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Chaskopoulou A.,USDA ARS European Biological Control Laboratory | Chaskopoulou A.,University of Florida | Latham M.D.,Manatee County Mosquito Control District | Pereira R.M.,University of Florida | And 3 more authors.
Journal of the American Mosquito Control Association | Year: 2011

We assessed the efficacy of ultra-low volume aerial adulticiding with 2 new water-based, unsynergized formulations of Aqua-K-Othrin (2% deltamethrin) and Pesguard S102 (10% d-phenothrin) against the riceland mosquitoes of Greece. A helicopter with Global Positioning System (GPS) navigation, real-time weather recording, and spray dispersal modeling (AgDISP) was utilized to accurately treat the experimental blocks by adjusting spray line positions to changing meteorological conditions. Two application rates were applied per formulation that corresponded to 0.75 and 1.00 g AI/ha of deltamethrin and 7.50 and 10.00 g AI/ha of d-phenothrin. The mosquitoes used for the trials were the main nuisance species found in rice field areas of Thessaloniki, which were primarily Aedes caspius, followed by Culex modestus and Anopheles sacharovi. Overall mean mortality of caged mosquitoes was 69.2% and 64.8% for deltamethrin and d-phenothrin, respectively. Mean population decrease in wild mosquito populations within the treatment areas was 76.5% and 78% for deltamethrin and d-phenothrin, respectively. The AgDISP dispersal model, coupled with GPS navigation and real-time weather recording, enabled accurate placement of the spray cloud such that the majority of the treatment area received sufficiently high droplet densities to result in uniform caged-mosquito mortality across all sampling sites. © 2011 by The American Mosquito Control Association, Inc. Source

Rodriguez-Saona C.,Rutgers University | Kaplan I.,Purdue University | Braasch J.,Purdue University | Chinnasamy D.,Tamil Nadu Agricultural University | Williams L.,USDA ARS European Biological Control Laboratory
Biological Control | Year: 2011

Methyl salicylate (MeSA) is a herbivore-induced plant volatile that has shown potential in attracting natural enemies. Here, we conducted a meta-analysis to evaluate the magnitude of natural enemy response to MeSA in the field, and tested its attractiveness to insect predators in commercial cranberry bogs. Eighteen experiments from 14 publications were used in the meta-analysis, resulting in 91 total observations. Of these, 41 documented significant attraction and the magnitude of this attraction response was not significantly different across predator and parasitoid taxa. Insect predators were monitored in cranberries using MeSA (PredaLure)-baited and unbaited yellow sticky traps. MeSA-baited traps caught greater numbers of adult hoverfly, Toxomerus marginatus, lady beetles, and green lacewings compared with unbaited traps. In another field experiment, predator abundance was monitored using traps placed near the MeSA lure (0 m), as well as at 2.5, 5, and 10 m away from the lure. Adult T. marginatus, the dominant predator species, showed a clear attraction to the point source but not to the other distances. In complementary studies we showed that MeSA emissions from PredaLures dropped quickly soon after deployment in the field but remained relatively high for over 4 weeks; flowering, but not vegetative, vines were a primary source of MeSA in cranberries; and, exposure to PredaLures triggered elevated MeSA emissions from vegetative vines. In conclusion, we find strong evidence that insect predators are broadly attracted to MeSA in agricultural fields, including cranberries; yet, whether this behavior can be manipulated to improve biological control needs further investigation. © 2011 Elsevier Inc. Source

Williams L.,USDA ARS European Biological Control Laboratory | Hagler J.R.,U.S. Department of Agriculture | Tonkel K.C.,Great Basin
Entomologia Experimentalis et Applicata | Year: 2011

