Le phénomène du bleuissement chez les diatomées

A biological fact, which seemed to have a limited impact, has turned into a wider phenomenon since our experimental studies. In a critical review written by one of us (1), we had already demonstrated that the turning blue of Navicula ostrearia could not be considered as a property specific to this individual. In a dissertation (2), Hinard names other oyster bottom diatoms, less numerous than Navicula ostrearia, but showing a blue pigment as well (Storoneis crucigerum, Amphiprora paludosa). A few years ago, one of us, in collaboration with A. Jouvent (3) showed that, in specific environmental condition, some marine diatoms, belonging to other genera than Navicula (Nitzschia, Grammatophora) show this blue pigmentation phenomenon. Moreover, our unpublished experiments, carried out in collaboration with N. Lucciardi, on some fresh water diatoms lead to the same results.