In Uruguay, colonies of honey bees moving to Eucalyptus grandis plantation in autumn habitually become infected with the microsporidian Nosema ceranae, a parasite that attacks the digestive system of bees. Beekeepers attributed to N. ceranae depopulation of the colonies that often occurs at the end of the blooming period, and many use the antibiotic fumagillin to reduce the level of infection. The aim of this study was to compare the effectiveness of four different fumagillin treatments and determine how this antibiotic affects the strength of the colonies during the winter season. The colonies treated with fumagillin in July showed less spore load at the end of applications, being the most effective the following treatments: the four applications sprayed over bees of 30 mg of fumagillin in 100 ml of sugar syrup 1:1, and four applications of 90 mg of fumagillin in 250 ml of sugar syrup 1:1 using a feeder. However, 2 month after the treatment applications, the colonies treated with fumagillin were the same size as the untreated colonies. In September, the colonies treated and not treated with fumagillin did not differ in colony strength (adult bee population and brood area) or spores abundance. Our study demonstrates that fumagillin treatment temporarily decreased the spore load of N. ceranae, but this was not reflected in either the size of the colonies or the probability of surviving the winter regardless of the dose or the administration strategy applied. Given the results obtained, we suggest to not perform the pharmacological treatment under the conditions described in the experiment.

Contracted commercial beekeeping operations provide an essential pollination service to many agricultural systems worldwide. Increased use of genetically engineered crops in agriculture has raised concerns over pollinator-mediated gene flow between transgenic and conventional agricultural varieties. This study evaluated whether contracted migratory beekeeping practices influence transgenic pollen flow among spatially isolated alfalfa fields. Twelve honey bee (Apis mellifera L.) colonies were permitted to forage on transgenic alfalfa blossoms for 1 wk in Touchet, WA. The hives were then transported 112 km to caged conventional alfalfa plots following one and two nights of isolation (8 and 32 h, respectively) from the transgenic source. Alfalfa seed harvested from the conventional plots was assessed for the presence of the transgene using a new seedling germination assay. We found that 8 h of isolation from a transgenic alfalfa source virtually eliminated the incidence of cross-pollination between the two varieties.

Honey bee wintering in a wintering building (indoors) with controlled microclimate is used in some cold regions to minimize colony losses due to the hard weather conditions. The behavior and possible state of bee colonies in a dark room, isolated from natural environment during winter season, was studied by indirect temperature measurements to analyze the expression of their annual rhythm when it is not affected by ambient temperature, rain, snow, wind, and daylight. Thus, the observed behavior in the wintering building is initiated solely by bee colony internal processes. Experiments were carried out to determine the dynamics of temperature above the upper hive body and weight dynamics of indoors and outdoors wintered honey bee colonies and their brood-rearing performance in spring. We found significantly lower honey consumption-related weight loss of indoor wintered colonies compared with outdoor colonies, while no significant difference in the amount of open or sealed brood was found, suggesting that wintering building saves food and physiological resources without an impact on colony activity in spring. Indoor wintered colonies, with or without thermal insulation, did not have significant differences in food consumption and brood rearing in spring. The thermal behavior and weight dynamics of all experimental groups has changed in the middle of February possibly due to increased brood-rearing activity. Temperature measurement above the upper hive body is a convenient remote monitoring method of wintering process. Predictability of food consumption in a wintering building, with constant temperature, enables wintering without oversupply of wintering honey.

The genetically modified strain of Ceratitis capitata (Wiedemann) VIENNA 8 1260 has two morphological markers that exhibit fluorescence in body and sperm. To assess the feasibility of its use in area-wide integrated pest management (AW-IPM) programs using the sterile insect technique, its rearing performance and quality control profile under small, medium, and large scales was evaluated, as well as in field cages. The VIENNA 8 1260 strain had a lower yield than the control strains, VIENNA 8 with D53 inversion (VIENNA 8) and without D53 inversion (VIENNA 8 D53-). At mass-rearing scale, yield gradually increased in three generations without reaching the control strain values. The VIENNA 8 1260 strain was stable in the genetic sexing mechanism (>99.9%) and expression of fluorescence (100%). In field cages, the VIENNA 8 1260 males reduced the mating potential of wild males in the same magnitude as the VIENNA 8, when evaluated in independent cage tests. However, the relative sterility index and the strain male relative performance index of VIENNA 8 1260 males were significantly lower than those of the VIENNA 8. There were no significant differences in longevity of these strains. The potential application of the VIENNA 8 1260 in AW-IPM programs is further discussed.

Aphelinus mali (Haldeman) is an effective natural enemy used in China to control woolly apple aphid. Previous studies have found that populations of A. mali in China fall into two distinct genetic clades. We found that one of these, the Shandong clade, is more effective as a biological control agent than the Liaoning clade. The control ability of the Shandong clade of A. mali (a/Th = 2.447) was found to be stronger than that of the Liaoning clade (a/Th = 1.278); the search parameter (Q) and the mutual interference parameter (m) of the Shandong clade (0.1166, 0.2567) were both significantly higher than that of the Liaoning clade (0.076, 0.185). The egg production and life (64.4 ± 10.44 eggs and 16.26 ± 1.04 (female), 13.54 ± 0.75 (male) days, respectively) of the Shandong clade were both significantly higher than they were for the Liaoning clade (30.67 ± 4.02 eggs and 9.34 ± 0.67 (female), 7.64 ± 0.48 (male) days, respectively), and the Shandong clade had a longer oviposition period for one oviposition (Shandong 86.6 s, Liaoning 61.4 s). We expect, in Shandong Province, the pest control ability of the Shandong clade of A. mali to be better than the Liaoning clade.

