To recommend new pest management tactics and strategies to farmers and policy makers, economic entomologists must evaluate the economics of biologically reasonable approaches. We collected data to determine how frequently these economic evaluations occur. We discovered from our survey of entomological journals representing the discipline of economic entomology that <1% of research papers published since 1972 include economic evaluations of pest management tactics. At least 85% of these analyses were performed by entomologists and not economists. Much of the research on economic evaluations is performed without special funds granted by agencies separate from the authors' institutions. In the United States, USDA competitive grants supported 20% of the economic evaluations published since 2000. However, only ≈12% of the projects funded since 2000 by three sections of the USDA (Crops at Risk, Risk Avoidance and Mitigation Program, and Pest Management Alternatives Program) resulted in publications concerning economic evaluations. If the purpose of economic entomology is to ultimately determine the value of different kinds of tactics, the discipline may need to take steps to enhance the research that supports these evaluations.

The mealybug species Planococcus citri (Risso) and Planococcus minor (Maskell) (Hemiptera: Coccoidea: Pseudococcidae) have special significance to U.S. quarantine and U.S. agriculture. Commonly intercepted at U.S. ports-of-entry, they are difficult to identify based on morphological characters. This study presents a molecular method for distinguishing P. citri, P. minor, and a genetically distinct group that is morphologically identical to P. citri, from Hawaii. This method uses polymerase chain reaction (PCR) followed by restriction fragment polymorphism analysis (RFLP) using the restriction enzymes BspHl, BsmHl, and HpHl. The resulting band patterns can be visualized in a 2% agarose gel and are sufficient to differentiate between the three entities mentioned above. PCR-RFLP diagnostics can be used for all life stages and is cheaper and faster than DNA sequencing.

To compare resistance to small hive beetles (Coleoptera: Nitidulidae) between Russian and commercial Italian honey bees (Hymenoptera: Apidae), the numbers of invading beetles, their population levels through time and small hive beetle reproduction inside the colonies were monitored. We found that the genotype of queens introduced into nucleus colonies had no immediate effect on small hive beetle invasion. However, the influence of honey bee stock on small hive beetle invasion was pronounced once test bees populated the hives. In colonies deliberately freed from small hive beetle during each observation period, the average number of invading beetles was higher in the Italian colonies (29 ± 5 beetles) than in the Russian honey bee colonies (16 ± 3 beetles). A similar trend was observed in colonies that were allowed to be freely colonized by beetles throughout the experimental period (Italian, 11.46 ± 1.35; Russian, 5.21 ± 0.66 beetles). A linear regression analysis showed no relationships between the number of beetles in the colonies and adult bee population (r² = 0.1034, P = 0.297), brood produced (r² = 0.1488, P = 0.132), or amount of pollen (r² = 0.1036, P = 0.295). There were more Italian colonies that supported small hive beetle reproduction than Russian colonies. Regardless of stock, the use of entrance reducers had a significant effect on the average number of small hive beetle (with reducer, 16 ± 3; without reducer, 27 ± 5 beetles). However, there was no effect on bee population (with reducer, 13.20 ± 0.71; without reducer, 14.60 ± 0.70 frames) or brood production (with reducer, 6.12 ± 0.30; without reducer, 6.44 ± 0.34 frames). Overall, Russian honey bees were more resistant to small hive beetle than Italian honey bees as indicated by fewer invading beetles, lower small hive beetle population through time, and lesser reproduction.

Three almond field trials were conducted during 2003 and 2004 at two locations in central (Fresno County) and northern (Yolo County) California to evaluate the potential effects of commercial applications of Captan on honey bees, Apis mellifera L. Captan was applied at 5.0 kg (AI)/ha during bloom. Hives were evaluated for hive health and brood development parameters for ∼2 mo after application. This study showed that the application of Captan was not harmful to foraging honey bees or their brood. No treatment-related effects were noted on hive weights, dead bee deformity, number of dead bees, survival of individual larvae, weight of individual emerging adults, and other hive health parameters.

Tomato spotted wilt virus (family Bunyaviridae, genus Tospovirus, TSWV) causes annual economic losses in pepper, Capsicum annuum L., across the southern United States and is transmitted by several species of thrips, including the tobacco thrips, Frankliniella fusca (Hinds). Reduced virus transmission and symptom severity as plant age increases is known as mature-plant resistance. TSWV transmission to pepper plants was examined in three and four age classes in field and greenhouse trials, respectively. In the field trial, ‘Camelot’ bell pepper plants were exposed to potentially viruliferous F. fusca 37, 51, or 65 d postsowing. Two greenhouse trials of Camelot bell and one trial each of ‘Bounty’ and ‘Pageant’ banana pepper plants were exposed to potentially viruliferous F. fusca, 43, 57, 71, or 85; 48, 62, 75, or 90; 42, 56, 70, or 84; and 43, 57, 71, or 85 d postsowing, respectively. Linear and hyperbolic regressions of percentage of infected plants per block on days postsowing indicated mature-plant resistance in all trials. All models were significant, but hyperbolic curves better fit the data than linear models. Hyperbolic models were used to calculate the number of days posttransplant at which a 50% decrease from the predicted percentage of infected plants at transplant age (42 d postsowing) was expected. This was referred to as days posttransplant-50 (DPT₅₀). DPT₅₀ occurred within 9 days posttransplant age for all trials, indicating that early TSWV management in pepper is critical.

The southern green stink bug, Nezara viridula (L.), is a significant pest of cotton, Gossypium hirsutum L., and is becoming an increasing challenge due to the decrease in use of broad-spectrum insecticides on the crop. The southern green stink bug can vector an opportunistic Pantoea agglomerans strain (designated Sc 1-R) into cotton bolls, resulting in infection. The appearance of stink bug damage varies, and pest managers cannot readily identify its source. This research reports a systematic depiction of green, immature boll responses at various stages of maturity (1, 2, and 3 wk post-anthesis [WPA]) to stink bug injury and to infection by the vectored cotton pathogen by demonstrating the progression of effects 1, 2, and 3 wk after exposure (WAE). When laboratory-reared adult southern green stink bug not harboring Sc 1-R deposited bacteria into greenhouse-grown bolls at 1, 2, or 3 WPA during feeding/probing, bacteria reached concentrations of 10⁹, 10⁹, and 10³ colony-forming units (CFUs)/g tissue, respectively, at 3 WAE, yet caused minimal seed and lint damage regardless of the age of the bolls that were penetrated. Bolls at a maturity of 1 or 2 WPA showed similar susceptibility when exposed to stink bugs that vectored Sc 1-R. After a week of infection, seeds were salmon-pink with normal white lint and up to 10⁴ CFUs/g tissue when Sc 1-R was detected. Necrosis of the entire inoculated locule(s) with a maximum Sc 1-R concentration detected at 10⁸ CFUs/g tissue occurred in samples harvested 2 or 3 WAE. Conversely, seed and lint deterioration due to the transmitted opportunist into bolls exposed 3 WPA was confined to the puncture site. In summary, after a week of development, bolls were tolerant to southern green stink bug feeding/ probing damage and to nonpathogenic bacteria, but they were severely damaged when the opportunistic pathogen Sc 1-R was transmitted. At 3 WPA, the fruit was immune to the spread of the pathogen with infections confined to the puncture site.

Codling moth, Cydia pomonella (L.) (Lepidoptera: Tortricidae), a serious pest of pome fruit, is a threat to exportation of apples (Malus spp.) because of the possibility of shipping infested fruit. The need for alternatives to fumigants such as methyl bromide for quarantine security of exported fruit has encouraged the development of effective fumigants with reduced side effects. The endophytic fungus Muscodor albus Worapong, Strobel and Hess (Ascomycota: Xylariales) produces volatile compounds that are biocidal for several pest organisms, including plant pathogens and insect pests. The objectives of our research were to determine the effects of M. albus volatile organic compounds (VOCs) on codling moth adults, neonate larvae, larvae in infested apples, and diapausing cocooned larvae in simulated storage conditions. Fumigation of adult codling moth with VOCs produced by M. albus for 3 d and incubating in fresh air for 24 h at 25°C resulted in 81% corrected mortality. Four- and 5-d exposures resulted in higher mortality (84 and 100%, respectively), but control mortality was also high due to the short life span of the moths. Exposure of neonate larvae to VOCs for 3 d on apples and incubating for 7 d resulted in 86% corrected mortality. Treated larvae were predominantly first instars, whereas 85% of control larvae developed to second and third instars. Exposure of apples that had been infested for 5 d, fumigated with M. albus VOCs for 3 d, and incubated as described above resulted in 71% corrected larval mortality. Exposure of diapausing cocooned codling moth larvae to VOCs for 7 or 14 d resulted in 31 and 100% mortality, respectively, with negligible control mortality. Our data on treatment of several stages of codling moth with M. albus VOCs indicate that the fungus could provide an alternative to broad spectrum chemical fumigants for codling moth control in storage and contribute to the systems approach to achieve quarantine security of exported apples.

