Comparison of the colonization of Fusarium oxysporum f. sp. cubense tropical race 4 on the lateral roots of banana cv ‘Brazilian’ (susceptible wild-type) and cv ‘Nongke No 1’ (resistant mutant). Few chlamydospores attached and germinated on the roots of cv ‘Nongke No 1’ at 48 hai (A) and 96 hai (B), respectively. Significant attachment and germination of spores of chlamydospores on the surface of the lateral roots of cv ‘Brazilian’ at 48 hai (C) and 96 hai (D) respectively; A-D. Scale bar = 50 μm.