The moth Lobesia botrana (Denis & Schiffermüller) (Lepidoptera: Tortricidae) feeds on grapes (Vitis vinifera L.), reducing yield and increasing susceptibility to fungal infections. L. botrana is among the most economically important insects in Europe and has recently been found in vineyards in Chile, Argentina, and California. Here, we review L. botrana biology and behavior in relation to its larval host (the grapevine) and its natural enemies. We also discuss current and future control strategies in light of our knowledge of chemical ecology, with an emphasis on the use of the sex pheromone-based strategies as an environmentally safe management approach. Pheromone-mediated mating disruption is the most promising technique available on grapes and is currently implemented on ≈140,000 ha in Europe. Experience from several growing areas confirms the importance of collaboration between research, extension, growers, and pheromone-supply companies for the successful implementation of the mating disruption technique. In the vineyards where mating disruption has been successfully applied as an areawide strategy, the reduction in insecticide use has improved the quality of life for growers, consumers, as well as the public living near wine-growing areas and has thereby reduced the conflict between agricultural and urban communities.

Approximately US$1.3 billion is spent each year on insecticide applications in major row crops. Despite this significant economic importance, there are currently no widely established decision-support tools available to assess suitability of spray application conditions or of the predicted quality or performance of a given commercial insecticide applications. We conducted a field study, involving 14 commercial spray applications with either fixed wing airplane (N = 8) or ground rig (N = 6), and we used environmental variables as regression fits to obtained spray deposition (coverage in percentage). We showed that 1) ground rig applications provided higher spray deposition than aerial applications, 2) spray deposition was lowest in the bottom portion of the canopy, 3) increase in plant height reduced spray deposition, 4) wind speed increased spray deposition, and 5) higher ambient temperatures and dew point increased spray deposition. Potato psyllid, Bactericera cockerelli (Sulc) (Hemiptera: Triozidae), mortality increased asymptotically to ≈60% in response to abamectin spray depositions exceeding around 20%, whereas mortality of psyllid adults reached an asymptotic response ≈40% when lambda-cyhalothrin/thiamethoxam spray deposition exceeded 30%. A spray deposition support tool was developed ( http://pilcc.tamu.edu/) that may be used to make decisions regarding 1) when is the best time of day to conduct spray applications and 2) selecting which insecticide to spray based on expected spray deposition. The main conclusion from this analysis is that optimization of insecticide spray deposition should be considered a fundamental pillar of successful integrated pest management programs to increase efficiency of sprays (and therefore reduce production costs) and to reduce risk of resistance development in target pest populations.

A high proportion of nonreproductive (NR) Varroa destructor Anderson & Trueman (Mesostigmata: Varroidae), is commonly observed in honey bee colonies displaying the varroa sensitive hygienic trait (VSH). This study was conducted to determine the influence of brood removal and subsequent host reinvasion of varroa mites on mite reproduction. We collected foundress mites from stages of brood (newly sealed larvae, prepupae, white-eyed pupae, and pink-eyed pupae) and phoretic mites from adult bees. We then inoculated these mites into cells containing newly sealed larvae. Successful reproduction (foundress laid both a mature male and female) was low (13%) but most common in mites coming from sealed larvae. Unsuccessful reproductive attempts (foundress failed to produce both a mature male and female) were most common in mites from sealed larvae (22%) and prepupae (61%). Lack of any progeny was most common for mites from white-eyed (83%) and pink-eyed pupae (92%). We also collected foundress mites from sealed larvae and transferred them to cells containing newly sealed larvae, prepupae, white-eyed pupae, or pink-eyed pupae. Successful reproduction only occurred in the transfers to sealed larvae (26%). Unsuccessful reproductive attempts were most common in transfers to newly sealed larvae (40%) and to prepupae (25%). Unsuccessful attempts involved the production of immature progeny (60%), the production of only mature daughters (26%) or the production of only a mature male (14%). Generally, lack of progeny was not associated with mites having a lack of stored sperm. Our results suggest that mites exposed to the removal of prepupae or older brood due to hygiene are unlikely to produce viable mites if they invade new hosts soon after brood removal. Asynchrony between the reproductive status of reinvading mites and the developmental stage of their reinvasion hosts may be a primary cause of NR mites in hygienic colonies. Even if reinvading mites use hosts having the proper age for infestation, only a minority of them will reproduce.

Pollination services of pumpkin, Cucurbita pepo L., provided by the European honey bee, Apis mellifera L., were compared with two native bee species, the common eastern bumble bee, Bombus impatiens (Cresson), and Peponapis pruinosa Say, in New York from 2008 to 2010. Performance of each species was determined by comparing single-visit pollen deposition, percentage of visits that contacted the stigma, flower-handling time, fruit and seed set, and fruit weight per number of visits. Fruit yield from small fields (0.6 ha) supplemented with commercial B. impatiens colonies was compared with yield from those not supplemented. A. mellifera spent nearly 2 and 3 times longer foraging on each pistillate flower compared with B. impatiens and P. pruinosa, respectively. A. mellifera also visited pistillate flowers 10–20 times more frequently than B. impatiens and P. pruinosa, respectively. Yet, B. impatiens deposited 3 times more pollen grains per stigma and contacted stigmas significantly more often than either A. mellifera or P. pruinosa. Fruit set and weight from flowers visited four to eight times by B. impatiens were similar to those from open-pollinated flowers, whereas flowers pollinated by A. mellifera and P. pruinosa produced fewer fruit and smaller fruit compared with those from open-pollinated flowers. Fields supplemented with B. impatiens produced significantly more pumpkins per plant than nonsupplemented fields. B. impatiens was a better pollinator of pumpkin than P. pruinosa and should be considered as a promising alternative to A. mellifera for pollinating this crop.

A significant concern in the commercial application of the alfalfa leafcutting bee, Megachile rotundata (F.) (Hymenoptera: Megachilidae), for pollination is synchronizing bee emergence and activity with peak crop bloom. Previous studies have demonstrated that the commercial spring incubation of this species can be successfully interrupted by low temperature incubation, thereby slowing development and giving producers flexibility in timing emergence to weather conditions or crop bloom. In this study, we demonstrate that the implementation of a fluctuating thermal regime, during which bees are given a daily one hour pulse of high temperature, markedly increases the “shelf-life” of individuals of this species. Although constant temperatures can be used to store bees for up to 1 wk with no decrease in survival, properly staged bees can be stored for up to 6 wk without a significant decrease in percentage of emergence. Hence, we expect fluctuating thermal regime protocols to become a valuable tool for M. rotundata managers, especially when timing nesting activity with peak bloom to maximize effectiveness.

