The infection process and the number of conidia and hyphae in banana roots at the early infection stage. At 27 h post inoculation (hpi), conidia and hyphae of the GFP-expressing Foc TR4 were observed in the vascular tissue of BX (a) and NK (b) banana. At 51 hpi, more conidia and hyphae were found in BX (c) and NK (d) compared to the fungal presence at 27 hpi (e) The number of conidia or hyphae in roots under laser confocal microscope. BX: the infected BX roots, NK: the infected NK roots. A total of 60–80 root transverse sections were counted for every treatment samples for three replications. The error bars represent SE. Asterisks indicate significantly difference (* P < 0.05) through Student’s test.