We present a population model of the insect Scaphoideus titanus Ball, the leafhopper vector of Flavescence Dorée phytoplasma in Vitis vinifera L. The model accounted for the stage-dependent S. titanus life cycle rates and timing, and vineyard settings such as surface area, plant density, and sampling characteristics. The model parameters were estimated against 13 independent cases of population counting in both laboratory and field conditions, and returned a correlation coefficient in the range 86.4 to 99.1% with residuals in the range 3.5 to 26.3%. A statistical parametric analysis showed that the standard deviation of life cycle rates generally varied more than the one resulting from timing parameters. However, a stochastic sensitivity analysis showed that S. titanus dynamics were more susceptible to variations in timing than rate parameters. Analysis of scenarios of insecticide suppression efficiency and timing showed that S. titanus presence could be optimally controlled by a combination of suppression efficiency and timing. These results were instrumental to understand in which specific aspect of S. titanus life cycle could pest management operations be most effective to reduce S. titanus presence in vineyards, and possibly reduce the risk of Flavescence phytoplasma spread.

Simplification of agroecosystems because of industrialization of agriculture may cause the loss of associated animal biodiversity of both vertebrates and invertebrates. To measure how the agricultural intensification on coffee plantations affects ant biodiversity, we intensively sampled ants in Caldono (Cauca, Colombia). We surveyed 15 sites classified into three management types: sun coffee plantations, shaded coffee plantations, and forest patches. Fifteen 50-m linear transects, each one consisting of 5 pitfall traps and 5 tuna baits, were set at each sampling location between December of 2009 and February of 2010. We collected 18,186 ants that represent 82 ant species, 34 genera, and 9 subfamilies of Formicidae (Hymenoptera: Formicidae). The management intensification index showed an increasing intensification gradient along the 15 sampling locations from forest patches to shaded coffee to sun coffee plantations. Shaded coffee plantations harbored the highest number of species (60), followed by forest (56) and sun coffee (33). Ant species composition and plant structure on shaded coffee plantations resembled the forest patches more than the sun coffee plantations. Forest and shaded coffee plantations had a more equitable distribution of ant species, whereas in sun coffee plantations, Linepithema neotropicum (Emery) and Ectatomma ruidum (Roger) typically outnumbered all other ant species. Evidence from functional groups indicated that specific habitat and feeding requirements exist among the species that are found together. Our results confirmed that intensification of agriculture negatively affects ant diversity, despite the fact that farms were located in a heterogeneous landscape, suggesting that agroecological management is a strong determinant in the conservation of wild fauna.

Spiders are a very diverse group of invertebrate predators found in agroecosystems and natural systems. However, spider distribution, abundance, and eventually their ecological function in ecosystems can be influenced by abiotic and biotic factors such as agricultural intensification and dominant ants. Here we explore the influence of both agricultural intensification and the dominant arboreal ant Azteca instabilis on the spider community in coffee agroecosystems in southern Mexico. To measure the influence of the arboreal ant Azteca instabilis (F. Smith) on the spider community inhabiting the coffee layer of coffee agroecosystems, spiders were collected from coffee plants that were and were not patrolled by the ant in sites differing in agricultural intensification. For 2008, generalized linear mixed models showed that spider diversity was affected positively by agricultural intensification but not by the ant. However, results suggested that some spider species were associated with A. instabilis. Therefore, in 2009 we concentrated our research on the effect of A. instabilis on spider diversity and composition. For 2009, generalized linear mixed models show that spider richness and abundance per plant were significantly higher in the presence of A. instabilis. In addition, analyses of visual counts of insects and sticky traps data show that more resources were present in plants patrolled by the ant. The positive effect of A. instabilis on spiders seems to be caused by at least two mechanisms: high abundance of insects and protection against predators.

In this study we comprehensively assessed Collembola biodiversity at Three Gorges Area, one of most diverse habitat regions in China. In total, 3,796 Collembola specimens comprising 9 families, 45 genera, and 103 species (including 14 new species and new records in China) were collected from three primary sampling areas: one nature reserve and two rural and urban areas representing different degrees of human influence. Each sampling area was further divided into nine sampling sites associated with different habitats and altitudes. Analyses of biodiversity data showed that individual abundance was highest in the nature reserve followed by mildly human influenced areas, and then highly influenced areas, and species richness was lowest in highly influenced areas. Hence, we suggest Collembola biodiversity is systematically lost after urbanization. In the nature reserve, altitude significantly influenced both the species richness and individual abundance, whereas in rural and urban areas, both altitude and the human-altered environmental gradient were influential We also measured sampling efficiency and estimated potential species richness in these areas. This study serves as both a fundamental survey of Collembola biodiversity, as well as an assessment of human/environmental influence on the Collembola community, and can provide further insight into protecting the soil integrity of the Three Gorges Area.