Yellow dwarf is a major disease problem of wheat, Triticum aestivum L., in Alabama and is estimated to cause yield loss of 21–42 bu/acre. The disease is caused by a complex of viruses comprising several virus species, including Barley yellow dwarf virus-PAV and Cereal yellow dwarf virus-RPV. Several other strains have not yet been classified into a specific species. The viruses are transmitted exclusively by aphids (Hemiptera: Aphididae). Between the 2005 and 2008 winter wheat seasons, aphids were surveyed in the beginning of each planting season in several wheat plots in Alabama and western Florida. Collected aphids were identified and bioassayed for their yellow dwarf virus infectivity. This survey program was designed to identify the aphid species that serve as fall vectors of yellow dwarf virus into winter wheat plantings. From 2005 to 2008, bird cherry-oat aphid, Rhopalosiphum padi (L.); rice root aphid, Rhopalosiphum rufiabdominale (Sasaki); and greenbug, Schizaphis graminum (Rondani), were found consistently between October and December. The species of aphids and their timing of appearance in wheat plots were consistent with flight data collected in North Alabama between 1996 and 1999. Both R. padi and R. rufiabdominale were found to carry and transmit Barley yellow dwarf virus-PAV and Cereal yellow dwarf virus-RPV. The number of collected aphids and proportion of viruliferous aphids were low. Although this study has shown that both aphids are involved with introduction of yellow dwarf virus to winter wheat in Alabama and western Florida, no conclusions can be made as to which species may be the most important vector of yellow dwarf virus in the region.

South Africa currently exports fresh citrus (Citrus spp.) fruit to Japan using an in-transit cold treatment protocol of 14 d or 12 d at temperatures <0°C for treatment of Ceratitis capitata (Wiedemann) (Diptera: Tephritidae) in ‘Clementine’ mandarins (Citrus reticulata Blanco) and other citrus types, respectively. To reduce the risk of chilling injury with this treatment, research was conducted with temperatures >0°C. Earlier South African research had shown that young (6-d-old) larvae were slightly more tolerant of cold treatment and that there were no significant differences between cold tolerance of these larvae in different citrus types [oranges, Citrus sinensis (L.) Osbeck; grapefruits, Citrus paradisi Macfad.; lemons, Citrus limon (L.) Burm.f; and mandarins). Due to their ready availability, ‘Valencia’ oranges were used in this study. When 62,492 larvae in total were treated in three replicates at a mean temperature of 1.5°C for 16 d, there were three larval survivors. The trial was therefore repeated with oranges using a 16-d period at a mean temperature of 1.0°C and a mean of 1.4°C for the hourly maximum probe readings. Three replicates were again conducted and the resultant mean mortality in the control was 8.1% of 21,801 larvae, whereas the cold treatment mortality was 100% of 71,756 larvae. This treatment at a mean temperature of 1°C exceeded the Japanese confidence level requirement and also exceeded the Probit-9 mortality level, but not at a confidence level of 95%. These data support the establishment of a treatment protocol of 16 d at temperatures <1.4°C, commencing once all fruit pulp probes reach a temperature of 1°C or lower.

To develop a cold disinfestation treatment for the fruit fly Bactrocera invadens Drew, Tsuruta & White (Diptera: Tephritidae) that is rapidly spreading across Africa, research was conducted in Nairobi, Kenya, using flies from a laboratory culture and ‘Valencia’ orange (Citrus sinensis L. Osbeck) as the host. The developmental rate of B. invadens in Valencia oranges was determined at 28°C, and the third instar was found to be the least susceptible of the egg and larval life stages to cold treatment at 1.1°C in oranges. When 22,449 B. invadens third instars were exposed in oranges to a cold treatment with an approximate midpoint of 1.1 ± 0.5°C, the results suggested that a period of 16 d would be worthwhile verifying on a larger scale in oranges. Results from the first replicate of 16,617 larvae showed no survivors, but the second replicate of 23,536 larvae had three survivors. Because a longer cold treatment based on a mean temperature of 1.1°C would create logistical difficulties for some export markets, further replicates were conducted at an approximate midpoint of 0.5°C and at mean hourly maximum of 0.9 ± 0.5°C, for 16 d. After three replicates, in which 65,752 B. invadens third instars in total were treated with no survivors, the Japanese requirement of 99.99% mortality at the 95% confidence level was surpassed. The following treatment protocol for B. invadens larvae in oranges can therefore be recommended: fruit pulp to be maintained at temperatures of 0.9°C or lower for 16 consecutive days.

After the reduction in the use of broad-spectrum insecticides, Adelphocoris suturalis (Hemiptera: Miridae) has become an important pest of transgenic cotton, Gossypium hirsutum L., in China. A. suturalis is a highly mobile insect, moving rapidly in and out of crop fields, and traps baited with sex pheromones may be useful in monitoring and controlling its numbers. However, little is currently known regarding the chemical communication based on sex pheromones by this species. To use the synthesized sex pheromone effectively as part of the integrated pest management, some fundamental biological parameters under which the pheromone is produced must be understood. In this study, attractiveness of adult females or males of A. suturalis to conspecific individuals was examined by Y-tube bioassay; we also investigated the female sexually mature age and circadian rhythm of male attraction to females of A. suturalis in the field in 2008 and 2010. Y-tube bioassay results indicated that only males were attracted to odors from sexually mature virgin females. Two-year field trapping experiments showed that 4–18-d-old virgin females effectively attracted males, and males were attracted to virgin females during the scotophase, with a peak between 1900 and 2300 hours. These results improve our understanding of the sexual communication behavior of A. suturalis and provide evidence of female-produced sex pheromone in this species.

An attractant for Mexican fruit fly, Anastrepha ludens (Loew) (Diptera: Tephritidae), was developed from a commercial product called Sabor Uva containing processed Concord grape juice. The principal volatile components of Sabor Uva aroma were identified and an aqueous mixture of 15 components that was gas chromatographically similar to Sabor Uva was prepared. This mixture was equivalent to Sabor Uva in attractiveness by using wind-tunnel bioassays. After deleting chemicals that did not contribute to attractiveness, and increasing the concentrations of the remaining chemicals, the final attractant contained propylene glycol (90,000 ppm, vol/vol), acetic acid (4,500), methyl anthranilate (1,800), ethyl 2-methylpropionate (670), and one or both of the esters ethyl 3-methylbutyrate (44) and 2-methylbutyl propionate (44), in aqueous solution. This mixture was ≈1.8× as attractive as Sabor Uva by indirect comparison. Deletion of propylene glycol, acetic acid, methyl anthranilate, or ethyl 2-methylpropionate from the mixture significantly decreased attractiveness. Deletion of either of the other two esters seemed to diminish attractiveness although effects were not statistically significant. Deletion of water from the mixture significantly decreased attractiveness. We conclude that propylene glycol, acetic acid, methyl anthranilate, water, and at least one or as many as all three of the methyl-branched esters are essential for complete attractiveness.

