Morphological Characterization of Colletotrichum

Morphological examinations focused on the colony characteristics, acervuli, conidiophores, conidiogenous cells, conidia, setae, appressoria, ascomata, asci, and ascospores of representative isolates that were randomly selected from each Colletotrichum species. Mycelial plugs (5 mm diam) from the margin of cultures were transferred to PDA and incubated at 25 °C in the dark. Colony characteristics were photographed with a Canon EOS M50 Mark II camera after 4 d, and colony diameters were measured daily to calculate the mycelial growth rates (mm/d). In order to induce appressorium formation, 10 µL of conidial suspension (10⁶ conidia/mL) was placed on a slide, placed inside plates containing a piece of moistened filter paper with sterile water, and then incubated at 25 °C in dark [77 (link)]. Measurements and morphological descriptions of acervuli, conidiophores, conidiogenous cells, conidia, setae, appressoria, ascomata, asci, and ascospores of the representative isolates were observed using a Zeiss Axio Imager A2m microscope (Carl Zeiss Microscopy, Oberkochen, Germany). Fifty individuals of per structure were measured for each isolate.