Greenhouse Whitefly Control of Potted Chrysanthemums, Massachusetts, 1984

Seven insecticides were tested for efficacy against greenhouse whitefly and for phytotoxic responses on chrysanthemums. Plants were grown in 4 inch pots using 50% MetroMix 350 and 50% sterilized field soil. The plants were pinched on 24 Oct. Flower buds began showing during the third week of November. Each insecticide was applied with a 2-qt capacity hand pump sprayer to the upper and lower leaf surfaces of 3 plants, which were then placed randomly on benches. Applications were made on 15 Oct and again on 14 Nov. Whitefly populations were measured by inspecting one intermediate leaf per plant and counting the adults and immatures present.