This study examined whether economically important fruit fly species Anastrepha ludens (Loew), Anastrepha serpentina (Wiedemann), and Anastrepha obliqua (Macquart) (Diptera: Tephritidae) may opportunistically exploit guavas, Psidium guajava L. (Myrtaceae), growing near preferred natural hosts. We collected 3,459 kg of guavas and 895 kg of other known host species [sour orange, Citrus aurantium L.; grapefruit, Citrus paradisi Macfadyen; mango, Mangifera indica L.; white sapote, Casimiroa edulis La Llave and Lex.; sapote, Pouteria sapota (Jacq.); sapodilla, Manilkara zapota L.; and wild plum, Spondias purpurea L. and Spondias mombin L.] along an altitudinal gradient over a 4-yr period (2006–2009). Plants were growing in sympatry in 23 localities where the guavas are usually infested in the state of Veracruz, México. The guava samples yielded 20,341 Anastrepha spp. pupae in total (overall mean, 5.88 pupae per kg of fruit). Confirming previous reports, Anastrepha fraterculus (Wiedemann) and Anastrepha striata (Schiner) were found heavily infesting guavas in Veracruz. Importantly, although we did not find evidence that A. ludens and A. serpentina are able to attack this valuable commodity, we document for the first time in the agriculturally important state of Veracruz that P. guajava is an alternative natural host plant of A. obliqua. We recovered two fruit in the mango-growing locality of la Víbora, Tlalixcoyan, that harbored larvae of A. striata and A. obliqua. This finding has important practical implications for management of A. obliqua. Over the entire altitudinal gradient, when individual fruit infestation was examined, a dynamic pattern of species dominance was unveiled with guavas growing below 800 m above sea level mainly attacked by A. striata and a progressive replacement with increasing altitude by A. fraterculus. Interestingly, most individual fruit examined (97%) harbored a single species of fruit fly, a finding that may be taken as evidence of competitive displacement among sympatric species of fruit flies. Based on this study and previously published work by us on this topic, we conclude that literature reports indicating that A. ludens and A. serpentina infest guavas under field conditions should be questioned.

The chemical constituents of some essential oils extracted from aromatic plants (savory, Satureja thymbra L.; Turkish oregano, Origanum onites L.; myrtle, Myrtus communis L.; marjoram, Origanum majorana L.; laurel, Laurus nobilis L.; lemon, Citrus limon L.; sticky goosefoot, Chenopodium botrysh L.; and tansy, Tanecetum armenum [DC] Suchultz Bip.) were analyzed by gas chromatographymass spectrometry. Fumigant toxicity of volatile compounds was tested against Mediterranean flour moth, Ephestia kuehniella (Zeller) (Lepidoptera: Pyralidae), eggs and adults. Percentage of mortality and longevity of E. kuehniella adults were estimated after essential oil treatments. LC₅₀ and LC₉₉ values were determined for each exposure time for each essential oil. Marjoram and lemon oils were the most effective of all the essential oils tested. The major components were linalool, 1.8-cineole, citral, 2-(4a.8-dimethyl-1.2.3.4.4a.5.6.7-octahydro-naphthalen-2-yl)-prop-2-en-l-ol, and p-cymene for marjoram, laurel, lemon, goosefoot, and tansy, respectively. The LC₅₀ and LC₉₉ values were estimated as 3.27 and 5.13 µl liter^-1 air for marjoram and 4.05 and 5.57 µl liter^-1 air for lemon essential oils at the longest exposure time. Decreasing longevity effect of marjoram and lemon was more prominent compared with other essential oils. We suggest that essential oils obtained from certain aromatic plants have potential as fumigants for stored product pests.

The essential oil of Deverra scoparia Coss. & Durieu was investigated for its acaricidal activity against the worldwide pest twospotted spider mite, Tetranychus urticae Koch (Acari: Tetranychidae). The essential oil was analyzed by fast gas chromatography (GC) and GC-mass spectrometry. The activities of its individual and blended constituents were determined. Our study showed that female mortality increased with increasing D. scoparia oil concentrations, with LD₅₀ and LD₉₀ values at 1.79 and 3.2 mg liter^-1, respectively. A reduction in fecundity had already been observed for concentrations of 0.064, 0.08, and 0.26 mg liter^-1 D. scoparia essential oil. Ten major components, comprising 98.52% of the total weight, were identified; α-pinene was the most abundant constituent (31.95%) followed by sabinene (17.24%) and Δ3-carene (16.85%). The 10 major constituents of D. scoparia oil were individually tested against T. urticae females. The most potent toxicity was found with a-pinene, Δ3-carene, and terpinen-4-ol. The presence of all constituents together in the artificial mixture caused a significant decrease in the number of eggs laid by females, at 0.26 mg liter^-1 (11 eggs), compared with the control (50 eggs). The toxicity of blends of selected constituents indicated that the presence of all constituents was necessary to reproduce the toxicity level of the natural oil.

The long-term effects of methoxyfenozide on the longevity and reproductive processes of beet armyworm, Spodoptera exigua (Hübner) (Lepidoptera: Noctuidae), adults were assessed after exposure by ingestion. Methoxyfenozide significantly reduced adult male longevity compared with females by 1.1 and 1.5 d at 75 and 150 mg (AI) /liter, respectively. Fecundity decreased by >60% with both concentrations at 72 and 96 h after treatment, but at 48 h, no significant effect was observed. The carbohydrate, protein, and lipid content in the eggs were determined as representatives of the biochemical effects of methoxyfenozide associated with the disruption of reproductive processes. The content of carbohydrates in the eggs laid 48 h at treatment was similar to that of controls, but it increased by ≈1.5 and 2-fold in eggs laid after 72 and 96 h, respectively, compared with controls (15 µ g per egg). Protein content was reduced ′2.5 and ′3-fold for each treatment concentration, respectively, compared with the controls (25 and 23 µg per egg for 75 and 150 mg [AI] /liter, respectively) in eggs collected 72 and 96 h after treatment. Lipid content significantly decreased by ≈1.6-fold in both treatment concentrations in eggs collected at 48 and 96 h after treatment compared with the controls (24 and 21 µg per egg for 48 and 96, respectively), but it was similar to controls (=19 µg per egg) at 72 h (≈15 µg per egg) for both concentrations. The biochemical effects of methoxyfenozide on S. exigua egg formation detected in this work are consistent with the reduction in fertility observed, as reported previously.

Neotephritis finalis (Loew) (Diptera: Tephritidae), and sunflower bud moth, Suleima helianthana (Riley) (Lepidoptera: Tortricidae) are major head-infesting insect pests of cultivated sunflower (Helianthus annuus L.). Planting date was evaluated as a cultural pest management strategy for control of N. finalis and S. helianthana in several production regions of North Dakota during 2009 and 2010. Results of the nine site-year study revealed that late planting date (early to mid-June) reduced damage ratings and percentage of damaged heads for N. finalis compared with early planting dates (mid- to late May). Visual observations of adult N. finalis found that the majority of flies were found in the early planted sunflower (78.2%) compared with the late planted sunflower (21.8%). Late planting date also reduced the percentage of S. helianthana damaged heads compared with early planting dates. Yield losses were reduced with late planting date when populations of N. finalis and S. helianthana were high enough to cause damage. Results of this study showed that delayed planting is an effective integrated pest management strategy that can reduce head damage caused by N. finalis and S. helianthana and mitigate yield losses.

