Efficacy of Insecticides for Management of Whiteflies in Cotton

Data were collected in 2017 and 2018 to evaluate the efficacy of commonly used whitefly insecticides including pyriproxyfen (IRAC group 7c), flupyradifurone (group 4d), acetamiprid (group 4a), and buprofezin (group 16) compared to not sprayed cotton.  Whitefly pressure ranged from moderate (>5 immatures per leaf) to extreme (>100 immatures per square inch). In replicated plots, 5 leaves per plot (5th expanded leaf from top of plant)  were evaluated weekly before and after treatment to estimate efficacy in short and long term activity. Data show that all insecticides provided 2 to 4 weeks suppression under moderate conditions while buprofezin was not suitable for control under extreme pressure.  Acetamiprid and flupyradifunone provided immediate suppression, while pyriproxyfen and buprofezin were slower acting but prevented significant yield losses.  Flupyradifurone and acetamiprid consistently provided maximum yields.