Invasive common wasps (Vespula vulgaris L.) are predators of invertebrates in Nothofagus forests of New Zealand. We reduced wasp densities by poisoning in three sites over three y. We predicted an increase in the number of invertebrates and a change in the community composition in sites where wasps were poisoned (wasps removed) relative to nearby sites where wasps were not poisoned (wasps maintained). Wasp densities were significantly reduced by an average of 58.9% by poisoning. Despite this reduction in wasp densities, native bush ants (Prolasius advenus Forel) were the only taxa that was significantly influenced by wasp removal. However, contrary to our predictions there were more ants caught in pitfall traps where wasps were maintained. We believe that the higher abundance of these ants is probably because of the scarcity of honeydew in wasp-maintained sites and compensatory foraging by ants in these areas. Otherwise, our results indicated no significant effects of reduced wasp densities on the total number of invertebrates, or the number of invertebrate families, observed in pitfall or Malaise traps. An analysis of community composition (permutational multivariate analysis of variance) also indicated no significant difference between wasp-removed or wasp-maintained communities. The most parsimonious explanation for our results is that although we significantly reduced wasp numbers, we may not have reduced numbers sufficiently or for a sufficiently long period, to see a change or recovery in the community.

The interactions between the fruit fly Anastrepha spatulata Stone (Diptera: Tephritidae) and two species of moths, the gelechiid Coleotechnites sp. and an unidentified tortricid species, were examined on their effects on seed production in terms of their exploitation within fruits of Schoepfia schreberi J.F. Gmel (Santalales: Olacaceae). The study was carried out in three experimental sites during 3 yr. Under conditions of abundant fruit, A. spatulata was the dominant exploiter at the population level, as shown by its ability to infest the largest number of fruits of the three herbivores and substantially displace its moth competitors. In a separate experiment, when resource-partitioning species were excluded, A. spatulata infested twice as many fruits as the two moth species (44.3%). Field observations examined the ability of A. spatulata to locate suitable fruits. We found that, the variation in fruit characters influenced fruit suitability in relation to its size (4.1261 ± 0.0272 mm [mean ± SE]) and weight (0.0618 ± 0.0005 mg [mean ± SE]). Uninfested fruits produce viable seed but the interaction of all species (exploiting for the fruits) led to limited seed formation.

Endophytic fungi, which live within host plant tissues without causing any visible symptom of disease, are important mediators of plant-herbivore interactions. These endophytes enhance resistance of host plant against insect herbivores mainly by productions of various alkaloid based defensive compounds in the plant tissue or through alterations of plant nutritional quality. Two endophytic fungi, i.e., Nigrospora sp. and Cladosporium sp., were isolated from Tinospora cordifolia (Thunb.) Miers, a traditional indian medicinal plant. Cauliflower (Brassica oleracea L.) plants were inoculated with these two endophytic fungi. The effect of endophyte infected and uninfected cauliflower plants were measured on the survival and development of Spodoptera litura (Fab.), a polyphagous pest. Endophyte infected cauliflower plants showed resistance to S. litura in the form of significant increase in larval and pupal mortality in both the fungi. Inhibitory effects of endophytic fungi also were observed on adult emergence, longevity, reproductive potential, as well as hatchability of eggs. Thus, it is concluded that antibiosis to S. litura could be imparted by artificial inoculation of endophytes and this could be used to develop alternative ecologically safe control strategies.

