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The stink bugs Acrosternum arabicum Wagner and Brachynema germari Kolenati (Hemiptera: Pentatomidae) damage developing pistachio nuts in Iran. Ooencyrtus egeria Huang and Noyes (Hymenoptera: Encyrtidae) parasitizes eggs of both species, alternating between them seasonally. We compared the biological and life history attributes of O. egeria reared for 3 generations on each host species with those that had been transferred to the alternate host for 2 generations. We also tested female responses to host egg density. Eggs of B. germari were parasitized at higher rates and yielded faster wasp development, heavier female progeny with greater fecundity, and a more female-biased sex ratio, than eggs of A. arabicum. Rearing on A. arabicum did not diminish wasp fitness on B. germari , and the F1 progeny of wasps switched to A. arabicum inherited some beneficial parental effects from rearing on B. germari. Regardless of host species, females parasitized fewer eggs in 8 h as density increased from 10 to 30 eggs, but progeny sex ratio (% female) increased. The anomalous response to host density appears to arise from a combination of behavioral and egg load constraints. Females mature only 10–12 eggs per day. Carefully inspect egg clusters before selecting the most suitable eggs for oviposition, a more time-consuming process for large clusters. Our results indicate that rearing O. egeria on eggs of A. arabicum , which are more convenient and cost-effective to produce than those of B. germari , will not diminish its performance on B. germari following augmentative release, beyond a slight reduction in female fecundity. [ABSTRACT FROM AUTHOR]

The two-spotted spider mite, Tetranychus urticae Koch (TSSM), is an important cosmopolitan pest of agricultural crops that is often managed in greenhouses by augmentation of predatory mites in combination with acaricides. Here we examined the transgenerational effects of low lethal concentrations of a widely-used acaricide, Oberon Speed® (a combination of spiromesifen and abamectin), on the life history traits and population growth of T. urticae and two of its predators, Phytoseiulus persimilis Athias-Henriot and Amblyseius swirskii Athias-Henriot (Acari: Phytoseiidae). The concentrations employed corresponded to the LC10, LC20 and LC30 values estimated for TSSM protonymphs 48 h post-exposure in a topical bioassay, which yielded an LC50 value of 207.2 ppm. Parental exposure of TSSM to all three low concentrations increased the total developmental time of progeny; both the LC20 and LC30 treatments reduced adult longevity and number of oviposition days, but only the LC30 treatment increased the preoviposition period. Similarly, both the LC20 and LC30 treatments significantly reduced life table parameters (r, R0, λ, and GRR), and increased generation time (T) and population doubling time (DT). Although maternal exposure to the acaricide had various impacts on progeny life history, A. swirskii was less affected than P. persimilis, suggesting the former species would be more compatible for integration with Oberon Speed® for control of T. urticae in greenhouse vegetable production. [ABSTRACT FROM AUTHOR]

Simple Summary: Laboratory and field observations were used to evaluate the compatibility of yellow sticky cards with augmentative releases of T. dendrolimi for control of orchard pests, particularly C. sasakii and G. molesta. Female T. dendrolimi showed stronger attraction to yellow and white than to red, green or blue. Yellow sticky cards trapped significant numbers of T. dendrolimi in the field, reducing biological control of C. sasakii as well as the number of lacewings naturally recruited to the orchard. Judicious use of yellow sticky cards in orchards is therefore recommended to avoid disruption of biological control, specifically removing them in May before peak flights of moth pests require releases of egg parasitoids. Integrated pest management relies upon mutual compatibility among pest control tactics. The fruit-boring moths Carposina sasakii and Grapholita molesta can be devastating pests of pome and stone fruit production. Trichogramma dendrolimi parasitizes the eggs of these pests, preventing their eclosion, but its efficacy can be reduced by other pest control tactics. We tested T. dendrolimi attraction to five colors, and moth attraction to six colors, in laboratory choice tests, and thereafter deployed yellow sticky cards in tandem with releases of T. dendrolimi in field trials in a pear orchard. Yellow sticky cards deployed at high density trapped T. dendrolimi and reduced their numbers post-release. They also trapped adult G. molesta, which appeared to compensate for reduced egg parasitism on this species, but not on C. sasakii, which had higher abundance in plots with yellow sticky cards. The cards also captured adult lacewings, likely reducing their numbers in the field, but did not capture large numbers of lady beetles. The results suggest that yellow sticky cards can be used at high density to control aphids, psyllids and leafhoppers in early spring (March and April) when natural enemies are in low numbers, then removed in May so as not to interfere with augmentative releases of T. dendrolimi that must be timed to coincide with peak flights of fruit-boring moths. This strategy should enhance the compatibility of yellow sticky cards with egg parasitoid releases. [ABSTRACT FROM AUTHOR]

