Integrating inundative releases of Trichogramma ostriniae with Spinosad in bell pepper to control European corn borer
Vonny M. Barlow, Vmbarlow@vt.edu1, Thomas P. Kuhar, firstname.lastname@example.org, Edwin E Lewis, email@example.com, Ruth V. Hazzard, firstname.lastname@example.org, Shelby J. Fleischer, email@example.com, and Michael P. Hoffmann, firstname.lastname@example.org. (1) Virginia Tech, Department of Entomology, Painter, VA, (2) University of Massachusetts, Department of Entomology, Amherst, MA, (3) The Pennsylvania State University, Department of Entomology, University Park, PA, (4) Cornell University, Department of Entomology, Ithaca, NY
In 2002-2003 we demonstrated that inundative releases of Trichogramma ostriniae (Peng & Chen) could successfully parasitize Ostrinia nubilalis Hübner egg masses in bell pepper. Parasitization for both years of the study was significantly higher (P=0.0001) in release plots compared to controls (48.7% and 1.9% respectively). The result was decreased fruit damaged by O. nubilalis from 27.3% to 8.7% (P=0.0031). Although parasitism was high, for adequate control of O. nubilalis, mortality rates from parasitism and other factors would need to be higher in pepper for acceptable levels of control to be achieved.
In 2003-2004 we assessed the efficacy of combining T. ostriniae and foliar applications of Spinosad for control of O. nubilalis in bell pepper. A split-plot field design (2 (Trichogramma) x 2 (Spinosad)) was used for 4 sites in Virginia. Each 0.02 ha plot consisted of ≈ 600 pepper plants that received 5 inundative releases of ≈ 100,000 T. ostriniae. At multiple harvests (timing determined using phenology models), we sampled destructively ≈ 200 mature fruit to assess O. nubilalis fruit damage. The use of foliar applied Spinosad + T. ostriniae resulted in > 40% parasitism of O. nubilalis egg masses by T. ostriniae and a concomitant >50% reduction in damaged fruit. These data suggest that foliar applications of Spinosad do not have a significant impact on T. ostriniae parasitization of O. nubilalis and that the two tactics may be integrated into a successful Integrated Pest Management (IPM) program in peppers.
Species 1: Hymenoptera Trichogrammatidae Trichogrammaostriniae Species 2: Lepidoptera Crambidae Ostrinianubilalis (European corn borer) Keywords: Biological control, Insecticide