Marking biological control agents facilitates studies of dispersal and predation. This study examines the feasibility of marking the various life stages of a weed biological control agent, Diorhabda carinulata (Desbrochers) (Coleoptera: Chrysomelidae), by submersion in rabbit or chicken immunoglobulin G (IgG) protein solutions. We determined whether externally applied IgGs are effective labels of the various lifestages, whether IgGs can be retained between D. carinulata lifestages, and to what extent abiotic factors associated with field conditions mediate label retention. The presence of the labels on the various lifestages of the beetles was detected by IgG-specific enzyme-linked immunosorbent assays. Duration of each immunolabel was measured on eggs and larvae in laboratory studies and on adults in laboratory and field studies. For adults, both labels showed high (>80%) retention for ca. 14days after marking under field and laboratory conditions. Temperature and type of label (rabbit or chicken) had only a minimal effect on marker retention. Externally marked eggs exhibited high (100%) retention for both proteins over the entire duration of the egg stage. Interestingly, some larvae emerging from externally labeled eggs contained both external and internal IgG marks. To our knowledge, this is the first case of an IgG being transferred from the egg to larva of an insect. Age of eggs at the time of label application affected the intensity of the external label on neonates. For instance, larvae that emerged from eggs that were >1day old when labeled exhibited stronger label retention than larvae that emerged from eggs that were 1day old when labeled. For larvae, retention of rabbit IgG was greater than retention of chicken IgG. Label retention declined as larvae aged; larvae >3days old retained significantly less label than did neonate larvae. Both IgG labels were retained from the first to second instar, but at a very low rate of <10%. Overall, our study demonstrates that protein-marking technology has potential for use in studies of dispersal and predator-prey associations for D. carinulata. © 2011 The Netherlands Entomological Society. Source

Saadat D.,Shahid Chamran University | Seraj A.A.,Shahid Chamran University | Goldansaz S.H.,University of Tehran | Williams L.,USDA ARS European Biological Control Laboratory
Biological Control | Year: 2016

Augmentative releases of native natural enemies are viable strategies for suppression of crop pests. Successful implementation of this approach requires in-depth knowledge of the natural enemy, its host(s), and the agroecosystem. In particular, appropriate mass rearing and release strategies rely on a thorough understanding of the reproductive biology of the natural enemy. In the present study, we evaluated the effects of parasitoid source (host habitat origin), fruit condition (i.e., ease of host access for parasitoid), impact of using an alternative host for rearing, and winter-simulated cold storage of hosts on the reproductive performance of Bracon hebetor. Several life history parameters, including attack behavior, proportion of paralyzed hosts, parasitism, oviposition, offspring sex ratio, and life table parameters were measured. Wasps originating from a pomegranate orchard-Ectomyelois ceratoniae host habitat generally had greater reproductive performance than those sourced from stored dry fruit-Plodia interpunctella or tomato field-Helicoverpa armigera habitats. Hosts infesting intact pomegranate fruit suffered greater levels of attack (e.g., paralysis, parasitism, and oviposition) than did more accessible hosts infesting damaged fruit. However, offspring sex ratio was generally more female-biased in the damaged fruit treatments. The developmental period of B. hebetor larvae and pupae was shorter (mean generation time) on Ephestia kuehniella hosts that had been subjected to a 2-month cold storage period (winter simulation) than untreated control hosts not subjected to cold storage. Sex ratio of offspring did not differ significantly between the treatments. Our studies demonstrated differential effects of wasp population source, and other biotic factors, on the reproductive biology of B. hebetor. Our current understanding suggests that efficacious protection of pomegranate crops with B. hebetor might be accomplished by using a rearing protocol that incorporates parasitoids originating from a pomegranate-E. ceratoniae source, followed by rearing on cold-treated E. kuehniella prior to release. Development of optimal release strategies is a topic for future studies. © 2016. Source

Maguire D.Y.,McGill University | Maguire D.Y.,USDA ARS European Biological Control Laboratory | Buddle C.M.,McGill University | Bennett E.M.,McGill University
PLoS ONE | Year: 2016

Fragmentation changes the spatial patterns of landscapes in ways that can alter the flow of materials and species; however, our understanding of the consequences of this fragmentation and flow alteration for ecosystem processes and ecosystem services remains limited. As an ecological process that affects many ecosystem services and is sensitive to fragmentation, insect herbivory is a good model system for exploring the role of fragmentation, and the resulting spatial patterns of landscapes, in the provision of ecosystem services. To refine our knowledge of how changes in landscape pattern affect insect herbivory, we quantified the combined influence of among patch (patch area and patch connectivity) and within patch (location within patch; canopy, edge, interior) factors on amounts of insect herbivory in a fragmented forest landscape. We measured herbivory in 20 forest patches of differing size and connectivity in southern Quebec (Canada). Within each patch, herbivory was quantified at the interior, edge, and canopy of sugar maple trees during the spring and summer of 2011 and 2012. Results show that connectivity affects herbivory differently depending on the location within the patch (edge, interior, canopy), an effect that would have gone unnoticed if samples were pooled across locations. These results suggest considering structure at both the patch and within patch scales may help to elucidate patterns when studying the effects of fragmentation on ecosystem processes, with implications for the services they support. © 2016 Maguire et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited. Source

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