Vector-borne viruses can modify the phenotype of their host plants to manipulate the behavior of their vectors and maximize their dissemination. The soybean aphid, Aphis glycines Matsumura (Hemiptera: Aphididae), is a primary vector of soybean mosaic virus (SMV), a non-persistent potyvirus that is a serious disease of soybean. We investigated mechanisms by which SMV changes A. glycines feeding and dispersal behavior via virus-induced modifications of plant phenotype. These changes affect gustatory, visual and olfactory cues that alter the behavior of both viruliferous and virus-free aphids to enhance virus acquisition and transmission. SMV-infected soybean seedlings exhibited up-regulation of the amino acids threonine and tyrosine which rendered viruliferous aphids more restless and prone to dispersal. Whereas dispersing viruliferous A. glycines preferred to settle and feed on virus-free soybean seedlings, virus-free aphids preferred SMV-infected seedlings. Volatile cues emanating from SMV-infected seedlings, primarily up-regulated methyl salicylate and down-regulated (Z)-3-hexen-1-ol, were implicated in repulsion of viruliferous aphids, whereas the mottled yellow coloration of SMV-infected seedlings was a visual attractant for aphids regardless of virus status. Our results reveal how a non-persistent virus uses multimodal 'push and pull' mechanisms to manipulate vector behavior for its own benefit, and suggests new avenues for exploring the mechanisms of altered behavior in viruliferous aphids. [ABSTRACT FROM AUTHOR]

Trissolcus spp. are egg parasitoids of sunn pest, Eurygasterintegriceps Puton (Hemiptera: Scutelleridae). Direct (extrinsic) competition between female T.grandis and T.vassilievi was investigated in the laboratory by releasing different numbers (from one to 16) of one or both species into a multi-patch environment consisting different numbers of E.integriceps egg masses. Larval (intrinsic) competition was examined in host eggs multiparasitized at intervals ranging from 0 to 48 h. Survival of females was also assayed when stored at 4 °C. Trissolcusgrandis reduced the searching efficiency of congeneric rivals more than did T.vassilievi, and was a superior intrinsic competitor within multiparasitized eggs, although both species benefited from a significant 'first attack' advantage. Trissolcusvassilievi was more efficient than T.grandis when parasitizing host eggs at high conspecific densities. Mortality at 4 °C was lower in groups ≥ 10 than in groups ≤ 5, and T.grandis survived longer than T.vassilievi. [ABSTRACT FROM AUTHOR]

The carob moth, Ectomyelois ceratoniae (Zeller) (Lepidoptera: Pyralidae), is an important pest of pistachio causing direct damage to nuts during ripening, and in storage. We examined the tritrophic effects of 5 pistachio cultivars, representing the full range of kernel suitability for E. ceratoniae , on 2 larval parasitoids, Habrobracon hebetor (Say) (Hymenoptera: Braconidae), a gregarious, synovigenic, idiobiont, ectoparasitoid, and Venturia canescens Gravenhorst (Hymenoptera: Ichneumonidae), a solitary, pro-ovigenic, koinobiont, endoparasitoid. The suitability of pistachio cultivars for development and reproduction of the 2 parasitoids was closely correlated, despite their divergent lifestyles and developmental patterns, and paralleled variation in kernel suitability for host larvae. Although kernels of the most resistant cultivar reduced demographic parameters of the parasitoids, the potential impact on numerical responses was minor. Successful biological control of carob moth within the vulnerable period of nut ripening will likely depend on the functional responses of earlier generations of adult parasitoids emerging from other fruit and nut crops, or those released in an augmentation program. [ABSTRACT FROM AUTHOR]

Simple Summary: This study used field observations to demonstrate that intercropping okra in a pear orchard reduced pheromone trap catches of Grapholita molesta in two years, whereas intercropping with castor bean reduced them in one year, relative to natural grass cover. GC-MS assays showed that hydrocarbons, phenols, and ketones predominated in the volatiles emitted from okra, whereas aldehydes, ketones, and esters were the most abundant volatiles emitted from castor bean. Five of these compounds exhibited repellency to G. molesta in olfactometry assays, especially cinnamaldehyde, dibutyl phthalate, and thymol; the former also served as an attractant for the egg parasitoid Trichogamma dendrolimi, which is often used in augmentation biocontrol of the moth. Intercrops can lower pest densities by increasing plant diversity, altering chemical communication in the arthropod community, and integrating well with other IPM tactics. We used two years of field observations and Y-tube olfactometer assays to explore the effects of intercropping a pear orchard with okra and castor bean on the cosmopolitan fruit-boring pest Grapholita molesta (Lepidoptera: Tortricidae). Intercropping okra reduced G. molesta trap catches in the pear orchard in both years, and intercropping with castor bean reduced them in the second year. Hydrocarbons, phenols, and ketones predominated in the GC-MS assay of okra volatiles, whereas castor bean volatiles were rich in aldehydes, ketones, and esters. Five of the commercially available volatiles released by these plants exhibited repellency to G. molesta in olfactometer trials, especially cinnamaldehyde, dibutyl phthalate, and thymol; the former compound also exhibited attraction to the egg parasitoid Trichogamma dendrolimi (Hymenoptera: Trichogrammatidae). In addition to their repellent properties, okra and castor bean may enhance integrated control of G. molesta in orchards by hosting prey that support populations of generalist predators that either provide biological pest control services within the orchard ecosystem or generate non-consumptive effects that contribute to pest deterence. Among the plant volatiles evaluated, cinnamaldehyde has the best potential for deployment in orchards to repel G. molesta without disrupting augmentative releases of T. dendrolimi. [ABSTRACT FROM AUTHOR]