Advances in the genetic modification of organisms are creating new opportunities for the control of insect pests of both agriculture and public health significance. The timing and sex specificity of lethal transgene activation can be tailored to enhance the pest population control efficiency of mass-released, genetically modified insects. We developed mathematical models to determine the optimal timing and sex specificity of lethal transgene activation for the control of different types of pest population. We show that optimal release strategies are not only sensitive to the parameters governing growth of the population but also can be drastically affected by the inclusion of insect stage structuring, competition, and space. We emphasize the necessity of including these additional levels of complexity in future theoretical assessments as they are likely important considerations for designing transgenic organisms as well as their application in genetic control.

A Bacillus thuringiensis (Bt)-based formulation intended to increase feeding response in Spodoptera exigua (Hübner) (Lepidoptera: Noctuidae) was developed. Eight matrices were prepared from natural ingredients and confronted with fresh maize leaves to select one highly palatable to larvae. The selected matrix was combined with Bt HD-125 strain at three different concentrations (30, 70, and 100 g/kg) of the spore-crystal complex to elaborate three insecticidal formulations. Effects caused by the matrix, including palatability, any adverse effect, and reduction in toxic activity of the strain, were tested on the formulations. Results indicated that the blend of modified cornstarch, porcine gelatin, and dried corncob was the most preferred by larvae. Formulations obtained were evaluated in mortality bioassays with neonate larvae in laboratory, using artificial diet, and in the greenhouse, with maize, Zea mays L., plants to compare their effectiveness when applied to natural food. In laboratory tests, all formulations, including a commercial formulation, were ingested by larvae causing high mortality in neonate larvae; in the greenhouse tests, formulations were also ingested causing mortality in larvae, overcoming commercial formulation effectiveness. Results suggest that the selected matrix combined with Bt 70 g/kg is the most suitable formulation to achieve effective control because this concentration acts faster than the lower concentration and is equal than the higher concentration. This formulation, designed specifically against a particular pest, is highly effective and offers a high potential for effective pest control.

The European corn borer, Ostrinia nubilalis (Hübner) (Lepidoptera: Crambidae), is a quarantine pest for several fresh commodities, including corn-on-the-cob, bell peppers, and green beans. Methyl bromide fumigation is the usual phytosanitary treatment, but the fumigant is under increasing regulation as a stratospheric ozone-depleting substance. Ionizing radiation is a relatively new commercial alternative that is currently used in several countries. The present research explored radiation doses that would provide quarantine security for commodities at risk of being infested by O. nubilalis. Radiotolerance of late pupae (the most tolerant stage infesting commodities) as determined by hatch of F₁ eggs was not affected by host (meridic diet versus ear corn) or temperature (1 versus 13°C) but was positively affected by low oxygen. Longevity was shorter for adults of irradiated than nonirradiated pupae. The minimum absorbed dose for phytosanitary irradiation against O. nubilalis could vary from 233 Gy for prevention of F₁ pupation to 343 Gy for prevention of F₁ egg hatch. Lower doses might be possible if greater risk of treatment failure was acceptable.

Insects are commonly found by Hawaii's quarantine inspectors on Christmas trees imported from the Pacific Northwest. To reduce the risk of importing yellowjacket (Vespula spp.) queens and other insects, an inspection and tree shaking certification program was begun in 1990. From 1993 to 2006, the annual percentage of shipped containers rated by Hawaii quarantine inspectors as moderately or highly infested with insects was significantly higher for manually shaken trees than for mechanically shaken trees. Between 1993 and 2001, 343 insect species in total were recovered from Christmas trees. Live western yellowjacket [Vespula pensylanica (Saussure) ] queens were intercepted both from containers certified as manually shaken and from containers certified as mechanically shaken. The standard manual shaking protocol removed about one-half of the queens from Douglas fir [Pseudotsuga menziesii (Mirb.) Franco] trees that were naturally infested with western yellowjacket queens. We investigated the use of preharvest sprays of permethrin as a complement to shaking procedures used to control yellowjackets and other insects. Western yellowjacket queens and honey bees (surrogates for wasp pests) were exposed to Noble fir foliage that had been sprayed in the field with permethrin >6 wk before harvest. Pesticide residues provided complete control (moribundity or mortality) in both species. The sprays did not affect needle retention or quality of Noble fir foliage. We conclude that preharvest sprays of pyrethroid insecticides could be used in combination with mechanical shaking to greatly reduce the quarantine risk of yellowjacket queens and other insects in exported Christmas trees.

Several longhorn beetles (Cerambycidae) and bark beetles (Scolytinae) have been accidentally introduced to New Zealand and are now widespread and abundant. In particular Arhopalus ferus (Mulsant) represents a significant quarantine risk for export timber. Because of this risk timber is fumigated with methyl bromide. Six different light traps baited with different colors (yellow, red, green, white, UV-black light [UV-BL], and UV-black-light-blue [UV-BLB]) were investigated for their population monitoring potential and as a push-pull (incorporating mass trapping) alternative control technique. UV-BLB light traps captured an order of magnitude more A. ferus (122 individuals per night) than yellow light traps (eight individuals per night). The bark beetles Hylurgus ligniperda (F.) and Hylastes ater (Paykull) were most attracted to UV-BL lights that captured 2–4 times more beetles than traps baited with other wavelengths. Results suggest that light traps provide a sensitive method for population monitoring. The responses of these wood borers and bark beetles to different colored light traps provide an opportunity to apply a push-pull control technique. The management of these species could be improved by minimizing the visual attractiveness (push) of wood processing facilities through a conversion to low intensity yellow site lighting, combined with the strategic placement of UV light traps for mass-trapping of residual populations (pull). Light management on its own is unlikely to eliminate the quarantine risk entirely; however, it is likely to reduce populations substantially and contribute toward the aim of reducing methyl bromide use.

Field-cage experiments were performed to determine the effectiveness of MultiLure traps (Better World MFG Inc., Fresno, CA) baited with NuLure (Miller Chemical and Fertilizer Corp., Hanover, PA) or BioLure (Suterra LLC, Inc., Bend, OR) in capturing individually marked Mexican fruit fly, Anastrepha ludens (Loew), and West Indian fruit fly, Anastrepha obliqua (Macquart) (Diptera: Tephritidae), of both sexes. Experimental treatments involved wild and laboratory-reared flies of varying ages (2–4 and 15–18 d) and dietary histories (sugar only, open fruit, open fruit plus chicken feces, and hydrolyzed protein mixed with sugar). Data were divided into two parts: total captures over a 24-h period and trap visits/landings, entrances into interior of trap ,and effective captures (i.e., drowning in liquid bait or water) over a 5-h detailed observation period (0600–1100 hours). The response to the two baits varied by fly species, gender, physiological state, age, and strain. Importantly, there were several highly significant interactions among these factors, underlining the complex nature of the response. The two baits differed in attractiveness for A. obliqua but not A. ludens. The effect of strain (wild versus laboratory flies) was significant for A. ludens but not A. obliqua. For effect of dietary history, adults of both species, irrespective of sex, were significantly less responsive to both baits when fed on a mixture of protein and sugar when compared with adults fed the other diets. Finally, we confirmed previous observations indicating that McPhail-type traps are quite inefficient. Considering the total 24-h fly tenure in the cage, and independent of bait treatment and fly type (i.e., strain, adult diet, gender and age), of a total of 2,880 A. obliqua and 2,880 A. ludens adults released into the field cages over the entire study (15 replicates), only 564 (19.6%) and 174 (6%) individuals, respectively, were effectively caught. When only considering the 5-h detailed observation period and independent of bait treatment and fly type, of a total of 785 marked flies that landed on traps (519 females and 266 males, respectively), only 10.3% (144 females and 59 males) and 20.8% (25 females and 18 males) A. obliqua and A. ludens individuals, respectively, ended up being effectively captured. We discuss the practical implications of these findings with respect to developing new baits and designing new traps and to the interpretation of capture results in the field.

The seasonal migration of the Helicoverpa armigera (Hübner) (Lepidoptera: Noctuidae) over the Bohai Sea was observed with a searchlight trap and an entomological radar located on a small island in the center of the sea, and through a network of light-traps around the Bohai region. The H. armigera moths were observed to migrate over the sea at least as early as May and light trapping through a network suggested migration might start as early as April, as soon as the moths had emerged from overwintering pupae. H. armigera moths migrated toward the north in southerly winds during spring and summer, and returned south on nights with northerly winds, or at altitudes where the wind was northerly, during fall. The passage of a weather front (cold or warm) or trough at ≈1700 hours provokes migration of H. armigera over the sea. The H. armigera generally flew at altitudes of below 1,500 m above sea level (asl) with layer concentrations at 200–500 m asl, where the wind direction, wind speed, and temperature were optimum. During fall migration, H. armigera tended to orient toward the southwest and was able to compensate for the wind drift by turning clockwise when the downwind direction was<225° but counterclockwise when it was>225°. The displacement speed measured with the radar was 24–41 km/h, the duration of flight was 8–11 h and the maximum migration rate was 1,894 moths per km per h.

