There is a great demand for safe and effective alternative fumigants to replace methyl bromide and other toxic fumigants for postharvest pest control. Nitric oxide, a common signal molecule in biological systems, was found to be effective and safe to control insects under ultralow oxygen conditions. Four insect species including western flower thrips, Frankliniella occidentalis (Pergande) (Thysanoptera: Thripidae); aphid, Nasonovia ribisnigri (Mosley) (Homoptera: Aphididae); confused flour beetle, Tribolium confusimi Jacquelin du Val (Coleoptera: Tenebrionidae); and rice weevil, Sitophilus oryzae (L.) (Coleoptera: Curculionidae), at various life stages were fumigated with 0.1–2.0% nitric oxide under ultralow oxygen levels of ≤50 ppm in 1.9-liter glass jars at 2–25°C depending on insect species. Fumigations were effective against all four insect species. Efficacy of nitric oxide fumigation increased with nitric oxide concentration, treatment time, and temperature. There were also considerable variations among insect species as well as life stages in susceptibility to nitric oxide fumigation. Complete control of thrips was achieved in 2 and 8 h with 2.0 and 0.2% nitric oxide, respectively, at 2°C At the same temperature, complete control of the aphid was achieved in 3, 9, and 12 h with 1.0, 0.5, and 0.2% nitric oxide, respectively. Larvae, pupae, and adults of confused flour beetle were effectively controlled in 24 h with 0.5% nitric oxide at 20°C. Complete mortality of confused flour beetle eggs was achieved in 24 h with 2.0% nitric oxide at 10°C Rice weevil adults and eggs were effectively controlled with 1.0% nitric oxide in 24 and 48 h, respectively, at 25°C These results indicate that nitric oxide has potential as a fumigant for postharvest pest control.

Recently, specimens of a Periplaneta sp. were discovered in New York, NY, that did not match the typical morphology of Periplaneta americana L., the ubiquitous American cockroach. Here, we used DNA barcoding and morphological identification to confiIrm that this newly invasive pest species was indeed Periplaneta japonica Karny, 1908. We discuss this recent invasion in light of known life history traits of this species, with speciFIc predictions for its impact in the urban northeastern United States.

Hygienic behavior in honey bees is a heritable trait of individual workers that confers colony-level resistance against various brood diseases. Hygienic workers detect and remove dead or diseased brood from sealed cells. However, this behavior is quite rare, with only c.10% of unselected colonies showing high levels of hygiene. Beekeepers can potentially increase this by screening colonies for hygiene and breeding from the best. However, the level of hygiene expressed by a colony is variable, which poses a challenge to colony selection. In this study,wesystematically varied two factors thought to be of importance in influencing hygiene levels, “nectar” availability, by feeding or not feeding sucrose syrup, and brood amount, by adding or removing brood, to determine what effect they had on hygienic behavior.Wetested 19 colonies repeatedly over a 4-mo period using the freeze-killed brood assay, a standard technique to quantify hygienic behavior. Two days after freeze-killed brood treatment, our colonies showed a wide range of brood removal levels, with colony means ranging from 31.7 ± 22.5 to 93 ± 6.9 (mean% ± SD). Neither the food nor the brood manipulation had an effect on hygiene levels. Colony size and time of year were also nonsigniflcant. The only signiflcant effect was a three-way interaction between syrup availability, amount of brood, and time of the year, resulting in reduced hygienic behavior early in the season (spring), in colonies with added brood that were not fed sucrose syrup. Overall, these results suggest that hygienic behavior is not greatly affected by environmental conditions typical of a real-life beekeeping, and that screening of colonies can be done anytime without special regard to nectar conditions or brood levels.

Xyleborus glabratus Eichhoff (Coleoptera: Curculionidae: Scolytinae) is an invasive ambrosia beetle that vectors laurel wilt, a new disease that threatens avocado and other species in the Lauraceae Family. The lethal concentrations (LC_{50 & 90}) of nine commercial insecticides to X. glabratus were determined by using a bolt-dip bioassay. Different formulations of bifenthrin, permethrin, fenpropathrin, z-cypermethrin bifenthrin, l-cyhalothrin thiamethoxam, malathion, chlorpyrifos, carbaryl, and methomyl were tested. Four concentrations of each insecticide were tested (0.5, 0.1, 0.03, and 0.01 of the label rate) and with water as a control. Beetles were exposed to treated bolts and mortality registered 48 h later. After 2 wk, bolts were destructively sampled to determine the number of beetles that constructed galleries and were alive inside the wood. Probit analysis was used to determine the LC_{50 & 90}. Six pesticides were applied directly to the trunk and limbs of avocado trees in a commercial grove. Limbs of treated trees were cut weekly after the application and exposed to X. glabratus to determine the number of beetles boring into the logs. The toxicity of pesticides to X. glabratus was greatly reduced 2 wk after application. Among the tested pesticides, malathion and z-cypermethrin bifenthrin provided the best suppression of X. glabratus. Among the insecticides registered for use in avocado, fenpropathrin and malathion were the most effective in protecting trees from attack by X. glabratus. Other pesticides that are currently not registered for use in avocados could be useful for managing this ambrosia beetle.

Sex-dispersal differences of four phloem-feeding vectors and their relationship to wild-plant abundance were analyzed over 2 yr in two vineyard agroecosystems. Adults of Euscelis lineolatus Brullè, Neoaliturus fenestratus (Herrich-Schäffer), Psammotettix alienus (Dahlbom), and Hyalesthes obsoletus Signoret were sampled by using yellow sticky traps at two heights (20 and 150 cm) above the ground in a regular geo-referenced grid. Wild vegetation was surveyed around each sampling point. The most abundant species collected was N. fenestratus, followed by P. alienus, H. obsoletus, and E. lineolatus. Low traps were more effective in capturing the females of N. fenestratus and P. alienus and the males of all of the species, except N. fenestratus at one site. Sex ratio was male-biased for N. fenestratus in both agroecosystems at both trap heights, and only in low traps for H. obsoletus and P. alienus at one site. Insect abundance, temporal population dynamics, and dispersal patterns showed considerable fluctuations according to vineyard agroecosystems and years. In the current study, all of the four phloem-feeding vectors were not found homogeneously in the vineyards, and they were aggregated in correspondence with their herbaceous wild-plant hosts. Insects tended to disperse from the borders toward the vineyard, or vice versa. Colonizing pattern was strongly affected by border vegetation, fallow fields, and vineyard ground-cover vegetation. Different plant communities were identified inside the agroecosystems, and significant correlations among insect and plant-species abundances were recorded. Data highlight the importance of understanding the dispersal patterns of vector species for the application of correct integrated pest-management strategies.