DESIR is, together with S3-LEB, the low-energy part of the SPIRAL2 ISOL facility at GANIL. The High-Resolution mass Separator (HRS) included in DESIR is a 180° symmetric online separator with two 90° magnetic dipole sections arranged with electrostatic quadrupoles, sextupoles and a 48-pole electrostatic multipole on the mid plane. The HRS is now completely mounted at LP2i Bordeaux and under commissioning for the next years before its transfer to the entrance of the DESIR facility. Optical aberrations, mainly introduced by the dipoles, must be corrected up to the highest possible order to guarantee an optimal resolution of the separator. They are measured with a pepperpot-type emittance-meter, analyzed then corrected with the multipole. Up to now, 2nd order (hexapolar) and part of 3rd order (octupolar) aberrations are under control and an optimal FWHM separation has been achieved for two identical beams with a relative energy difference of Δ E / E (≡ Δ M / M) = 1 / 23400. In this paper, we present the effects of optical aberrations on the beam and its emittance figure, as well as the effect of the associated corrections with the multipole. Finally, we will show the latest resolution measurements and associated methodology. [ABSTRACT FROM AUTHOR]

The carob moth, Ectomyelois ceratoniae (Zeller) (Lepidoptera: Pyralidae) is a serious pest of fruit and nut crops worldwide that causes significant losses in Iranian pistachio orchards. In order to assess variation among cultivars is susceptibility to carob moth and biochemical correlates, the present study evaluated the suitability of kernels of 10 pistachio cultivars for E. ceratoniae development and reproductive performance under laboratory conditions: 25 ± 1°C, 65 ± 5% RH and a 16:8 (L:D) photoperiod. The primary and secondary metabolites of nuts were quantified and correlated with life history traits and various metrics of biological performance and indices of relative suitability were calculated. Nut protein content averaged 18.4 ± 0.1% and did not vary significantly among cultivars. Two cultivars yielded significantly slower larval development and lower values for relative growth rate, female longevity and fecundity, relative to all others. Suitability indices calculated from moth life history parameters varied by a factor of 4.66 across cultivars, with values <1 for the two most resistant varieties. The latter cultivars were less consumed by larvae and were lowest in carbohydrate content and efficiency of food conversion, but ranked highest in total phenolics, tannins and flavonoids. Linear regressions indicated that carbohydrate content was positively correlated with kernel suitability for larval development and adult reproduction, whereas total phenolics, tannins, flavonoids and anthocyanins were all negatively correlated. The implications of these findings for integrated management of E. ceratoniae in pistachio orchards, and the possibility of improving pistachio resistance to carob moth, are discussed. [ABSTRACT FROM AUTHOR]

Baculoviruses are highly evolved parasites that genetically reprogram the developing phenotype of their host insect to produce a vessel for virus replication and dispersal. Here we show that larvae of Helicoverpa armigera infected with HearNPV accumulate glucose in the midgut, which reduces food consumption and alters the dynamics of pathways governing metabolism and immunity. We used transcriptomics to demonstrate the role of the insulin signalling pathway in regulating the HearNPV infection process. Dietary restriction decreased mortality of infected larvae and reduced viral replication prior to death, whereas dietary supplementation with glucose produced the opposite effects. The expression of most tricarboxylic acid cycle (TCA) and energy metabolism‐related genes was reduced in infected larvae, whereas the expression of immunity‐, glycolysis‐ and insulin‐related genes was enhanced. Treatment of infected larvae with insulin increased their survival, reduced viral replication and inhibited climbing behaviour compared to a control treatment with DMSO, whereas RNAi suppression of the insulin receptor gene produced the opposite effects. Inhibition of glycolysis with dichloroacetate (DCA) promoted viral replication and accelerated larval death, but inhibition of the TCA cycle with 2‐deoxyglucose (2‐DG) did not, although both diminished climbing behaviour. This work demonstrates that successful baculovirus infections hinge on metabolic reprogramming of the host and concurrent suppression of immune responses in the larval midgut, with the insulin signalling pathway mediating a trade‐off between glucose metabolism and virus resistance. [ABSTRACT FROM AUTHOR]

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Characterizing a (high resolution) magnetic separator may not be easy as it is difficult to find a stable ion source providing species with close enough masses to separate. As these instruments perform a momentum separation (B ρ = p / q), their mass and energy resolution are strictly the same. One can use this property to characterize the mass resolution of a spectrometer through its energy resolution. Hence, multiple identical beams with close energies can be used to test a magnetic spectrometer in almost real conditions. The method we present allows to populate an ion beam with multiple close and well-defined energies. It consists in using an arbitrary pulse generator to temporally change the acceleration potential of the ion source, and create a custom energy distribution, where the length in time of the pulse is the production ratio of the contaminant and the amplitude its relative energy (i.e. its mass). [Display omitted] [ABSTRACT FROM AUTHOR]