Butterfly species used for live exhibition differ in life span, encounter rate, behavior, and cost. By knowing which species are more cost-effective, exhibitors can customize their butterfly imports and purchase butterfly species that provide the best return on their investment. We used mark-recapture techniques to estimate mean life span and encounter rates for 39 butterfly species commonly purchased by exhibitors. In addition, the behavior of 29 species was quantified and characterized as suitable versus unsuitable by direct observation. The data were combined to calculate 1) the total number of days of suitable performance to be expected from a species, and 2) the cost per individual per day based on the number of expected suitable days. The most cost-effective butterfly relative to others in this study was Heliconius hecale F. (total suitable days, 33.4; cost per day, $0.05); the least cost-effective species was Doleschallia bisaltide Cramer (total suitable days, 0.1; cost per day, $13.15). By using this protocol, exhibitors can selectively incorporate more cost-effective species, save money on imports, and improve the visual appeal of their live exhibits.

Contarinia nasturtii (Kieffer) (Diptera: Cecidomyiidae), a common insect pest in Europe and a new invasive pest in North America, causes severe damage to cruciferous crops. In the United States, C. nasturtii was first reported in western New York in 2004. From 2005 to 2007, field surveys were conducted in western New York to investigate the occurrence of C. nasturtii in weeds that might serve as a reservoir for this pest. The results indicate that 12 cruciferous weed species were found in and around commercial vegetable crucifer plantings, and C. nasturtii emergence was detected from most of them. The number of C. nasturtii that emerged from the weeds was low and varied by species, year, and the timing of sampling. Peak emergence from weeds in fallow fields occurred in June. Nonchoice tests in the laboratory showed that significantly fewer larvae were found on cruciferous weeds than on cauliflower plants, although C. nasturtii could lay eggs on the weeds. When weeds and cauliflower plants were simultaneously exposed to C. nasturtii adults for egg laying (choice tests), 97.3% of the C. nasturtii larvae were found on the cauliflower plants 8 d after oviposition, 2.7% on Sinapis arvensis L., and none on the other five weed species tested. Our results suggest that cruciferous weeds can serve as alternative host plants of C. nasturtii but are less suitable than cauliflower. A method of detecting C. nasturtii on weeds and control of C. nasturtii through weed management are discussed.

Termite soldiers produce a vibratory alarm signal to warn conspecific workers. This study recorded and characterized the alarm signals of Coptotermes acinaciformis (Froggatt) (Isoptera: Rhinotermitidae) and then investigated the effect of playing these recorded alarm signals on C. acinaciformis feeding activity. Foraging groups of termites were offered paired wooden blocks: either one block, continuously stimulated with a vibratory alarm signal, paired with a nonstimulated block (the alarm treatment), continuously stimulated with a pink noise signal, paired with a nonstimulated block (control for nonspecific vibrations) or two nonstimulated blocks (control for environmental effects), for 4 wk. The amount of wood eaten in the blocks stimulated by the alarm signals was significantly less than the paired nonstimulated blocks, while there seemed to be no preference in the case of the pink noise playback or control for direction. Importantly, the termites seemed not to have adapted to the recorded alarm signal over the 4-wk duration of the experiment, unlike previous studies using nonbiologically derived signals.

Visual and olfactory cues were shown to mediate short-distance orientation to different colors in the presence and in the absence of food in Melittia oedipus Oberthür (Lepidoptera Sesiidae), a biological control agent of Coccinia grandis (L.) Voigt (Violales: Cucurbitaceae). Yellow was the color most preferred by M. oedipus, and adults landed significantly more on yellow paper moistened with honey-water. The next preferred colors were gray and white with the identical food source. Colors such as red, blue, green, brown, and black were least preferred by M. oedipus and attracted the adults on par with each other. The M. oedipus landings on petri dishes which held yellow-, gray-, and white-colored papers were significantly higher than the colorless petri dishes with olfactory stimuli only. There was no significant difference in landings on different-colored papers moistened with honey-water or with water alone in the morning compared with those in the evening. The cumulative response of M. oedipus to different-colored papers moistened with honey-water was significantly higher than the colored papers moistened with water only. Correspondingly, the response of M. oedipus to yellow-colored paper moistened with honey-water was significantly higher than the yellow-colored paper moistened with water only. Therefore, yellow paper moistened with honey-water can increase the feeding rate of M. oedipus and can be a potential technique in developing mass cultures for field release to control the invasive weed.

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

Diazinon has been used extensively in the past as part of California eradication programs for tephritid fruit flies (Diptera: Tephritidae) as a soil drench, but it is being phased out for this purpose in the United States. Therefore, in this study, the toxicity of Platinum, Force, Admire, Regent, and Warrior was estimated after application to sand and soil as drenches for control of the Mediterranean fruit fly, Ceratitis capitata (Wiedemann); melon fly, Bactrocera cucurbitae (Coquillett); and oriental fruit fly, Bactrocera dorsalis (Hendel), in Hawaii. Susceptibility of each species differed. In sand, the order of toxicity at LC₅₀ based on the 95% confidence limit overlap approach for C. capitata from most toxic to least toxic was diazinon > Force = Warrior > Admire = Platinum > Regent. The order of toxicity for B. dorsalis was diazinon > Platinum = Warrior = Force > Regent = Admire. The order of toxicity for B. cucurbitae was Warrior = diazinon > Force = Regent = Platinum = Admire. Based on the dose ratio method, Warrior was not significantly different at LC₅₀ than diazinon for B. cucurbitae only. All other insecticides were significantly different from diazinon at LC₅₀. Studies in sand were followed by an evaluation of specific concentrations of Warrior and Force in soil collected from two sites on the island of Kauai. Average concentrations that caused at least 95% mortality in soil in all three fruit fly species were 121 g active ingredient (AI)/ha for Force and 363 g (AI)/ha for Warrior compared with 182 g (AI)/ha for diazinon. These results indicate that Force and Warrior could be used as soil treatments for control of tephritid fruit flies.

The Mediterranean fruit fly, Ceratitis capitata (Wiedemann) (Diptera: Tephritidae), is one of the most important fruit pests worldwide. Mediterranean fruit fly control in Spain has been based on organophosphate sprays, especially malathion, mixed with protein baits. However, this insecticide has recently been excluded from annex 1 of the Directive 91/414 CEE, which lists authorized active ingredients for pest control in the European Union. This article reports on the efficacy of four alternative baited insecticides on Mediterranean fruit fly and their side effects on three natural enemies [Cryptolaemus montrouzieri (Mulsant), Neoseiulus californicus (McGregor), and Aphidius colemani (Viereck) ] relevant for pest control in citrus agroecosystems. A high Mediterranean fruit fly mortality was obtained for all baited insecticides (phosmet and spinosad) except lambda-cyhalothrin, which caused the lowest mortality and showed a novel disabling effect on surviving Mediterranean fruit fly adults. Spinosad proved to be the most selective bait treatment for C. montrouzieri and N. californicus, whereas for A. colemani the most selective bait was phosmet and lambda-cyhalothrin. These findings would contribute to a sustainable chemical control of C. capitata populations under an integrated pest management system in Spanish citrus orchards.

Antioxidant defense components protect insects by scavenging reactive oxygen species, leading to oxidative stress. I therefore investigated the effects of an organophosphorous insecticide, malathion, on superoxide dismutase (SOD) and acetylcholinesterase (AChE) activities as well as glutathione (GSH) and malondialdehyde (MDA) content as oxidative stress biomarkers in whole body of greater wax moth, Galleria mellonella (L.), larvae. Subcellular fractionation also was assayed for SOD and AChE enzymes to assess subcellular toxicity of malathion in this wax moth. The newly hatched larvae were reared on diets containing 0.01, 0.1, 1.0, and 10 ppm malathion. The diet with lowest concentration of malathion did not significantly influence MDA content and AChE activity. Malathion at 1.0 ppm significantly resulted in increased MDA content and decreased AChE activity. I observed a significant increase in SOD activity, whereas total GSH content and AChE activity were significantly lower for 1.0 ppm malathion than the control groups. Highest concentration of dietary malathion significantly decreased SOD and AChE activities, and GSH content in whole body of the insect. Subcellular fractionations showed that activities of microsomal and soluble AChE, and microsomal SOD for high concentrations of malathion (1.0 and 10 ppm) were significantly lower than control. Soluble SOD activities were significantly increased by low malathion concentrations, whereas only the highest malathion concentration resulted in significantly decreased SOD activity. I infer that induction of antioxidant defense mechanisms in response to increased oxidative stress may be a result of AChE inhibition by malathion in G. mellonella larvae.

The objective of this study was to assess the effect of fertilization (organic or synthetic) and cabbage, Brassica oleracea L., cultivars (‘K-Y cross’ and ‘Summer Summit’) on the chemistry of cabbage and on the responses of a cabbage specialist Pieris rapae crucivora Boisduval. Cabbages were grown from seeds in the greenhouse with either organic, synthetic, or no fertilizer treatments. Trials of ovipositional preference and larval feeding were conducted to evaluate the effect of foliage quality on insect responses. In addition, the foliar chemistry (water, nitrogen, total nonstructural carbohydrates, sinigrin, and anthocyanin) was measured during the insect bioassays. The results indicated that butterflies preferred to lay eggs on foliage of fertilized plants. The larvae grew faster on plants fertilized with synthetic fertilizer, but there was no evidence that contents of sinigrin delayed the developmental time of the larvae. However, plants that received organic fertilizer had higher biomass. In summary, the results of this study suggested that proper organic treatment can increase a plant's biomass production and may have a lower pest occurrence.

