Adhesion of ungerminated Colletotrichum musae conidia

Abstract Conidia of Colletotrichum musae adhered to a greater extent on hydrophobic than on hydrophilic substrata. Polystyrene was chosen as a model substratum to study adhesion of conidia since surface hydrophobicity on polystyrene and the banana fruit was similar and conidia adhered equally well to both surfaces. Conidia adhered several hours before germ tubes emerged. On polystyrene, 47% and 94% of the conidia adhered when incubated for 2 h at 1 and 24 °C, respectively. After 4 h at either temperature, > 84% conidia adhered. Concentrations of Triton X-100 and SDS which did not affect spore viability inhibited adhesion. Conidia were relatively non-adhesive when killed with heat, formaldehyde, or UV light. Conidia incubated with the proteolytic enzyme pronase E adhered significantly less than controls. Conidia that were treated with pronase E and then washed regained adhesiveness, suggesting that cell-surface protein(s) are involved in adhesion of conidia and that the adhesive material can be produced at more than one time prior to germ tube emergence.