As an intermediate molecule in the Insulin/Insulin‐like growth factor signalling pathway (IIS), the insulin receptor (IR) plays vital roles linking nutritional signals to the downstream regulation of metabolic homeostasis, development, metamorphosis, reproduction and stress responses. In the present study, we describe the molecular characteristics of IR in the cosmopolitan fruit boring pest, Grapholita molesta, and its predicted posttranscription regulator miR‐982490, and elucidate its regulatory roles in glucolipid homeostasis and metamorphosis. Phylogenetic and domain analyses indicate that lepidopteran IRs normally cluster within families, and that four main domains are conserved in GmIR and those of other Lepidoptera. Bio‐informatic prediction, synchronic expression profile evaluation and dual luciferase reporter assays indicated negative regulation of GmIR by miR‐982490. Injection of miR‐982490 agomir into fifth instar larvae yielded effects similar to dsGmIR injection, resulting in enhanced levels of trehalose and triglyceride in haemolymph, and reduced pupation success and pupal weight, both of which could be rescued by co‐injection of dsGmIR and miR‐982490 antagomir. We infer that GmIR regulates glucolipid homeostasis and affects G. molesta metamorphosis via interactions with its posttranscriptional regulator miR‐982490. This study expands our understanding of the regulatory network of IIS in insect nutritional homeostasis and development. [ABSTRACT FROM AUTHOR]

We examined differences in the physiology and life history between dimorphs of the common pistachio psyllid, Agonoscena pistaciae (Burckhardt and Lauterer) (Hemiptera: Aphalaridae), and how they differ in elicitating host plant production of key metabolites and volatile compounds involved in the recruitment of herbivores and natural enemies. Summer morphs had higher activities of glutathione S-transferase, carboxylesterase, acetylcholinesterase, and cytochrome P450 monooxygenase, superoxide dismutase, catalase, peroxidase, phenoloxidase, and a higher total protein content compared to winter morphs, whereas the latter had higher amounts of lipid, carbohydrate, and glycogen. Winter morphs were heavier, with a higher chitin content and longer preoviposition period, but greater fecundity and longevity than summer morphs. A lower LC50 to thiamethoxam for winter morphs resulted in higher mortality following exposure to the recommended rate of this insecticide in a greenhouse trial. Feeding by winter morphs elicited more strongly the release of volatile compounds known to be attractive to other herbivores, whereas feeding by summer morphs elicited more strongly the release of volatiles implicated in the attraction of natural enemies. Feeding by psyllids increased the concentrations of nitrogenous compounds, carbohydrates, vitamins, and amino acids in plants, the winter morph eliciting larger changes and more improved host plant quality. We conclude that winter morphs are more vulnerable targets for chemical control in early spring, whereas management of summer morphs could rely more on conservation biological control. [ABSTRACT FROM AUTHOR]

Industrial‐scale agriculture creates a mosaic of large monocultures in the landscape, where seasonal cropping cycles generate discontinuous resource availability for insect predators both spatially and temporally. In this environment, selection will favor predator movement and reproductive behaviors that optimize the location and effective utilization of resource (prey) pulses that are both patchy and ephemeral in nature. Using a model system to study predator movement and reproduction, we tested how discontinuous periods of food resource access that mimic fluctuating resource populations (aphids) would influence flight behavior and reproduction of a highly mobile predator, Hippodamia convergens (convergent lady beetle), and possibly modify energetic trade‐offs between these behaviors. Adult beetles were provided either short (3 h) or long (6 h) food pulses daily (continuous availability) or short (6 h) or long (12 h) food pulses every other day (discontinuous availability). We measured preoviposition period, fecundity, and fertility during an 18‐day oviposition period, and female tethered flight activity (3 h) before and after the oviposition period. We found that discontinuous food access delayed the onset of oviposition in the high food quantity treatment; fewer females laid eggs overall, and 18‐day fecundity was lower compared with continuous provision of the same food quantity. A longer preoviposition period was associated with fewer reproductive days and lower fitness. Flight distance and fecundity were negatively correlated, suggesting that energetic expenditure in flight can deplete energetic reserves otherwise used for subsequent reproduction. The negative effects of discontinuous resource access at fine temporal scales reveal how gaps in resource availability could influence lady beetle population dynamics and their ecosystem services within the agricultural landscape. [ABSTRACT FROM AUTHOR]

The Tomato Leaf Miner (TLM), Tuta absoluta (Meyrick) (Lepidoptera: Gelechiidae), is a cosmopolitan tomato pest that has driven a renewed reliance on pesticides in tomato production, negatively affecting biological control of other pests and creating environmental and health hazards. We tested five locally important Iranian tomato cultivars (TD, Karon, Petoprid, Matin, and 8320) for constituitive resistance to TLM by comparing its biological performance and life table parameters under standardized laboratory conditions (27.5±1°C, 65±5% RH, 16 L:8 D hours photoperiod). Survival and developmental rates of immature stages varied significantly among cultivars, as did female fecundity and main parameters of the life table. Karon was most suceptible, affording 90% juvenile TLM survival, the fastest development, and the highest female fecundity, with cultivar 8320 not significantly different in these regards. By contrast, Matin ranked most resistant; i.e. only 59% of larvae survived, and female fecundity was almost halved. TD was the next most resistant, being not significantly different from Matin in these metrics. The intrinsic rates of increase (r), in descending order, were Karon (0.178), 8320 (0.169), TD (0.146), Petoprid (0.138), and Matin (0.111). Matin and TD had the highest densities of glandular trichomes on adaxial leaf surfaces. These findings indicate that the Matin, Petoprid and TD are more resistant than the other cultivars and have potential as one component of an IPM strategy to manage T. absoluta. [ABSTRACT FROM AUTHOR]

