Characterization of the Potato Late Blight Pathogen Phytophthora infestans in Tunisia

This mini-review focus on summarizing different phenotypic and genotypic analysis recorded on Phytophthora infestans population collected from the Northern area of Tunisia. Here, we demonstrated that mating type distribution plays a primordial role in genetic structure of the pathogen between sampling regions. Also, a probably strong correlation between mating type and metalaxyl resistance could be mentioned. Next to that, we found that the aggressiveness and the virulence patterns were highly effective parameters to outline phenotypic diversity in Tunisian population that showed specific characteristics comparing with Algeria and others countries in the world. Consistently, genotypic diversity based on SSR markers seems to be a very interesting key in the genetic understanding of the pathogen. In fact, we found that P. infestans populations in Tunisia were divided to two major phylogenic groups: a clonal lineage group shared between all sampling regions and a diverse group detected in potato population and specific to two sub-regions. Thus, we could conclude that genotypic diversity confirmed phenotypic diversity and both analysis leaded us to conclude that population structure of P. infestans in Tunisia is very specific either in North African area or all over the world. _____________________________________________________________________________________________________________