Pengaruh Metode Sterilisasi dan Konsentrasi Filtrat Bakteri Endofit untuk mengendalikan Penyakit Blendok (Xanthomonas albilineans (Ashby) Savulescu 1947) pada Tanaman Tebu di Rumah Kaca

Abstract

Leaf scald (Xanthomonas albilineans) is an important pathogen of sugar cane in Indonesia and cause significant losses at several main sugarcane plantation. Some control measures, e.i. bactericides, smeared lysol 20% or alcohol 70% on cutting knife seedling for disinfectant, and hot water treatment at 50 minutes on 52,5°C, have not given satisfactory result in managing this leaf scald in sugarcane on the field. Biological control with filtrate of endophyts bacterial were alternative to bio control agents Xanthomonas albilineans. The objectives of this research were to determine: influence of sterilization methods and endophytic bacterial filtrate dosages to control leaf scald (Xanthomonas albilinear) on sugar cane in green house. This research was conducted in Pyhtopathology Laboratory and green house at Faculty of Agriculture University of North Sumatra from April until December 2014. This research had done with Completely Randomized Design (CRD) with three factor: 1. type of endophytic bacteria filtrates: filtrate of B9, B7 and B2. Sterilization methods of endophytic bacterial filtrate: control (no sterilization), Sterilization by autoclave and Sterilization by filter membrane, 3. Dosage of endophytic filtrate with four level: 0,1%, 0,01%, 0,001% and 0,0001%. The result showed: 10 isolate endophytic bacteria had exploration were: B1, B2, B3, B4, B5, B6, B7, B8, B9, dan B10. Three isolate had clear zone on petridish ≥ 20 mm in vitro testing is B9, B7 and B2.The results showed that the membrane filter sterilization method was better when compared to autoclave sterilization, namely: the highest inhibitory zone diameter of endophytic bacteria in the treatment of B9 filtrate with a membrane filter sterilization method 0, 1 % at 3 day after inoculation that was equal to 23.00 mm, the percentage disease incidence in the treatment of B9 filtrate with a membrane filter sterilization method 0.0001 % - 0,1 % 33,33%. The endophytic bacteria could increase the rate of increase in the number of leaves, plant height and diameter had the highest root dry weight in the treatment of B9 in the filtrate without sterilization methods (control) concentration of 0.001% had both wet and dry weight of the roots of the highest in sugarcane 8 week after aplication at green house. Bacteria B9, B7, and B2 potential as biological agents.