Phytophthora

Phytophthora (from Greek ("phytón"), "plant" and (); means "the plant-destroyer". It is a genus of plant-damaging oomycetes (water molds). 
They can cause enormous economic losses on crops, and damage in natural ecosystems. The cell wall of "Phytophthora" is made of cellulose. The genus was first described by Heinrich Anton de Bary in 1875. About 170 species have been described, though there are many more undescribed.