In 2006, we examined the flight responses of 43 species of longhorn beetles (Coleoptera: Cerambycidae) to multiple-funnel traps baited with binary lure blends of 1) ipsenol ipsdienol, 2) ethanol α-pinene, and a quaternary lure blend of 3) ipsenol ipsdienol ethanol α-pinene in the southeastern United States. In addition, we monitored responses of Buprestidae, Elateridae, and Curculionidae commonly associated with pine longhorn beetles. Field trials were conducted in mature pine (Pinus pp.) stands in Florida, Georgia, Louisiana, and Virginia. The following species preferred traps baited with the quaternary blend over those baited with ethanol α-pinene: Acanthocinus nodosus (F.), Acanthocinus obsoletus (Olivier), Astylopsis arcuata (LeConte), Astylopsis sexguttata (Say), Monochamus scutellatus (Say), Monochamus titillator (F.) complex, Rhagium inquisitor (L.) (Cerambycidae), Buprestis consularis Gory, Buprestis lineata F. (Buprestidae), Ips avulsus (Eichhoff), Ips calligraphus (Germar), Ips grandicollis (Eichhoff), Orthotomicus caelatus (Eichhoff), and Gnathotrichus materiarus (Fitch) (Curculionidae). The addition of ipsenol and ipsdienol had no effect on catches of 17 other species of bark and wood boring beetles in traps baited with ethanol and α-pinene. Ethanol α-pinene interrupted the attraction of Ips avulsus, I. grandicollis, and Pityophthorus Eichhoff spp. (but not I. calligraphus) (Curculionidae) to traps baited with ipsenol ipsdienol. Our results support the use of traps baited with a quaternary blend of ipsenol ipsdienol ethanol α-pinene for common saproxylic beetles in pine forests of the southeastern United States.

Survey and detection programs for native and exotic forest insects frequently rely on traps baited with odorants, which mediate the orientation of target taxa (e.g., the southern pine beetle, Dendroctonus frontalis Zimmermann) toward a resource (e.g., host material, mates). The influence of trap design on the capture efficiency of baited traps has received far less empirical attention than odorants, despite concerns that intercept traps currently used operationally have poor capture efficiencies for some target taxa (e.g., large woodborers). Several studies have recently demonstrated that treating traps with a surface lubricant to make them “slippery” can increase their capture efficiency; however, previously tested products can be expensive and their application time-consuming. The purpose of this study was to evaluate the effect of alternate, easier to apply aerosol lubricants on trap capture efficiency of selected forest insects. Aerosol formulations of Teflon and silicone lubricants increased both panel and multiple-funnel trap capture efficiencies. Multiple-funnel traps treated with either aerosol lubricant captured significantly more Monochamus spp. and Acanthocinus obsoletus (Olivier) than untreated traps. Similarly, treated panel traps captured significantly more Xylotrechus sagittatus (Germar), Ips calligraphus (Germar), Pissodes nemorensis (Germar), Monochamus spp., A. obsoletus, Thanasimus dubius (F.), and Ibalia leucospoides (Hochenwarth) than untreated traps. This study demonstrates that treating multiple-funnel and panel traps with an aerosol dry film lubricant can increase their capture efficiencies for large woodborers (e.g., Cerambycidae) as well as bark beetles, a weevil, a woodwasp parasitoid and a bark beetle natural enemy (Coleoptera: Cleridae).

Traps baited with disparlure, the synthetic form of the gypsy moth, Lymantria dispar (L.) (Lepidoptera: Lymantriidae), sex pheromone are used to detect newly founded populations and estimate population density across the United States. The lures used in trapping devices are exposed to field conditions with varying climates, which can affect the rate of disparlure release. We evaluated the release rate of disparlure from delta traps baited with disparlure string dispenser from 1 to 3 yr across a broad geographic gradient, from northern Minnesota to southern North Carolina. Traps were deployed over ≈12 wk that coincided with the period of male moth flight and the deployment schedule of traps under gypsy moth management programs. We measured a uniform rate of release across all locations when considered over the accumulation of degree-days; however, due to differences in degree-day accumulation across locations, there were significant differences in release rates over time among locations. The initial lure load seemed to be sufficient regardless of climate, although rapid release of the pheromone in warmer climates could affect trap efficacy in late season. Daily rates of release in colder climates, such as Minnesota and northern Wisconsin, may not be optimal in detection efforts. This work highlights the importance of local temperatures when deploying pheromone-baited traps for monitoring a species across a large and climatically diverse landscape.

Regeneration pests of loblolly pine (Pinus taeda L.) threaten growth and survival in intensively managed loblolly pine plantations throughout the southeastern United States. The Nantucket pine tip moth, Rhyacionia frustrana (Comstock), in particular, often reduces growth of loblolly pine but has been difficult to control with traditional insecticides due to multiple annual generations and multi-year infestations which are difficult to predict in timing and location. Relatively new systemic insecticide products offer a solution in that their efficacy persists through multiple generations and years after a single application. Efficacy of systemic imidacloprid and fipronil were evaluated side by side across multiple sites in Virginia. Significant reductions in Nantucket pine tip moth damage were noted in trees treated with either the imidacloprid or fipronil product compared with check trees. After 2 yr, growth improvement of treated trees relative to controls was modest and not significant at all sites, but per acre volume indices were significantly greater in treated blocks as a result of higher tree survival. Reduced seedling mortality was attributed primarily to prevention of damage by pales weevil, Hylobius pales Herbst (Coleoptera: Curculionidae), by both insecticide treatments. Control of pales weevil in addition to pine tip moth suggests that systemic insecticide products with a long window of efficacy might control additional nontargeted pests.

Three plusiine species, Autographa nigrisigna, Macdunnoughia confusa, and Thysanoplusia intermixta (Lepidoptera: Noctuidae), are commonly found together in lettuce, Lactuca sativa L., fields in Japan. Given the marked morphological similarities between these species and the difficulty associated with discriminating between them using only visual cues, we used multiplex polymerase chain reaction (PCR) assay to distinguish between the three target species. Multiplex PCR uses four primers to simultaneously amplify a specific region of the mitochondrial DNA and produce species-specific banding patterns. The stringency of the method was tested using specimens of different sex, location, and developmental stage, and consistent results were obtained for all samples. Indeed, our method has the potential to clarify the species structure of plusiine species in lettuce fields.

The developmental thresholds for Marmara gidosa Guillén & Davis (Lepidoptera: Gracillariidae) were investigated in the laboratory by using 17, 21, 25, 29, and 33°C. The lowest mortality occurred in cohorts exposed to 25 and 29°C. Other temperatures caused >10% mortality primarily in egg and first and second instar sap-feeding larvae. Linear regression analysis approximated the lower developmental threshold at 12.2°C. High mortality and slow developmental rate at 33°C indicate the upper developmental threshold is near this temperature. The degree-day (DD) model indicated that a generation requires an accumulation of 322 DD for development from egg to adult emergence. Average daily temperatures in the San Joaquin Valley could produce up to seven generations of M. gulosa per year. Field studies documented two, five, and three overlapping generations of M. gidosa in walnuts (Juglans regia L; Juglandaceae), pummelos (Citrus maxima (Burm.) Merr.; Rutaceae), and oranges (Citrus sinensis (L) Osbeck; Rutaceae), for a total of seven observed peelminer generations. Degree-day units between generations averaged 375 DD for larvae infesting walnut twigs; however, availability of green wood probably affected timing of infestations. Degree-day units between larval generations averaged 322 for pummelos and 309 for oranges, confirming the laboratory estimation. First infestation of citrus occurred in June in pummelo fruit and August in orange fruit when fruit neared 60 mm in diameter. Fruit size and degree-day units could be used as management tools to more precisely time insecticide treatments to target the egg stage and prevent rind damage to citrus. Degree-day units also could be used to more precisely time natural enemy releases to target larval instars that are preferred for oviposition.

