Cotton leafroll dwarf virus (CLRDV) is an aphid-transmitted virus recently identified across the Cotton Belt region of the U.S. Yield responses to CLRDV have been inconsistent, and asymptomatic infections can occur in which no losses are apparent. Conditions underlying the observed variation in yield responses are not understood. A three-year field study was conducted to examine whether yield loss caused by CLRDV is influenced by the age of cotton plants at the time of infection. Timing of infection was investigated by infesting caged plots of cotton with viruliferous Aphis gossypii to transmit CLRDV at different seedling growth stages, beginning after seedling emergence and continuing weekly for three to four weeks. Timing of infection impacted yield only in one out of three years suggesting that plant age is not a primary factor contributing to CLRDV-related yield loss. Future studies are needed to identify the environmental factors influencing disease severity and yield loss.