Combinations of entomopathogenic nematodes Steinernema longicaudum X-7 and Heterorhabditis bacteriophora H06 with chlorantraniliprole, diflubenzuron, and imidacloprid insecticides at different rates for the control of the white grub, Holotrichia oblita Faldermann (Coleoptera: Scarabaeidae), were evaluated both in the laboratory and in peanut fields. In the laboratory, the combinations had a synergistic or additive effect on the second-instar larvae of H. oblita and caused faster mortality than one nematode species or insecticide alone. Heterorhabditis bacteriophora–chlorantraniliprole and H. bacteriophora–imidacloprid showed synergistic effects on the larvae. When higher concentrations of the insecticides were combined with nematodes, the stronger synergistic effects were found. In peanut fields, S. longicaudum–imidacloprid, H. bacteriophora–imidacloprid, or H. bacteriophora–chlorantraniliprole also showed synergistic effects against the larvae. The three nematode–insecticide combinations produced similar percentage reductions of the grub larvae and less percentages of injured legumes, compared with the chlorpyrifos treatment. Cost–benefit analysis showed that H. bacteriophora 5.0 × 10³ infective juveniles (IJs) per plant (equal to 7.5 × 10⁸ IJ ha^–1) combined with imidacloprid at the recommended concentration is a practical strategy for the practitioner to manage the white grubs in the peanut production.

Flupyradifurone and sulfoxaflor present novel insecticide chemistries with particular efficacy against aphids, and the recent emergence of sugarcane aphid, Melanaphis sacchari (Zehntner), as a pest of sorghum in the United States has resulted in their widespread use. We examined their toxicity to Hippodamia convergens Guerin-Meneville, an important aphid biocontrol agent. We exposed beetles to topical applications of the field rate (FR) of these insecticides, fed them contaminated food (eggs of Ephestia kuehniella Zeller), and gave firstinstar larvae 24-h exposures to leaf residues. More than half of fourth-instar larvae receiving topical applications of sulfoxaflor at FR survived, whereas flupyradifurone at 0.1× FR caused 90% mortality. Adults survived topical treatments better than larvae and without measurable mortality, except flupyradifurone at FR, which killed more than 80% of beetles. Survivors of all treatments had fertility similar to controls, whether treated as larvae or adults. Ingestion of contaminated food caused significant mortality in all treatments (15–40% for adults and 55–85% for larvae), with no significant differences between insecticides at FR. Leaf residues of sulfoxaflor at 1.0 and 2.0× FR caused approximately 60 and 80% mortality of first instars, respectively, whereas flupyradifurone at 0.1 and 1.0× FR caused > 90% mortality. Although sulfoxaflor was less toxic to H. convergens than flupyradifurone, the tested FR of flupyradifurone has now been reduced by half. We conclude that neither insecticide appears as toxic as other nicotinic acetylcholine receptor agonists, and that both materials are compatible with integrated pest management programs for M. sacchari.

European corn borer, Ostrinia nubilalis (Hübner) (Lepidoptera: Crambidae), is the main pest causing damage to sweet corn in North America. Conventional management with multiple use of insecticides is a common practice for processing sweet corn. In Canada, the use of Trichogramma spp. began in the 1990s, but the adoption of this approach for European corn borer management is still limited to the fresh market of sweet corn. Trichogramma ostriniae (Peng & Chen) has great potential as a biological control agent for large areas such as in processing sweet corn. The objective of this study was to evaluate an economically and environmentally sustainable alternative to insecticides for controlling European corn borer populations in processing sweet corn. During the growing season, the mean number of larvae decreased after insecticide (0.07 ± 0.04) and Trichogramma (1.32 ± 0.59) treatments compared with the control (2.42 ± 0.72). At harvest, damages associated with European corn borer were similar after Trichogramma (1.0 ± 0.7%) and insecticide (1.0 ± 0.6%) treatments, but significantly lower than the control (8.7 ± 3.3%). This study showed that the use of T. ostriniae can significantly decrease the pressure exerted by European corn borer and its damage on corn ears. This outcome is particularly interesting considering that it was achieved with lower doses of Trichogramma, a lower number of releases, and on large crop areas, compared with what is actually done to protect fresh market corn from European corn borer. Under these conditions, the use of Trichogramma is an economically and competitive alternative to insecticide applications.

Bactrocera dorsalis (Hendel) (Diptera: Tephritidae) is arguably the most important tephritid attacking fruits after Ceratitis capitata (Wiedemann) (Diptera: Tephritidae). In 2003 it was found in Africa and quickly spread to most of the sub-Saharan part of the continent, destroying fruits and creating regulatory barriers to their export. The insect is causing new nutritional and economic losses across Africa, as well as the losses it has caused for decades in infested areas of Asia, New Guinea, and Hawaii. This new panorama represents a challenge for fruit exportation from Africa. Phytosanitary treatments are required to export quarantined commodities out of infested areas to areas where the pest does not exist and could become established. This paper describes current phytosanitary treatments against B. dorsalis and their use throughout the world, the development of new treatments based on existing research, and recommendations for further research to provide phytosanitary solutions to the problem.

Ionizing radiation is used as a phytosanitary treatment to mitigate risks from invasive species associated with trade of fresh fruits and vegetables. Commodity producers prefer to irradiate fresh product stored in modified atmosphere packaging that increases shelf life and delays ripening. However, irradiating insects in low oxygen may increase radiation tolerance, and regulatory agencies are concerned modified atmosphere packaging will decrease efficacy of radiation doses. Here, we examined how irradiation in a series of oxygen conditions (0.1–20.9 kPa O₂) alters radiotolerance of larvae and pupae of a model lepidopteran Trichoplusia ni (Hubner) (Diptera: Noctuidae). Irradiating in severe hypoxia (0.1 kPa O₂) increased radiation tolerance of insects compared with irradiating in atmospheric oxygen (20.9 kPa O₂). Our data show irradiating pharate adult pupae at 600 Gy in moderately severe hypoxia (5 kPa O₂) increased adult emergence compared with irradiation in atmospheric oxygen (20.9 kPa O₂). Our data also show that in one of the three temporal replicates, irradiating T. ni larvae in moderately severe hypoxia (5 kPa O₂) can also increase radiotolerance at an intermediate radiation dose of 100 Gy compared with irradiating in atmospheric oxygen conditions, but not at higher or lower doses. We discuss implications of our results in this model insect for the current generic doses for phytosanitary irradiation, including the recently proposed 250 Gy generic dose for lepidioptera larvae, and temporary restriction on irradiating commodities in modified atmosphere packaging that reduces the atmosphere to < 18 kPa O_2.