The bitter plant-derived compounds cucurbitacins are known to stimulate feeding of adult cucumber beetles (Coleoptera: Chrysomelidae). A cucurbitacin-based gustatory stimulant applied as a flowable bait combined with either spinosad or carbaryl was compared with foliar sprays of spinosad and carbaryl for controlling two cucumber beetle species (Diabrotica undecimpunctata undecimpunctata Mannerheim and Acalymma trivittatum Mannerheim) in honeydew melons (Cucumis melo L.). Field studies were conducted on the University of California—Davis plant pathology farm in 2008 and 2009. Beetle densities after applications and fruit damage from beetle feeding were compared among treatments. In addition, beetle survival was compared within field cages placed over the treated foliage infested with beetles. Using all three measures of efficacy, we determined that the addition of cucurbitacin bait had no effect on the level of cucumber beetle control with carbaryl in either 2008 or 2009. In both years, spinosad did not significantly reduce cucumber beetle densities in either field cages or field plots and did not reduce fruit damage relative to the untreated control. The addition of the bait to spinosad did not improve its efficacy. A laboratory bioassay of the spinosad formulation used in the field showed it had significant lethal effects on adults of both cucumber beetle species. Results indicated that the bait formulation used did not improve cucumber beetle control but may benefit from the addition of floral attractants or using a different type of cucurbitacin.

Light brown apple moth, Epiphyas postvittana (Walker) (Lepidoptera: Tortricidae), is the target of the sterile insect technique, but reduced moth fitness from irradiation lowers the effective overflooding ratio of sterile to wild moths. New measures of insect quality are being sought to improve field performance of irradiated insects, thus improving the cost effectiveness of this technique. Male pupae were irradiated at intervals between 0 and 300 Gy, and adult flight success was assessed in a wind tunnel equipped with flight track recording software. A dose response was evident with reduced successful search behaviors at higher irradiation doses. Irradiation at 250 Gy reduced arrival success to 49% of untreated controls, during 2-min assays. Mark—release—recapture of males irradiated at 250 Gy indicated reduced male moth recapture in hedgerows (75% of control values of 7.22% ± 1.20 [SEM] males recaptured) and in vineyards (78% of control values 10.5% ± 1.66% [SEM] recaptured). Males dispersed similar distances in both habitats, and overflooding ratios dropped off rapidly from the release point in both landscapes. Transects of traps with central releases proved to be an efficient method for measuring the quality of released males. Relative field performance of moths was greater than suggested by wind tunnel performance, which could be due to time differences between the two assays, two-minute wind tunnel tests compared with days in the field treatments. Release strategies involving ground releases should consider the effect of limited postrelease dispersal. Aerial release could solve this problem and warrants investigation.

The efficacy of combining insecticides with a microencapsulated formulation of ethyl (2E,4Z) -2,4-decadienoate (pear ester, PE-MEC) was evaluated in walnuts, Juglans regia L., for codling moth, Cydia pomonella (L.) (Lepidoptera: Tortricidae), and navel orangeworm, Amyelois transitella Walker (Lepidoptera, Pyralidae). Two types of studies were conducted to compare the use of insecticides with and without PE-MEC. In the first study, PE-MEC in combination with reduced rates of insecticides, including chlorpyrifos, phosmet, methoxyfenozide, and codling moth granulovirus were evaluated in single tree replicates. PE-MEC was tested at one to three rates (0.6, 1.8, and 4.4 g active ingredient ha^-1) with each insecticide. In the second study, seasonal programs including sprays of esfenvalerate, chlorpyrifos, and ethyl parathion at full rates were evaluated in replicated two ha blocks. Significant reductions in nut injury occurred in the single-tree trial with treatments of PE-MEC plus insecticide compared with the insecticides used alone against both pest species; except with methoxyfenozide for navel orangeworm. Similarly, nut injury in the large plots was significantly reduced with the addition of PE-MEC, except for navel orangeworm in one of the two studies. These results suggest that adding pear ester as a microencapsulated spray can improve the efficacy of a range of insecticides for two key pests and foster the development of integrated pest management tactics with reduced insecticide use in walnut.

Although potato leafhopper, Empoasca fabae (Harris) (Hemiptera: Cicadellidae), is highly polyphagous, classic host studies do not recognize grapevines (Vitis spp.), as suitable hosts. Recently, injury has been reported and reproduction documented within grape vineyards, suggesting a host expansion for the leafhopper. To document this apparent expansion in host use, we determined whether grape plants were suitable hosts for potato leafhopper reproduction, measured the consequence of feeding injury on gas exchange rates of grape leaves, and compared the susceptibility to feeding injury among cultivars. We found that potato leafhopper adults survived equally well on grape (Vitis vinifera L.), alfalfa (Medicago sativa L.), and fava bean (Vicia faba L.). The total number of offspring was greater on fava bean but did not differ between alfalfa and grape. Injury to grapevines was assessed by measuring gas exchange responses of leaves in field cages and in greenhouse tests. We found marginally significant declines in photosynthesis and transpiration rates in the field (9.6 and 13.2%, respectively), and much stronger effects in greenhouse tests (ranging between 22 and 52%). Our results verify that Vitis is a suitable host, and that potato leafhopper is capable of injuring its gas exchange physiology. We discuss possible explanations for the host expansion, and its potential to damage commercial grapevines.

Western flower thrips, Frankliniella occidentalis (Pergande) (Thysanoptera: Thripidae), is a major horticultural pest and an important vector of plant viruses in many parts of the world. Methods for assessing thrips population density for pest management decision support are often inaccurate or imprecise due to thrips' positive thigmotaxis, small size, and naturally aggregated populations. Two established methods, flower tapping and an alcohol wash, were compared with a novel method, plant desiccation coupled with passive trapping, using accuracy, precision and economic efficiency as comparative variables. Observed accuracy was statistically similar and low (37.8– 53.6%) for all three methods. Flower tapping was the least expensive method, in terms of person-hours, whereas the alcohol wash method was the most expensive. Precision, expressed by relative variation, depended on location within the greenhouse, location on greenhouse benches, and the sampling week, but it was generally highest for the flower tapping and desiccation methods. Economic efficiency, expressed by relative net precision, was highest for the flower tapping method and lowest for the alcohol wash method. Advantages and disadvantages are discussed for all three methods used. If relative density assessment methods such as these can all be assumed to accurately estimate a constant proportion of absolute density, then high precision becomes the methodological goal in terms of measuring insect population density, decision making for pest management, and pesticide efficacy assessments.