Mutualism is a common and important ecological phenomenon characterized by beneficial interaction between two species. Red imported fire ants, Solenopsis invicta Buren, tend honeydew-producing hemipteran insects and reduce the activity of these insects’ enemies. Anthemipteran interactions frequently exert positive effects on the densities of hemipterans. We tested the hypothesis that ant tending can increase the densities of the mealybug, Phenacoccus solenopsis Tinsley (Hemiptera: Pseudococcidae), and reduce the densities of the mealybug's predatory and parasitic enemies, the lady beetle, Menochilus sexmaculata Fabricius (Coleoptera: Coccinellidae), and the parasitoid wasp, Aenasius bambawalei Hayat (Hymenoptera: Encyrtidae). We found that more ants foraged on mealybug-infested hibiscus plants than on mealybug-free plants. The number of foraging ants on plants infested with high densities of mealybugs (62.5 ants per plant) was nearly six times that on mealybug-free plants (10.2 ants per plant). Experiment results showed that ant tending significantly increased the survival of mealybugs: if predatory and parasitic enemies were present, the survival of mealybugs tended by fire ants was higher than that in the absence of tending ants. Furthermore, this tending by fire ants significantly decreased the survival of lady beetle larvae. However, no apparent effect was observed on the survival of parasitoid.

The pecan weevil, Curculio caryae (Horn), is a key pest of pecan, Carya illinoinensis (Wangenh.) K. Koch. Prior research indicated the potential for use of Hypocreales fungi to suppress C. caryae. We compared the efficacy of two fungal spp., Beauveria bassiana (GHA strain) and Metarhizium brunneum (F52), in their ability to cause C. caryae mortality. The fungus, B. bassiana, was applied to trunks of pecan trees (a method previously shown to be effective in C. caryae suppression) and efficacy was compared with M. brunneum applied to the ground or to the trunk with or without SoyScreen Oil as an ultraviolet protecting agent. Results indicated B. bassiana to be superior to M. brunneum regardless of application method; consequently, the potential for applying B. bassiana to control C. caryae was explored further. Specifically, the impact of different fertilizer regimes (as used by pecan growers) on the persistence of B. bassiana (GHA) in soil was determined. B. bassiana was applied to soil in a pecan orchard after one of several fertilizer treatments—i.e., ammonium nitrate, crimson clover, poultry litter, clover plus poultry litter, and a no-fertilizer control. B. bassiana persistence up to 49 d in 2009 and 2010 was assessed by plating soil onto selective media and determining the number of colony forming units, and by baiting soil with a susceptible host, Galleria mellonella (L.). Fertilizer treatments did not impact B. bassiana persistence. We conclude that standard fertilizers for nitrogen management, when applied according to recommended practices, are unlikely to negatively impact survival of B. bassiana in pecan orchards when the fungus is applied for C. caryae suppression during weevil emergence. Additional research on interactions between entomopathogenic fungi and fertilizer amendments (or other tree nutrition or soil management practices) is merited.

The application of a juvenile hormone analog, methoprene, to newly emerged adult males reduced the time required for sexual maturation and enhanced mating success in several species of tephritid fruit flies. In this work, we investigated the effect of topical methoprene application on West Indian fruit fly, Anastrepha obliqua (Macquart), male calling, mating, and volatile release. Males treated with topical methoprene exhibited sexual maturation and reproductive behavior 2 d earlier when compared with control males treated with acetone. Methoprene-treated males began calling and mating at 4 d old, whereas control males did not call and mate until 6 d old. The gas chromotographymass spectrometry analysis of volatiles showed that during calling A. obliqua males consistently released four compounds; three of them were identified as (Z)-3-nonenol, (Z,E)-α-farnesene, (E,E)α-farnesene, and a fourth compound with the appearance of a farnesene isomer. Both treated and control males released the same compounds, although treated males started to release volatiles before that control males. The results are discussed in view of possible methoprene application with the aim of reducing costs in fly emergence and release facilities before eventual release of A. obliqua in the field, thus improving the sterile insect technique.

After fire, the whitespotted sawyer, Monochamus scutellatus scutellatus (Say) (Coleoptera: Cerambycidae), is considered one of the most damaging xylophagous insects by forest industries in the eastern boreal forest of North America. Although this species is often considered opportunistic because it dwells on various stressed host trees, it can be found in very high abundance after forest fire and, consequently, it has been suspected of being a pyrophilous species or fireassociated species. The aim of this study was first to determine whether the whitespotted sawyer lays eggs preferentially on burned rather than unburned hosts, and second, to determine its preference between black spruce (Picea mariana [Mill] B.S.P.) and jack pine (Pinus banksiana Lamb.) for oviposition. Host suitability also was estimated to determine if whitespotted sawyer females make optimal choices to maximize offspring development. To determine host suitability, we used the abundance distribution of larval instars as a proxy of larval development quickness and we compared weight and head-capsule width of larvae of different larval instars as measures of insect growth in each type of log. Based on the frequency of oviposition behavior, females showed no preference for either burned or unburned black spruce logs, and both were equally suitable for larval development. Furthermore, females laid more eggs on black spruce than on jack pine, but host suitability was not statistically affected. Nevertheless, larvae had mostly reached the fourth instar on black spruce, whereas those on jack pine were mostly at the third instar, suggesting faster development on black spruce.