Baculoviruses can induce climbing behaviour in their caterpillar hosts to ensure they die at elevated positions to enhance virus transmission, providing an excellent model to study parasitic manipulation of host behaviour. Here, we demonstrate that climbing behaviour occurred mostly during daylight hours, and that the height at death of Helicoverpa armigera single nucleopolyhedrovirus (HearNPV)‐infected larvae increases with the height of the light source. Phototaxic and electroretinogram (ERG) responses were enhanced after HearNPV‐infection in host larvae, and ablation of stemmata in infected larvae prevented both phototaxis and climbing behaviour. Through transcriptome and quantitative PCR, we confirmed that two opsin genes (a blue light‐sensitive gene, HaBL; and a long wave‐sensitive gene, HaLW) as well as the TRPL (transient receptor potential‐like channel protein) gene, all integral to the host's visual perception pathway, were significantly upregulated after HearNPV infection. Knockout of HaBL, HaLW, or TRPL genes using the CRISPR/Cas9 system resulted in significantly reduced ERG responses, phototaxis, and climbing behaviour in HearNPV‐infected larvae. These results reveal that HearNPV alters the expression of specific genes to hijack host visual perception at fundamental levels—photoreception and phototransduction—in order to induce climbing behaviour in host larvae. [ABSTRACT FROM AUTHOR]

The giant sugarcane borer, Telchin licus (Drury) (Lepidoptera: Castniidae), also known as the banana stem borer, is an economically important pest of sugarcane in eastern Colombia. The presence of larval and pupal stages within stalks makes biological control of this pest difficult, and growers often resort to insecticide applications. Hilling up the soil around the base of plants, or soil mounding, is a cultural practice sometimes used to improve rooting in sugarcane. Because mature larvae cut holes in stalks close to ground level through which they can emerge as an adult, we hypothesized that soil mounding would impede adult emergence, and thus contribute to population reduction. Two experiments were conducted in fields with significant infestations of this pest in Puerto López, Meta, Colombia, during the seasons of adult emergence in this region (Apr–May and Oct–Nov). Manual mounding of soil to a height of 20 cm was tested in the first trial, and mechanized mounding of soil in the second, which also compared 2 mounding heights (10 and 20 cm). In both cases, 2 m row transects of plants were caged to collect emergent adults. Adult emergence was reduced up to 65% in all mounding treatments, whether manual or mechanical, and regardless of mounding height, demonstrating that this cultural practice could be a useful tactic for inclusion in an integrated management program for this pest. However, as with any other cultural practice in pest management, region-wide implementation likely would be required to impact local population densities, and efficacy will depend further on low levels of moth immigration from alternative host plants. [ABSTRACT FROM AUTHOR]

Aphids parasitized in later instars can give birth to several nymphs before their reproduction is curtailed by the developing parasitoid. We examined the life histories of Aphis fabae Scopoli born to mothers parasitized by Lysiphlebus fabarum Marshall, and their suitability as subsequent hosts, to test the 'fecundity compensation' hypothesis. Maternal parasitism negatively impacted life history parameters, resulting in reduced estimates of population increase (rm, R0, and λ), and increased generation time (GT) and doubling time (DT). These impacts were greater when the larva developing in the mother turned out to be female rather than male, and greater still when mothers were superparasitized. Maternal parasitism produced aphids with shorter hind tibia (HTL), at birth and at maturity, but their developmental time was unaffected. Although female L. fabarum readily accepted such aphids for oviposition, rates of mummification and wasp emergence were lower, and more so when the maternal parasitoid was female. The resulting parasitoids took longer to develop than progeny from control wasps, had shorter HTLs, lower egg loads, smaller eggs, and produced fewer mummies with lower rates of adult emergence, all differences that were more pronounced when the maternal parasitoid was female. The progeny of these wasps exhibited similar impairments to these biological parameters as their parents, demonstrating that the negative impacts of development in maternally parasitized hosts extended for at least two generations. Thus, our results do not support fecundity compensation, but suggest that any benefits of post-parasitism reproduction will be offset by reduced fitness in both aphid progeny and the parasitoids that develop in them. [ABSTRACT FROM AUTHOR]