Drosophila suzukii (Matsumura) (Diptera: Drosophilidae) attacks a wide range of host plants, including crops such as blueberries, cherries, caneberries, and strawberries. We evaluated the influence of three temperatures (1.1, 3.9, and 5.0 °C) and four exposure durations (6, 12, 24, and 72 h) that were selected to represent typical grower practices on survival and development time of immature D. suzukii in artificial diet and one temperature and duration (1.67 °C for 72 h) in fruit (blueberries and raspberries). Cold storage at 1.1 °C for 24 h decreased larval survival, but shorter durations generally did not affect larval survival. No eggs or young larvae survived when held for 72 h at 1.1 °C, and fewer older larvae survived after 72 h at 1.1, 3.9, and 5.0 °C than at 20 °C (control). Development time in diet was longer for all life stages following at least 12 h at any of the storage temperatures. In blueberries, no eggs survived to pupation when stored at 1.67 °C for 72 h, and survival of third instars was reduced by 41%. In raspberries, egg, second instar, and third instar survival was significantly reduced following storage at 1.67 °C for 72 h. Drosophila suzukii larval development time was shorter in raspberry than in blueberry, but it was significantly longer in both fruits when stored at 1.67 °C for 72 h. Our results indicate that cold storage can reduce survival and increase development time of immature D. suzukii, and it could be a useful part of an integrated program to manage D. suzukii infestation.

Landscape structure and diversity influence insect species abundance. In agricultural systems, adjacent crop and non-crop habitats can influence pest species population dynamics and intensify economic damage. To investigate the influence of landscape factors on stink bug damage in agricultural systems, we assessed stink bug damage from 30 processing tomato fields in the mid-Atlantic United States and analyzed landscape structure and geographic location. We found that forest shape and size, and geographic location strongly influenced stink bug damage. Landscapes with larger forest edge in southern portions of the mid-Atlantic region experienced the greatest damage, perhaps owing to the introduction of the invasive brown marmorated stink bug. We conclude that landscape structure will likely influence damage rates in nearby agricultural fields.

The mirid bug Apolygus lucorum Meyer-Dür, 1843, an omnivorous species that feeds on plants and animals, has become a major pest in China as production of Bt-cotton has grown to such a large scale. Its omnivory is likely to be critical for its success, but the digestive mechanism(s) underlying processing and adsorption of such diverse foods is relatively unknown. Here, we examined the activities of digestive enzymes of A. lucorum in the salivary gland complex and midgut and the effect of sex, age, and food source on these activities. Amylase and protease were present in the salivary gland complex and the midgut, but were higher in the salivary gland complex. Trypsin-like enzyme was also present in both organs, but chymotrypsin-like enzyme was present only in the midgut. Sex, age, and food source affected the activities of these digestive enzymes. In general, the activities of these enzymes peaked at 10 d after emergence, and amylase and protease activities were higher in female adults than in males. Of the food sources tested, green bean pods (Gb) induced the highest amylase activity, whereas Helicoverpa armigera Hübner, 1809 eggs (He) and a mixture of Gb and He induced higher activities of the trypsin-like and chymotrypsin-like enzymes. The results from food switching experiments confirmed that amylase activity could be induced by plant sources, and animal sources induced protease activity. Thus, the types and activities of digestive enzymes in A. lucorum provide the physiological basis of the pest's omnivory.

In many sugarcane plantations in Brazil, the straw is left on the soil after harvesting, and vinasse, a by-product of the production of sugar and ethanol, is used for fertigation. Our goal was to compare ant community composition and species richness in the straw mulch of sugarcane crops with the leaf litter of neighboring forests. We tested the hypothesis that ant communities in the straw mulch of vinasse-irrigated sugarcane crops and in the forest leaf litter were similar, because the combination of straw mulching and vinasse irrigation has a positive effect on soil fauna. Straw mulch and leaf litter were collected from 21 sites and placed in Berlese funnels. In total, 61 species were found in the forest leaf litter, whereas 34 and 28 species were found in the straw mulch of sugarcane fields with and without vinasse, respectively. Ant communities differed between forest and crop fields, but the species in the sugarcane straw mulch were a subset of the species found in the forest leaf litter. Although vinasse is rich in organic matter, it did not increase ant diversity. Seven feeding and/or foraging types were identified and, among the different types, surface-foraging omnivorous ants were the most prevalent in all habitats. Vinasse-irrigated sugarcane straw mulch had more predatory species than mulch from vinasse-free fields, but fewer than forest leaf litter. However, this positive effect of vinasse irrigation should be carefully evaluated because vinasse has negative effects on the environment.

This work studied 17 insecticides belonging to nucleopolyhedrovirus (NPV), Bacillus thuringiensis (Bt kurstaki and Bt aizawai), benzoylureas (insect growth regulators [IGRs]), carbamates, organophosphates, spinosyns, and diamides against larvae of Helicoverpa armigera (Hübner), invasive species in the South American continent. Larvae of different instars were fed for 7 d with untreated or insecticide-treated diets. Mortality was recorded daily for 7 d, and surviving larvae were individually weighed on the seventh day. The NPV and Bt insecticides caused 100% mortality of first-instar larvae and first-instar and second-instar larvae, respectively. However, both NPV and Bt-based products caused low mortality of third-instar larvae and did not kill older larvae. The IGR lufenuron was highly effective against all three ages of larvae tested, whereas teflubenzuron and triflumuron produced maximum 60% mortality of second-instar larvae and lower than 50% to older larvae. Thiodicarb, chlorantraniliprole, indoxacarb, chlorpyrifos, and chlorfenapyr, irrespective of tested age, caused 100% mortality of larvae, with the last two insecticides reaching 100% mortality within 2 d of feeding on the treated diet. Flubendiamide caused lower mortality but significantly affected the weight of surviving larvae, whereas neither spinosad nor methomyl produced significant mortality or affected the weight of larvae. Based on the results, the age of H. armigera larvae plays an important role in the recommendation of NPV and Bt insecticides. Furthermore, there are potential options between biological and synthetic insecticides tested against H. armigera, and recording larval size during monitoring, in addition to the infestation level, should be considered when recommending biological-based insecticides to control this pest.

