Within-Plant Distribution of <I>Frankliniella</I> species (Thysanoptera: Thripidae) and <I>Orius insidiosus</I> (Heteroptera: Anthocoridae) in Field Pepper

Management Strategies for Western Flower Thrips and the Role of Insecticides

“…This ongoing dispersal means that even repeated insecticide applications have little utility in reducing pest damage, especially in high value crops with low damage thresholds (Bauske, 1998;Kontsedalov et al, 1998). Once having landed on plants, western flower thrips preferentially reside within flowers or other concealed, protected places on plants (Hansen et al, 2003;Kirk, 1997a). This thigmotactic behavior of thrips limits their exposure to many foliar applied insecticides.…”

“…However, soon after the invasion of the western flower thrips, epidemics of tomato spotted wilt began to occur throughout the southeast (Csinos et al, 2009) and crops remain at risk if proper management is not employed . It is important to note that the most prevalent Frankliniella species in Florida and the southeastern USA are F. tritici (Fitch) and F. bispinosa (Morgan) (in southern Florida, Hansen et al, 2003), but these species do not cause the damage that western flower thrips do in vegetable crops. The extensive crop losses caused by western flower thrips and Tomato spotted wilt virus have spurred considerable research to develop effective management programs.…”

“…Similar results have been observed in crop fields where two-thirds or more of thrips in untreated or spinosad-treated pepper are the native species. Yet, the demographics differ in pyrethroid treated plots, where western flower thrips predominant (Hansen et al, 2003;Reitz et al, 2003). Because the native species F. tritici and F. bispinosa do not cause the economic damage that western flower thrips do, and because they outcompete western flower thrips, their conservation contributes to overall pest management.…”

“…We have found repeatedly that avoiding treatments that induce outbreaks of western flower thrips populations by killing natural enemies and competing species of native thrips within crop fields is an effective approach to minimizing losses to western flower thrips. Most broadspectrum synthetic insecticides, including pyrethroids, organophosphates, and carbamates kill the native species of thrips that outcompete western flower thrips (Hansen et al, 2003;Reitz et al, 2003;Srivistava et al, 2008), leading to dramatic large scale shifts in thrips demographics (Frantz & Mellinger, 2009). These synthetic broad-spectrum insecticides not only can disrupt western flower thrips management, they also can disrupt management of other pests including spider mites, whiteflies, and leafminers, by eliminating natural enemies of those pests.…”

Sampling Techniques for Thrips (Thysanoptera: Thripidae) in Preflowering Tomato

“…F. occidentalis has replaced Thrips tabaci as the dominant species in European greenhouses (van Rijn et al 1995) and has also been implicated in the displacement of F. intonsa in Turkey (Atakan and Uygur 2005) and the displacement of Frankliniella gemina (Bagnall) in Argentina (de Borbon et al 2006). However, F. occidentalis has failed to replace of Frankliniella tritici (Fitch) as the dominant species in the eastern United States (Salguero Navas et al 1991a, Reitz 2002, Paini et al 2007, Northfield et al 2008) and in central and southern Florida where Frankliniella bispinosa (Morgan) dominates (Childers et al 1990, Hansen et al 2003, Frantz and Mellinger 2009.…”