We studied the effect of Trichogramma brassicae Bezdenko (Hymenoptera: Trichogrammatidae) parasitism of Tuta absoluta Meyrick (Lepidoptera: Gelechiidae) eggs on the foraging behavior of Nabis pseudoferus Remane (Hemiptera: Nabidae) feeding on T. absoluta eggs of different ages. Older parasitized eggs (48–72 h old) were rejected after probing with the probosis. A separate experiment showed that probing did not harm developing parasitoids. Bugs greatly reduced their feeding times on older parasitized eggs and spent more time grooming and probing eggs and leaves. Predators exhibited a type III functional response to 24 h-old eggs, but a type II response to older eggs, whether parasitized or not. 24 h-old eggs suffered higher attack rates, and required less handling time than older eggs. Although the predatory efficiency of N. pseudoferus was reduced in the presence of parasitized eggs, the partial refuge enjoyed by T. brassicae in older eggs may permit an additive impact on the pest, and should facilitate the joint augmentation of both species against T. absoluta. [ABSTRACT FROM AUTHOR]

BACKGROUND: Oriental fruit moth, Grapholita molesta (Busck) (Lepidoptera: Tortricidae) is a cosmopolitan pests of fruit trees in temperate regions. Control of G. molesta is challenging because larvae feed in concealed locations and have evolved resistance to many pesticides. We compared three commercially available species of Trichogramma for efficacy against G. molesta in the laboratory assays and tested releases of the promising species in a pear orchard. RESULTS: Laboratory assays indicated that Trichogramma dendrolimi parasitized G. molesta at the highest rate. Parasitoids took longer to oviposit in older host eggs, and fewer eggs were parasitized when they were more than 3 days old. Field tests produced ca 60% cumulative parasitism of sentinel G. molesta eggs with one release of Trichogramma dendrolimi, with most parasitism occurring within 24 h. Female wasps dispersed up to 12 m from release points with a bias toward upwind movement. CONCLUSION: We calculated that, for each generation of G. molesta, 900 000 wasps per hectare, in three releases 3 days apart, each distributed among release points 10 m apart, would reduce fruit damage by half in an orchard where 50% of fruit would otherwise be damaged. Although augmentation of Trichogramma dendrolimi is a viable tactic for reducing G. molesta populations and fruit damage, it will require integration with other compatible control tactics in order to provide commercially acceptable levels of control in orchards experiencing significant pest pressure. © 2021 Society of Chemical Industry [ABSTRACT FROM AUTHOR]

The cyclopropene radical cation (c-C3H+4) is an important but poorly characterized three-memberedring hydrocarbon. We report on a measurement of the high-resolution photoelectron and photoionization spectra of cyclopropene and several deuterated isotopomers, from which we have determined the rovibrational energy level structure of the X+ ²B2 ground electronic state of c-C3H+4 at low energies for the first time. The synthesis of the partially deuterated isotopomers always resulted in mixtures of several isotopomers, differing in their number of D atoms and in the location of these atoms, so that the photoelectron spectra of deuterated samples are superpositions of the spectra of several isotopomers. The rotationally resolved spectra indicate a C2v-symmetric R0 structure for the ground electronic state of c-C3H+4. Two vibrational modes of c-C3H+4 are found to have vibrational wave numbers below 300 cm-1, which is surprising for such a small cyclic hydrocarbon. The analysis of the isotopic shifts of the vibrational levels enabled the assignment of the lowest-frequency mode (fundamental wave number of ≈110 cm-1 in c-C3H+4 ) to the CH2 torsional mode (v+8, A2 symmetry) and of the second-lowest-frequency mode (≈210 cm-1 in c-C3H+4) to a mode combining a CH out-of-plane with a CH2 rocking motion (v+15, B2 symmetry). The potential energy along the CH2 torsional coordinate is flat near the equilibrium structure and leads to a pronounced anharmonicity. [ABSTRACT FROM AUTHOR]

Cantilevers with resonance frequency ranging from 1 MHz to 100MHz have been developed for dynamic atomic force microscopy. These sensors are fabricated from 3C-SiC epilayers grown on Si(100) substrates by low pressure chemical vapor deposition. They use an on-chip method both for driving and sensing the displacement of the cantilever. A first gold metallic loop deposited on top of the cantilever is used to drive its oscillation by electrothermal actuation. The sensing of this oscillation is performed by monitoring the resistance of a second Au loop. This metallic piezoresistive detection method has distinct advantages relative to more common semiconductor-based schemes. The optimization, design, fabrication, and characteristics of these cantilevers are discussed. [ABSTRACT FROM AUTHOR]

We estimated thermal developmental thresholds (T0) and degree‐day (DD) constants for the immature stages of two tephritid pests, Bactrocera zonata (Saunders) and Ceratitis capitata (Weidenmann). Males of both species were trapped in an Egyptian guava orchard during the fruiting seasons of 2016 and 2017 and trap catches were compared with peak flights predicted by the DD model based on local weather data. Ceratitis capitata had faster development than B. zonata at 20 and 25 °C, but their overall developmental rate was similar at 30 and 35 °C. The thermal threshold of development (T0) of B. zonata was higher than that of C. capitata, indicating greater sensitivity to cold. Although 35 °C yielded the fastest development of both species, survival was higher at 30 °C, with B. zonata experiencing a slight advantage, suggesting better tropical adaptation. Immature development of B. zonata and C. capitata was estimated to require 338 and 373 d, respectively, and 616 and 424 DD for a complete generation. Trap catches over both seasons showed good correspondence to peaks of fly activity predicted by the DD models; deviations from expectation ranged from 0 to 7 d for both fly species. Both species had four overlapping generations per season, with B. zonata abundance peaking in the first generation in both years, but only in 2016 for C. capitata. The models predict about eight and 12 generations per year in northeast Egypt for B. zonata and C. capitata, respectively. These models should be useful for timing pest control measures to coincide with periods of peak fly activity in fruit orchards. [ABSTRACT FROM AUTHOR]