The South American tomato leafminer, Tuta absoluta Meyrick (Lepidoptera: Gelechiidae), is a major pest that has recently invaded Afro-Eurasia. Biological control, especially by Trichogramma parasitoids, is considered to be promising as a management tool for this pest. However, further development of Trichogramma-based biocontrol strategies would benefit from assessing the impact of released parasitoid offspring on the pest. Under laboratory conditions, we 1) compared the parasitism of five Trichogramma species-strains on the pest-plant system T. absoluta-tomato, and 2) assessed various biological traits of parasitoids, mass-reared on a factitious host (Ephestia kuehniella Zeller), when developing on T. absoluta. In addition, we evaluated the overall efficiency of two specific Trichogramma species when released under greenhouse conditions in combination with a common natural enemy in tomato crop, the predator Macrolophus pygmaeus Rambur. Parasitoids emerging from T. absoluta on tomato showed lower parasitism rates and poor biological traits, for example, wing deformations, reduced longevity, when compared with the control reared on the factitious host. Under greenhouse conditions, the parasitoids that developed on T. absoluta after initial releases contributed little to biological control of T. absoluta, and parasitism tended to be lower when the predator was present. However, a slightly higher T. absoluta control level was achieved by combining the predator and release of the parasitoid Trichogramma achaeae Nagaraja and Nagarkatti. This study shows that Trichogramma parasitoids may not build up populations on the T. absoluta-tomato system, but that Trichogramma parasitoids can be used in combination with M. pygmaeus to enhance biological control of the pest in tomato crops.

Bioassays were designed to evaluate Beauveria bassiana (Balsamo) Vuillemin strain GHA against Listronotus maculicollis (Kirby) adults. B. bassiana and its “inert” carrier oil in the product BotaniGard and the inert carrier oil alone provided 99 and 96% mortality, respectively, in petri dish assays 1 d after treatment when applied in 1 ml water. When the same treatments were applied in 0.5 ml of carrier water, mortality was only 1.4 and 0.7%, respectively, 1 d after treatment. After 10 d in petri dishes, B. bassiana and its inert carrier oil and the inert carrier oil alone applied in 0.5 ml water showed 77 and 9% mortality, respectively. When one-tenth the label dosage of B. bassiana and inert carrier oil was combined with neonicotinoids applied in 1 ml water, there were significant increases in weevil mortality over the neonicotinoids alone 1 d after treatment. When 88.7% of one-tenth the label dosage of inert carrier oil alone was combined with neonicotinoids clothianidin, imidacloprid, and dinotefuran applied in 1 ml water, there was also a significant increases (38%) with clothianidin in weevil mortality over clothianidin alone 1 d after treatment. B. bassiana and its inert carrier oil provided 28, 50, and 78% mortality at the highest label dosage and 47, 76, and 89% mortality at 4× the highest label dosage in turf plug assays at 7, 10, and 14 d after treatment. Addition of 5 or 20% MycoMax (a nutrient source for B. bassiana) did not significantly increase mortality.

Noncrop plant communities present on the boundaries or within crop fields are essential for the maintenance of functional biodiversity, affecting beneficial insect numbers and ecological fitness. Habitat manipulation is an increasingly studied strategy aimed at enhancing natural enemies of agricultural pests by providing feeding and shelter resources. In this study, six plant species selected from preliminary work were tested for their potential attractiveness to four common aphidophagous hoverflies species. Potential attractiveness was evaluated through observation of hoverfly feeding visits to replicated flower plots distributed in a randomized design. The combination of the selected species covered a 2-mo full-bloom period. Sphaerophoria scripta L. and Sphaerophoria rueppellii (Wiedeman) were the dominant hoverflies present throughout the sampling period, whereas Eupeodes corollae (F.) and Episyrphus balteatus (DeGeer) visits were less abundant and appeared only in the early season. Potential attractiveness varied among plant species. Calendula arvensis L. and Coriandrum sativum L. were the most visited species. C. arvensis received a high number of visits throughout a long period, whereas the visits to Co. sativum were concentrated in a short blooming period. These results suggest that habitat management by using these plant speciesmay increase the abundance of hoverflies and could improve the biological control of aphid pests typical of spring-summer crops in open Mediterranean environments.

The peach fruit fly, Bactrocera zonata (Saunders), attacks a wide range of tree fruits in countries from Egypt to Vietnam and is occasionally trapped in the United States. Phytosanitary treatments may be required to export fruit hosts of this insect from countries where it is endemic to countries where it is absent but could become established. This research describes comparative studies to determine if B. zonata could be phytosanitarily controlled by cold treatment schedules existing for Ceratitis capitata (Wiedemann) and Anastrepha ludens (Loew), and the development of a cold treatment of 18 d at 1.7°C for B. zonata infesting oranges. Fruit were infested by puncturing holes in oranges and allowing tephritids to oviposit in the holes. The treatments were initiated when the larvae reached late third instar because previous research had shown that stage to be the most cold-tolerant. B. zonata was not found to be confidently as or less cold tolerant than C. capitata; therefore, treatment schedules for the latter are not supported by this research for the former. B. zonata was found to be more susceptible to 1.7°C than A. ludens; therefore, the use of treatment schedules for A. ludens is supported by this research for B. zonata. However, the treatment for A. ludens requires 22 d. A shorter treatment was verified for B. zonata when 36,820 third instars reared from the eggs in oranges were stored at 1.7°C for 18 d with no larvae moving on examination 24 h after removal from the cold treatment chamber.

The postharvest control of arthropod pests is a challenge that the California citrus industry must overcome when exporting fruit overseas. Currently, methyl bromide fumigation is used to control postharvest pests on exported citrus, but it may soon be unavailable because of use restrictions and cost of this health-hazard ozone-depleting chemical. Ethyl formate is a natural plant volatile and possible alternative to methyl bromide in postharvest insect control. The objectives of this study were 1) to evaluate the mortality of third instar California red scale [Aonidiella aurantii (Maskell)] (Hemiptera: Diaspididae) and adult western flower thrips [Frankliniella occidentalis (Pergande)] (Thysanoptera: Thripidae) under a wide range of ethyl formate concentrations, 2) to determine the ethyl formate concentration required to reach a Probit 9 level of control for both pests, and 3) to test the effects of ethyl formate fumigation on the quality of navel oranges [Citrus sinensis (L.) Osbeck] and lemons [Citrus limon (L.) Burman f.] at 24 h after fumigation, and at different time periods to simulate shipping plus storage (5 wk at 5°C), and shipping, storage, handling, and shelf-life (5 wk at 5°C, plus 5 d at 15°C, and 2 d at 20°C). The results indicate that ethyl formate is a promising alternative to methyl bromide for the California citrus industry, because of successful control of adult western flower thips and third instar California red scale and no deleterious effect on fruit quality at any of the evaluated periods and quality parameters.

To determine the risk winery waste poses for the spread of Lobesia botrana (Denis & Schiffermüller) (Lepidoptera: Tortricidae) in California, we evaluated the survival of larvae in artificially infested grape clusters (Vitis vinifera L.) processed for wine making. The trial consisted of five treatments: whole cluster pressing to 1 bar (100,000 Pa); whole cluster pressing to 2 bars (200,000 Pa); destemming and berry pressing to 1 bar; destemming and berry pressing to 2 bars; and control. Each treatment was replicated with the following five winegrape varieties: Chardonnay, Sauvignon Blanc, Gewürztraminer, Yellow Muscat, and Cabernet Sauvignon. All winery waste was inspected for larval survival. No live larvae were recovered from any of the treatments in all five varieties; therefore, the hypothesis that green winery waste contributes to the spread of L. botrana was rejected.