The black twig borer, Xylosandrus compactus (Eichhoff) (Coleoptera: Curculionidae: Scolytinae), is a serious pest of coffee (Coffea arabica L.) in the Kona region of the island of Hawaii, the center of the largest area of coffee production within the state of Hawaii. This study indirectly characterizes the spatial distribution of X. compactus in coffee plantations through assessment of twig borer damage, and presents a sequential sampling plan for monitoring X. compactus population densities. Taylor's Power Law (TPL) and Iwao's mean crowding index showed that X. compactus infestations were highly aggregated within plantations, with b and ß values significantly larger than 1. The TPL linear regression of log variance against log mean (R² = 0.92) provided a better fit to the data than the linear regression of mean crowding on the mean (R² = 0.68). Subsequently, Taylor's power law parameters were used to develop the Green's sequential plan to estimate densities of X. compactus at the 90 and 75% precision levels.

McPhail-type traps baited with ammonium acetate and putrescine were used to monitor populations of Anastrepha obliqua (Macquart) and Anastrepha suspensa (Loew) in two orchards with hosts of these flies (mango, Mangifera indica L., and carambola, Averrhoa carambola L.), as well as in forest fragments bordering these orchards. Contour maps were constructed to measure population distributions in and around orchards. Our results indicate that Anastrepha populations are focused around host fruit in both space and time, that traps do not draw fruit flies away from hosts, even when placed within 15 m of the host, and that lures continue to function for 6 mo in the field. The contour mapping analyses reveal that populations of fruit flies are focused around ovipositional hosts. Although the trapping system does not have a very long effective sampling range, it is ideal, when used in combination with contour analyses, for assessing fine-scale (on the order of meters) population distributions, including identifying resources around which fly populations are focused or, conversely, assessing the effectiveness of management tools. The results are discussed as they pertain to monitoring and detecting Anastrepha spp. with the McPhail-type trap and ammonium acetate and putrescine baiting system and the dispersal of these flies within Puerto Rico.

Cover crop mulch and weeds create habitat complexity in agricultural fields that may influence arthropods. Under strip-tillage systems, planting rows are tilled and preestablished cover crops can remain between rows. In field experiments conducted in Michigan in 2010 and 2011, a preestablished oat (Avena sativa L.) cover crop was allowed to grow between rows of strip-tilled cabbage and killed at 0, 9–14, or 21–27 d after transplanting (DAT). The effects of herbicide intensity and oat kill date on arthropods, weeds, and crop yield were examined. Two levels of herbicide intensity (low or high) were used to manipulate habitat vegetational complexity, with low weed management intensity resulting in more weeds, particularly in 2010. Oat kill date manipulated the amount of cover crop mulch on the soil surface. Later oat kill dates were associated with higher natural enemy abundance. Reduced herbicide intensity was associated with 1) lower abundance of several key cabbage (Brassica oleraceae L.) pests, and 2) greater abundance of important natural enemy species. Habitats with both later oat kill dates and reduced herbicide intensity contained 1) fewer herbivores with chewing feeding guilds and more specialized diet breadths, and 2) greater abundance of active hunting natural enemies. Oats reduced cabbage yield when oat kill was delayed past 9–14 DAT. Yields were reduced under low herbicide intensity treatments in 2010 when weed pressure was greatest. We suspect that increased habitat complexity associated with oat mulches and reduced herbicide intensity enhances biological control in cabbage, although caution should be taken to avoid reducing yields or enhancing hyperparasitism.