Amitraz, an acaricide used to treat Varroa destructor Anderson & Trueman, is one of the most commonly detected pesticides in honey bee (Apis mellifera L.) hives. Acaricides sometimes negatively impact honey bee cognition, but potential effects of amitraz on honey bee learning have been rarely studied. We topically exposed foragers to 95th percentile field-relevant levels of amitraz and, 24 h later, tested the ability of bees to associate a sucrose reward with a conditioned odor (learning response) using the proboscis extension response (PER). We then tested the ability of the bees to retain this memory 1 h and 2 h post-conditioning. Because amitraz is thought to affect octopamine metabolism in honey bees, and because octopamine is directly related to honey bee learning and memory, we also examined effects of exposure to amitraz on octopamine levels in honey bee hemolymph. We found that acute exposure to 95th percentile doses of amitraz had no impact on honey bee learning or short-term memory as measured by PER. Concentrations of octopamine in hemolymph from our low amitraz treatment were 1.4-fold higher than control levels, but other treatments had no effect. Our results from worst-case acute exposure experiments with worker bees in the laboratory suggest that typical field-relevant (within hive) exposures to amitraz probably have little effect on honey bee learning and memory.

With the discovery of Neohydatothrips variabilis (Beach) as a vector of Soybean vein necrosis virus (Family Bunyaviridae Genus Tospovirus), a relatively new pathogen of soybean, a multiyear study was initiated in Wisconsin (2013 and 2014) and Iowa (2014 and 2015) to determine the phenology and species composition of thrips in soybean fields. Yellow sticky card traps were used to sample thrips at regular intervals in five counties within each state's primary soybean-growing region. The assemblage of species present in Wisconsin was determined in all site-years, revealing that N. variabilis and other known vectors of tospoviruses were a relatively small percentage of the total thrips captures in 2013 (1.6%) and 2014 (3.6%). A repeated measures analysis was conducted on cumulative proportion thrips capture data within each state's sampling year to investigate differences in phenology, and standardized cumulative insect days were analyzed between sampling years within each state to determine differences in the relative magnitude of populations. Distinct seasonal trends were not detected based on location, as originally hypothesized, and thrips populations varied significantly among locations and between years. These results suggest that thrips populations may be overwintering in northern climates instead of relying solely on migrations to colonize northern soybean fields.

Bactericera cockerelli (Šulc) is a common pest of solanaceous crops largely known for vectoring “psyllid yellows” in potatoes. In recent years, however, this pest has attracted considerable attention for vectoring Zebra Chip, a devastating bacterial disease that was first reported in the United States in 2004 and has spread across the southern and northwestern states, causing significant economic losses to potato growers and the industry. Management of the disease is mainly achieved by reducing the psyllid population using insecticides, including pyrethroids and neonicotinoids; however, new insecticides with different modes of action are needed to avoid the acquisition of resistance. In the current study, the immediate and residual effects of conventional and new materials were tested under greenhouse conditions against adults and nymphs. Cyantraniliprole at a high rate and spinetoram showed the highest immediate and residual activity against adults, whereas cyantraniliprole and oxamyl (low and high rates) were effective against nymphs, with no differences between rates. Soil applications of cyantraniliprole, oxamyl, and imidacloprid were still toxic to adults and nymphs 7 and 14 d after treatment. Also, cyantraniliprole and tolfenpyrad were detrimental to psyllid reproduction. The incorporation of new chemistry in rotation programs may provide a useful management tool against this pest.

The Mexican rice borer, Eoreuma loftini (Dyar), is a major pest of sugarcane, Saccharum spp., rice, Oryza sativa L., and other graminaceous crops in Texas and Louisiana. The ability of conventional and electronic pheromone traps to monitor E. loftini in sugarcane and rice habitats was evaluated in two separate 2-yr field studies. Bucket traps baited with a synthetic female sex pheromone monitored E. loftini populations in commercial sugarcane fields in Calcasieu and Jefferson Davis Parishes throughout the 2014 and 2015 growing seasons. The number of E. loftini captured differed among months, but not between years or parishes. The percentage of E. loftini-injured stalks was greater in 2015 than in 2014, peaking in September of both years. Daily trap capture was correlated with the percentage of injured stalks. Injury from E. loftini in Louisiana sugarcane remained relatively low (<3% bored internodes) in both 2014 and 2015. In a second experiment, electronic traps were compared with conventional pheromone traps for monitoring E. loftini populations in sugarcane and rice habitats in Texas in 2013 and 2015. Performance of earlier electronic trap prototypes in 2013 was inconsistent and less effective than conventional traps. Improved trap design in 2015 resulted in more than threefold greater moth capture in electronic traps than in conventional pheromone traps. Electronic traps demonstrated potential to improve monitoring strategies for this pest and should be evaluated for lepidopterous pests in a variety of cropping systems.

Megacopta cribraria (F.), an invasive species introduced from Asia in 2009, is now prolific in the southeastern United States. Megacopta cribraria develops primarily on kudzu and soybean completing two generations. It is not well understood how this economic pest is affected by changes in geographic distribution in the United States or how population levels have changed since its establishment. The effect of insecticide application timing on field populations of M. cribraria is not well documented. These studies seek to understand how population dynamics of M. cribraria vary with geographic regions in Georgia. Effect of application timing on populations throughout the growing season was also examined. Weekly from 2012 to 2013, all life stages were enumerated from kudzu and soybean environments at several locations throughout Georgia from sweeps samples and flight intercept captures. Coordinates were recorded for locations, and classified as belonging to the Piedmont or Coastal Plain region of the state. Single spray trials were conducted from 2011–2014, and applications were made to soybean at intervals throughout the season. From 2012 to 2015, two kudzu patches near Griffin, GA, were monitored to detect population changes. Differences in population dynamics from locations around the state were found, but no clear effect of latitude, longitude, or region was observed. Insecticide applications applied in July suppressed nymph populations significantly better than treatments made earlier or later. Megacopta cribraria populations declined in 2014 and 2015 compared with 2012 and 2013. These studies provide the critical information for M. cribraria management in soybean in the southeastern United States.