The assessment of pesticide effects in arthropods historically have relied heavily on acute lethal effects. Although the sublethal responses to such compounds are sometimes neglected, stimulatory effects associated with low doses of compounds toxic at higher doses, such as pesticides, have been widely reported in recent years and recognized as a general toxicological phenomenon. Evidence of such stimulatory response has also been reported among mites and a few insect pest-species exposed to pesticides and recognized as a one of the potential causes underlying pest resurgence and secondary pest outbreaks. However, fitness parameters and its implications were seldom considered in these studies and natural enemies are not usually target of attention. Here, we reported the stimulatory effect of sublethal doses (ranging from 0.02 to 172.00 ppb in addition to the control) of the pyrethroid permethrin topically applied to third instar nymphs of the spined soldier bug, Podisus distinctus (Stål) (Heteroptera: Pentatomidae). The parameters estimated from the fertility tables of insects exposed to the increasing doses of insecticide indicated a slight increase in the mean survival time for doses ≥0.20 ppb and a peak in the net reproductive rate at 1.72 ppb. This trend is coincident and correlated with the intrinsic rate of population growth (n = 18, r = 0.78, P = 0.0001), which also shows apeak at 1.72 ppb, leading to higher reproductive values of insects exposed to this dose. The phenomenon is consistent with insecticide-induced hormesis, for which the potential implications are discussed.

Pest management practices may be contributing to a decline in wild bee populations in or near canola (Brassica napus L.) agroecosystems. The objective of this study was to investigate the direct contact toxicity of five technical grade insecticides—imidacloprid, clothianidin, deltamethrin, spinosad, and novaluron—currently used, or with potential for use in canola integrated pest management on bees that may forage in canola: common eastern bumble bees [Bombus impatiens (Cresson); hereafter bumble bees], alfalfa leafcutting bees [Megachile rotundata (F.)], and Osmia lignaria Cresson. Clothianidin and to a lesser extent imidacloprid were highly toxic to all three species, deltamethrin and spinosad were intermediate in toxicity, and novaluron was nontoxic. Bumble bees were generally more tolerant to the direct contact applications > O. lignaria > leafcutting bees. However, differences in relative toxicities between the three species were not consistent, e.g., whereas clothianidin was only 4.9 and 1.3× more toxic, deltamethrin was 53 and 68× more toxic to leafcutting bees than to bumble bees and O. lignaria, respectively. Laboratory assessment of direct contact toxicity, although useful, is only one measure of potential impact, and mortality under field conditions may differ greatly depending on management practices. Research conducted using only honey bees as the indicator species may not adequately reflect the risk posed by insecticides to wild bees because of their unique biology and differential susceptibility. Research programs focused on determining nontarget impact on pollinators should be expanded to include not only the honey bee but also wild bee species representative of the agricultural system under investigation.

Boll weevil, Anthonomm grandis grandis Boheman (Coleoptera: Curculionidae), eradication programs typically equip pheromone traps with an insecticide-impregnated kill strip. These strips are intended to kill captured insects, thereby simplifying trap servicing and reducing the loss of weevils from predation and escape. However, the effectiveness of kill strips has not been extensively evaluated. We examined the influences of kill strips on weevil captures, trap servicing, and the incidences of weevil predation and trap obstruction (e.g., by spider webs). Evaluations were conducted weekly during three different production periods (pre- to early-, late-, and postseason) of cotton, Gossypium hirsutum L., to represent different environmental conditions and weevil population levels. Within each period, mean weekly captures of weevils in traps with and without kill strips were statistically similar. On average, traps with kill strips took 9 s longer to service than traps without kill strips, but statistical differences were only detected during the late-season period. Overall, the mean weekly proportion of traps with evidence of weevil predation or trap obstruction was significantly lower for traps with kill strips (0.25) than for traps without kill strips (0.37). However, this reduction in the frequency of weevil predation or trap obstruction was too small to produce a corresponding increase in the numbers of weevils captured. In light of these findings, the use of kill strips is likely unnecessary in eradication programs, but may be a consideration in situations when the numbers of deployed traps are reduced and chronic problems with weevil predation or trap obstruction exist.

The soybean aphid, Aphis glycines Matsumura (Hemiptera: Aphididae), is native to Asia and was recently (2000) detected in North America. Since then, it has become a significant threat to U.S. soybean production. Although neonicotinoid insecticide seed treatments, imidacloprid and thiamethoxam, have been suggested as a method of control, the season-long efficacy is still uncertain. Therefore, the use of imidacloprid and thiamethoxam seed treatments to control soybean aphid in Nebraska were examined. Soybean aphid populations were monitored weekly in an irrigated field study planted during the later half of the typical Nebraska planting window during 2005 and 2006. Imidacloprid and thiamethoxam were quantified by leaves through time, and leaf specific bioassays were conducted. In 2005, aphid populations were very low; however, in 2006 aphid numbers were significantly higher than 2005, reaching ≈1,200 aphids per plant in the untreated plots. Aphid injury significantly reduced yield and individual seed size in 2006. Imidacloprid significantly reduced aphid densities in 2006 but not below the economic threshold. In 2006, thiamethoxam held aphid densities below the economic threshold. Leaf specific bioassays and leaf specific imidacloprid and thiamethoxam quantification indicated that thiamethoxam was present in the plant at higher concentrations and for a longer period.

Walnut, Juglans regia L., is known for its insecticidal activities to a range of herbivores and microbes. Isolation and identification of bioactive compounds from walnut is a potential approach for the development of new pesticides. Laboratory experiments were carried out to investigate the acaricidal activities of green husk extracts of walnut. Bioassay-guided fractionation of petroleum-ether extracts of walnut led to the identification of a common plant-borne fatty acid ester, methyl palmitate (MP), which produced strong acaricidal activity (62.8% mortality) at 1 mg/ml at 24 h. The structure of MP was characterized with infrared spectrum and NMR, and the identification of MP confirmed using an authentic standard on high-performance liquid chromatography. Based on a slide dip bioassay, 10 mg/ml MP provided 97.9% mortality against adults of Tetranychus cinnabarinus (Boisduval) (Acari: Tetranychidae), whereas mortality against eggs was much lower (57.2%).

Basil oil and its three major active constituents (trans-anethole, estragole, and linalool) obtained from basil (Oscimum basilicum L.) were tested on three tephritid fruit fly species [Ceratitis capitata (Wiedemann), Bactrocera dorsalis (Hendel), and Bactrocera cucurbitae (Coquillett)] for insecticidal activity. All test chemicals acted fast and showed a steep dose-response relationship. The lethal times for 90% mortality/knockdown (LT₉₀) of the three fly species to 10% of the test chemicals were between 8 and 38 min. The toxic action of basil oil in C. capitata occurred significantly faster than in B. cucurbitae but slightly faster than in B. dorsalis. Estragole acted faster in B. dorsalis than in C. capitata and B. cucurbitae. Linalool action was faster in B. dorsalis and C. capitata than in B. cucurbitae. trans-Anethole action was similar to all three species. Methyl eugenol acted faster in C. capitata and B. cucurbitae than in B. dorsalis. When linalool was mixed with cuelure (attractant to B. cucurbitae male), its potency to the three fly species decreased as the concentration of cuelure increased. This was due to linalool hydrolysis catalyzed by acetic acid from cuelure degradation, which was confirmed by chemical analysis. When methyl eugenol (B. dorsalis male attractant) was mixed with basil oil, trans-anethole, estragole, or linalool, it did not affect the toxicity of basil oil and linalool to B. dorsalis, but it did significantly decrease the toxicity of trans-anethole and estragole. Structural similarity between methyl eugenol and trans-anethole and estragole suggests that methyl eugenol might act at a site similar to that of trans-anethole and estragole and serve as an antagonist if an action site exists. Methyl eugenol also may play a physiological role on the toxicity reduction.

Fall armyworm, Spodoptera frugiperda (J.E. Smith) (Lepidoptera: Noctuidae), is a major pest of corn, Zea mays L., and a significant, but more sporadic, pest of cotton, Gossypium hirsutum L., in the Western Hemisphere. Previous studies showed that the cotton infestations primarily involve a fall armyworm subpopulation known as the “corn-strain” for which corn is the preferred host plant. It was suggested that the fall armyworm infesting cotton originated in corn and spread into secondary hosts as their numbers increased. In this study, high positive correlations were found between corn acreage and fall armyworm infestation levels in cotton. These occurred between areas that are either geographically close or along plausible migration pathways. Formulae were derived from scatter plot and linear regression analysis that can predict infestation levels in cotton based on corn acreage. The implications of these results for describing and predicting fall armyworm population movements are discussed.

