Book Announcements

The results of our experiments suggest that toxin(s) of Mycosphaerella fijiensis would be involved neither in infection initiation, nor in the hypersensitive reaction in highly resistant cultivars but could serve at most as secondary determinant of the pathogenicity, contributing to the lesion expansion in cultivars exhibiting partial resistance to Black Leaf Streak disease. Moreover, the effects of toxin(s) on chlorophyll fluorescence, as well as preliminary electron microscopy observation, suggest that chloroplasts could be a precocious site of action of the toxin(s). Therefore, in vitro heterotrophic tissues would not be a suitable target to perform the screening with such toxin(s). The prospects and limitations of M. fijiensis toxin(s) for screening banana for resistance to Black Sigatoka are highlighted. This revised version was published online in July 2006 with corrections to the Cover Date.