Megacopta cribraria (F.), also known as the kudzu bug, is a soybean pest in the United States, and it can cause up to a 60% yield reduction if not controlled. Insecticides are commonly used to manage this pest in commercial soybean fields. However, other soybean production practices may also affect kudzu bug populations. This study investigated the effect of soil tillage, maturity group selection, and insecticide use on kudzu bug densities in soybean. During 2012 and 2013, at two locations each year in North Carolina, four varieties of soybean maturity groups were planted in June into conventionally tilled plots and into plots with cereal crop residue under reduced tillage conditions (mimicking double-crop production). Plots were further split as insecticide-protected and untreated. Four times more kudzu bugs were found in conventionally tilled than reduced till plots throughout the growing season. Selection of the maturity group influenced the attractiveness of the kudzu bug to oviposit on soybean. A 56% reduction of kudzu bug densities was achieved through insecticide treatment, with an ∼6% increase in yield. Information on how production practices, including soil tillage, affect kudzu bug populations in soybean may help growers select practices to minimize kudzu bug injury and protect yield.

At the time of this research, there were only two insecticides registered for control of cabbage maggot, Delia radicum L., in rutabaga in Canada, one of which (diazinon) will be deregistered by 2017, and resistance having been reported in some areas for the other (chlorpyrifos). To screen for chemistries to replace these organophosphates, and obtain efficacy data comparable between key vegetable brassica production areas in Canada, four small plot field studies were conducted concurrently in British Columbia, Saskatchewan, Ontario, and Quebec in 2009. These studies followed standardized protocols for seeding, application of insecticide drenches, sampling and damage assessment, and generally tested the same products. Of the insecticides evaluated, none provided maggot control comparable with the industry standard, chlorpyrifos. However, cyantraniliprole (Cyazypyr 200SC; registered in 2015 as Verimark) applied at 3 g AI (15.0 ml product)/100 m row of seeded rutabagas consistently provided the next highest reduction in % culls, suggesting the efficacy of this chemical may be improved if used at higher rates. The results of these studies are discussed in the context of current literature on D. radicum management in rutabaga. Future management strategies are also discussed, including a transplant plug treatment approach for increasing the dosage per plant and efficacy of chemistries such as Cyazypyr 200SC in the field.

Delia platura Meigen is an important pest in crops around the world. Its host range includes almost 50 species, and it can develop in soil organic matter. In Ecuador, D. platura is a serious problem for the crop, Lupinus mutabilis Sweet (Chocho), and it also attacks broccoli (Brassica oleracea L.). After broccoli is harvested, crop residue is mixed with soil or collected and stored close to Chocho fields. The objectives of this study were to determine the adaptive responses of larvae reared on different hosts and whether D. platura females are preferentially attracted to germinating L. mutabilis seeds or broccoli residue. Accordingly, larval performance and attraction of female D. platura reared on broccoli residue and L. mutabilis seeds were evaluated. The number of larvae, pupae, and adults were higher when reared on broccoli. Conversely, pupal weight was higher and time from larva to pupa, pupa to adult, and total life cycle were longer in flies reared on L. mutabilis. Although D. platura developed more quickly on broccoli, L. mutabilis was also a good host since pupae were heavier compared with flies reared on broccoli. Delia platura females reared on broccoli preferred broccoli residue to L. mutabilis in an olfactometer. Volatiles from broccoli residue in soil may attract D. platura females and stimulate oviposition on L. mutabilis seeds. Environmentally benign production of L. mutabilis crops with minimal insecticide applications may require the elimination of fresh broccoli residue as fertilizer in soils where L. mutabilis is cultivated.

The brown marmorated stink bug, Halyomorpha halys (Stål), is an invasive stink bug (Hemiptera: Pentatomidae) introduced into the United States in the mid-1990s. Since its initial establishment, it has spread throughout the east coast as far south as Georgia, and as far north as New Hampshire. While information is available regarding H. halys behavior and life history in some crops, relatively little information is available for vegetables such as peppers. Key questions include understanding when H. halys enters pepper fields to feed and how best to predict infestations, what population levels create economic damage, and if peppers that vary in capsaicin levels also vary in susceptibility to attack. To answer these questions, replicated plots were set up across four mid-Atlantic states using three types of peppers: sweet bell, sweet banana, and hot chili. We found that there was no difference in the overall abundance of all life stages of H. halys on all pepper varieties tested. However, there were differences in bug density by site, but these differences did not translate to differences in the proportion of damaged fruit. The presence of adult H. halys is a better predictor of damage in banana peppers, whereas nymphs are a better predictor in bell pepper. In addition, across all sites, the presence of egg masses was low in pepper crops and densities of both adults and immatures tend to peak on pepper plants in early August. Altogether, this information can be used to help develop a pest management program in peppers that will reduce crop losses to this new devastating pest, while reducing the reliance on insecticides to manage this pest at the same time.

The melon fly, Zeugodacus cucurbitae (Coquillett), is a serious pest of tropical horticulture, causing damage to cucurbits, tree fruits, and fruiting vegetables. Melon flies are especially attractive to freshly sliced cucumber, and this has led to the identification of a nine-compound kairomone lure that can be used to trap both female and male flies. In this study, a seven-compound lure, containing (Z)-6-nonenal, (Z)-6-nonen-1-ol, 1-octen-3-ol, (E,Z)-2,6nonadienal, (E)-2-nonenal, hexanal, and 1-hexanol, was formulated into PVC plugs (100 or 300 mg/plug) for field testing in wet traps. In Hawaii, 100 mg of the seven-compound cucumber lure, loaded in either plugs or glass capillaries, attracted more flies than traps containing Solulys protein over a 9-wk period. However, both cucumber lure formulations showed marked declines in the number of flies trapped after 3 wk. Similar results were obtained during a 6-wk field trial using 100 mg cucumber lure plugs in Taiwan. Increasing the cucumber lure loading rate to 300 mg/lure increased the effective trapping life of the attractant during a second 9-wk field trial conducted in Hawaii. The synthetic cucumber lure showed female-biased sex ratios in trap captures in the Taiwanese and second Hawaiian field trials. Protein lures captures were female-biased in all three field trials. Wet traps in Hawaii containing the cucumber lure were found to capture 25–30 nontarget insects/trap/week, less than half that captured with Solulys. Captured nontarget insects represented 37 families in 10 orders. The most common families caught were Ceratopogonidae (∼9 flies/trap) and Gryllidae (∼7 crickets/trap).