Damage to apple (Malus domestica Borkhausen) by Campylomma verbasci (Meyer), has occurred even when effective insecticides are applied against nymphs present at the petal fall stage. However, insecticide application at pink bud prevents damage more effectively than when the same insecticides are applied at petal fall. We tested the hypothesis that most mullein bug damage occurs between bloom and petal fall by using two approaches. In the first, we caged naturally occurring nymphs on ‘Red Delicious’ limbs and restricted their possible infestation timing by applying insecticides both before cages were placed and also through the cage at various crop stages from bloom through fruit set. In a second approach, we caged Red Delicious and ‘McIntosh’ fruit clusters and introduced either small or large nymphs at various times from bloom through 3 wk after fruit set. Fruit damage on both varieties was greatest when small nymphs were introduced between bloom and petal fall; damage was uncommon from small nymphs introduced after fruit were ≈6 mm, and absent after the 13 mm size. However, damage was greater in cages into which large nymphs were introduced at 10–13 mm, than in untreated control cages. Fruit damage levels were equivalent on McIntosh and Red Delicious. We compared emergence of nymphs from McIntosh shoots with adjacent plantings of other, more susceptible cultivars by forcing hatch in the laboratory from cuttings collected in late winter. Significantly more nymphs hatched from susceptible varieties than from McIntosh, suggesting possible differences in levels of oviposition.

The monoterpenoid citral synergized the electroantennogram (EAG) response of male Grapholita molesta (Busck) antennae to its main pheromone compound Z8–12:OAc. The response to a 10-µg pheromone stimulus increased by 32, 45, 54, 71 and 94% with the addition of 0.1, 1, 10, 100 and 1,000 µg of citral, respectively. There was no detectable response to 0.1, 1, or 10 µg of citral; the response to 100 and 1,000 µg of citral was 31 and 79% of the response to 10 µg of Z8–12:OAc. In a flight tunnel, citral affected the mate-seeking behavior of males. There was a 66% reduction in the number of males orientating by flight to a virgin calling female when citral was emitted at 1,000 ng/min ≈1 cm downwind from a female. Pheromone and citral induced sensory adaptation in male antennae, but citral did not synergize the effect of pheromone. The exposure of antennae to 1 ng Z8–12:OAc/m³ air, 1 ng citral/m³ air, 1 ng Z8–12:OAc 1 ng citral/m³ air, or to 1 ng Z8–12:OAc 100 ng citral/m³ air for 15 min resulted in a similar reduction in EAG response of 47–63%. The exposure of males to these same treatments for 15 min had no effect on their ability to orientate to a virgin calling female in a flight tunnel. The potential for using citral to control G. molesta by mating disruption is discussed.

Jeffrey pine, Pinusjeffreyi Greville and Balfour, is a dominant yellow pine and important overstory component of forests growing on diverse sites from southwestern Oregon to Baja California to western Nevada. The Jeffrey pine beetle, Dendroctonus jeffreyi Hopkins (Coleoptera: Curculionidae: Scolytinae), is monophagous on Jeffrey pine and its primary insect pest. Despite the importance of P. jeffreyi, difficult terrain, environmental concerns, and lack of roads can constrain pest management activities. Semiochemicals are often easier to apply and more environmentally acceptable than other options, but they are lacking in this system. Attractants have been identified, but field bioassays have been limited because of infrequent or short duration outbreaks and a lack of beetles during nonoutbreak periods. Disruptant semiochemicals have not been assessed for D. jeffreyi during outbreak conditions; however, commercially available semiochemicals have been implicated as disruptants for this bark beetle. The objective of this study was to identify the most effective commercially available attractant and disruptant semiochemicals for D. jeffreyi. Our highest observed catch occurred with the blend of 5% 1-heptanol and 95% n-heptane. When this was used to challenge potential disruptant semiochemicals, the combination of S-(-)-verbenone and the green leaf volatile blend (cis-3-Hexenol and 1-Hexanol) reduced trap catch by ≈80%. However, frontalin was most effective, reducing the number of D. jeffreyi caught by >96%. Within each year of the study, the percentage female of D. jeffreyi caught with our attractant decreased from start to end of the experimental period. On average, our first collection in a year (mid-June to early July) was 59% female, whereas our last (mid-August) was 34%. Frontalin was equally or more effective against females (the pioneering sex) than males, providing optimism that semiochemical disruption may be possible for protecting Jeffrey pines from D. jeffreyi.