The convergent lady beetle, Hippodamia convergens Guerin-Meneville, is a specialized predator of cereal aphids on the High Plains, completing its first generation each year in winter wheat, the resulting adults dispersing into summer crops and producing additional generations, contingent on the availability of aphids. In the present study, we tested the collective value of supplementary plant resources (sugars, pollen, and seedling wheat leaves), and small amounts of alternative prey, eggs of Ephestia kuehniella (Zeller) (Lepidoptera: Pyralidae), all provided together, for improving beetle life history and reproductive success even when suitable prey, Schizaphis graminum (Rondani) (Hemiptera: Aphididae), were provided ad libitum. Although a monotypic diet of S. graminum yielded slightly faster larval development and heavier adults than the omnivorous diet, preoviposition periods were extended and 21-d fecundities greatly reduced when this diet was continued through adult life, largely due to fewer oviposition days, although egg fertility was unaffected. The results highlight the critical importance of plant-derived resources even when suitable prey are not limiting. However, monotypic diet beetles that diapaused for 21 d in the presence of supplementary plant resources, plus moth eggs, achieved the same reproductive success as those reared on the omnivorous diet, with or without diapause, demonstrating that access to these resources post-emergence was sufficient to compensate for their absence during development. The diapause treatment itself had no impact on the fitness of beetles reared on the omnivorous diet, likely because neither its duration, nor the caloric restriction imposed, were sufficient to diminish reproductive effort. [ABSTRACT FROM AUTHOR]

Although the brown stink bug, Euschistus heros (F.) is susceptible to entomopathogenic fungi, only a single formulation is currently available on the Brazilian market for its control. The objective of this work was to isolate entomopathogenic fungi with potential to control E. heros, evaluate their virulence, and determine effective conidial concentrations. Thirty six different fungal isolates were obtained from soil samples and diseased insects and pure cultures of each were established on potato-dextrose agar. Suspensions of 1 × 108 conidia mL−1 were prepared from each isolate and a 5 μL aliquot was inoculated on the dorsum of adult stink bugs (n = 8 replications of 5 bugs each). Three isolates caused 100% mortality of bugs over a 15-day observation period. These were identified by molecular techniques as belonging to the Beauveria bassiana species complex and designated UFSM-1, UFSM-2 and UFSM-26. Further bioassays determined the LC50, LC90 and cumulative mortality functions caused by these three isolates. Isolates UFSM-1 and UFSM-2 stood out as highly virulence, with an LC90 of 5 × 109 conidia mL−1 in 9 days, compared to an LC90 of 8 × 1010 conidia mL−1 for strain UFSM-26. Application of 1 × 108 conidia mL−1 of UFSM-1 and UFSM-2 isolates killed 70% of stink bugs in nine days, whereas the same concentration of UFSM-26 killed only 12%. We conclude that isolates UFSM-1 and UFSM-2 warrant field tests as novel agents for biological control of E. heros. [ABSTRACT FROM AUTHOR]

Oenopia conglobata (Linnaeus) and Menochilus sexmaculatus Fabricius (Coleoptera: Coccinellidae) are important predators of the pistachio psyllid, Agonoscena pistaciae Burckhardt and Lauterer (Hemiptera: Psyllidae), a key pest of pistachio. The abundance of M. sexmaculatus has recently increased in pistachio orchards, while that of O. conglobata has declined. We designed laboratory experiments to (1) evaluate the potential for intraguild predation (IGP) between these two species, (2) detect any possible asymmetries in IGP interactions, and (3) characterize the sensitivity of IGP to varying densities of two extraguild (EG) prey, A. pistaciae and Aphis gossypii Glover (Hemiptera: Aphididae). We measured rates of IGP by fourth instar larvae and female adults (both starved for 12 h) on vulnerable immature life stages of the other species (eggs, first, and second instar larvae). IG and EG prey consumption were tallied after 12 h. All factors influenced rates of IGP, but species of IG predator, and life stage and density of EG prey, contributed the most variance. IGP decreased parabolically with increasing prey densities. IGP on eggs was higher than on first instars, which was higher than on second instars, suggesting palatability declined in later life stages. The larger M. sexmaculatus exhibited higher voracity than the smaller O. conglobata in both predation and IGP. Both species consumed more A. pistaciae than A. gossypii in all treatments, which may reflect either lower handling time or lower food value per prey. [ABSTRACT FROM AUTHOR]

