Through the incubation period of dual cultures we see a change of the A. alternata colony look. From the beginning of incubation, there is obvious discoloring in diffusible metabolites (in volatile this is later noticeable), and a loss of sporulation.
Microscopic observations of the pathogen after the interval of incubation, from both of dual colonies cases showed deformations of hyphae, which exhibit a longer distance between septa and have empty ends. There is a small number or absence of conidia than in the check (Figures 17-19)..