Redbay ambrosia beetle, Xyleborus glabratus Eichoff, is an exotic species to North America vectoring a deadly vascular wilt disease of redbay [Persea borbonia (L.) Spreng], swampbay [P. palustris (Raf.) Sarg.], avocado (P. americana Mill.), and sassafras [Sassafras albidum (Nutt.) Nees]. Xyleborus glabratus is attracted to manuka oil lures, which are commercially available, and phoebe oil. Variable efficacy of manuka oil lures and insufficient availability of phoebe oil prompted us to investigate the reasons behind changes in manuka oil lure efficacy and to test cubeb oil, a readily available essential oil from Piper cubeba L. seeds, as an alternative attractant. Attraction, release rates and durations, and volatile composition of manuka oil lures manufactured in 2008 were compared with manuka oil lures manufactured in 2012, and to whole and a distilled fraction of cubeb oil. Manuka oil lures from 2008 were more attractive to X. glabratus than controls for 8 wk, whereas lures from 2012 were attractive for only 2 wk. Cubeb oil and the distilled fraction of it were as attractive as or more attractive than manuka oil in three trials. In gravimetric studies, manuka oil lures from 2008 and cubeb oil lures continued to release volatiles for 57 d, whereas lures from 2012 stopped after 16 d. The chemical composition of volatiles released from new manuka oil lures from 2008 was similar to 2012; however, a preservative (butylated hydroxytoluene) was detected in the 2008 lures. Cubeb oil was an effective attractant for X. glabratus that lasted 8–9 wk when released from bubble lures.

Lady beetles such as Coleomegilla maculata DeGeer and Hippodamia convergens Guerin-Meneville have been categorized as income breeders because egg maturation depends on resources available during reproduction. However, capital resources acquired during larval feeding influence reproductive success via effects on adult body size and other traits. We produced three sizes of beetles by varying larval access to food and subjected mated females to alternating periods of food surplus and deficit. Both species exhibited temporal variation in clutch size that reflected changes in income, the amplitude of fluctuations being greater in H. convergens. Egg mass in C. maculata appeared to increase as a fixed function of oviposition sequence but also was affected by maternal body size, whereas H. convergens egg mass fluctuated more in response to food supply. Fertility was largely unaffected by income fluctuation but appeared constrained by capital, especially in H. convergens. Dynamic changes in reproductive effort (daily mass of eggs/female mass at emergence) mirrored changes in clutch size, the amplitude of fluctuations being greater in H. convergens, the species with higher reproductive effort. Generally, large females compensated for income fluctuations better than small females, likely because of their greater capital and possibly an ability to consume larger meals when food was available. The greater sensitivity to income observed in H. convergens likely reflects a higher degree of aphid-specificity compared with the more generalist C. maculata because effective exploitation of ephemeral aphid outbreaks would favor rapid reproductive responses to changes in food supply.

The life cycle of Lethocerus deyrollei (Vuillefroy) in Sayo-cho, Hyogo, Japan (35 °00′ N, 134 °21′ E), was studied in terms of flight, reproduction, and energy allocation as well as developmental zero (t₀) and required heat units (K) for a generation. Counts of bugs attracted to electric lighting showed that L. deyrollei flew most frequently in July, the second half of the mating season. The weight of flight muscle showed no significant yearly change despite a conspicuous difference in the flight activities. Fat content in the abdomen was low during summer, when oviposition activity reached a high level in females. Thereafter, lipid accumulation increased to mid-October when flight to an overwintering site took place. The lipid reservoir in late summer may be critical for surviving winter but no significant decrease was observed during overwintering. The number of eggs in the ovary indicated univoltism because no females had mature eggs late in the year. t₀ and K were calculated based on laboratory rearing at different temperatures. Thus, estimated K (635 degree days) and local heat mass suggest a univoltine life cycle in Sayo-cho. The possible areas for successful inoculation of L. deyrollei were examined on the basis of available heat mass and day length in places where the species is extinct or not observed. Based on the estimated K and critical day length for reproductive maturation, Niigata and Tokyo fulfill suitable conditions of the Sayo population to complete a univoltine life cycle.