Distribution and importance of woolly whitefly (Aleurothrixus floccosus) (Maskell) (Hemiptera: Aleyrodidae), was studied in Ethiopia with an evaluation of treatments against it. Results showed that the pest is distributed in most citrus-growing parts of the country equally infesting all types of citrus crops. Only one pupal parasitoid, Amitus sp., was recorded at Melkaoba. During 2006–2007, eight treatments gave better control of woolly whitefly compared with the control: endod (Phytolacca dodecandra L'Herit) berry extract, white oil 80%, neem oil, omo detergent soap, band application of gasoline, cyhalothrin (karate) 5% EC, selecron (profenofos) 500 EC, and rimon (novaluron) 10 EC. Treatments were applied on 6–8 yr-old orange trees at Melkaoba and Nazareth. At Melkaoba, application of cyhalothrin, selecron, white oil, and Neem gave better control of woolly whitefly compared with the control. All the treatments resulted in a lower number of ants than the control. Ants disrupt biocontrol agents of honeydew-secreting pests, including woolly whiteflies. Mean infestation score was higher in the control than the rest of the treatments. Similarly, at Nazareth, woolly whitefly numbers were lower recorded on cyhalothrin-treated plants. However, the numbers of eggs were significantly higher in endod extract-sprayed plants than the control. All treatments controlled ants better than the control except endod. Infestation scores were lower on endod- and cyhalothrin-treated plants than the control. Mean number of adult woolly whiteflies and eggs were significantly higher on newly grown leaves than older leaves. In general, the number of live adult woolly whiteflies showed a decreasing trend at both sites after treatment applications compared with the control.

In Arizona, the subterranean termite Heterotermes aureus (Snyder) (Isoptera: Rhinotermitidae) is the most economically important termite pest. We report here the evaluation of several commercial and experimental monitoring stations to capture and monitor H. aureus. In total, 12 monitoring stations were evaluated over two study periods. In 2001–2002, the commercial monitors Firstline and Termicon did not capture any H. aureus, whereas Termitrol did not capture significantly more termites than these two monitors. In contrast, three experimental Arizona Research Monitoring Stations (ARMS)—ARMS-PINE, ARMS-ASH, and ARMS-BBT— captured significantly more termites than Firstline and Termicon, and ARMS-BBT captured termites significantly more frequently than the commercial monitors. Similarly in 2003, the commercial monitors Firstline and Defender did not capture any H. aureus, whereas Extera did not capture significantly more termites than these two monitors. However, four monitor designs including the three most successful ARMS in 2001–2002 captured significantly more termites than Firstline and Defender, and ARMS-ASH captured termites significantly more often than the commercial monitors. On-ground ARMS monitors in general captured significantly more termites than commercial in-ground stations.

Two field populations of Spodoptera exigua (Hübner) (Lepidoptera: Noctuidae) from Dera Ghazi Khan (D.G. Khan) and Multan, Pakistan, were tested for resistance to the 10 most commonly used insecticides in Pakistan by using a standard leaf disc bioassay on the F₁ progeny. For comparison, a susceptible strain was generated from the Multan strain, which displayed lower LC₅₀ values for most of the insecticides, by either mass rearing without exposure to insecticides or single-pair crosses against selected insecticides. The single-pair crosses generated a more susceptible strain than mass rearing. The D.G. Khan field strain was highly resistant to Cypermethrin, profenofos, spinosad, abamectin, and chlorpyrifos and moderately resistant to deltamethrin, indoxacarb, and methoxyfenozide compared with susceptible lab strain. The Multan strain was highly resistant to profenofos and indoxacarb. Both field populations were susceptible to emamectin benzoate and lufenuron. Rotating these two insecticides with others that show very low, low, or moderate levels of resistance and have different modes of action may be useful for the effective management of this pest.

Resistance to malathion has been reported in field populations of the Mediterranean fruit fly, Ceratitis capitata (Wiedemann) (Diptera: Tephritidae), in areas of Spain where an intensive use of this insecticide was maintained for several years. The main goal of this study was to determine whether resistance to malathion confers cross-resistance to different types of insecticides. Susceptibility bioassays showed that the malathion-resistant W-4Km strain (176-fold more resistant to malathion than the susceptible C strain) has moderate levels of cross-resistance (three- to 16-fold) to other organophosphates (trichlorphon, diazinon, phosmet and methyl-chlorpyrifos), the carbamate carbaryl, the pyrethroid lambda-cyhalothrin, and the benzoylphenylurea derivative lufenuron, whereas cross-resistance to spinosad was below two-fold. The W-4Km strain was selected with lambda-cyhalothrin to establish the lambda-cyhalothrin-resistant W-1Kλ strain (35-fold resistant to lambda-cyhalothrin). The synergistic activity of the esterase inhibitor DEF with lambda-cyhalothrin and the increase in esterase activity in the W-1Kλ strain suggests that esterases may be involved in the development of resistance to this insecticide. Our results showed that resistance to malathion may confer some degree of cross-resistance to insecticides currently approved for the control of Mediterranean fruit fly in citrus crops (lambda-cyhalothrin, lufenuron, and methyl-chlorpyrifos). Especially relevant is the case of lambda-cyhalothrin, because we have shown that resistance to this insecticide can rapidly evolve to levels that may compromise its effectiveness in the field.

Since the discovery of the soybean aphid, Aphis glycines Matsumura (Hemiptera: Aphididae), in North America in 2000, chemical control has been the most effective method to manage aphid outbreaks. Increased insecticide use in soybean raises the possibility of developing insecticide resistance in soybean aphid, and monitoring insecticide susceptibility is essential to maintain pesticide tools. We developed a simple and reliable aphid-dip bioassay by using a tea strainer that resulted in ≥90% survival in controls. Using this technique, we tested susceptibility of a greenhouse strain of soybean aphid that has never been exposed to insecticides, and field-collected aphid strains from two counties in Michigan. Aphid susceptibility was tested for five insecticides by dipping groups of five aphids in each insecticide dose for 10 s. After 48 h, aphids were classified as dead or alive, and counted. Aphids from all strains were highly susceptible to chlorpyrifos, λ-cyhalothrin, esfenvalerate, and dimethoate, with LC₅₀ and LC₉₀ values well below the recommended application rates. However, aphids showed less susceptibility after 48 h to neonicotinoid imidacloprid, with higher LC₉₀s and wider fiducial limits. This illustrated the potential limitation of using a 48-h assay to evaluate insecticides with longer-term, sublethal impacts. Nevertheless, this study made use of a simple aphid-dip method to test and compare insecticide susceptibility of soybean aphid. In the event of a field failure, the aphid populations involved can be tested in comparison to a susceptible greenhouse strain to determine the extent of resistance development.