Behavioral bioassays were used to isolate compounds from germinating corn roots that elicit a host recognition response (tight-turning behavior) by neonate larvae of the western corn rootworm Diabrotica virgifera virgifera LeConte. When a behaviorally active extract of germinating corn roots was separated into an aqueous partition and a hexane partition, significantly more larvae (P < 0.05) responded to the recombined partitions than to either partition alone, demonstrating that the active material is a blend comprising both polar and nonpolar compounds. When the aqueous partition was separated with reverse-phase solid phase extraction, most of the behavioral activity was retained in the 100% water fraction (F-1). Gas chromatography-mass spectrometry analysis determined that F-1 contained a blend of small sugars, diacids, amino acids, and inorganic compounds. The nonpolar partition was separated on a silica column, and the resulting fractions were tested in combination with F-1 from the aqueous separation. More than 70% of larvae responded to the 100% acetone fraction (fraction B) in combination with F-1, and the response to this treatment was significantly higher than responses to the other nonpolar fractions or to F-1 alone. Methyl esterification of fraction B, followed by gas chromatographic fatty acid methyl ester analysis, confirmed that fraction B primarily consisted of lipids containing fatty acyl groups.

The objective of this research was to evaluate artificial diets that can be used to successfully culture the atlas silk moth, Attacus atlas L. (Lepidoptera: Saturniidae) indoors. Four plant species were evaluated as the basic component of each diet, barringtonia (Barringtonia asiatica), cheesewood (Nauclea orientalis), soursop (Annona muricata), and mahogany (Swietenia mahagoni). Evaluation of the nutritional value of each diet was determined by an analysis of the hemolymph proteins of sixth instars using the Folin-Ciocalteu assay. Survivorship, cocoon quality, and hemolymph protein content of larvae fed the barringtonia diet were higher than those of larvae fed mahogany-, cheesewood-, and soursop-based artificial diets. The average adult emergence of those fed the barringtonia-based diet was 74.5%. The weights of the cocoon in this treatment with the pupa and the empty cocoons were 7.0 and 1.1 g, respectively. Hemolymph of the larvae fed the barringtonia-based artificial diet had the highest concentration of protein with an average of 28.06 mg/ml. The atlas moth reared on the barringtonia-based artificial diet was comparable with those reared only on barringtonia leaves. However, the weight of empty cocoons, adult wingspan, and amount of hemolymph protein were lower than in those reared on barringtonia leaves only. This may suggest that the artificial barringtonia-based diet requires additional protein for maximum efficiency.

Determination of negative nontarget effects of pesticides on beneficial organisms by measuring only lethal effects is likely to underestimate effects of sublethal doses. In this study, the sublethal effects of fenpropathrin on the predatory thrips Scolothrips longicornis Priesner (Thysanoptera: Thripidae) fed on Tetranychus urticae Koch (Acari: Tetranychidae) were evaluated under laboratory conditions. The estimated values of LC₅₀ for female and male predators were 6.53 and 5.47 µg a.i./ml, respectively. Exposure to low-lethal concentrations (LC₁₀, LC₂₀, and LC₃₀) of fenpropathrin significantly affected the biological characteristics of treated females of S. longicornis, the most noticeable effects being a shortening of female life span by >70% accompanied by large reductions in oviposition period and fecundity. The offspring of females treated with low-lethal concentrations of fenpropathrin likewise had significantly reduced longevity, oviposition period, and fecundity, although not to the same extent as experienced by their mothers. Their juvenile development time was, however, not affected. These effects on the offspring were reflected in reduced rates of population increase and increased doubling times.

A field experiment was conducted in Stoneville, MS, during 2010 and 2011 to investigate the impact of varietal maturity, planting date, and insecticide application on tarnished plant bug, Lygus lineolaris (Palisot de Beauvois), populations and damage in cotton. Four planting dates were selected to encompass the cotton-planting period in Mississippi. An early and late maturing variety were planted at each planting date, and each variety and planting date combination was either sprayed or unsprayed for tarnished plant bugs. Plots were sampled weekly from first square until physiological maturity. Plots were harvested at the end of the season. Early planting dates had lower densities of tarnished plant bug and required fewer insecticide applications than the later planting dates. Mid-April to early May planting dates sustained less yield loss from tarnished plant bug than mid-May to late-May planting dates. Tarnished plant bug had less impact on yield of the early maturing variety than on the late maturing variety. The sprayed plots yielded more than unsprayed plots. These data demonstrate that later plantings of cotton in the Mississippi Delta are likely to experience yield losses from tarnished plant bug and need to be sprayed more compared with early cotton plantings. As a result, growers should manage their crop for earliness through planting date and varietal selection.

Since its discovery in North America in 2000, the soybean aphid, Aphis glycines Mat-sumura (Hemiptera: Aphididae), has rapidly become an important pest of soybean [Glycine max (L.) Merrill], sometimes resulting in significant yield losses. Previous research has documented the toxicity of neonicotinoid seed treatments to soybean aphids, but control under field conditions has been inconsistent. Imidacloprid, a popular neonicotinoid insecticide, has been shown to exhibit antifeedant effects on aphids. Antifeedant activity has not been demonstrated for other neonicotinoids, including thiamethoxam. This research investigated the effects of a thiamethoxam seed treatment on soybean aphid feeding behavior by using electronic penetration graphs (EPG) to visualize stylet penetration behavior. Soybean aphid feeding behavior was assessed for 9 h on thiamethoxam-treated and untreated soybeans (V2 and V4 stages). Because results were inconclusive from initial experiments, a study was conducted to document the effects of thiamethoxam-treated soybeans on soybean aphid survival. The seed treatment was shown to negatively affect aphid survival at 4, 8, and 11 d after aphid introduction. A subsequent EPG study then was designed to document soybean aphid feeding behavior for 15 h, after an initial exposure of 9 h to thiamethoxam-treated soybeans. In this study, the exposed aphids exhibited significant differences in feeding behavior compared with those aphids feeding on untreated soybeans. Soybean aphids on thiamethoxam-treated soybeans spent significantly less time feeding in the sieve element phase, with a greater duration of nonprobing events. These studies suggest soybean aphids are unable to ingest phloem sap, which may be another important element in seed treatment protection.

We provide the first report of Matsucoccus macrocicatrices Richards (Hemiptera: Mat-sucoccidae) feeding and reproducing on eastern white pine, Pinus strobus L., in the southeastern United States. Until now, M. macrocicatrices had been reported only from the Canadian Atlantic Maritimes, New Hampshire, and Massachusetts. Entomological holdings of 27 major museums in eastern North America have no historical records for M. macrocicatrices from the southeastern region. However, our field surveys and molecular analyses (DNA barcoding) have resulted in the collection and positive identification of M. macrocicatrices in Georgia, North Carolina, South Carolina, Tennessee, Virginia, and West Virginia. In addition to the new geographic range, M. macrocicatrices is also being associated with dieback and mortality of all diameter classes of P. strobus leading to concern about a potential shift from its historically nonpestiferous presence on the host tree. On P. strobus, M. macrocicatrices was found embedded in cankers or present on top of the bark with necrotic tissue under their feeding area, indicating that they may be creating wounds for opportunistic pathogenic fungi to infest. Further, we found M. macrocicatrices living outside of the epiphytic mats of its symbiotic fungus, Septobasidium pinicola Snell. This study shows that M. macrocicatrices is now widespread in the southeastern United States, with implications for the future survival and regeneration of P. strobus in eastern North America.