The emerald ash borer, Agrilus planipennis Fairmaire, has destroyed millions of ash trees (Fraxinus spp.) in North America since first identified in Detroit in 2002. With species of ash distributed throughout North America, it is easy to speculate the extinction of all susceptible species of ash on the continent given a lack of physical, environmental, or climactic barrier for dispersal of the insect. We investigated water balance characteristics of emerald ash borer ova by using gravimetric methods in an effort to measure their response to heat- and water-stress and explore possible influences this stress may have on the ecology and physiology of the ovum. We also explored the possible water balance benefit of a peculiar, “clustering,” oviposition behavior, as well as the difference in responses to stress between ova from a laboratory colony and ova from two wild populations. We found no evidence of water vapor absorption as a water balance strategy; rather enhanced water retention, resistance to desiccation, and viability with low water content were important survival strategies for these ova. Surface lipids resist thermal breakdown as indicated by ova having no detectable critical transition temperature, maintaining their water-proofing function as temperature rises. The observed “clustering” behavior had no desiccation-avoidance benefit and ova from the wild populations behaved almost identically to the ova from the lab colony, although the lab ova were slightly larger and more sensitive to dehydration. Given this new information, there appears to be no heat- or water-stress barriers for the dispersal of this devastating pest at the ovum stage.

Black soldier flies, Hermetia illucens (L.) (Diptera: Stratiomyidae), are of particular interest for their applications in waste management. Feeding on decaying organic waste, black soldier flies successfully reduce manure in confined animal feeding operations of poultry, swine, and cattle. To optimize waste conversion in confined animal feeding operations and landfill facilities, it is imperative to optimize black soldier fly development. Unfortunately, black soldier flies only convert waste during their larval feeding stages and therefore it is of interest to optimize the nonfeeding stages of development, specifically, the postfeeding and pupal stages. The time spent in these stages is thought to be determined by the pupation substrate encountered by the postfeeding larvae. The objective of this study was to determine the effect different pupation substrates have on postfeeding development time, pupation time, and adult emergence success. Five pupation substrates were compared: wood shavings, potting soil, topsoil, sand, and nothing. Postfeeding larvae took longer to reach pupation in the absence of a pupation substrate, although reaching pupation in the shortest time in potting soil and wood shavings. The time spent in the pupal stage was shortest in the absence of a pupation substrate. However, fewer adults emerged when a pupation substrate was not provided.

Hippodamia variegata (Goeze) is a widespread predator of aphid and has been reported as the most important naturally occurring enemy of aphids, in many countries. In this study, fluctuating levels of cryoprotectants in nonoverwintering and overwintering coccinellids were assessed in field and natural overwintering sites in Hamadan, Iran, from September of 2010 to June of 2011. Moreover, accumulations of polyols were investigated in response to subzero temperatures. Results demonstrated that concentrations of cryoprotectants changed during the study period under natural conditions. Large amounts of metabolic reserves, in the form of glycogen, accumulated before overwintering. Glycogen began to breakdown but polyols accumulated when ambient temperature decreased from October to December. Overwintering coccinellids displayed a threefold increase in levels of trehalose and a fivefold increase in levels of glucose and total cryoprotectants, but there was even a 45-fold increase in myo-inositol content when subzero temperatures were experienced. It was suggested that myo-inositol and glucose are the major cryoprotectants components in this species. In tests for cold response, the optimal temperature for polyol synthesis seems to be below -3°C. From November to February, all the collected coccinellids that had been kept at 10°C in the laboratory were dead after 30 d, indicating that high temperatures were not favorable for overwintering of this population. Moreover, exposure to high temperatures resulted in rapid catabolism of sugar alcohols. This result demonstrated significant correlation between ambient temperature decrease and accumulation of polyols, suggesting that low temperatures are responsible for polyols synthesis in this species.

The potato psyllid, Bactericera cockerelli (Sulc) (Hemiptera: Triozidae), is an economically important pest of potato (Solanum tuberosum L.) crops across the western and central United States, as it is known to cause psyllid yellows disease and to transmit the bacterium that causes zebra chip disease. Recent genotyping of B. cockerelli collected during the 2011 potato growing season identified three psyllid haplotypes within the western and central United States according to their geographical regions: northwestern, western, and central. To understand potato psyllid population dynamics before the year 2011, high resolution melting analysis of the B. cockerelli mitochondrial cytochrome oxidase I-like gene was used to identify the haplotypes of over 450 archived psyllids collected in the western and central United States between the years 1998 and 2010. Results show that the northwestern haplotype was present in Washington State as early as 1998 and has persisted in this region since that time. Likewise, psyllids of the western haplotype have also been present in Washington and Oregon before 2011.