Isolasi dan Uji Antagonis Bakteri Endofit Akar dan Daun Kelapa Sawit (Elaeis guineensis Jacq.) terhadap Ganoderma boninense Pat.

Abstract

A study of the antagonistic of endophytic bacteria isolated from roots and leaves of palm oil (Elaeis guineensis Jacq.) againts Ganoderma boninense Pat. has been done from July 2007 to January 2008 at Microbiology Laboratory FMIPA USU Medan. Endophytic bacteria were isolated from palm oil roots and leaves of 6 plantations in Sumatera Utara. The results showed 40 different bacterial types consisting of 28 bacterial types from roots and 12 bacterial types from leaves, which were 11 isolates from Tanah Jawa, Pematang Siantar, and few isolates were found from PTPN III Rantau Prapat Utara, Labuhan Batu County and Islamic Centre Medan plantation, with 4 isolates each. Gram staining showed that as many as 22.5% were Gram positive and 77.5% were Gram negative. Almost all isolates had potential to inhibit the mycelium of G. boninense, and 3 isolates showed its ability well in inhibit the mycelium of G. boninense by result the inhibit zone. The isolates were PS34A, PS35A and PS38D. The isolates inhibited the growth of G. boninense with the length of inhibited mycelium is bigger than concentration of ketoconazole 0.09 mg/ml and 0.3 mg/ml, and smaller than 0.6 mg/ml, that was PS34A and PS35A inhibited as many as 7.8 mm, and PS38D inhibited as many as 9.8 mm. Whereas the concentration of ketoconazole 0.09 mg/ml and 0.3 mg/ml inhibited as many as 6.8 mm and 0.6 mg/ml inhibited as many as 12 mm.