Widespread mortality of eastern hemlock, Tsuga canadensis (L.) Carrière, resulting from infestation by hemlock woolly adelgid, Adelges tsugae Annand (Hemiptera: Adelgidae), has occurred throughout the native range of eastern hemlock within the eastern United States. Imida-cloprid, a systemic insecticide, is one of the primary chemical compounds used to control hemlock woolly adelgid in both urban and, in a limited manner, in natural forest environments. The metabolism of imidacloprid in eastern hemlock produces 12 metabolites; two of these, imidacloprid 5-hydroxy and imidacloprid olefin, are considered toxicologically important metabolites. However, little is known about the persistence of these metabolites in eastern hemlock in the southern Appalachians. Concentrations of imidacloprid, olefin, and 5-hydroxy were quantified by using HPLC/MS/MS techniques. Over the 3-yr study, concentrations of imidacloprid and consequent 5-hydroxy and olefin were highest in trees treated with a soil injection in the spring. Imidacloprid and 5-hydroxy concentrations in sap were highest at 12 mo posttreatment and in tissue at 15 mo posttreatment. Imidacloprid was detected through 36 mo posttreatment and 5-hydroxy was detected through 15 mo posttreatment. Olefin concentrations in both sap and tissue were highest at 36 mo posttreatment and were detected in high concentrations through 36 mo posttreatment. Concentrations of imidacloprid were highest in the bottom stratum of the canopy and lowest in the top stratum. Concentrations of olefin and 5-hydroxy were highest in the top stratum and lowest in the bottom stratum.

The current emerald ash borer survey trap used in the United States is a prism trap constructed from a stock purple corrugated plastic. In recent years, several colors (particularly shades of green and purple) have been shown to be more attractive to the emerald ash borer than this stock color. Our goal was to determine if plastics produced with these colors and incorporated into prism traps can improve and serve as a new alternative to plastics already in use for the emerald ash borer survey. The plastics were tested in moderate to heavily infested areas in Michigan in two initial studies to test their effectiveness at catching the emerald ash borer. Because results from studies performed in heavily infested sites may not always correspond with what is found along the edges of the infestation, we compared trap catch and detection rates (recording at least one catch on a trap over the course of the entire trapping season) of several trap types and colors at sites outside the core of the currently known emerald ash borer infestation in a nine-state detection tool comparison study. Two of the new plastics, a (Sabic) purple and a medium-dark (Sabic) green were incorporated into prism traps and tested alongside a standard purple prism trap and a green multifunnel trap. In areas with lower emerald ash borer density, the new purple (Sabic) corrugated plastic caught more beetles than the current purple prism trap, as well as more than the medium-dark green (Sabic) prism and green multifunnel traps. Sabic purple traps in the detection tools comparison study recorded a detection rate of 86% compared with 73, 66, and 58% for the standard purple, Sabic green, and green multifunnel traps, respectively. These detection rates were reduced to 80, 63, 55, and 46%, respectively, at low emerald ash borer density sites.

Field assays were conducted in southeastern and south-central Michigan in 2011 and 2012 to optimize green and purple multifunnel (Lindgren funnel) traps for use as a survey tool for the emerald ash borer, Agrilus planipennis Fairmaire. Larger sized (12- and 16-unit) multifunnel traps caught more beetles than their smaller-sized (4- and 8-unit) counterparts. Green traps coated with untinted (white) fluon caught almost four times as many adult A. planipennis as Rain-X and tinted (green) fluon-coated traps and almost 33 times more beetles than untreated control traps. Purple multifunnel traps generally caught much lower numbers of A. planipennis adults than green traps, and trap catch on them was not affected by differences in the type of coating applied. However, trap coating was necessary as untreated control purple traps caught significantly less beetles than traps treated with Rain-X and untinted or tinted (purple) fluon. Proportions of male beetles captured were generally much higher on green traps than on purple traps, but sex ratios were not affected by trap coating. In 2012, a new shade of purple plastic, based on a better color match to an attractive purple paint than the previously used purple, was used for trapping assays. When multifunnel traps were treated with fluon, green traps caught more A. planipennis adults than both shades of purple and a prism trap that was manufactured based on the same color match. Trap catch was not affected by diluting the fluon concentration applied to traps to 50% (1:1 mixture in water). At 10%, trap catch was significantly lowered.

Drosophila suzukii Matsumura (Diptera: Drosophilidae), commonly referred to as the spotted wing drosophila, is an exotic species that has proven a troublesome pest of fruit production in the United States. The fly targets small fruit and thus represents a concern for the U.S. cranberry industry. Two studies were conducted to assess whether cranberries may serve as hosts for D. suzukii. In the first study, the suitability of ripe, unripe, and over-ripe cranberries were assayed by examining adult oviposition and larval development in no-choice trials. In the second study, wounded and unwounded fruit were examined as potential hosts in choice and no-choice trials. Our first study showed that ripe, unripe, and over-ripe cranberries were unsuitable hosts (few eggs were laid, with no surviving puparia). In the wounded and unwounded berry study, no larvae survived to adulthood among unwounded berries. Within wounded fruit, D. suzukii readily fed and developed into adults. Together, these results suggest that unwounded cranberries—whether ripe, unripe, or over-ripe—are unsuitable as hosts for D. suzukii. Wounded rotting cranberries, however, can serve as hosts. Across the landscape, cranberry marshes with rotting fruit may contribute to D. suzukii source-sink dynamics.

The Turkestan cockroach, Blatta lateralis (Walker), has become an important invasive species throughout the southwestern United States and has been reported in the southern United States. It is rapidly replacing the oriental cockroach, Blatta orientalis (L.), in urban areas of the southwestern United States as the most important peri-domestic species. They typically inhabit in-ground containers such as water meter, irrigation, and electrical boxes, raises of concrete, cracks and crevices, and hollow block walls. On occasion, they will invade dwellings. At 26.7°C, male and female nymphs developed into adults in an average of 222 and 224 d, respectively. Both males and females had five nymphal instars. Adult females deposited up to 25 oothecae. The oothecae averaged 16.8 eggs and 13.9 nymphs emerged per egg capsule, resulting in an 82.7% hatch rate. Adults lived for at least 612 d.Twoparameters that might contribute to the success of Turkestan cockroaches compared with oriental cockroaches are that the developmental period of the nymphs of Turkestan cockroaches are shorter and adult female Turkestan cockroaches produce considerably more oothecae than do oriental cockroaches. These may explain the observations by Pest Management Professionals that Turkestan cockroaches are displacing oriental cockroaches in outdoor habitats throughout the southwestern United States.

