Estimation of spore dispersal kernel in Mycosphaerella Fijiensis from one-generation disease gradients

We report two field experiments aiming to independently measure dispersal distances of both sexual and asexual spores of the devastating wind-dispersed banana plant pathogen fungus Mycosphaerella fijiensis .Disease gradients were assessed during a single generation of the pathogen and over a large number of traps installed up to 1000 m along eight directions radiating from a traceable source of inoculum com posed of QoI-resistant strains. Ascospores dispersed at an average distance of 160 m and their dispersal kernel displayed a heavy tail with both a steep gradient in the first few metres of each direct ion and rare long-distance dispersal (LDD) events up to 1000 m from the source. Conidia dispersed at an average distance of 4 m according to a thin-tailed kernel with no LDD since no conidia were trapped over 12,5 m. (Résumé d'auteur