Evaluation of Postemergence Fungicides and Application Method on Sugar Beet for Control of Rhizoctonia Crown and Root Rot in Northwest Minnesota, 2024

Rhizoctonia root and crown rot (RCRR), caused by Rhizoctonia solani, is the most common root disease of sugar beet in Minnesota and eastern North Dakota. Mid-late season infection of plants results in root rotwith dark brownto black lesions on the surface that are accompanied by internal rot, leading to chlorotic and wilting foliage. In this study, we evaluated the efficacy of conventional fungicides applied postemergence as a 7-in. band or as a broadcast for managing RCRR. The trial was conducted in 2024 in Crookston, MN, on a moderately susceptible sugar beet variety (Beta vulgaris ‘Crystal 793RR’). Results from this trial will help sugar beet growers inmaking informed decisions about managing this disease.