First Report of Race 1 and Race 2 Causing Aphanomyces Root Rot on Alfalfa () in South Dakota.

causes Aphanomyces root rot (ARR) in alfalfa (), along with root rot on many other legumes, including pea, clover, and lentil (Malvick et al., 2009). In 2020, South Dakota (SD) planted the most acres of alfalfa in the United States, which demonstrates the importance of alfalfa to the state.