For efficient molecular detection of the Philippine banana strains of Ralstonia solanacearum in soil, 16 procedures based on four methodologies for direct DNA isolation from soil were evaluated for their applicability in generating amplifiable template for polymerase chain reaction. The efficiency of the DNA recovery by using each method was assessed by amplification of M114, a repetitive element specific for the Philippine banana strains of R. solanacearum .Among the protocols used, the modified alkaline extraction method and the use of the MoBio kit for isolating DNA were able to produce the M114 amplicon consistently. The modified alkaline lysis procedure had a sensitivity level of 10⁵ CFU/g soil. 

Key words: DNA isolation, detection, Ralstonia solanacearum, PCR, sensitivity level