Cross-resistance to two fipronil analogs, butene-fipronil and ethiprole, was detected in fipronil-resistant field populations and a resistant laboratory strain of the planthopper Nilaparvata lugens (Stål) (Hemiptera: Delphacidae), although the two analogs have not been used widely in rice-growing areas in China. The results showed that six field populations with 23.8–43.3-fold resistance to fipronil had reached a higher level of cross-resistance to ethiprole (resistance ratio [RR] = 47.1–100.9-fold) and had a minor level of cross-resistance (RR = 3.4–8.1-fold) to butene-fipronil. After 10 generations of selection, the RR to fipronil increased from 7.3-fold to 41.3-fold. At the same time, the insect increased cross-RR to ethiprole from 16.3-fold to 65.6-fold, whereas it had only minor increase in cross-resistance to butene-fipronil from 2.8-fold to 4.0-fold. These results confirmed that fipronil-resistant N. lugens could develop a higher level of cross-resistance to ethiprole, although it still maintained a lower level cross-resistance to butene-fipronil. Our data suggest that ethiprole is not a suitable alternative for controlling N. lugens, once the insect has developed a high level resistance to fipronil. Further investigation is necessary to understand the cross-resistance mechanisms in N. lugens.

A series of substituted aromatic amides by varying the chain length, substitution of methyl, methoxy, chloro, and fluoro groups at ortho-, meta-, and para-positions of the phenyl ring of N,N-diethyl-2-phenylacetamide were synthesized. Laboratory studies were carried out to observe the behavioral responses and repellent activity of these newly synthesized aromatic amides against Aedes aegypti (L.) mosquitoes. The deterrent activity of these synthetic amides against any vectors has not been reported previously. These aromatic amides were tested for their behavioral responses and compared with the well known insect repellents, namely, N,N-diethyl toluamide; N,N-diethyl phenylacetamide; and N,N-diethylbenzamide. Out of the 14 compounds synthesized, seven compounds were selected on the basis of those showing >75% of repellent response for the bioefficacy test on human volunteers. The potential use of lead compounds in personal protection management is discussed.

Worldwide, the developing industry of cucumbers (Cucumis sativus L.) grown in greenhouses is threatened by damage from sucking pests, especially aphids. Among these, the melon aphid, Aphis gossypii Glover (Hemiptera: Aphididae), is the most serious. We tested the effect of two cucumber cultivars (‘Royal’and‘Storm’) and three vermicompost concentrations (0 [control], 20, and 30%) in field soil on the development and fecundity rates of A. gossypii, by using a randomized complete block design with four replicates as a factorial experiment. The developmental times of nymphs reared on plants grown into the three vermicompost concentrations ranged from 5.5 (0%) to 8.7 (30%) d (on Storm) and from 4.3 (0%) to 7 (30%) d (on Royal). The developmental time of melon aphid's nymphs was greatest on plants grown in the culture medium with 30% vermicompost rate and least on plants reared in the soil without vermicompost. The intrinsic rate of natural increase (r_m) of A. gossypii ranged from 0.204 d^-1 on plants grown in the soil amended with 30% vermicompost rate (on Storm seedlings) to 0.458 d^-1 on plants grown in the soil without vermicompost (on Royal seedlings). Accordingly, our findings confirm that a combination of a low level of vermicompost and a partially resistant cucumber cultivar might play an important role in managing this aphid on cucumbers in greenhouses.

Phytohormones and fatty acids (FAs) play important roles in plant resistance to insects and pathogens. In this study, we investigated the similarities and differences in the accumulations of phytohormones and FAs in the resistant wheat (Triticum aestivum L.) ‘Molly’ and the nonhost rice (Oryza sativa L.) ‘Niponbare’ in responses to Hessian fly, Mayetiola destructor (Say) (Diptera: Cecidomyiidae), larval attacks. Using chemical ionization-gas-chromatography/mass spectrometry, we analyzed the concentrations of 13 phytohomones and FAs at the attack site of wheat and rice plants at 1, 6, 24, or 48 h after the initial attack. Hessian fly attack resulted in increases of salicylic acid (SA), 12-oxo-phytodienoic acid (OPDA), palmitic acid (FA16:0), but a decrease of abscisic acid in both wheat and rice plants. In addition, the accumulation of jasmonic acid (JA) increased, whereas the accumulation of cinnamic acid (CA) decreased in wheat plants, but no changes were observed in the accumulation of JA, and the accumulation of CA increased in rice plants after Hessian fly attack. However, the accumulations of benzoic acid, strearic acid (FA18:0), and oleic acid (FA18:1) increased in rice plants, but no changes were observed in wheat plants after Hessian fly attack. Hessian fly-induced changes were more rapid in wheat plants in comparison with those in rice plants. Our study suggests that SA and OPDA may be involved in resistance of wheat and rice plants to Hessian fly and that the R gene-mediated resistance responses are more rapid than nonhost resistance responses.

Resistance (R) genes have a proven record for protecting plants against biotic stress. A problem is parasite adaptation via Avirulence (Avr) mutations, which allows the parasite to colonize the R gene plant. Scientists hope to make R genes more durable by stacking them in a single cultivar. However, stacking assumes that R gene-mediated resistance has no fitness cost for the plant. We tested this assumption for wheat's resistance to Hessian fly, Mayetiola destructor (Say) (Diptera: Cecidomyiidae). Our study included ten plant fitness measures and four wheat genotypes, one susceptible, and three expressing either the H6, H9, or H13 resistance gene. Because R gene-mediated resistance has two components, we measured two types of costs: the cost of the constitutively-expressed H gene, which functions in plant surveillance, and the cost of the downstream induced responses, which were triggered by Hessian fly larvae rather than a chemical elicitor. For the constitutively expressed H gene, some measures indicated costs, but a greater number of measures indicated benefits of simply expressing the H gene. For the induced resistance, instead of costs, resistant plants showed benefits of being attacked. Resistant plants were more likely to survive attack than susceptible plants, and surviving resistant plants produced higher yield and quality. We discuss why resistance to the Hessian fly has little or no cost and propose that tolerance is important, with compensatory growth occurring after H gene-mediated resistance kills the larva. We end with a caution: Given that plants were given good growing conditions, fitness costs may be found under conditions of greater biotic or abiotic stress.

The majority of plant viruses are dependent on arthropod vectors for spread between plants. Wheat streak mosaic virus (family Potyviridae, genus Tritimovirus, WSMV) is transmitted by the wheat curl mite, Aceria tosichella Keifer, and this virus and vector cause extensive yield losses in most major wheat (Triticum aestivum L.)-growing regions of the world. Many cultivars in use are susceptible to this vector-virus complex, and yield losses of 10–99% have been documented, wheat curl mite resistance genes have been identified in goat grass, Aegilops tauschii (Coss) Schmal., and transferred to hexaploid wheat, but very few varieties contain effectively wheat curl mite resistance, due to virulent wheat curl mite populations. However, wheat curl mite resistance remains an effective strategy to reduce losses due to WSMV. The goal of our project was to identify the most effective, reproducible, and rapid method for assessing wheat curl mite resistance. We also wanted to determine whether mite resistance is affected by WSMV infection, because the pathogen and pest commonly occur together. Single and group wheat curl mite infestations produced similar amounts of leaf rolling and folding on wheat curl mite-susceptible wheat varieties that were independent of initial wheat curl mite infestation. This finding will allow accurate, efficient, large-scale screening of wheat germplasm for wheat curl mite resistance by infesting plants with sections of wheat leaf tissue containing mixed stages of wheat curl mite. The wheat curl mite-resistant breeding line ‘OK05312’ displayed antibiosis (reduced wheat curl mite population development). The effect of WSMV infection on wheat curl mite reproduction was genotype-dependent. Mite populations increased on infected wheat curl mite- and WSMV-susceptible plants compared with uninfected plants, but WSMV infection had no significant effect on wheat curl mite populations on resistant plants. OK05312 is a strong source of wheat curl mite resistance for wheat breeding programs.