Female strawberry bud weevils (Anthonomus signatus Say) oviposit in developing flower buds of strawberries (Fragaria spp.), caneberries (Rubus spp.), and red bud (Cercis canadensis). After laying a single egg, weevils will girdle or “clip” the buds at the pedicel, killing the bud and preventing fruit development. This injury is of concern to commercial strawberry growers, who typically assume the loss of one clipped bud is the loss of one average sized fruit, causing the economic threshold to be set extremely low. There is evidence of compensation in some cultivars of strawberries, but research has previously only been conducted in perennial strawberry production. The majority of strawberries in the southeastern United States are grown in annual plasticulture systems. We assessed the ability of five strawberry cultivars commonly grown in annual plasticulture to compensate for A. signatus injury by removing buds at different growth stages. There was no effect of bud removal on total yield in any of the cultivars tested. Harvest timing was affected by simulated A. signatus damage in some cultivars, which may be an important consideration for direct market strawberry growers.

The influences of ootheca age and temperature on the life history of Aprostocetus hagenowii (Ratzeburg) (Hymenoptera: Eulophidae), a gregarious ootheca parasitoid of the American cockroach Periplaneta americana (L.) (Dictyoptera: Blattidae), were evaluated. Oothecae were incubated at 20, 25, and 30 °C to produce oothecae aged 1–60, 1–40, and 1–30 d old, respectively. Fitness traits (development time, percentage emergence, number of progeny, percentage female progeny, and female body size) of A. hagenowii developing in these different-aged oothecae were determined. For oothecae incubated at 20, 25, and 30 °C, parasitoids successfully developed in oothecae aged up to 50, 30, and 20 d old, which represent 72.9%, 65.9%, and 61.9% of the total embryonic development time of P. americana, respectively, without any changes in their fitness traits. When A. hagenowii from oothecae kept at constant temperatures (20, 25, 30, 32, and 35 °C) were compared, the immature development time (71.0–34.0 d) and adult life span decreased with increasing temperature. No parasitoid emerged at 35 °C. The lower, upper, and optimal temperature-dependent developmental thresholds were 9.5, 34.2, and 31.1 °C, respectively. Thermal constant for total immature development was 666.7 degree-days. Temperature did not affect lifetime realized fecundity and number of oothecae parasitized by females but did influence parasitism activities over time. Sugar-fed females sustained longer periods of high parasitism rates (≥70%) at 20–30 °C (15–30 d) than at 32–35 °C (1–5 d). These results are useful for determining the ootheca age and temperature range optimal for parasitoid rearing and for estimating the effectiveness of biological control by the wasps.

Resistance evolution by target pests threatens the sustainability of Bt maize in Africa where insect resistance management (IRM) strategies are faced by unique challenges. The assumptions, on which current IRM strategies for stem borers are based, are not all valid for African maize stem borer species. The high dose–refuge strategy which is used to delay resistance evolution relies heavily on the presence of appropriate refuges (non-Bt plants) where pests are not under selection pressure and where sufficient numbers of Bt-susceptible individuals are produced to mate with possible survivors on the Bt maize crop. Misidentification of stem borer species and inaccurate reporting on wild host plant diversity over the past six decades created the perception that grasses will contribute to IRM strategies for these pests in Africa. Desired characteristics of refuge plants are that they should be good pest hosts, implying that larval survival is high and that it produces sufficient numbers of high-quality moths. Refuge plants should also have large cover abundance in areas where Bt maize is planted. While wild host plants may suffice in IRM strategies for polyphagous pests, this is not the case with stenophagous pests. This review discusses data of ecological studies and stem borer surveys conducted over the past decade and shows that wild host plants are unsuitable for development and survival of sufficient numbers of stem borer individuals. These grasses rather act as dead-end-trap plants and do not comply with refuge requirements of producing 500 susceptible individuals for every one resistant individual that survives on Bt maize.

To better understand the application prospect of cyantraniliprole against the Asian corn borer, Ostrinia furnacalis, a diet-incorporation bioassay was adopted to determine the toxicity of cyantraniliprole against the fourth instar of O. furnacalis. Moreover, other experiments were conducted to examine effects of sublethal levels of cyantraniliprole on larval development, nutrient utilization, and reproduction. In this study, cyantraniliprole showed a high toxicity to fourth-instar larvae of O. furnacalis at dosages of 0.05 µg/g (LC₅), 0.11 µg/g (LC₂₀), 0.20 µg/g (LC₄₀), and 0.26 µg/g (LC₅₀) administered through artificial diet. At three sublethal dosages, cyantraniliprole inhibited larval feeding processes, decreased the relative growth rate, the relative consumption rate, the efficiency of food ingestion, and the efficiency of food digestion, as well as decreased the contents of nutrients such as proteins, lipids, and carbohydrates. All these effects go against to the normal growth of O. furnacalis, including reductions in larval and pupal weight, the extension of the larval and pupal period, the prolongation of the adult preoviposition period, total preoviposition period, and mean generation time, and the reduction of adult longevity, oviposition period, and eggs laid by female adults. Together, these changes resulted in the reduction of the intrinsic rate of increase. Hence, even at sublethal concentrations, cyantraniliprole can affect population dynamics by reducing the survival rate, fecundity, and population parameters. This result provides useful information for developing control strategies for O. furnacalis.

