UJI INFEKTIVITAS Scleroderma spp. PADA SEMAI Shoreaselarrica (DC.) Blume DAN Hopea odorata (Roxb.)ABSTRACT 1Infection test of Scleroderma geaster, Scleroderma sirmamariense, Sclerodermacolumnare and Scleroderma sp. to Shorea selanica seedlings has been studied undergreen house conditions. Those myconhizal lirngi, except Scleroderma sp. were alsotested to Hopea odorara seedlings. Root mycorrhizal percentage and formation ofmantel and Hartigfs net structures were investigated.The objective of the research was to find out the most infective Sclerodermamycorrhizal iimgi to Shorea selanica and Hopea odorara seedlings._ Root structural analysis of 3 months inoculated roots showed that there weremycorrhizal colonization in Shorea selanica and Hopea odoraia rooting system butmantel and I-Iartig?s net structures were not formed yet. These structures werecompletely fonned 4 months after inoculation. Root structure observation showed thatScleroderma spp. colonized and infected well the root system of Shorea selarzica andHopea odorara seedlings. The percentage of mycorrhizal roots was 13.75 % to 42.50 %for Shorea selanica seedlings and 14.17 % to 59.17 % for Hopea odorata. Hartig?s netstructures were formed in between two radially elongated epidermis cells.PENDAHULUANTanaman meranti (Dqoterocarpaceae) merupakan salah satu pohon hutan tropisyang mutlak rnembutuhkan mikoriza terutama pada tingkat semai (Yasman, 1997).Mikoriza adalah suatu asosiasi yang sepenuhnya simbiosis dan menghasilkan suatu sifatmorfologi yang baru dan konsisten dalam proses asosiasinya serta mendatangkankcuntungan untuk lcedua organisme tersebut (Harley & Smith, 1983). Sclerodermaspp. mempakan cendawan elctomikoriza yang sexing ditemukan berasosiasi dengan jenis-jenis tanaman dan famili Dipterocarpaceae, Pinaceae dan Gnetaceae. Sifat khusus dariektomikoriza adalah adanya struktur mantel yang terbcntuk dad jalinan hifa, yangmenetap pada permukaan akar dan Hartig-net yang terdapat di antara sel epidermis dan1