Cotton leafroll dwarf disease, caused by Cotton leafroll dwarf virus (CLRDV), was first detected in the United States in Alabama in 2017. Historically, CLRDV has been associated with cotton blue disease and was first described in Africa in 1949. CLRDV is transmitted by the cotton aphid (Aphis gossypii) and has been reported to cause yield losses of up to 80% in South America. The CLRDV sentinel plot program and working group was organized to monitor CLRDV and support collaborative efforts across the southern U.S. Cotton Belt. Sentinel plot results from 2019 to 2021 demonstrate that CLRDV is now widespread throughout Alabama and the southern U.S. Cotton Belt. CLRDV is difficult to identify based on symptoms alone, which can vary throughout the season and by variety and region. Symptoms include stunted plants, leaf distortion, leaf rugosity, vein discoloration, late summer leaf reddening and bronzing, red stems, node stacking, and accentuated verticality. Sentinel plot results also reveal that CLRDV incidence varies by location, variety, and planting date. Management recommendations focus on cotton stalk destruction, winter weed burn down, and planting early.
