|Ludwig, Scott - TEXAS A&M UNIVERSITY|
Submitted to: Bemisia International Workshop Proceedings
Publication Type: Abstract Only
Publication Acceptance Date: October 6, 2006
Publication Date: December 3, 2006
Citation: Ludwig, S.W., McKenzie, C.L. 2006. Impact of insecticide residue on Bemisia tabaci (B-Biotype) [abstract]. Bemisia International Workshop Proceedings. Technical Abstract: In 2005, the Q-biotype of Bemisia tabaci was identified in the United States. This find and increased problems with management of the B-biotype of Bemisia tabaci have resulted in a national effort to develop a comprehensive management plan for whiteflies on ornamental crops. The objective of the following study is to evaluate the activity of insecticide residue against silverleaf whiteflies to aid in the development of a whitefly resistance management program. Data were transformed using an arcsine transformation prior to analysis. Data were analyzed with ANOVA and means separation was accomplished by using the least significant difference test (LSD) at the P<0.05 level. All data are presented as original means. No insecticide provided greater that 70% direct adult mortality (Table 1). Distance provided 100% control of the resulting generation on all sample dates (Table 2). Judo provided greater than 80% control of the resulting generation on all sample dates. Avid provided greater than 90% control for the first two sample periods. The other insecticides have varying levels of residue activity. These results indicate that none of the products evaluated will give effective control of adults once the insecticides have dried. However, Distance, Judo and Avid provided excellent immature whitefly control for 10 days while Distance and Judo provided an additional 6 days of excellent and good control, respectively. Sanmite managed to kill over 60% of the nymphs during the periods evaluated. This trial will be repeated and additional trials are planned to evaluate the residual activity of other insecticides used to manage whiteflies. These results will enable grower and extension personnel to better understand the residual activity of insecticides. This will in turn result in better insecticide rotation programs for the management of whiteflies.