Reductions in oviposition and subsequent damage by root maggots (Diptera: Antho-myiidae, Delia spp.) to brassicaceous crops in the presence of nonhost plants has been demonstrated, but such investigations have not been conducted using intercrops of species commonly grown in the large-scale agricultural production systems of western Canada. A field experiment was conducted at three sites in Alberta, Canada, in 2005 and 2006 to determine interactions between root maggots and the various proportions of canola (Brassica napus L.) making up the total crop plant populations in intercrops with wheat (Triticum aestivum L.). The effect of a neonicotinoid seed treatment also was investigated. Root maggot damage to canola taproots decreased with increasing proportions of wheat in the intercrops. The presence of wheat in the intercrops had little effect on root maggot adult abundance in any single site-by-year combination or when data were combined over all sites and years, with different Delia species and sexes responding differently. Similarly, per plant root maggot egg populations were unaffected by intercropping, although egg populations were reduced on a per unit land area basis in intercrops compared with monocultures. Insecticidal seed treatment did not affect root maggot egg populations or canola root damage. Variable abundances and phenologies of the principal root maggot species infesting canola at different sites and years may influence their responses to canola-wheat intercrops. Intercropping canola and wheat may provide an opportunity for reducing crop damage from root maggot attack without compromising environmental sustainability.

From 2003 through 2007, densities of stink bugs were monitored weekly in 297 commercial production fields of early and late soybean, Glycine max L. Merrill, in southeast and southwest Arkansas. The goal of this research was to better understand seasonal abundance, species composition, and population dynamics of pentatomids as a benchmark reference for future management systems. Thirty-five percent of all the 25-sweep samples taken in soybean contained at least one stink bug specimen. The average density (mean ± SEM) of stink bugs across all soybean samples was 1.84 ± 0.06 per 25 sweeps. Overall, Nezara viridula L. was the most abundant species, although Euschistus servus (Say) was frequently found in soybean samples (18% of all samples). Peak densities of stink bugs in soybean were observed during the full-pod (R7) developmental stage. Approximately 25% of all soybean fields sampled had threshold densities (nine or more per 25 sweeps) at some time during the year, although 82 and 78% of fields in 2006 and 2007, respectively, reached threshold. At low densities (one to three stink bugs per 25 sweeps), E. servus comprised 50% of total stink bugs, but at high densities (>71 stink bugs per 25 sweeps), N. viridula comprised 81% of total stink bugs. Piezodorus guildinii (Westwood) was observed as apest of Arkansas soybean in 2005, and reproduction in soybean was documented in 2006 and 2007. Stink bugs seem to be a serious and increasingly important pest of soybean in southern Arkansas. Crop phenological development is a key factor in predicting colonization and population growth of stink bugs on Arkansas soybean, regardless of geographic region or type of soybean production system.

Freight transportation is an important pathway for the introduction and dissemination of exotic forest insects (EFI). Identifying the final destination of imports is critical in determining the likelihood of EFI establishment. We analyzed the use of regional freight transport information to characterize risk of urban and periurban areas to EFI introductions. Specific objectives were to 1) approximate the final distribution of selected imports among urban areas of the United States, 2) characterize the final distribution of imports in terms of their spatial aggregation and dominant world region of origin, and 3) assess the effect of the final distribution of imports on the level of risk to urban and periurban forests from EFI. Freight pattern analyses were conducted for three categories of imports whose products or packaging materials are associated with EFI: wood products, nonmetallic mineral products, and machinery. The final distribution of wood products was the most evenly distributed of the three selected imports, whereas machinery was most spatially concentrated. We found that the type of import and the world region of origin greatly influence the final distribution of imported products. Risk assessment models were built based on the amount of forestland and imports for each urban area. The model indicated that 84–88% of the imported tonnage went to only 4–6% of the urban areas in the contiguous United States. We concluded that freight movement information is critical for proper risk assessment of EFI. Implications of our findings and future research needs are discussed.

Diaphorina citri Kuwayama (Hemiptera: Psyllidae), vectors the bacterium Candidatus Liberibacter asiaticus, one of the causal organisms of the devastating citrus disease “huanglongbing” or citrus greening. In the United States, D. citri was first discovered in Florida, in 1998. Tamarixia radiata Waterston (Hymenoptera: Eulophidae) was imported from Asia and released in Florida in 1999–2001 to improve biological control of D. citri before citrus greening was detected in Florida in 2005. Florida citrus groves were surveyed during 2006 – 2007 for D. citri and T. radiata. Results showed that D. citri was established in all 28 citrus groves surveyed across 16 counties. Adult populations averaged 3.52, 1.27, and 1.66 individuals per “tap” sample at locations in the central, southwest, and eastern coastal regions, respectively. A tap sample consisted of 22- by 28-cm white paper sheet (on a clipboard) held under branches selected at random that were tapped three times. Averages of 67, 44, and 45% citrus shoots infested with psyllid eggs or nymphs were obtained in the central, southwest, and eastern coastal regions, respectively. T. radiata was recovered from fourth- and fifth-instar psyllid nymphs at 26 of the 28 locations. However, apparent parasitism rates were variable and averaged <20% during spring and summer over all locations. Incidence of parasitism increased during fall at some locations, averaging 39% in September and 56% in November in the central and southwest regions, respectively. Further efforts are warranted to enhance the biological control of D. citri and thereby reduce psyllid populations and spread of citrus greening disease.

The pepper weevil, Anthonomus eugeniiCano (Coleoptera: Curculionidae), is a major pest of cultivated peppers (Capsicum spp.) and other cultivated and wild species within the family Solanaceae. Laboratory study of this insect, as well as its biological control agents, will be greatly facilitated by an artificial rearing system that does not rely on pepper fruit. An egg collection method and amendments to a standard larval diet were investigated for use in the rearing of this weevil. Spherical sachets made of Parafilm or netting enclosing leaves of pepper, American black nightshade, eggplant, tomato, potato, and jasmine tobacco induced oviposition. Tomato, potato, and jasmine tobacco leaves were accepted despite the fact that these are not oviposition hosts for pepper weevils in the wild. A standard larval diet formula was modified in an attempt to improve egg hatch, larval survival, developmental time, and adult mass. The diet formula was modified with the addition of freeze-dried jalapeño pepper powder, an additional lipid source, alternate protein sources, and the removal of methyl paraben. None of the aforementioned treatments resulted in a significant improvement over the standard diet. Egg hatch was greater when eggs were incubated on moist paper towels rather than in diet; thus, placement of neonates rather than eggs into diet improved production of adults. Suggestions for more efficient rearing of weevils on the currently available diet and future directions for the development of an artificial rearing system for pepper weevil are discussed.

Acerola (Malpighia emarginata DC; Malpighiaceae) is an important fruit crop in Brazil. Among its pollinators, Centris (Heterocentris) analis (F.) stands out due to its abundance at flowers and prompt acceptance of trap-nests. For the first time, we propose the commercial use of Centris bees as orchard pollinators. To develop protocols for rearing and management of these bees, we analyzed trap-nest acceptance, brood-cell construction, and larval diet in Acerola orchards. Although Centris species, in general, use numerous pollen host plants, females of C. analis showed remarkable flower fidelity to Acerola for pollen supply when nesting in the orchard. Such fidelity was previously expected only for floral oil collection. The ease of acceptance of trap-nests by females of C. analis, their prolonged yearly activity period, multivoltine life history, and high pollinator efficiency characterize C. analis as an excellent potentially manageable pollinator in Acerola orchards.

Twospotted spider mite, Tetranychus urticae Koch (Acari: Tetranychidae), and hop aphid, Phorodon humuli (Schrank) (Hemiptera: Aphididae), are the most important arthropod pests of hop (Humulus lupulus L.) in the Northern Hemisphere. A potential barrier for greater adoption of conservation biological control strategies for spider mites and hop aphid is the extensive use of fungicides for management of hop powdery mildew, Podosphaera macularis (Wallr.:Fr.) U. Braun & S. Takamatsu. Field studies conducted in experimental plots in Oregon and Washington in 2005 and 2006 quantified the effects of powdery mildew fungicide programs (i.e., sulfur, paraffinic oil, and synthetic fungicides) on arthropod pests and natural enemies on hop. Fungicide treatment signifi-cantly affected spider mite populations in all four studies. Multiple applications of sulfur fungicides applied before burr development resulted in 1.4-3.3-fold greater spider mite populations during summer. Near the cessation of the sulfur applications, or after a lag of 20–30 d, spider mite populations increased significantly faster on sulfur treated plants compared with water-treated plants in three of four experiments. The effect of paraffinic oil on spider mites was varied, leading to exacerbation of spider mites in Oregon and Washington in 2005, suppression of mites in Oregon in 2006, and no significant effect compared with water in Washington in 2006. Significant relative treatment effects for cone damage due to spider mite feeding were detected in Oregon in 2005 in plots treated with sulfur and paraffinic oil compared with water and synthetic fungicides. Mean populations of hop aphids were similar among treatments in Oregon, although sulfur treatment suppressed hop aphid populations in Washington in 2005 and 2006. Populations of individual predacious insect species and cumulative abundance of macropredators were not consistently suppressed or stimulated by treatments in all trials. However, predatory mite abundance in Washington was affected by fungicide treatments, with plots treated with sulfur consistently having 10-fold fewer phytoseiids per leaf compared with the other treatments. Based on the results of these studies, powdery mildew fungicide programs that minimize or eliminate applications of sulfur and paraffinic oil would tend to conserve predatory mites and minimize the severity of spider mite outbreaks. However, mechanisms other than direct or indirect toxicity to phytoseiid mites likely are associated with exacerbation of spider mite outbreaks on hop.

