Effect of spinosad and predatory mites on control of Frankliniella occidentalis in three strawberry cultivars

Abstract

Western flower thrips, Frankliniella occidentalis (Pergande) (Thysanoptera: Thripidae), is a major pest of strawberry, Fragaria · ananassa Duchesne (Rosaceae). Spinosad is highly efficacious against F. occidentalis, and spinosad is believed to be compatible in an integrated pest management program. This study determined whether F. occidentalis could be controlled with predatory mites [Typhlodromips montdorensis (Schicha), Neoseiulus cucumeris (Oudemans) (both Acari: Phytoseiidae), and Hypoaspis miles (Berlese) (Acari: Laelapidae)] and spinosad in strawberry. In the glasshouse, three strawberry cultivars (Camarosa, Camino Real, and Albion) were sprayed once with spinosad at the recommended rate (80 ml 100 l )1 rate, 0.096 g a.i. l )1 ) or with water (control). Thrips adults were released onto plants 24 h after spraying and predatory mites released 6 days later. Spinosad significantly reduced thrips numbers compared with water. All three mite species reduced F. occidentalis numbers, and spinosad had no effect on predatory mites. Though H. miles could not be counted, the numbers of thrips in treatments with H. miles were lower than those in treatments without the mite. Thrips numbers were lowest on Camino Real and highest on Camarosa. These results suggest that the use of Camino Real with spinosad applications followed by releases of predatory mites can significantly reduce thrips numbers.

Evaluation ofStratiolaelaos scimitusandNeoseiulus barkerifor biological control of thrips on greenhouse cucumbers

“…Stratiolaelaos scimitus Berlese (formerly known as Hypoaspis miles Womersley) (Acari: Laelapidae) is being produced commercially for control of glasshouse sciarids (Jess & Kilpatrick, 2000;Wright & Chambers, 1994) and F. occidentalis (Berndt, Meyhofer, & Poehling, 2004;Rahman, Broughton, & Spafford, 2011;Thoeming & Poehling, 2006). Although the potential value of S. scimitus has been tested abroad, this indigenous species in China has not yet been extensively studied and applied (Wang et al, 2009;Wang, Liu, et al, 2010).…”

Use of spinosad and predatory mites for the management of Frankliniella occidentalis in low tunnel‐grown strawberry

“…In the laboratory, the numbers of thrips adults and larvae, T. montdorensis and N. cucumeris in each flower and fruit were counted and averaged per flower or fruit. As a result of the difficulty of sampling of H. miles in our previous study (Rahman et al., 2011a), no attempt was made to count H. miles .…”

“…The third mite, H. miles , is a soil‐dweller that predates on the prepupal and pupal stages (Glockemann, 1992), although Berndt (2003) suggests that it may also prey on late second instars of F. occidentalis . In a previous study, we reported that these species effectively reduced F. occidentalis numbers in strawberry grown under controlled conditions (Rahman et al., 2011a). Moreover, multiple‐species releases of these predatory mites are more effective than single‐species releases (Rahman et al., 2011b).…”

Biological control of western flower thrips,Frankliniella occidentalis(Pergande) (Thysanoptera: Thripidae), in gerberas, chrysanthemums and roses

“…On strawberries, T. montdorensis has been shown to reduce thrips numbers significantly more than N. cucumeris (Rahman et al 2011a(Rahman et al ,b,c, 2012.…”

“…Comparisons between T. montdorensis and N. cucumeris found that both predatory mites reduced the numbers of thrips equally. On strawberries, T. montdorensis and N. cucumeris were also able to reduce thrips numbers similarly, although T. montdorensis was able to reduce WFT slightly more than N. cucumeris on occasion (Rahman et al 2011a(Rahman et al ,c, 2012. The biology of N. cucumeris and T. montdorensis is quite similar, but T. montdorensis has been shown to have a higher intrinsic rate of increase than N. cucumeris (Steiner et al 2003), and to consume more thrips larvae per day (Vanhouten et al 1995).…”