Field experiments were conducted in 2007 and 2008 to evaluate heat treatment for disinfestations of empty concrete elevator silos. A Mobile Heat Treatment Unit was used to introduce heat into silos to attain target conditions of 50°C for at least 6 h. Ventilated plastic containers with a capacity of 100 g of wheat, Triticum aestivum L., held Rhyzopertha dominica (F.) (Coleoptera: Bostrichidae) and Tribolium castaneum (Herbst) (Coleoptera: Tenebrionidae). Polyvinyl chloride containers with a capacity of 300 g of wheat held adults of Liposcelis corrodens (Heymons) (Psocoptera: Liposcelididae) and Liposcelis decolor (Pearman), which were contained in 35-mm Petri dishes within the grain. Containers were fastened to a rope suspended from the top of the silo at depths of 0 m (just under the top manhole), 10 m, 20 m, and 30 m (silo floor). When the highest temperature achieved was ≈50°C for 6 h, parental mortality of R. dominica and T. castaneum, and both psocid species was 98–100%. Progeny production of R. dominica occurred when there was parental survival, but in general R. dominica seemed less impacted by the heat treatment than T. castaneum. There was 100% mortality of L. corrodens at all depths in the heat treatments but only 92.5% mortality for L. decolor, with most survivors located in the bioassay containers at the top of the silo. Results show wheat kernels may have an insulating effect and heat treatment might be more effective when used in conjunction with sanitation and cleaning procedures.

The mold mite Tyrophagus putrescentiae (Shrank) is a common pest of stored food products. Until recently, commodity and facility treatments have relied on acaricides and fumigants to control this mite. However, T. putrescentiae will cause infestations in areas where acaricide or fumigant use may be restricted, prohibited, or highly impractical. Because temperature is an essential factor that limits the survival of arthropod species, extreme temperatures can be exploited as an effective method of control. Making low-temperature treatments reliable requires better temperature-time mortality estimates for different stages of this mite. This was accomplished by exposing a representative culture (eggs, nymphs, and adults) of noncold-acclimated T. putrescentiae to subfreezing temperatures to determine their supercooling points (SCPs), lower lethal temperatures (LLTs) and lethal times (LTimes) at set temperatures. The results indicate that the adult and nymphal stages of T. putrescentiae are freeze intolerant; based on 95% CIs, the adult LLT₉₀ of -22.5°C is not significantly different from the SCP of -24.2°C and the nymphal LLT₉₀ of -28.7°C is not significantly different from the SCP of -26.5°C. The egg stage seems to be freeze tolerant, with an LLT₉₀ of -48.1°C, significantly colder by ≈ 13.5°C than its SCP of -35.6°C. The LTime demonstrates that 90% of all mite stages of T. putrescentiae can be controlled within commodity or packaged product by freezing to -18°C for 5 h. By achieving the recommended time and temperature exposures, freezing conditions can be an effective way of controlling mites and reducing chronic infestations.

The red flour beetle, Tribolium castaneum (Herbst) (Coleoptera: Tenebrionidae), is a major coleopteran pest in flour mills and storage facilities. An aggregation pheromone has been identified for this pest; however, the pheromone is of limited value for population monitoring. To develop more efficient methods to monitor this pest, experiments were conducted to determine whether light functioned as an attractant for the red flour beetle. Light-emitting diodes (LEDs) of various wavelengths were examined as light sources because they produce bright, narrow light spectra. A comparison of responses to light spectra across the visible and UV regions of the electromagnetic spectrum indicated that the beetle was most attracted to near UV LED at a 390 nm dominant wavelength. The use of LEDs in competitive laboratory experiments resulted in a 20% capture of released beetles, compared with a 1% capture with the aggregation pheromone alone. Even more beetles were captured with a combination of LEDs and commercially available chemical lures in traps. LEDs can easily be added onto existing trap designs or new traps can be designed to take full advantage of positive phototaxis.

We investigated the effects often constant temperatures (20.0, 22.5, 25.0, 27.5, 30.0, 32.5, 35.0, 37.5, 39.0, and 41.0°C) on the development, survival, and reproduction of the psocid Liposcelis yunnaniensis Li & Li (Psocoptera: Liposcelididae). At 39.0 and 41.0°C, none of individuals could develop successfully or reproduce. From 20 to 37.5°C, the development period from egg to adult ranged from 64.3 d at 20°C to 16.1 d at 35°C. The lower developmental threshold for egg, nymph, and combined immature stages were estimated at 15.08, 15.13, and 14.77°C, respectively. After emergence the females went through a preoviposition period that ranged from 18.5 d at 22.5°C to 3.11 d at 35°C, whereas it was 16.3 d at 20°C. Liposcelis yunnaniensis produced most eggs at 35°C and the fewest at 22.5°C. The population reared at 35°C had the highest intrinsic rate of increase, shorter mean generation time, and shortest population doubling time compared with other temperatures. According to Weibull frequency distribution, L. yunnaniensis reared at all the temperatures had type III survivorship curves (c < 1.0). Based on life-table parameter estimations, we suggest that optimum range of temperatures for this species is from 25 to 37.5°C. These data give us useful information on population biology of L. yunnaniensis and can be used to better manage this species.

The essential oils from rhizomes of Alpinia conchigera Griff, Zingiber zerumbet Smitt, Curcuma zedoaria (Berg.) Roscoe; their major compounds (camphene, camphor, 1,8-cineole, α-humulene, isoborneol, α-pinene, β-pinene and terpinen-4-ol); and synthetic essential oils comprised of mixtures of major pure compounds in the same ratios as the extracted essential oils were tested for contact, feeding reduction, and repellency against Sitophilus zeamais Motschulsky and Tribolium castaneum (Herbst) adults. Via topical applications, the three extracted oils had similar toxicity against S. zeamais (LD₅₀, fiducial limits: 18–24 µg oil/mg insect). T. castaneum had similar sensitivity to all three oils (35–58 µg/mg), and it was less sensitive than S. zeamais. The LD₅₀ values of synthetic A. conchigera and synthetic Z. zerumbet oils were similar to those of their corresponding extracted essential oils. The synthetic C. zedoaria oils showed lower contact toxicity than the extracted C. zedoaria oils to both insects. Sitophilus zeamais and T. castaneum were sensitive to terpinen-4-ol and isoborneol in contact toxicity tests. In antifeedant tests, the three extracted oils were able to decrease the consumption of flour disks, especially Z. zerumbet oils, whereas both insect species could feed on the flour disks treated with three synthetic essential oils. Only terpinen-4-ol deterred feeding in both insects. In repellency tests, A. conchigera oils at highest concentration repelled S. zeamais and T. castaneum. None of the synthetic essential oils repelled S. zeamais (315 µl/cm²) and T. castaneum (31 µl/cm²). Only terpinen-4-ol showed repellent activity against both insects.