Using multiple locations and a series of field trials over 2 yr, we evaluated an integrated pest management program for Ostrinia nubilalis (Hübner) (Lepidoptera: Crambidae) management in peppers involving biorational chemistries, inundative releases of Trichogramma ostriniae (Pang & Chen), and conservation of generalist predators. In small plot trials, three biorational insecticides (spinosad, indoxacarb, and methoxyfenozide) provided comparable control of O. nubilalis as two broad-spectrum conventional insecticides (acephate and lambda-cyhalothrin). However, lambda-cyhalothrin at most locations, and indoxacarb at one location, resulted in outbreaks of green peach aphids. We also observed significant effects on the generalist predator community: beneficial communities in methoxyfenozide-treated plots were most similar to untreated controls, and acephate-treated plots were the least similar. Management systems comparing untreated controls, inundative release of T. ostriniae with methoxyfenozide applied when lepidopterans exceeded thresholds, or weekly applications of acephate or lambda-cyhalothrin, showed no effects on marketable fruit or percentage of fruit damaged, but the conventional insecticide approach caused aphid flares. Inun-dative releases of T. ostriniae and biorational chemistries provide a more environmentally sound approach to managing O. nubilalis in peppers, due, in part, to conservation of generalist predators.

A trial was conducted in a commercial Citrus sinensis L. variety ‘Washington’ navel orange orchard to compare the coverage and efficacy against citricola scale Coccus pseudomagnoliarum (Kuwana) (Hemiptera: Coccidae) of 45.5 liters/ha of an nC24 agricultural mineral oil treatment applied by two different methods: a conventional air blast sprayer and a rotary atomizer. Three water volumes (2,340, 4,680, and 7,020 liters/ha) were applied with the air blast sprayer to determine the optimal spray volume for that equipment. A single volume (2,340 liters/ha) was applied with the rotary atomizer to compare its effectiveness with that of the air blast sprayer at this same volume. Results demonstrated that all treatments reduced citricola scale densities. Moreover, all treatments conducted with the air blast sprayer provided significantly greater coverage and significantly reduced citricola scale densities compared with the treatment made with the rotary atomizer. Larger water volume applications with the air blast sprayer did not significantly reduce citricola scale densities, although significantly better coverage was attained in the interior of the tree when spraying with 4,680 and 7,020 liters/ha. As a consequence, this study demonstrated that the increased coverage obtained by applying higher water volume with the air blast sprayer was not required for an optimal treatment in August, when the citricola scale population consisted of nymphs inhabiting the outside leaves of the tree.

The toxicity of eight botanically based biopesticides was evaluated against third instars of the scarab larvae (Coleoptera: Scarabaeidae) Popillia japonica Newman, Rhizotrogus majalis (Razoumowsky), Anomala orientalis Waterhouse, and Cyclocephala borealis Arrow. Soil dip bioassays were used to obtain concentration-mortality data 7 d after treatment of larvae, leading to the calculation of LC₅₀ and LC₉₀ values. A wide range in LC₅₀ and LC₉₀ values were exhibited among the formulations. The product Armorex was one of the most active formulations against P. japonica (LC₅₀ = 0.42 ml/liter), R. majalis (LC₅₀ = 0.48 ml/liter), A. orientalis (LC₅₀ = 0.39 ml/liter), and C. borealis (LC₅₀ = 0.49 ml/liter). Armorex is composed of extracts from diverse botanical sources, including 84.5% sesame oil, 2.0% garlic oil, 2.0% clove oil, 1.0% rosemary oil, and 0.5% white pepper extracts. The product Azatin, composed of 3% azadirachtin, also exhibited high toxicity to P. japonica (LC₅₀ = 1.13 ml/liter), R. majalis (LC₅₀ = 0.81 ml/liter), and A. orientalis (LC₅₀ = 1.87 ml/liter). Veggie Pharm is composed of extracts from diverse sources, but this product showed the lowest toxicity to P. japonica (LC₅₀ = 35.19 ml/liter), R. majalis (LC₅₀ = 62.10 ml/liter), A. orientalis (LC₅₀ = 43.76 ml/liter), and C. borealis (LC₅₀ = 50.24 ml/liter). These results document the potential for botanical formulations to control white grubs, but blending extracts from diverse botanical sources does not ensure enhanced biological activity.

Billbugs (Coleoptera: Curculionidae: Sphenophorus spp.) are common pests whose damage is often misdiagnosed on turfgrass in the United States. Consequently, Florida turfgrass managers have been struggling to satisfactorily control billbug outbreaks. Thus, we sought to determine the species complex, abundance, seasonality, and fecundity of key Sphenophorus spp. from field collections, and quantify duration of developmental and daily activity periods through greenhouse rearing tests. From January 2006 to December 2007, > 18,000 adults of 10 different Sphenophorus spp. were collected from four linear pitfall traps on each of two golf courses in north central and two courses in southern Florida. Sphenophorus venatus vestitus Chittenden was the most abundant species, making up >94% of all specimens collected from three of the four golf courses (80.9% of all specimens collected). Adults were active and mature eggs were present in female ovaries nearly every week of the year. Adults were nocturnal. S. v. vestitus development from egg to adult can occur in 8–9 wk on ‘Tifway’ bermudagrass [Cynodon dactylon (L.) Pers.] or ‘Empire’ zoysiagrass (Zoysia japonica Steud.), with up to six overlapping generations per year, depending on environmental conditions. Thus, any time of year could be suitable to target either adults or larvae, and a repeated application may be needed to manage subsequently emerged larvae or eclosed adults.

Five formulations of controlled release, polyethylene tube dispensers of pheromone were evaluated during three field seasons for disruption of codling moth, Cydia pomonella (L.) (Lepidoptera: Tortricidae), and the oriental fruit moth, Grapholita molesta (Busck) (Lepidoptera: Tortricidae). Evaluations were conducted in replicated 4-ha plots of commercial apple in Michigan. Disruption of both C. pomonella and G. molesta male orientation to pheromone traps in plots treated with a dual-species formulation (Isomate CM/OFM TT), simultaneously releasing the pheromone components of both C. pomonella and G. molesta, was equivalent to that obtained by treating plots with separate formulations for each species (Isomate C Plus or Isomate C TT for C. pomonella and Isomate M Rosso for G. molesta) through mid-season. However, disruption efficacy of the dual-species formulation was significantly lower near the end of the season for G. molesta compared with the Isomate M Rosso formulation because of depletion of active ingredients and coincided with a slight increase in fruit injury. Effective disruption of C. pomonella and G. molesta also was obtained with a multispecies formulation (Isomate CM/OFM/LR) that releases the main pheromone components of C. pomonella, G. molesta, and several leafroller species. Each formulation type releasing (E,E)-8,10-dodecadien-1-ol (codlemone) also was found to release the E,Z- and Z,E-isomers of codlemone. Our data provide further evidence that simultaneous disruption of C. pomonella and G. molesta with dispensers releasing both species'pheromone components is possible; however, the controlled release formulations tested here require modification or postponed deployment coupled with early season control by other means to achieve season-long efficacy. Simultaneous disruption of several species with a single formulation will be economically advantageous in regions where control of multiple pests is needed given the need for hand application of this technology.

The effects of three sulfur products (calcium polysulfide [ = lime sulfur], dry flowable sulfur, and ammonium thiosulfate, a plant nutrient), were tested in bioassays against a predatory mite, Galandromus occidentalis (Nesbitt), and two species of tetranychid (pest) mites, twospotted spider mite (Tetranychus urticae Koch) and European red mite [Panonychus ulmi (Koch)]. Calcium polysulfide and ammonium thiosulfate were acutely toxic on contact to adult females of all three mite species, causing 58–100% mortality in 48 h. Dry flowable sulfur, in contrast, was nontoxic to adults of all three species. Fresh residues of the sulfur products were essentially nontoxic to females of G. occidentalis and T. urticae. Galandromus occidentalis consumed 8.2 and 4.0× fewer prey contaminated with residues of calcium polysulfide and ammonium thiosulfate; dry flowable sulfur had no effect on prey consumption. Higher posttreatment temperatures (32 versus 18°C) did not affect the toxicity of dry flowable sulfur to G. occidentalis and T. urticae. The toxic effect of the sulfur products was not related to the concentration of elemental S but rather to some intrinsic characteristic of the compound itself. There were substantial differences in the responses of different stages of G. occidentalis. Residues that were nontoxic to adult females were highly toxic to hatching larvae, including those of dry flowable sulfur. In addition, all three products were highly repellent to adult female G. occidentalis. The lethal effect of calcium polysulfide on larvae was still present when the laboratory-aged residues onbean leaves were 8–9 d old. Field-aged residues on apple (Malus spp.) leaves were highly toxic (89% mortality) after 7 d, but mortality declined to 50 and 17% after 14 and 22 d, respectively. The increasing use of sulfur-containing products is detrimental to predatory mites and may play a role in the diminishing effectiveness of integrated mite control in Washington apple orchards.

