IDENTIFIKASI PATOGEN PENYAKIT AKAR PUTIH PADA TANAMAN CENGKEH (Syzygium aromaticum L.) DAN PENGENDALIAN SECARA HAYATI

Clove plants (Syzygium aromaticum L.) is plantation crops that have fairly high economic value. One of the diseases that attacks clove plants in Unggahan Village, Seririt District, and Busungbiu Village, Busungbiu District, Buleleng was white root disease which was first discovered in 2011. The clove plants suddenly died with symptoms showing withered leaves, dry and fall. There were white rhizomorph fungus on the roots of the plants. Various efforts were used to control and prevent the spreading of the white root disease including eradication, technical cultures and the use of synthetic chemical fungicides, but did not give a satisfactory result. It needed research on the species of white root disease pathogens and the control with natural enemies that involve microorganisms which were antagonistic to pathogens. The isolation of the white root disease pathogen from the diseased clove plants was done by in vitro followed by pathogenicity test. The observations of the clove’s roots with pathogen-infected (control) using micro technique method showed white mycelia pathogen attached on the surface of the root epidermal tissue and into the cortical tissue towards the pith tissue (pith) of the clove plant’s root in the control treatment. The pathogens were being re-isolated for the macroscopic and microscopic morphological identification and molecular identification followed by the analysis of phylogeny, resulting in getting the white root disease pathogens in clove plants which was Schizophyllum commune. The antagonistic microbes isolation from the rhizosphere of the cloves and duwet plants without symptoms of any diseases, earned 37 fungal isolates consisting of: 32 isolates of Trichoderma spp., 3 isolates of Aspergillus spp., 1 isolate of Penicillium sp. and 1 isolate of Fusarium sp. The isolates that have >80% inhibitory were used as antagonist candidates, so getting 5 (five) isolates of Trichoderma spp. namely: isolates (BK2), (BD1), (MB1), (JB1) and (LC2). The inhibitory testing of 5 isolates antagonistic candidates against the extensive colonies of the pathogens showed significantly different on the 5% extent (P