and observation the spore shape, 2) isolation of Trichoderma spp., 3) Postulat Koch test on the A. mangium seedling, 4) antagonistic test of Trichoderma spp. in vitro, and 4) effectiveness test of Trichoderma spp. against developing damping-off pathogen in vivo. The result showed that the pathogen of damping-off disease of A. mangium seedling in RAPP was Fusarium sp. The most three effective Trichoderma isolates in suppressing the growth of Fusarium sp. (FI and F2) than T 13 isolate belonged to Forest Health and Protection Laboratory colle????tion which were isolated from the soil of Gadjah Mada University area in vitro (i$bit ability was 73,99%) were T62 isolate (96,07%), T61(91,53%), and T70 (87,04%). The most three effective Trichoderma isolates than T 13 isolate in vivo (the damping-off attack was 33,33%, the living rate was 91,67%, the height growth ayerage was 1,87 cm/week) were T70 isolate (0%; 100% and 2,11cm), T71(22%; 100%, and 1,735cm), and T65(22%; 83%, and 1,979cm).

Kata Kunci : semai A. mangium, damping-off, Trichoderma spp.