Diana Roberts

Trap Response of Dargida terrapictalis (Buckett) (Lepidoptera: Noctuidae) to a Sex Attractant in Wheat-Growing Areas of Eastern Washington and Neighboring Oregon

Abstract Traps in eastern Washington and northeast Oregon wheat fields, baited with a sex attractant for the moth of the wheat head armyworm Dargida diffusa (Walker), captured the congener moth Dargida terrapictalis (Buckett). When the two components of a sex attractant for the wheat head armyworm were tested singly versus together in a trap, nearly all D. terrapictalis captured were in traps baited with the combination of (Z)-11-hexadecenyl acetate and (Z)-11-hexadecenal, indicating synergy of the two compounds as attractants. Traps baited with this sex attractant and maintained through the growing season captured D. terrapictalis primarily in May in Umatilla County, Oregon, and in June and early July in eastern Washington. Small numbers of D. diffusa were present also in these traps, largely coincident in time with D. terrapictalis captured. This is the first demonstration of a sex attractant for D. terrapictalis and confirms the presence of D. diffusa in the states of Oregon and Washington through the identification of trapped moths.

A Sex Attractant for Trapping Crambus cypridalis (Lepidoptera: Crambidae)

Crambus cypridalis (Hulst) (Lepidoptera: Crambidae) is widely distributed throughout the western United States (Crawford & Harwood 1964; Powell & Opler 2010). The larvae probably feed on grasses, as do congeneric species (Robinson et al. 2002), but it is not reported as a crop pest. Monitoring of wheat head armyworm moth Dargida (= Faronta) diffusa (Walker) and the sibling species Dargida (= Faronta) terrapictalis (Buckett) in eastern Washington resulted in ser endipitous captures of male C. cypridalis in sex attractant-baited traps (Landolt et al. in press). This result led us to test the hypothesis that C. cypridalis males are attracted to the combination of (Z)-ll-hexadecenyl acetate (Zll-16Ac) and (Z) 11-hexadecenal (Zll-16Ald). We also report new information on the seasonal timing of captures of C. cypridalis in sex-attractant traps, which was not included by Landolt et al. (2011). Chemicals were dispensed from red rubber septa (West Co., Lionville, Pennsylvania) and tested in UniTraps (Agrisense Inc., Pontyprid, United Kingdom) with a 6 cm2 piece of Vapor tape® (Hereon Environmental, Emigsville, Penn sylvania) placed within each trap bucket. Traps were attached to stakes at the edges of wheat fields.

Classical biological control of the cereal leaf beetle, Oulema melanopus (Coleoptera: Chrysomelidae), in Washington State and rôle of field insectaries, a review

ABSTRACT The cereal leaf beetle (CLB) Oulema melanopus (Coleoptera: Chrysomelidae), was considered a high risk to Washington State’s cereal grain production when the pest was found there in 1999. Biological control agents, which had proven successful in the Midwest, were introduced beginning in 2000. The parasitoids were released into field insectaries that were modified for the region and set up at CLB hotspots across the state. The egg parasitoid, Anaphes flavipes (Förster) (Hymenoptera: Mymaridae), failed to establish. The larval parasitoid, Tetrastichus julis (Walker) (Hymenoptera: Eulophidae), established successfully at all insectaries. Assays of commercial grain fields showed the parasitoid dispersing widely beyond the insectaries. A proactive Extension programme enabled farmers to benefit from the biocontrol without applying insecticides to manage the CLB. A modified insectary, consisting of oat strips seeded between commercial fields of winter and spring wheat, demonstrated potential as a way for farmers to increase parasitoid populations on their land. Within 5 years of first overwintering, T. julis had established across the state and was effectively suppressing CLB.

Seasonal response of Noctua pronuba Linnaeus, 1758 (Lepidoptera: Noctuidae) to traps in Washington State

Abstract. Noctua pronuba Linnaeus, 1758 (Lepidoptera: Noctuidae), the yellow underwing moth, was recently introduced into western North America. Blacklight traps at multiple sites in eastern Washington State indicate two broad periods of moth flight. A spring flight was evident in May and June, and a late season flight was evident from late August into October. Noctua pronuba moths were captured also in traps baited with acetic acid plus 3-methyl-1-butanol, but not in traps baited with acetic acid or 3-methyl-1-butanol alone. This chemical combination is thought to be a feeding attractant for many noctuid moths and may be useful for monitoring N. pronuba. The seasonal pattern of moths captured in traps baited with this chemical lure was similar to the pattern seen with blacklight traps.