Bed bugs were exposed to freezing temperatures for various exposure times to determine cold tolerance and mortality estimates for multiple life stages. The mean supercooling point for all bed bug life stages ranged from -21.3°C to -30.3°C, with the egg stage reporting the lowest value. A probit analysis provided a lower lethal temperature (LLT₉₉) of -31.2°C when estimates from all life stages were combined, demonstrating that all stages of bed bugs are not capable of surviving temperatures below body freezing and are therefore freeze intolerant. At conditions above the LLT₉₉, bed bug mortality depended on temperature and exposure time at temperatures above LLT₉₉. Based on our model estimates, survival was estimated for temperatures above -12°C even after 1 wk of continuous exposure. However, exposure to temperatures below -13°C will result in 100% mortality in d to ensure mortality of all life stages. Unfortunately, sublethal exposure to lower temperatures did not prevent subsequent feeding behavior in surviving stages. Practical recommendations for management of potentially infested items are discussed.

The reliability of the capture probability equilibrium model developed by Su and Lee (2008) for population estimate was tested in three-directional extended foraging arenas connecting to large Plexiglas cubes (96 by 96 by 96 cm) containing ≈100,000–400,000 workers of the Formosan subterranean termite, Coptotermes formosanus Shiraki. After the release of marked termites in the arenas, the capture probability was averaged for three directions at equal distance from the release point. The daily data of directionally averaged capture probability were subject to a linear regression with distance as the independent variable to identify the capture probability equilibrium. When the daily data produced significant regressions with regression slope |b| ≤ 0.05 or |b| ≈ 0.05, the directionally averaged capture probability was considered to have reached equilibrium, and the regression intercept was used in the Lincoln index to derive the population estimate. Of the four laboratory colonies tested, three met the criteria, and the equilibrium models yielded population estimates that were not significantly different from the known numbers of workers in the arenas.

The plataspid Megacopta cribraria (F.), which was recently introduced to the United States, forms nuisance aggregations on the exteriors of homes when it seeks overwintering sites in the fall. Little to no published information is available on the efficacy of insecticides labeled for professional use and exterior applications on homes and other structures against this insect. In a series of three experiments, we evaluated the residual efficacy of nine insecticides incorporating pyrethroid, neonicotinoid, and oxadiazine active ingredients on surfaces composed of five exterior building materials (vinyl soffit, brick, painted and unfinished plywood, and metal) at rates labeled for use in structural perimeter applications. Pyrethroids and pyrethroid-neonicotinoid mixes were broadly effective, resulting in 100% mortality or knockdown within 24 h in most cases. The neonicotinoid dinotefuran performed similarly on metal and vinyl surfaces, but its residual efficacy was reduced on more porous brick and wood surfaces. The oxadiazine indoxacarb acted more slowly than the other materials, but its performance was maintained on porous surfaces. Overwintering adults of M. cribraria were generally susceptible to the broad-spectrum insecticides most commonly used for exterior applications to homes and other structures.

The carmine spider mite, Tetranychus cinnabarinus (Boisduval), is one of the most important pests in agricultural industry. Pyrethroid insecticide has been used to control insects and mites worldwide. However, the intensive use of pyrethroid insecticide resulted in the development of resistance, which has mainly been induced by a variety of point mutations responsible for voltage-gated sodium channel (VGSC) insensitivity and has become the biggest obstacle to sustain the use of pyrethroid insecticide. In this study, we cloned cDNA full length of the para-homologous sodium channel gene from T. cinnabarinus named TC-vgsc. The complete open reading frame of TC-vgsc contains 6,579 nucleotides, encoding 2,193 amino acids. A point mutation, F1538I, was identiÞed from both the DNA and RNA sequences of VGSC in fenpropathrin- resistant strain, which developed ≈100-folds resistance against fenpropathrin. The result indicated the F1538I kdr mutation underwent DNA mutation events rather than RNA editing. Single nucleotide polymorphisms detection of F1538I mutation from indoor susceptible strain, fenpropathrin-resistant strain, and seven Þeld populations found that this mutation appeared in all the strains (populations), but the frequency of mutation was closely related to the resistance level, with a r² value of 0.665 (P < 0.05), that is, the higher the resistance level, the larger the mutation frequency. These results demonstrated that the F1538I mutation in the kdr gene can be used as a molecular marker for fenpropathrin-resistance monitoring in Þeld T. cinnabarinus populations.

The western bean cutworm, Striacosta albicosta (Smith) (Lepidoptera: Noctuidae), is a destructive insect pest of dry beans and corn within its native range of western Nebraska and eastern Colorado. However, since the initiation of an eastward range expansion of S. albicosta in the late 1990s, economic damage has been observed in the Midwest, and the species has now reached the Atlantic Coast and Quebec. Economic damage to corn occurs by larval feeding on ears, which is not controlled by commercial transgenic hybrids that express Bacillus thuringiensis (Bt) Cry1Ab, but partial control is observed by corn varieties that express Cry1 F toxins. Inadequate protocols for laboratory rearing of S. albicosta have hindered controlled efficacy experimentation in the laboratory and field.Wereport an S. albicosta rearing methodology used to maintain a laboratory colony for 12 continuous generations. Rearing procedures were adapted for Bt toxin diet-overlay assays, revealing that S. albicosta larvae exposed to Bt toxin for 14 d were insensitive to Cry1Ab concentrations up to 25,000 ng/cm2. In contrast, neonates exposed to Cry1 F toxin at ≥250 ng/cm2, showed reduced developmental rates, with estimated effective concentrations of EC₅₀=1,187.5 ng/cm² and EC₉₅=10,000.5 ng/cm2. The ability to mass produce this pest insect will enhance fundamental research, including evaluation of control tactics and toxin susceptibility.

The cowpea weevil, Callosobruchus maculatus F. (Coleoptera: Bruchidae), can cause up to 100% yield loss of stored cowpea seeds in a few months in West Africa. Genes expressing toxins delaying insect maturation(MDTs)are available for genetic engineering.Asimulation model was used to investigate the possible use of MDTs for managing C. maculatus. Specifically, we studied the effect of transgenic cowpea expressing an MDT, an insecticide, or both, on the evolution of resistance by C. maculatus at constant temperature. Transgenic cowpea expressing only a nonlethal MDT causing 50–100% maturation delay did not control C. maculatus well. Mortality caused by a maturation delay improved the efficacy of transgenic cowpea expressing only a lethal MDT, but significantly reduced the durability of transgenic cowpea. Transgenic cowpea expressing only a lethal MDT causing 50% maturation delay and 90% mortality controlled C. maculatus better than one expressing only a nonlethal MDT, but its durability was only 2 yr.Weconcluded that transgenic cowpea expressing only an MDT has little value for managing C. maculatus. The resistance by C. maculatus to transgenic cowpea expressing only an insecticide rapidly evolved. Stacking a gene expressing a nonlethal MDT and a gene expressing an insecticide in transgenic cowpea did not significantly improve the durability of an insecticide, but stacking a gene expressing a lethal MDT and a gene expressing an insecticide in transgenic cowpea significantly improved the durability of an insecticide and an MDT. We also discussed this approach within the idea of using transgenic RNAi in pest control strategies.

