EFEKTIVITAS ISOLAT MIKROBA ANTAGONIS SEBAGAI BIOKONTROL UNTUK IDENTIFIKASI KETERJADIAN PENYAKIT BUSUK PANGKAL BATANG PADA TANAMAN KELAPA SAWIT (Elaeis guineensis Jacq.)

Penyakit busuk pangkal batang (BPB) merupakan salah satu penyakit serius pada tanaman kelapa sawit (Elaeis guineensis Jacq.) yang disebabkan oleh jamur patogen tular tanah Ganoderma boninense. Penggunaan Agen pengendali hayati merupakan salah satu cara untuk mencegah penyakit tersebut. Tujuan dari penelitian ini adalah mendapatkan mikroba endofit yang dapat menghambat pertumbuhan Ganoderma boninense. Penelitian ini dilakukan di Laboratorium Agromikrobiologi, BPPT, Serpong pada bulan Desember 2015 sampai dengan bulan November 2016. Metode yang digunakan adalah eksperimen dengan desain Rancangan Acak Lengkap. Pengujian dibagi menjadi tiga tahapan, yaitu (1) Pengujian aktivitas bakteri antagonis terhadap Ganoderma boninense secara in vitro. (2) Uji aktivitas enzim kitinase dan selulase pada isolat bakteri secara in vitro. (3) Pengujian efektivitas isolat bakteri antagonis terhadap Ganoderma boninense di rumah kaca dan membandingkannya dengan Trichoderma sp.. Parameter yang diamati pada pengujian in vivo berupa tinggi tanaman, jumlah daun, dan jumlah klorofil; keterjadian dan keparahan penyakit dengan menggunakan skala linear. Data diolah menggunakan ANOVA dua arah, dilanjutkan dengan uji DMRT (Duncan Multiple Range Test) pada taraf 5%. Pengamatan setelah 18 minggu pasca tanam menunjukan bahwa penggunaan Agen hayati dapat meningkatkan pertumbuhan tanaman kelapa sawit terutama pada jumlah daun dan jumlah klorofil. Penggunaan Isolat Trichoderma sp. Mampu menekan keterjadian penyakit Busuk Pangkal Batang dengan jumlah keterjadian sebesar 7%. The stem rot disease is a destructive disease found in plant oil palm (Elaeis guineensis Jacq.). This disease is caused by Ganoderma boninense, the soil borne pathogenic fungi that attacks the plant vessels. Efforts has been done to minimize this disease such as by utilizing the antagonist endophytic microbes which can prevent Ganoderma boninense occurence. The purpose of this study is to get endophytic microbes that can inhibit the growth of Ganoderma boninense. The research was conducted at Agromicrobiology Laboratory, BPPT, Serpong in December 2015 until November 2016. The method used in this study was experimental with completely randomized design. The test is divided into three stages, (1) Determining the in vitro activity of the antagonistic bacteria against Ganoderma boninense with dual culture method. (2) Determining the in vitro activity of the Chitinase and Celulose enzyme on bacterial isolates using chitin media. (3) Determining the in vivo effectiveness of antagonistic bacterial isolates against Ganoderma boninense compared with Trichoderma sp.. The parameters were observed in the in vivo assay is the plant height, and the number of chlorophyll.. The occurrence and severity of the disease was also observed using a linear scale. The data were processed using two-way ANOVA, followed by DMRT (Duncan Multiple Range Test) at 5% level. Result shows that the biocontrol have good results in increasing the amount of chlorophyll in the leaves of palm oil, while Trichoderma sp. both enhancing the growth of plant height and number of leaves. The result after 18 weeks planted in green house showed that the use of biological agent can increase the growth of palm oil such as the amount of leaf and chlorophyll. The use of Trichoderma sp. Isolates can suppress the occurance of stem rot disease at 7%