Complex sentence: Montagne is remembered for pioneer research of mycological species native to Guyane, and in 1845 was the first scientist to provide a description of "Phytophthora infestans", a potato blight fungus he referred to as "Botrytis infestans".
Split into simpler sentences: Montagne is remembered for pioneer research of mycological species native to Guyane. In 1845 he was the first scientist to provide a description of "Phytophthora infestans", a potato blight fungus he referred to as "Botrytis infestans".