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ABSTRACT The soybean aphid, Aphis glycines Matsumura (Hemiptera: Aphididae), is native to eastern Asia and was accidentally introduced into North America in 2000. Within a few years, it was found throughout the U.S. and Canadian soybean-growing regions. The spread of .. glycines in North America is partly ascribed to its great flight capacity. We conducted direct measurements of flight performance of winged A. glycines adults and correlated this to their subsequent longevity and fecundity to determine whether there are trade-offs between flight and fecundity. We also estimated fecundity and development time of the offspring of females that had flown varying distances to examine potential maternal effects linked to flight. The experiment was conducted using a specifically designed aphid flight mill system in which winged aphids were tethered by their abdomens and flight duration, distance and speed were quantified. Fecundity, longevity and reproductive periods of 12-h-old A. glycines alates that had engaged in >0,5 km long flights were significantly lower than those of <0.5-km individuals. The offspring of alates with flight experiences of >1.5 km also had lower fecundity than those produced by individuals that had engaged in flights <1.5 km. Our results are therefore consistent both with direct trade-offs between flight and fecundity and a trade-off between flight and fecundity via maternal effects. [ABSTRACT FROM AUTHOR]

The parasitoid Binodoxys communis (Gahan) (Hymenoptera: Braconidae) is a candidate for release against the Asian soybean aphid, Aphis glycines Matsumura (Homoptera: Aphididae), in North America. Using a series of Y-tube olfactometer assays, we recorded responses of naïve and experienced B. communis females to odors from both target and non-target host plant complexes. The non-target host plant complexes included three aphid species native to North America [ Aphis monardae Oestlund, Aphis oestlundi Gillette, and Aphis asclepiadis (Fitch)] and one species presumed to be exotic to North America ( Aphis nerii Boyer de Fonscolombe), all on their respective host plants. We also investigated whether the parasitoid distinguishes between volatiles from soybean infested with A. glycines vs. those of uninfested plants. Volatiles from A. glycines-infested soybean plants and several non-target host plant complexes elicited a response in B. communis, which seemed to be reinforced through oviposition experience. Wasps with experience on a specific host plant complex increased their response to odors of this complex. Neither naïve nor experienced wasps, however, preferred odors from target vs. non-target host plant complexes in choice tests. Our data also indicate that B. communis is unable to distinguish between volatiles from infested vs. uninfested soybean plants. This study shows that B. communis females respond to a broad array of olfactory stimuli, exhibit low fidelity for any particular odor, and employ some behavioral plasticity in their response to volatile cues. We discuss implications of these results for establishment of B. communis and potential undesirable non-target effects associated with the release of this species in North America. [ABSTRACT FROM AUTHOR]

We present a synthetic review and expert consultation that assesses the actual risks posed by arthropod pests in four major crops, identifies targets for integrated pest management (IPM) in terms of cultivated land needing pest control and gauges the implementation "readiness" of non-chemical alternatives. Our assessment focuses on the world's primary target pests for neonicotinoid-based management: western corn rootworm (WCR, Diabrotica virgifera virgifera) in maize; wireworms (Agriotes spp.) in maize and winter wheat; bird cherry-oat aphid (Rhopalosiphum padi) in winter wheat; brown planthopper (BPH, Nilaparvata lugens) in rice; cotton aphid (Aphis gossypii) and silver-leaf whitefly (SLW, Bemisia tabaci) in cotton. First, we queried scientific literature databases and consulted experts from different countries in Europe, North America, and Asia about available IPM tools for each crop-pest system. Next, using an online survey, we quantitatively assessed the economic relevance of target pests by compiling country-level records of crop damage, yield impacts, extent of insecticide usage, and "readiness" status of various pest management alternatives (i.e., research, plot-scale validation, grower-uptake). Biological control received considerable scientific attention, while agronomic strategies (e.g., crop rotation), insurance schemes, decision support systems (DSS), and innovative pesticide application modes were listed as key alternatives. Our study identifies opportunities to advance applied research, IPM technology validation, and grower education to halt or drastically reduce our over-reliance on systemic insecticides globally.