Emergence phenology and fitness attributes of several Colorado potato beetle, Leptinotarsa decemlineata (Say), populations were measured under field and greenhouse conditions. Anecdotal observations by producers and pest managers in many locations of the upper Midwest increasingly suggested that select populations of Colorado potato beetle were emerging over a longer period in the spring and were less sensitive to systemic neonicotinoids in cultivated potato. These changes in emergence phenologymaybe related to changes in systemic insecticide concentration over time. Specifically, a prolonged period of adult emergence in the spring increases the potential of low-dose chronic exposure to systemic neonicotinoid insecticides in potato. In 2010 and 2011, our objectives were twofold: 1) establish a common garden experiment to compare the emergence phenology of Colorado potato beetle populations uniquely managed with variable insecticide inputs, and 2) measure postdormancy fitness of emerged adult beetles from among these selected populations. Cumulative adult emergence was modeled with logistic regression. Results from this study found no clear evidence for direct relationships between phenology and management history or resistance. Differences in reproductive capacity, sex ratio, and body size were apparent in some instances. However, these results did not uniformly correspond to one specific form of potato pest management tested here. In this study, long-term reliance on systemic insecticides for Colorado potato beetle control did not serve as a strong predictor for variable life history for selected populations in Wisconsin.

A laboratory colony of western corn rootworm, Diabrotica virgifera virgifera LeConte, was selected for resistance to transgenic maize expressing the eCry3.1Ab protein. The selected colony was developed by rearing larvae on nonelite noncommercial Bt maize expressing the eCry3.1Ab protein. After four generations, selected and control colonies were screened on eCry3.1Ab-expressing and isoline maize using greenhouse experiments. There was a significant colony × maize pedigree interaction in terms of the number of larvae recovered. There was no significant difference in the number of larvae recovered from eCry3.1Ab-expressing and isoline maize for the selected colony, whereas this difference was significant for the control colony. There was not a significant colony × maize pedigree interaction in terms of root damage, or the number of beetles recovered, but the effect of maize pedigree was significant. After four and eight generations of selection, seedling bioassays were performed. Again, there was a significant colony × maize pedigree interaction in terms of the number of larvae recovered. After 11 generations of selection, larvae from the selected colony had higher LC₅₀ values than the control colony when exposed to increasing concentrations of the eCry3.1Ab protein. The resistance ratio of the selected colony was 2.58. These data provide necessary information for understanding the potential for Bt resistance by western corn rootworm and underscores the need for insect resistance management plans for this pest.

Development of resistance to transgenic crops expressing the Cry toxin from Bacterium thuringiensis (Bt) has been the major concern for the long-term success of Bt crops. Alterations in nonbinding site proteinases and Bt toxin receptors are the two types of mechanisms responsible for Bt resistance in resistant insects. However, little is known about the relative contributions of the two types of mechanisms in the early and late phases of the development of Bt resistance. To address the relative contributions of four nonbinding site proteinases including esterase, total protease, chymotrypsin, and glutathione S-transferase in the early and late phases of the development of Cry1Ac resistance, we analyzed the relationships between nonbinding site proteinases and resistance of three groups of Helicoverpa armigera H*ubner (Lepidoptera: Noctuidae) strains with different resistance levels because of different geographic origins and selection pressures. Positive correlation (esterase, glutathione-S-tranferases [GST], and chymotrypsin) and negative correlation (total midgut protease) were observed within the low to moderate group II resistant strains. Such correlations were less obvious within the low to moderate group III resistant strains because of only threefold differences in LC₅₀ values. Relative to the unselected susceptible 96S strain, the two highly resistant group I resistant strains BtI and BtR have the same amounts of esterase, GST, and chymotrypsin and disproportionally decreased the amount of total midgut protease. Overall, the low to moderate resistant strains had the lowest amount of the nonbinding site proteinases. The results obtained suggest that alternations in the nonbinding site proteinases probably can only confer low to moderate levels of resistance and thus are enriched in the early phase of the development of Cry1Ac resistance.

In recent years, the common bed bug, Cimex lectularius L. (Hemiptera: Cimicidae), became a major public health concern in urban communities. Bed bugs are notoriously difficult to control, and their bites are not tolerated by most people. The public has an urgent need for materials and methods to reduce bed bug introduction and bites during work, travel, or sleep. A repellent product will help achieve these goals by discouraging and preventing bed bugs from moving to a protected area. We evaluated the repellency of three commercially available insect repellent or control materials and five nonregistered materials with the goal of identifying safe and effective bed bug repellents. The two commercial repellent products that contained 7% picaridin or 0.5% permethrin had little repellency against bed bugs. N,N-diethyl-m-toluamide (DEET), the most commonly used insect repellent, provided a high level of repellency against bed bugs. When a host cue (carbon dioxide) was present, theminimum DEET concentration to repel ≥94% of the bed bugs for a 9-h period was 10%. The longevity of repellency of DEET was concentration dependent. At 25% concentration, DEET-treated fabric surface remained highly repellent to bed bugs for a 14-d period. However, DEET has a strong smell and dissolves certain plastic materials. Therefore, we evaluated several odorless, noncorrosive, and potentially effective repellents. Isolongifolenone and isolongifolanone, two natural products and recently reported insect repellents, exhibited strong repellent property against bed bugs but at significantly lower levels than DEET. Three novel potential repellent compounds discovered by Bedoukian Research Inc. (Danbury, CT) exhibited similar level of repellency and longevity as DEET for repelling bed bugs. These nonirritant and odorless compounds are promising candidates as alternatives to DEET for reducing the spread of bed bugs and bed bug bites.

The contact toxicity of four insecticide formulations (deltamethrin, fipronil, fenitrothion, and imidacloprid) applied on three different substrates (tile, plywood, and concrete) against the adult rove beetle, Paederus fuscipes Curtis, was evaluated. The relative order of speed of killing effects was as follows: deltamethrin > imidacloprid > fipronil > fenitrothion. Although deltamethrin showed the fastest action against P. fuscipes, the recovery rate of rove beetles at 48 h posttreatment was moderate (≈ 25%) on the tile surface to high (≈80%) on the plywood surface. Thus, it is likely that the insects did not pick up the lethal dose especially on porous surfaces. In contrast, fipronil demonstrated delayed toxicity that might promote maximal uptake by the insects. More than 80% mortality was registered for tile and plywood surfaces up to 4wk after exposure. High mortality (almost 100%) was recorded for imidacloprid-exposed P. fuscipes at 48 h posttreatment, but only on the tile surface. Among the four insecticides tested, fenitrothion was the least effective against P. fuscipes because low percentage to no mortality was recorded in the fenitrothion treatment.

The success of sterile males in area-wide sterile insect technique (aw-SIT) programs against Ceratitis capitata (Wiedemann) is currently measured by using indirect methods as the wild:sterile male ratio captured in monitoring traps. In the past decade, molecular techniques have been used to improve these methods. The development of a polymerase chain reaction-restriction fragment-length polymorphism-based method to identify the transfer of sterile sperm to wild females, the target of SIT, was considered a significant step in this direction. This method relies on identification of sperm by detecting the presence of Y chromosomes in spermathecae DNA extract complemented by the identification of the genetic origin of this sperm: Vienna-8 males or wild haplotype. However, the application of this protocol to aw-SIT programs is limited by handling time and personnel cost. The objective of this work was to obtain a high-throughput protocol to facilitate the routine measurement in a pest population of sterile sperm presence in wild females. The polymerase chain reaction-restriction fragment-length polymorphism markers previously developed were validated in Mediterranean fruit fly samples collected from various locations worldwide. A laboratory protocol previously published was modified to allow for the analysis of more samples at the same time. Preservation methods and preservation times commonly used for Mediterranean fruit fly female samples were assessed for their influence on the correct molecular detection of sterile sperm. This high-throughput methodology, as well as the results of sample management presented here, provide a robust, efficient, fast, and economical sterile sperm identification method ready to be used in all Mediterranean fruit fly SIT programs.

