Evaluation of Insecticide Residues on the Mortality of Adult Glassy-winged Sharpshooter on Citrus, 2013 *

During 2013, 35 young potted citrus trees were organized in a CRD with 5 replicates of 7 treatments to evaluate the effects of insecticide residues on the mortality of glassy-winged sharpshooter (GWSS). On 3 October, a squirt bottle was used to spray each tree with 160 ml (runoff) of insecticide solutions that were prepared according to the per acre use rate and water volumes indicated in Table 1 . Once residues were dried, a 5-gal paint strainer bag containing 10 adult GWSS was placed over the foliage of each tree. After 7 d of exposure, GWSS mortality was evaluated on 10 October. This process was repeated weekly with new GWSS placed in bags on the trees on 10 October, 17 October, 24 October and 31 October and removed and evaluated for mortality 7 d later. Data were evaluated by analysis of variance with means separated by Fisher’s Protected LSD ( P  = 0.05).

All treatments except Pyganic + oil provided significantly higher mortality through 31 October compared with the water check ( Table 1 ). Danitol and Actara 4 fl oz treatments resulted in higher mortality compared with the water check on all evaluation dates. The residual effects of the 4 oz rate of Actara in 200 gpa of water (the concentration typically used for Asian citrus psyllid) were greater than the residual effects of the 5.5 oz rate of Actara in 500 gpa of water (the concentration and water volume typically used for Fuller rose beetle) on the last evaluation date (7 November).

Author notes