Abstract
Blast is recognized as one of the most devastating diseases of rice in the world (Savary et al., 2000). The disease is caused by the fungus Pyricularia oryzae (synonym Magnaporthe oryzae). This model pathosystem for research on host-pathogen interactions (Dean et al., 2012) is also a major challenge for food security (Pennisi, 2010). P. oryzae is an ascomycete fungus that reproduces mainly by asexual multiplication. This widely described asexual cycle is the only mode of reproduction observed in nature. The cycle starts with the adhesion of a spore to the leaf, followed very quickly (in less than 2 h) by the formation of a germ tube. The appressorium formed at the tip of the germ tube allows penetration into the plant cell. One to 2 weeks after infection, P. oryzae is able to sporulate and start a new cycle