The Asian corn borer, Ostrinia fumacalis (Guenée), is a major pest of maize in China. Transgenic Bt maize could provide an effective way to control this pest. However, the potential of resistance evolution has been documented in the laboratory—a Cry1Ab-resistant strain of Asian corn borer (Asian corn borer-AbR) could survive well on two Bt maize events, that is, MON810 and Bt11. Pyramided transgenic crops with multiple dissimilar Bt insecticidal proteins offer a superior route for pests control compared with that with one Bt single gene. In this study, two novel transgenic Bt maize events (N30 and V3), which contained a fused gene cry1Ab/cry2Aj and cry1Ab/vip3DA, respectively, were evaluated for their efficacy on protection against Cry1Ab-susceptible Asian corn borer (Asian corn borer-BtS) as well as their potential for dealing with the Asian corn borer-AbR. In laboratory bioassay, no neonate larvae of Asian corn borer-BtS fed on the whorl leaves, tassels, husks, silks, and kernels of N30 and V3 could survive at 96 h after infestation. In contrast, only 2.0–8.7% larvae died as they fed on non-Bt maize tissues. As Asian corn borer-AbR neonate larvae fed on N30 and V3 silks and kernels, 95.0% even more larvae were killed at 96 h after infestation, and all died at 168 h after infestation, while 10.0–11.67% larvae survived on non-Bt control. In the field test under artificial infestation at middle whorl leaf and silking stages of maize, there were no significant leaf, silk, and stalk damage on Bt maize plants by comparison with severe leaf feeding, stalk born, and ear damage in control. In addition, the expression profiles of a fused protein of Cry1Ab/Cry2Aj or Cry1Ab/Vip3DA in different tissues of N30 and V3 were also confirmed. In conclusion, it is clear that both Bt maize events (N30 and V3) show great potential for protecting maize from attack by Asian corn borer that has resistance to Cry1Ab protein.

Crucifer-feeding flea beetles, Phyllotreta spp., are chronic insect pests in Canadian prairie canola production. Multiple laboratory and field feeding bioassays were conducted to determine the susceptibility of a wide range of crucifer species, cultivars, and accessions to feeding by flea beetles with the goal of discovering sources of resistant germplasm. In 62 bioassays of 218 entries, no consistent decreased feeding by flea beetles was seen on any entries of Brassica carinata A. Braun, Brassica juncea (L.) Czern., Brassica napus L., or Brassica rapa L. There was reduced feeding on condiment mustard Sinapis alba L. lines but not on canola-quality lines with reduced amounts of glucosinolates, which were fed on at levels equal to B. napus. Analyses of glucosinolate content found decreased quantities of hydroxybenzyl and butyl glucosinolates in preferred canola-quality S. alba lines and increased levels of hydroxybutenyl glucosinolates compared with levels in condiment S. alba lines. Eruca sativa Mill. was an excellent flea beetle host; Camelina sativa (L.) Crantz lines experienced little feeding. Lines of Crambe abyssinica Hochst. ex R. E. Fries and Crambe hispanica L. had reduced feeding levels compared with Brassica entries, but Crambe glabrata DC did not. The results indicate possible sources of resistance to Phyllotreta flea beetles, while highlighting the complicated roles that glucosinolates may play in Phyllotreta host preference.

Oxidative enzymes are one of many key players in plant tolerance responses and defense signaling pathways. This study evaluated gene expression of four buffalograss transcripts (two peroxidases, a catalase, and a GRAS (gibberellic acid insensitive [GAI], repressor of GAI, and scarecrow) and total peroxidase activity in response to western chinch bug (Blissus occiduus Barber) feeding in susceptible and resistant buffalograsses (Buchloë dactyloides (Nuttall) Engelmann). Basal levels of all four transcripts were consistently higher in the resistant buffalograss when compared with the susceptible genotype, which suggests important physiological differences exist between the two buffalograsses. The four defense-related transcripts also showed differential expression between infested and control plants for both the resistant and susceptible buffalograsses. Differences in total peroxidase activity were also detected between control and infested plants, and basal peroxidase activity was higher in the resistant genotype. Overall, this study indicates that elevated basal levels of specific peroxidases, catalases, and GRAS may be an effective buffalograss defense strategy against chinch bug feeding and other similar biotic stresses.

The Rag1 gene confers antibiotic resistance to soybean aphid, Aphis glycines Matsumura (Hemiptera: Aphididae), and in 2010, varieties expressing Rag1 were released for commercial use in the United States. We do not know how Rag1 varieties will influence the broader community of defoliating insects that inhabit soybean fields. In 2010 and 2011, the preference and performance of pest insects that defoliate soybeans [Glycines max (L.) Merr] were tested using Rag1 and aphidsusceptible varieties. Three coleopterans and four lepidopterans were used: northern corn rootworm, Diabrotica barberi Smith & Lawrence (Coleoptera: Chrysomelidae); southern corn rootworm, Diabrotica undecimpunctata howardi Barber (Coleoptera: Chrysomelidae); bean leaf beetle, Ceratoma trifurcata Förster (Coleoptera: Chrysomelidae); fall armyworm, Spodoptera frugiperda (J. E. Smith) (Lepidoptera: Noctuidae); corn earworm, Helicoverpa zea (Boddie) (Lepidoptera: Noctuidae); soybean looper, Chrysodeix includens (Walker) (Lepidoptera: Noctuidae); and velvetbean caterpillar, Anticarsia gemmatalis Hübner (Lepidoptera: Noctuidae). The preference of insects was evaluated in choice and no-choice tests using Rag1 and susceptible soybeans. Lepidopterans also were evaluated on Rag1 leaves using four nutritional indices: relative growth rate, approximate digestibility, and efficiency of conversion of ingested material. In the majority of preference tests, no effect of Rag1 was detected, and in cases where preferences were found, there was no consistent pattern of preference for Rag1 vs. susceptible leaf tissue. Helicoverpa zea demonstrated a preference for resistant leaf tissue, but this was dependent on the genetic background of the variety. Evaluations of nutritional indices indicated that three species of Lepidoptera, S. frugiperda, H. zea, and A. gemmatalis, displayed reduced conversion efficiency for Rag1 soybeans, suggesting effects of antibiosis.