A dengue fever outbreak in Guangzhou, Guangdong Province, China, in 2014 resulted in ∼37,000 cases and five deaths. Insecticides were sprayed to control the vector of this outbreak, Aedes albopictus (Skuse), a species of mosquito. Aedes albopictus specimens collected from Huadu District (HD), Huangpu District (HP), Luogang District (LG), and Nansha District (NS) in Guangzhou were evaluated using WHO-recommended bioassays for both larvae and adult mosquitoes to determine population resistance to deltamethrin, beta-cypermethrin, cypermethrin, permethrin, dichlorvos, temephos, propoxur, and DDT. Compared with a susceptible laboratory strain of Ae. albopictus (S-lab), all populations showed decreased sensitivities to the eight insecticides, with resistance ratios (RRs) ranging from 2.2 to 275. The RRs were 6.8–275 for pyrethroids, 2.2–4.4 for organophosphates, 5.7–9.0 for carbamates, and 5.3–94.3 for organochlorines. For adult mosquitoes, all populations were sensitive to dichlorvos with 100% mortalities. Mosquitoes from HP, LG, and NS were also sensitive to propoxur. But for other tested insecticides, different degrees of resistance (mortality rate ranging from 11.7% to 94.7%) were observed. Among the four field populations, the resistance levels are presented as follows in descending order: HP > HD > NS > LG. The levels among insecticides classes were pyrethroids > organochlorines > carbamates > organophosphates.

Sand flies (Diptera: Psychodidae, subfamily Phlebotominae) are hematophagous insects that are known to transmit several anthroponotic and zoonotic diseases. Reliable identification of sand flies at species level is crucial for their surveillance, the detection and spread of their pathogens, and the implementation of targeted pest control strategies. Here, we designed a novel, time-saving, cost-effective and easy-to-apply molecular methodology, which avoids sequencing, for the identification of the following six Eastern Mediterranean sand fly species: Phebotomus perfiliewi Parrot, Phebotomus simici Theodor, Phebotomus tobbi Adler and Theodor, Phebotomus papatasi Scopoli, Sergentomyia dentata Sinton, and Sergentomyia minuta Theodor. This methodology, which is a multiplex PCR assay using one common and six diagnostic primers, is based on species-specific single-nucleotide polymorphisms of the nuclear 18S rRNA gene. Amplification products were easily and reliably separated in agarose gel yielding one single clear band of diagnostic size for each species. Further, we verified its successful application on tissue samples that were immersed directly to the PCR mix, skipping DNA extraction. The direct multiplex PCR can be completed in < 3 h, including all operating procedures, and costing no more than a simple PCR. The applicability of this methodology in the detection of hybrids is an additional considerable benefit.

Spodoptera exigua (Hübner) is one of the polyphagous pests destroying crops such as sugar beet worldwide. The aim of this experiment was to evaluate the resistance of 24 sugar beet genotypes to S. exigua. In this study, nine sugar beet cultivars (Dorotea, Tous, Persia, Silenta, Jaam, HM1339RZ, Jolgeh, Ekbatan, and SBSI006), three hybrids ((7112*SB36)*Sh-1-HSF-5, (7112*SB36)*Sh-1-HSF-15, and (7112*SB36)*Sh-1-HSF-16), four lines (FC201, FC301, FC220, and FC221), and eight populations (SB26, SB27, SB28, SB29, SB30, SB33, SB34, and SB35) were assessed. The experiments were performed under laboratory conditions at 25 ± 1 °C, 60 ± 5% RH, and a photoperiod of 16:8 (L:D) h using age-stage, two-sex life table procedure. The larval period ranged from 17.09 d on FC301 to 14.47 d on SB30. The total fecundity (F) was highest on (7112*SB36)*Sh-1-HSF-5 (905.13 eggs) and lowest on FC301 (312.46 eggs). (7112*SB36)*Sh-1-HSF-5 and FC220 with 318.02 and 26.76 eggs per individual had the highest and lowest net reproductive rates (R₀), respectively. The highest values of the intrinsic rate of increase (r) and finite rate of increase (λ) were on (7112*SB36)*Sh-1-HSF-5 (r: 0.187 d ^{– 1}, λ: 1.205 d ^{– 1}) and the lowest were on FC301 (r: 0.104 d ^{– 1}, λ: 1.11 d ^{– 1}). SB26 (r: 0.185 d ^{– 1}, λ: 1.203 d ^{– 1}) and FC220 (r: 0.114 d ^{– 1}, λ: 1.12 d ^{– 1}) had no significant difference with (7112*SB36)*Sh-1-HSF-5 and FC301, respectively. The comparison of demographic parameters of S. exigua on 24 sugar beet genotypes suggested that FC220 and FC301 were the most resistant and (7112*SB36)*Sh-1-HSF-5 and SB26 were the most susceptible genotypes to this pest.

The sugarcane aphid, Melanaphis sacchari (Zehntner), has established itself as a perennial pest of grain and forage sorghums in the United States since the summer of 2013. We conducted traditional plant resistance studies that determine tolerance, antibiosis, and antixenosis in 32 sorghum genotypes when challenged with sugarcane aphids. The genotypes included one exotic plant introduction and 31 seed and pollinator parental lines that are used to produce grain, sudangrass, and forage sorghum hybrids. One seed parent (B11055) and one grain pollinator parent (R13219) expressed significant degrees of tolerance, antibiosis, and antixenosis and were top performers in all three resistance type experiments. An additional group of seed parents (B13045 and B1057) and grain pollinator parents (R11159, R13422, and RTx2908) and the plant introduction (PI 550610) resulted in an intermediate range of phenotypic resistance (i.e., 4.0 < 6.0) indicative of antibiosis from reduced fecundity, increased intrinsic rate of increase, and increased generation times. The forms of resistance expressed in these lines, especially B11055 and R13219, have great potential in breeding programs that can be integrated into useable forms of resistant sorghums.

