Gene flow analysis from transgenic plants to F. oxysporum (V5W2-9 NH3). Plant colonisation was low with only 40 root segments colonised by the fungus. A total 36 fungi grew on normal media of which 20 where from the transgenic plants and 16 from the controls. Four (4) fungi established on selection media of which 3 were from the controls and only one established from the transgenic plants. Overall, F. oxysporum colonisation averaged 27.3% in transgenic plants and 20.5% in the non-transgenic plants. Plant colonisation by F. oxysporum (V5W2-9 NH3) was significantly influenced by the banana genotype (P ≤ 0.034) (Table 1). Although there was no effect of sampling time on colonisation (P = 0.076) among plants of the same genotype, plant colonisation was significantly affected by the media composition (P ≤ 0.0001), with higher percentage colonisation observed for roots that were plated on non-selective media compared to those that were plated on selective media (P ≤ 0.025) (Table 1). There