Plant expression of the entomopathogenic bacteria Bacillus thuringiensis cry gene has reduced the damage created by insect pests in several economically important cultures. For this study, we have conducted genetic transformation of the indica rice ‘IRGA 424,’ via Agrobacterium tumefaciens, using the B. thuringiensis cry1Aa and cry1B genes, with the objective of obtaining rice plants resistant to the insect pests from this culture. The gene constructions harbor the promoters maize proteinase inhibitor and ubiquitin. The results showed that high concentration of the hormone 2,4-dichlorophenoxyacetic acid and agarose as the gelling agent helped the production of embryogenic calli for the analyzed cultivar. More than 80% of the obtained transformed plants revealed the integration, using polymerase chain reaction, of the cry1Aa and cry1B genes. Analysis of the expression of the heterologous protein by Western blotting revealed the expression of the Cry1B δelta-endotoxin in IRGA 424 plants transformed with the ubiquitin promoter. Data showed the production and dissemination of a high number of embryogenic calli in addition to obtaining plants transformed with the cry1Aa and cry1B genes until the reproductive phase. The feed bioassays with the transformed plants and Spodoptera frugiperda (JE Smith) larvae indicated high rates of mortality to the insect target. The highest corrected mortality rate achieved under laboratory conditions with Bt-rice plants transformed with the cry1B and cry1Aa genes was 94 and 84%, respectively. Thus, our results demonstrated the great potential of transformed Bt-rice plants in controlling the damage caused by these insect pests in rice paddy fields.

The incidence and host associations of Russian wheat aphid were investigated in the wheat-growing areas of South Africa from 2009 to 2011. Most Russian wheat aphid samples were collected on dryland wheat, while few samples were collected on irrigation wheat. Volunteer wheat and rescue grass were the preferred alternative host plants to cultivated wheat for all three biotypes. NoRWASA1samples were collected from oats, butRWASA2seemed to be able to survive successfully on oats, with 12.26% of the total RWASA2 samples collected on oats and 2.83% RWASA2 samples on wild oats. The intrinsic rate of population increase (r_m) has often been used as an index of herbivore performance, and alternative host suitability can be quantified using growth rate parameters, such as the intrinsic rate of increase. The r_m was determined for the three South African biotypes—RWASA1, RWASA2, and RWASA3—on seven different host plants. Russian wheat aphid biotypes showed a positive intrinsic rate of increase on all host plants tested, indicating that these host plants were all suitable hosts to support populations of all three biotypes. The r_m on TugelaDn, which is resistant to RWASA1 but susceptible to RWASA2 and RWASA3, was significantly higher for RWASA3 and lowest for RWASA1. The r_m for RWASA2 and RWASA3 was significantly lower on TugelaDn5, which is resistant to these two biotypes. The r_m for RWASA2 and RWASA3 was significantly higher than for RWASA1 on both oats and wild oats. Aphid infestation of winter wheat in the spring may be directly influenced by their success and abundance in noncultivated host plants between harvest and emergence of the cultivated wheat. Therefore, it is important to consider the success of different Russian wheat aphid biotypes on host plant alternatives to cultivated cereals when planning a management strategy for Russian wheat aphid in an area.

Onion thrips (Thrips tabaci Lindeman) has become a significant pest of cabbage (Brasssica oleracea L.) in regions with a dry continental climate. Thrips-resistant cabbage varieties have been developed in breeding programs, but the mechanisms of resistance remain largely unknown. Antixenosis, one of the three resistance mechanisms, may play a role but no plant trait has been identified as a source of antixenosis. A series of studies were conducted to identify resistance mechanisms in this insect—crop interaction and to seek plant traits that were correlated to resistance. In this first article of the series, the result of studying antixenosis and overall resistance of cabbage and the correlation between antixenosis and light reflectance characteristics are reported. There were distinct differences in the overall resistance to thrips between the six cabbage varieties studied. There were more pronounced differences between varieties based on the number of damaged head leaves compared with the use of damage ratings as a measure of overall resistance. Varieties also differed in their level of antixenosis; proportional abundance of thrips adults on head-forming leaves was more closely correlated to overall resistance of cabbage than actual thrips numbers. Some of the variables computed from the recorded reflectance spectra of cabbage were correlated to thrips abundance on head-forming leaves only in the first but not in the second year of this study, suggesting that either spectral characteristics do not affect antixenosis or other variables may affect thrips' responses to spectral cues. Furthermore, multiple spray applications of a kaolin particle-based product significantly changed the light reflectance characteristics of cabbage, but it did not reduce the actual thrips abundance on head-forming leaves.

We developed a binomial sequential decision plan that classifies the economic status of nonviruliferous pea aphids, Acyrthosiphon pisum (Harris) (Hemiptera: Aphididae), in commercial dry peas, Pisum sativum L. (Fabales: Fabaceae), in the Palouse region of northern Idaho and eastern Washington state. Relationships between mean pea aphid density per plant (x) and the proportion of aphid-infested plants (P_i) were determined by in situ visual counts of 100 plants on each of 27 seasonal dates during 2011 from early vegetative plant growth (stage V105) to late reproductive growth (stage R207) at two field sites near Moscow, ID. The best-fit Nachman model P_i = 1 - exp(-0.3616 x^0.808) was used to restate the limits of noneconomic and economic infestations from one and three aphids per plant to 30 and 58% aphid-infested plants, respectively. Sequential decision plans were computed using the stop-line formulas of Waters for Wald's Sequential Probability Ratio Test. Validation of the sequential decision plan by simulated sampling from the 2011 data as well as from six commercial fields sampled during 2012 showed that when observed field densities either exceeded the economic injury level or were less than one third the economic injury level, the plan correctly classified aphid economic status in >99% of the resampling trials. Practical implementation of the plan is discussed.

The polyphagous predatory ladybird Cheilomenes sexmaculata (F.) (Coleoptera: Coccinellidae) is distributed throughout southern China and has been investigated as a potential biological control agent against herbivorous insects in various agroecosystems. In the current study,weevaluated the preimaginal development, eclosion rate, reproduction, fertility, adult longevity, and prey consumption of C. sexmaculata under five temperature and five photoperiod regimens. The results showed that preadult developmental duration decreased significantly with increasing temperature and amount of daylight. Adult eclosion rate was highest at 35°C and under conditions of complete darkness. Higher temperatures shortened the duration of copulation and preoviposition, prolonged the duration of oviposition, and increased the level of fecundity. Hatchability was highest at 30°C . By contrast, the shortest copulation and oviposition duration and lowest level of fecundity and hatchability occurred with a completely dark photoperiod. Temperature and the gender of C. sexmaculata influenced adult longevity. In addition, there was a significant interaction effect of photoperiod and gender on adult longevity. Furthermore, prey consumption by fourth instar larvae and adult females both increased with increasing temperature and photoperiod. Our results reveal the high thermal and light sensitivities of C. sexmaculata, which highlight the importance of environment regulation in the mass rearing of this natural enemy for application as a biological control in agroecosystems in China.

Fipronil is a widely used insecticide for termite control. Although transfer of fipronil among termite cohorts has been investigated in previous studies, no study has yet focused on the influence of termite group size (density) on horizontal transfer. In this study, the mortality of donor and recipient Coptotermes formosanus Shiraki (Isoptera: Rhinotermitidae) was compared among groups of 10, 25, and 50 workers. Most donor termites were dead within 20 h. There was a significantly higher mortality of recipient termites starting at 44 h when in bigger groups. LT₅₀ and LT₉₀ of recipient termites decreased with increase in group size, being significantly shorter in groups of 50 termites compared with groups of 10 termites. Moreover, the variance (within-group difference) of recipient mortality and lethal time estimations was lowest in the groups of 50 termites, indicating a more uniform horizontal transfer of fipronil by termites in bigger groups. Our findings suggest that group size has an influence on fipronil transfer among C. formosanus workers and should be considered as a variable of importance.