Biology and physiological traits of Sitotroga cerealella Olivier, a world-wide insect pest of cereals, were investigated on different grains (barley, maize, rye, sorghum, triticale, and wheat). Larval and pupal duration was the shortest on wheat and triticale, and the longest on sorghum. There were significant differences in survival rate of immature stages on grains with different seed hardness. The highest realized fecundity and egg fertility was observed on triticale and the lowest was seen on sorghum. Larvae fed on triticale and wheat showed higher amount of α-amylase activity than larvae fed on other grains. Maximum V_max/K_M ratio was determined for the midgut α-amylase of S. cerealella larvae fed on wheat. Whole-body protein, lipid, and glycogen contents of pupae reared on sorghum and rye were significantly lower than those reared on other grains. The statistical analysis showed that the clear correlation could be drawn between the biological characteristics and energy contents of S. cerealella on one side and seed hardness, amylolytic activity, and food consumed on the other. According to the findings of this study, the variable responses of S. cerealella to feeding on different host grains could be attributed to the quality of diets tested.

Athetis dissimilis (Hampson) has emerged as a serious pest on corn in recent years in China. Understanding the population response of A. dissimilis to temperature will be beneficial for adopting control strategies for this pest. The impact of five constant temperatures (17, 21, 25, 29, and 33 °C) on the life table of A. dissimilis was studied using age-stage, two-sex life table method in the laboratory. The results showed that the developmental time of egg, larva, pupa, and adult decreased when temperature increased from 17 °C to 33 °C. The TPOP (total preoviposition period) decreased with temperature increasing from 17 °C to 29 °C, while the longest APOP (adult preoviposition period) occurred at 21 °C (3.57 d) and the shortest at 33 °C (2.15 d). The fecundity increased from 407.52 to 763.94 eggs as temperatures were raised from 17 to 25 °C, but decreased at temperatures from 25 °C to 33 °C. The intrinsic rate of increase (r), finite rate of increase (λ), and net reproductive rate (R₀) increased as temperatures increased from 17 to 25 °C, then decreased when temperatures exceeded 25 °C. In contrast, the mean generation time (T) decreased as temperatures increased from 17 to 33 °C. Based on the estimated data, the highest female age-stage-specific fecundity (f_x) and age-specific fecundity (m_x) were 81.91 and 45.04 eggs, respectively, at 25 °C. The age-stage life expectancy (e_xj) of all stages decreased as the temperature increased. The reproductive value (v_xj) increased gradually with age and stage. The developmental rates of A. dissimilis between 17 to 29 °C fit the linear equation y = –0.01315 + 0.001303x, with a coefficient of determination (R²) of 0.9314. In conclusion, our finding clearly states that A. dissimilis has the greatest population increase at 25 °C, and this may help develop appropriate pest management strategies.

One method of control of house flies, Musca domestica L. (Diptera: Muscidae), and other filth flies is by repeated release of large numbers of pupal parasitoids such as Spalangia endius Walker. Rearing these parasitoids may be facilitated by understanding how host factors affect their production. Previous studies have examined the effects of host size and host age on parasitoid production, but have not examined the interaction between host size and host age or the effects with older females, which may be less capable of drilling tough hosts. Females were given hosts of a single size–age category (small young, small old, large young, or large old) for 2 wk. The effect of host size and of host age on parasitoid production depended on female age. On their first day of oviposition, females produced more offspring from large than from small hosts, but host age had no significant effect. The cumulative number of parasitoids produced in the first week was not significantly affected by host size or host age. However, the cumulative number of parasitoids produced over 2 wk was affected by both host size and host age, with the greatest number of parasitoids produced from small young hosts. Thus, not only are smaller hosts cheaper to produce, but these results suggest that their use may have no effect or a positive effect on the number of parasitoids that can be produced when females are ovipositing for a week or two.

Poultry barns provide an ideal breeding environment for Musca domestica L. (Diptera: Muscidae) owing to the controlled temperatures and litter (manure plus bedding material) accumulation. Management techniques that render the litter less suitable for immature stage development, such as the addition of naturally occurring insecticidal substances, could reduce fly infestations. The effectiveness of acetic, boric, and citric acids; diatomaceous earth; and hydrated lime at restricting female landing and growth of house flies in duck litter was evaluated. Litter treated with 1.9% and 4.7% by weight of acetic or boric acid had significantly lower adult emergence rates compared with the same concentrations of citric acid, diatomaceous earth, hydrated lime, or the untreated control litter. The pH of duck litter treated with acetic or citric acid was significantly reduced and remained significantly lower than the control litter (pH 8.7) for 10 d. Significantly more house flies landed on a house fly-rearing substrate (wheat bran, powdered milk, bloodmeal, water, and yeast) than litter treated with any of the other test substances or the control. The LC₅₀ for boric acid was estimated to be 0.01% by weight, which was lower than that of acetic acid (1.42%). Similarly, the LC₉₀ of boric acid was estimated to be 0.12%, which was lower than that of acetic acid (10.03%). Acetic acid and boric acid have the potential to be incorporated into litter as a pest management tactic to reduce house fly populations in duck production facilities.

Yeasts, often in hydrolyzed form, are key ingredients in the larval and adult diets of tephritid fruit fly colonies. However, very little is known about the presence or role of yeasts in the diets of tephritid fruit flies in nature. Previous studies have identified bacteria but not detected yeasts in the gut of Queensland fruit fly, Bactrocera tryoni (Froggatt), one of Australia's most economically damaging insect pests of horticultural crops and of significant biosecurity concern domestically and internationally. Here we demonstrate that cultivable yeasts are commonly found in the gut of B. tryoni larvae from fruit hosts. Analysis of the ITS1, 5.8S rRNA gene, and ITS2 sequences of randomly selected isolates identified yeasts and yeast-like fungi of the genera Aureobasidium, Candida, Cryptococcus, Hanseniaspora, Pichia, and Starmerella. The prevalence of these yeasts in fruits suggests that larvae consume the yeasts as part of their diet. This work highlights that yeasts should be considered in future tephritid larval gut microbiota studies. Understanding tephritid–microbial symbiont interactions will lead to improvements in artificial diets and the quality of mass-reared tephritids for the sterile insect technique.