Efficacy, costs, and impact on crop salability of various biological and chemical control strategies for Tetranychus urticae Koch (Acari: Tetranychidae) were evaluated on mixed plantings of impatiens, Impatiens wallerana Hook.f (Ericales: Balsaminaceae), and ivy geranium, Pelargonium peltatum (l.) L'Hér. Ex Aiton (Geraniales: Geraniaceae), cultivars in commercial greenhouses. Chemical control consisting of the miticide bifenazate (Floramite) was compared with two biological control strategies using the predatory mite Phytoseiulus persimilis Athias-Henriot (Acari: Phytosei-idae). Treatments were 1) a single, early application of bifenazate; 2) a single, early release of predatory mites at a 1:4 predator:pest ratio based on leaf samples to estimate pest density; 3) a weekly release of predatory mites at numbers based on the area covered by the crop; and 4) an untreated control. T. urticae populations were monitored for 3 wk after the earliest treatment. When plants were ready for market, their salability was estimated. Bifenazate and density-based P. persimilis treatments effectively reduced T. urticae numbers starting 1 wk after plants had been treated, whereas the scheduled, area-based P. persimilis treatment had little or no effect. The percentage of flats that could be sold at the highest market wholesale price ranged from 15 to 33%, 44 to 86%, 84 to 95%, and 92 to 100%, in the control, weekly area-based P. persimilis, bifenazate, and single density-based P. persimilis treatments, respectively. We have shown that in commercial greenhouse production of herbaceous ornamental bedding plants, estimating pest density to determine the appropriate number of predators to release is as effective and offers nearly the same economic benefit as prophylactic use of pesticides.

The susceptibility to fipronil of U.S. and French populations of Reticulitermes flavipes (Kollar) (Isoptera: Rhinotermitidae) was evaluated in two types of laboratory bioassays: contact intoxication with 0.01–1 ppm treated sand and feeding intoxication with 0.1–10 ppm treated filter paper. Contact intoxication with 0.01 ppm fipronil caused 60% mortality after 55 and 64 h in the French and U.S. populations, respectively, whereas in the 5 ppm feeding assay 70 and 60% mortality was observed after 7 d in the French and U.S. populations, respectively. We evaluated the uptake, clearance, and transfer of fipronil among workers of French R. flavipes using [¹⁴C]fipronil in contact (0.01 ppm) and feeding (3 ppm) bioassays. Fipronil amounts were measured on their cuticle and in their bodies. Maximal uptake was observed in the contact assay. A significant uptake of fipronil occurred in the feeding assay. Transfer from exposed donors to unexposed recipients occurred within 24 h. Frequent horizontal transfer resulted in a significant uptake in recipients, particularly when donor fipronil acquisition was by feeding. Donors transferred ≈46% of the toxicant to recipients. Social behaviors such as contact and grooming, together with internalization of the biocide, may be components of the horizontal transfer process and contribute to the efficacy of fipronil in the field.

The sublethal effects of the insecticide spinosad were assessed against Plutella xylostella (L.) (Lepidoptera: Plutellidae) by using a demographic approach. The resulting data were analyzed based on the age-stage and two-sex life table model. Bioassay results showed that the susceptibility of P. xylostella to spinosad decreased in Sub strains selected by LC₂₅ spinosad for 10 generations. Although the egg size was significantly smaller in Sub-1 (selected by LC25 spinosad for one generation) compared with spinosad-susceptible strain SS, egg size recovered to normal levels in Sub-5 (selected by LC₂₅ spinosad for five generations) and were even larger in Sub-10 (selected by LC₂₅ spinosad for 10 generations). The life-history parameters changed in the Sub strains of different generations. Sublethal spinosad had a significant effect on Sub-1; however, the sublethal effect on the Sub strains decreased as selection cycles increased. The intrinsic rate of increase (r_m), finite rate of increase (λ) and net reproductive rate (R₀) in Sub-1 were significantly decreased compared with those in the SS strain. No significant differences were found between the Sub-5 or Sub-10 compared with the SS strain. The greatest difference was observed in the total number of eggs laid by each female, i.e., the fecundity. The fecundity in SS, Sub-1, Sub-5, and Sub-10 were 121.92, 81.26,114.42, and 159.21, respectively. The life expectancy of an SS, Sub-1, Sub-5, and Sub-10 egg was 10.58, 8.71, 10.21, and 7.45 d, respectively.

The γ-amino butyric acid (GABA)-gated chloride ion channel in the insect central nervous system is the target of cyclodiene and phenylpyrazole insecticides. Resistance to dieldrin has been reported in several insect species and was associated with a point mutation (Ala²⁸⁵ to Ser substitution) in the M2 transmembrane domain of the GABA-gated chloride ion channel (the resistant to dieldrin [Rdl] gene). A partial Rdl gene sequence was reported previously in specimens of the cat flea, Ctenocephalides felis (Bouché). Because the presence of the Rdl gene mutation coincided with a reduction in susceptibility to fipronil in some insect species, it has been inferred that a similar association may exist in cat fleas. The Rdl gene sequence was evaluated in 20–50 fleas each from six cat flea strains shown previously to be fully susceptible to fipronil. Total DNA or RNA from fleas was extracted using a commercial kit, and the sequence encompassing the single nucleotide polymorphism (SNP) position Rdl was amplified by polymerase chain reaction (PCR) or reverse transcription-PCR. Amplification products were sequenced on both strands. All tested strains were homozygous for the mutant allele (T nucleotide at SNP position); amino acid sequencing demonstrated the Ala²⁸⁵ to Ser substitution. The results of this study indicated that the Rdl gene mutation was uniformly present as homozygous alleles in strains of fleas that have been shown to be fully susceptible to topically applied fipronil and that the efficacy of fipronil against cat fleas was not impacted by the Rdl gene mutation.

Mutations associated with pyrethroid resistance were found in Mexican strains of Rhipicephalus microplus (Canestrini). A mutation in the sodium channel gene was reported in strains highly resistant to permethrin and another mutation in an esterase gene in a strain that shows moderate resistance to the same pesticide. Methods based on the melting temperature difference of amplified allele-specific DNA fragments were developed that can detect these mutations rapidly in individual larvae. When these methods were applied to ticks from various strains of R. microplus from Australia, neither of these mutations could be demonstrated. Different resistance mechanisms have apparently developed independently between Australian and Mexican strains of R. microplus.

The tobacco budworm, Heliothis virescens (F.) (Lepidoptera Noctuidae), is one of the most important pests of cotton, Gossypium hirsutum L., that has become resistant to a wide range of synthetic insecticides. Cry1Ac-expressing cotton has proven its effectiveness against this insect since its introduction in North America in 1996. However, the constant exposure of tobacco budworm to this protein toxin may result in the development of resistance to it. To estimate the frequency of alleles that confer resistance to a 1.0 µg of Bacillus thuringiensis Cry1Ac diagnostic concentration in field-collected insects, the second generation (F₂) of 1,001 single-pair families from seven geographical regions representing 2,202 alleles from natural populations was screened in 2006 and 2007 without finding major resistant alleles. Neonates of 56 single-pair families were able to develop to second instar on the diagnostic concentration in the initial screen, but only seven of these lines did so again in a second confirmatory screen. Minor resistance alleles to Cry1Ac may be quite common in natural populations of H. virescens. Our estimated resistance allele frequencies (0.0036 – 0.0263) were not significantly different from a previously published estimate from 1993. There is no evidence that H. virescens populations have become more resistant to Cry1Ac.

Topical application bioassays of bifenthrin and λ-cyhalothrin were conducted on field-collected populations of Listronotus maculicollis Kirby (Coleoptera: Curculionidae) from eight southern New England golf courses, six in Connecticut, one in Massachusetts, and one in Rhode Island. Concentrations versus mortality regression lines were estimated to compare the LD₅₀ values and resistance ratios for each insecticide and each population. The LD₅₀ ranges for bifenthrin and λ-cyhalothrin were 1.80–244.67 ng per insect and 0.52–159.53 ng per insect, respectively. The field-collected strains showed low to high levels of resistance to bifenthrin (6.1–135.9-fold) and λ-cyhalothrin (28.7–306.8-fold). This is the first report of insecticide resistance in this species. The loss of pyrethroid efficacy is making control of Listronotus maculicollis more challenging.

The insecticidal efficacy of mixtures of acrinathrin (pyrethroid) with carbamate fungicides (propamocarb, carbendazim, iprovalicarb, and diethofencarb) and insecticides (carbaryl, thiodicarb, pirimicarb, and oxamyl) was studied in a field strain of Frankliniella occidentalis (Per-gande). The fungicide propamocarb and the insecticides pirimicarb and oxamyl were selected for further studies of their synergism action with more detailed bioassays. The method consisted of combining increasing concentrations of acrinathrin with a constant sublethal rate of the carbamate as synergist. These three carbamates did not show synergism to acrinathrin in a laboratory insecticide-susceptible strain, but they did in two field strains, with higher acrinathrin resistance corresponding to higher synergism. Carbamates such as pirimicarb, oxamyl, and propamocarb could be practical candidates for field use as synergists, even against other pests with metabolic resistance.

Examination of DNA sequences of the 5′ end of the mitochondrial cytochrome oxidase I gene of Aulacorthum solani (Kaltenbach) (Hemiptera: Aphididae) reveals little variation between samples from broad geographic provenances. The apparent genetic similarity despite A. solani's morphological and biological differences contrasts with the species complexes of other aphid pests.

The polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) method described in a previous publication to document worldwide population structure of Mediterranean fruit flies and analyze probable sources of fly introductions is re-evaluated. Analysis of representatives of the RFLP-based markers using the ND5-tRNA-ND4 mitochondrial locus through DNA sequencing shows that the original markers produced haplotypes that are homoplasic and exclude valuable information. DNA sequences also identified errors in data generated with the protocol because of failure of the XbaI enzyme to efficiently cut PCR product. In all, the PCR-RFLP method is able to document haplotypes present in medfly populations outside of Sub-Saharan Africa and is a cost-effective approach to pathway analysis. New primer pairs for analysis of this locus are reported that reduce the number of PCR steps required to analyze the RFLP marker and the time of each PCR run. For comparison of the PCR-RFLP method, the utility of a DNA sequence-based approach to Mediterranean fruit fly pathway analysis is reported using the ND5-ND4 locus and the proposed “barcode region” of the COI gene. Both gene sequences are more informative than the PCR-RFLP method and document high genetic variation within Sub-Saharan Africa. Application of these methods as tools and their interpretation is discussed.

The impact of feeding injury by the Russian wheat aphid, Diuraphis noxia (Mordvilko) (Hemiptera: Aphididae), and bird cherry-oat aphid, Rhopalosiphum padi (L.) (Hemiptera: Aphidi-dae) on susceptible and resistant wheat, Triticum aestivum L., near-isogenic lines ‘Tugela’ (susceptible), Tugela-Dn1 (antibiotic), Tugela-Dn2 (tolerant), and Tugela-Dn5 (antixenotic) was evaluated by assessing photosynthetic parameters. Photosynthesis and closely related parameters, pigment composition, and nonstructural carbohydrates were measured at 1, 3, and 9 d after aphids were introduced on plants maintained under greenhouse conditions. Overall, R. padi had a higher reproductive capacity within a period of 9 d compared with D. noxia on all lines except Tugela-Dn2. Although the visible injury symptoms associated with aphid injury can be highly species specific, the data indicate that photosynthetic reduction is a common physiological pattern of wheat response to aphid feeding, irrespective of chlorosis elicitation. Although both aphids negatively affected net photosynthesis, D. noxia had a greater impact than R. padi, even when aphid numbers were considerably fewer for D. noxia (100–150 aphids per plant) compared with R. padi (>200 aphids per plant). The photosynthetic pigment and carbohydrate data suggest that the initial net photosynthesis reduction elicited by aphid feeding may not be directly related to the light reaction portion of the photosynthetic pathway via pigment losses. It is also unlikely that source-sink manipulation is the primary cause for the observed short-term inhibition of photosynthesis.

Wild relatives of potato offer a tremendous germplasm resource for breeders. Because the germplasm base of potato is so broad and diverse, we have undertaken a series of studies to determine whether we can predict the distribution of valuable genes in wild Solanum species based on taxonomic or biogeographic data. This is the third study in the series. Resistance to defoliation by Colorado potato beetle, Leptinotarsa decemlineata Say, larvae was evaluated in 156 accessions of 41 wild Solanum species. The highest frequencies of resistant accessions were found in diploid species with an endosperm balance number of 1. In contrast to previous studies on resistance to foliar fungal pathogens, there was little variability in defoliation scores among plants within an accession and among accessions within a species, at least for the most resistant species. There was no strong association of Colorado potato beetle resistance in wild potato species to biogeographic data. Resistance was confirmed in species previously characterized by high levels of glycoalkaloids or dense glandular trichomes. However, we have identified additional species with resistance to the Colorado potato beetle. Mechanisms of resistance are being studied in these species and attempts will be made to introgress them into the cultivated potato.

Southern chinch bug, Blissus insularis Barber (Hemiptera: Blissidae), is the most serious insect pest of St. Augustinegrass Stenotaphrum secundatum (Walter) Kuntze, a common lawngrass grown in southeastern U.S. states. Host plant resistance to southern chinch bug has been identified in the polyploid St. Augustinegrass‘FX-10′ and the diploid ‘Captiva’. The objective of this research was to identify possible physical mechanism(s) explaining chinch bug resistance in these cultivars. We studied the distribution of chinch bug salivary sheaths in the preferred tissue for feeding (the axillary shoot) of the two resistant cultivars and two susceptible cultivars, paired for ploidy (‘Floratam’, polyploid, and Palmetto, diploid). We also investigated the potential role of axillary shoot lignification and anatomy in chinch bug resistance. Salivary sheaths were more abundant on the outermost leaf sheath of axillary shoots of resistant cultivars compared with susceptible cultivars. In contrast, fewer salivary sheaths reached the innermost meristematic tissue in the axillary shoots of resistant St. Augustinegrass cultivars than in the two susceptible cultivars. The polyploid cultivars FX-10 and Floratam had higher total lignin in axillary shoots compared with the diploid cultivars Captiva and Palmetto. However, total lignin content was not correlated with resistance to southern chinch bug. Light microscopic studies found no differences in epidermal layer thickness among resistant and susceptible St. Augustinegrass cultivars. However, transmission electron microscopic studies revealed that the cell walls of the sclerenchyma cells around the vascular bundle of southern chinch bug-resistant FX-10 and Captiva were significantly thicker than the cell walls in susceptible Floratam and Palmetto. Our research suggests that the thick-walled sclerenchyma cells around the vascular bundle play a role in southern chinch bug resistance in St. Augustinegrass, possibly by reducing stylet penetration to the vascular tissue.

Insect biotypes are populations able to kill or injure crops with resistance genes and complicate pest management programs based on host plant resistance. Biotypes occur in Russian wheat aphid, Diuraphis noxia (Kurdjumov) (Hemiptera: Aphididae), a worldwide pest of wheat, Triticum aestivum L., and barley, Hordeum vulgare L., that was introduced into Mexico in 1980 and then spread into Texas by 1986. Five D. noxia biotypes were described in the United States and given the number designations 1 through 5. Of these, only Biotypes 1 and 2, which are nondamaging and damaging to Dn4-resistant wheat, respectively, are common and agriculturally important. Only a single clone of Biotypes 3, 4, and 5 were found in nature and now exist in the laboratory. The biotypes were found after 5 yr of the commercial planting of resistant wheat and their origin is unknown. To understand the genetic relatedness and origin of D. noxia biotypes in the United States, we used three molecular markers to assay for genetic variation within and between Biotypes 1 and 2, and for variation between Biotypes 1, 2, 3, 4, and 5. A single random amplified polymorphic DNA polymorphism was found in only two individuals. No DNA sequence variation in the cytochrome oxidase subunit I mitochondrial gene was found between 26 D. noxia clones. No variation was found at seven examined simple sequence repeat loci. Results suggest Biotype 2 originated from the extant population and does not represent a second introduction of a genetically divergent biotype.

Yellow sticky card traps were assessed as a tool for estimating absolute densities of adult Diaphorina citri Kuwayama (Hemiptera: Psyllidae) in citrus. Weekly trapping was conducted in young and mature trees with traps deployed directly in trees, one trap per tree. In addition, a comparison was made between one and three traps per tree in the mature trees. Solar radiation was positively correlated with numbers of adults trapped per week in both groups of trees. Air temperature was positively correlated with captures of adults in the mature trees. The value of traps as indicators of absolute densities of adults was therefore reduced by changes in sunlight and temperature. Captures of adults were not reduced by rain. A positive correlation was found for data from the young trees between trap captures of adults and maximum daily wind speed. Significant correlations were found between numbers of adults on leaves and traps. However, little confidence could be placed on individual predictions of adult densities on leaves based on numbers of adults on traps. Increasing the number of traps per tree from one to three did not improve individual estimates, although detection of adults in trees was improved using three traps when adult population levels were low. A better quantitative relationship between adults on traps and leaves might have been determined if greater sample sizes had been used to estimate densities. Regardless, day-to-day differences in sunlight and air temperature will influence numbers of adults captured on traps, thus reducing the value of traps as indicators of absolute densities.

The extent to which a carrier powder was taken up and horizontally transferred by contaminated Indianmeal moth, Plodia interpunctella (Hübner) individuals to conspecifics was evaluated. Using a marker dye, which was shown to be colocalized with the carrier powder, the amount of powder on the Indianmeal moth, as determined by spectrophotometry, was correlated with quantification based on a novel image analysis approach that enabled differentiation of powder uptake by body region. Over a 48-h period, more powder was retained on the ventral surface than the dorsal side, with the head region showing the greatest amount of powder uptake and retention. During courtship, powder was horizontally transferred by treated males to 1.6% of the head and 0.06% of the untreated females' body. To inoculate moths, a pit-fall style autodissemination station was determined as being more effective than a powder tray, as significantly more material was taken up to the key areas of the moth's body where powder is more effectively retained and more likely to be horizontally transferred. Additionally, a pit-fall station prevented moths from exhibiting avoidance behavior from the powder, which was frequently encountered if they had to walk into a powder tray.This study shows that different regions of the Indianmeal moth body vary in capacity to carry powder and that future research efforts should target these specific regions. Although the proposed autodissemination system was optimized for management strategies of Indianmeal moth, we believe the results presented here can be used to develop novel management strategies for other insect pests.