Isolation and Characterisation of Some Endophytic Bacteria from Papua New Guinea Sugarcane

Endophytic bacteria were isolated from the stalks of sugarcane, Saccharum officinarum, growing in Papua New Guinea. Endophytic bacterial communities from extracted juice averaged 6x 10 cfu/ml, which is 25 times greater than the number of endophytic bacteria found in commercial varieties in South Africa. Sixty isolates, representing the different colony morphology types, were used for in vitro inhibition tests against Clavibacter michiganensis subsp. insidiosus (a relative of the causative agent of ratoon stunting disease), Fusarium napiforme, F. proliferatum and Ustilago scitaminea (smut). None of the isolates showed inhibition of Fusarium. Thirteen belonged to the genus Burkholderia, as shown by 16S sequencing; among these, four inhibited the growth of Ustilago scitaminea and seven inhibited the growth of Clavibacter michiganensis. Six of the Burkholderia isolates showed strong chitinase activity.