Genetic diversity and population structure of Moroccan Botrytis spp. strains, causing chocolate spot disease in faba bean

Chocolate spot (Botrytis spp.) is one of the most important foliar diseases limiting the yield and seed quality of faba bean (Vicia faba L.) worldwide. Knowledge of the population structure of the pathogen is key to developing appropriate breeding strategies for disease management. This study aims to assess the genetic diversity and population structure of 75 Botrytis spp. isolates collected from seven major faba bean growing regions in Morocco. Genetic diversity was assessed using 30 Sequence Related Amplified Polymorphism (SRAP) primer combinations. Eight primer-combinations generated 118 polymorphic alleles and had discriminated between different isolates with an average PIC value of 0.28. The Moroccan Botrytis spp. populations presented a high genetic diversity that was more distributed within populations (99%) than among populations. Population structure analysis revealed that the genetic diversity was not linked to geographic locations, indicating limited geographic delimitation and significant gene flow. The data will be useful to improve the faba bean breeding program to develop effective resistant cultivars. To our knowledge, this is the first study carried out on the genetic variability of Botrytis spp. Isolates from faba bean In Morocco.