Population genomics of the maize anthracnose pathogen Colletotrichum graminicola using restriction site-associated DNA sequencing and whole-genome sequencing (WGS)

Plant pathogens cause significant reductions in yield and crop quality and cause enormous economic losses worldwide. Reducing these losses provide an obvious strategy to increase food production without further degrading natural ecosystems but this requires knowledge about the biology and evolution of the pathogens in agroecosystems. We employed a population genomics approach to investigate the genetic diversity and reproductive biology of the maize anthracnose pathogen (Colletotrichum graminicola) in 14 countries. We found that the populations are correlated their geographical origin and migration between countries is ongoing, possibly caused by the movement of infected plant material. This result has direct implications on disease management since migration can cause the movement of more virulent and/or fungicide resistant genotypes. We conclude that genetic recombination is frequent (in contrast to the traditional view of C. graminicola being mainly asexual), which strongly impacts control measures and breeding programs aimed at controlling this disease.