Surface hydrophobicity and surface rigidity induce spore germination in Colletotrichum graminicola

We investigated the relationship between physical characteristics of artifi cial surfaces, spore attachment, and spore germination in Colletotrichum gr aminicola. Surface hydrophobicity and surface rigidity were both signals fo r breaking dormancy and initiating spore germination, but spore attachment atone was not an important inducing signal. The presence of a carbon source overrode the necessity for a rigid, hydrophobic substrate for spore germin ation. Spore attachment was typically stronger to more hydrophobic surfaces , but certain hydrophilic surfaces also proved to be good substrates for sp ore attachment. In contrast to spore germination, appressorial induction wa s more dependent on attachment to a rigid substrate than it was on surface hydrophobicity. Appressoria were induced efficiently on hydrophilic surface s, as long as there was significant conidial attachment to those surfaces.