Phymatotrichopsis Root Rot of Grape

Phymatotrichopsis root rot of grape (PRR) is commonly known as cotton root rot, Texas root rot or Phymatotrichum root rot.  PRR is a destructive disease of many economic crops including wine grape grown in calcareous clay soils with a high pH range of 7.0 – 8.5 in central and southern Arizona. Significant number of vine losses to PRR occur annually in many vineyards in Cochise, Santa Cruz, and Yavapai counties.