The nutritional status of host plants can have direct impacts on herbivore physiology and insect–plant interactions. We investigated the effect of micronutrients, including manganese, iron, zinc, and copper, on cucumber plant physiology, and on the biology and physiology of a strain of Aphis gossypii Glover selected over 12 generations to be resistant to pirimicarb. The micronutrient treatment increased the activity of superoxide dismutase, ascorbate peroxidase, guaiacol peroxidase, polyphenol oxidase, and phenylalanine ammonia-lyase in cucumber plants, and also increased levels of total phenolics, hydrogen peroxide, salicylic acid, and total chlorophyl, whereas malondialdehyde levels were unaffected. Pirimicarb-resistant cotton aphids that fed on micronutritient-amended cucumber plants expressed significantly decreased levels of acetylcholinesterase and detoxifying enzymes, specifically glutathione S-transferase, and carboxylesterase. Analysis of energy reserves in resistant A. gossypii fed on micronutritient-amended plants revealed decreases in the lipid and protein contents of aphids, whereas glycogen and carbohydrate contents showed no response. Resistant cotton aphids fed on micronutritient-amended plants showed significantly reduced fecundity, longevity, and reproductive periods, and a 1.7-fold reduction in pirimicarb LC50 compared with those fed on control plants. We conclude that micronutrient amendment negatively impacts the biological performance of insecticide-resistant cotton aphids, and diminishes their resistance to pirimicarb. Both direct effects on plant health, such as enhanced inducible defenses, and indirect effects on aphid fitness, such as reduced biological performance and detoxification abilities, were implicated. Therefore, optimization of micronutrient amendments could be a useful complement to other tactics for managing insecticide-resistant A. gossypii on cucumbers, and warrants exploration in other contexts. [ABSTRACT FROM AUTHOR]

A standardized laboratory procedure tested the limb regeneration abilities of 18 populations (16 species) of lady beetles which were then scored, relative to unoperated controls, based on survival, the proportion regenerating the limb completely or partially, and the magnitude of developmental costs (delayed development, reduced body size) associated with limb ablation. Newly molted fourth instar larvae each had a single foreleg amputated at the base of the femur. All species except Propylea dissecta (Mulsant) showed some complete limb regeneration, with limb regeneration index (LRI) scores ranging from 0.025 to 0.905 out of a possible 1.00 (mean = 0.598). Eriopis connexa Germar, an aphidophagous neotropical species, scored the highest. Widely distributed species that dominate agricultural habitats all scored above 0.75, and the only herbivore, Henosepilachna argus (Geoffroy), scored second from lowest. Prolonged pupal development was the most common cost, occurring in nine species, and correlating negatively with regeneration. Taxonomic distance between species correlated with regeneration, but explained <5% of variation; principal component analysis indicated that the LRI was the main factor distinguishing species. We infer that this capacity is conserved, not because of any adaptive advantage conferred, but because the genes responsible are normally activated during pupal development to generate the adult body plan and reconstitute appendages with direct correspondence to larval progenitors. However, good regeneration capacity was associated with the ecological success of the species. In general, broad geographic distribution, guild dominance, polyphagy, interspecific competitiveness, phenotypic flexibility, and invasiveness were characteristics generally shared by species with high levels of regeneration. [ABSTRACT FROM AUTHOR]

Salicylic acid (SA) is a signaling molecule that can induce plant resistance to certain herbivores. Although the role of jasmonic acid in mediating mite-tomato plant interactions has been well studied, the role of salicylic acid has not. This study examined how the application of exogenous SA, via its effects on tomato plant physiology, alters the activity of mite digestive enzymes, mite energy reserves, and mite susceptibility to spirodiclofen. Enzymatic activity—including superoxide dismutase, ascorbate peroxidase, guaiacol peroxidase, polyphenol oxidase, and phenylalanine ammonia-lyase—along with contents of total phenolic, hydrogen peroxide, and total chlorophyll significantly increased in plants 24 h after treatment with 2 mM of SA. In contrast, catalase activity significantly decreased in treated plants, and malondialdehyde content was unaffected. Mites fed on tomato plants treated with SA had significantly lower glutathione S-transferase, esterase, α-amylase, and aminopeptidase activities than those fed on control plants. Energy reserve analyses demonstrated a significant decrease in contents of lipid, protein, and glycogen in mites fed on SA-treated plants, whereas carbohydrate content significantly increased. The LC50 of spirodiclofen was decreased 1.8-fold for Tetranychus urticae fed on SA-treated tomato plants compared to controls. Treatment of adult mites with 2 mM SA on leaf discs did not cause any direct mortality after 24 h. Finally, a greenhouse bioassay confirmed that spider mite mortality following exposure to spirodiclofen was significantly higher on SA plants than on control plants. Mortality of mites exposed to half of the recommended rate of spirodiclofen was similar to those exposed to the recommended rate when they were held on treated plants. These results have valuable implications for T. urticae management programs in tomato production. [ABSTRACT FROM AUTHOR]

Bacillus thuringiensis Berliner subsp. kurstaki (Btk) and Habrobracon hebetor Say are both biological control agents of Helicoverpa armigera Hubner. The present study evaluated their compatibility for combined application against this pest by examining the acceptability of Btk -inoculated hosts for H. hebetor females and testing for negative life-history impacts on developing progeny. Second-instar H. armigera larvae fed for 72 h on potted chickpea plants treated with three concentrations of Btk (LC15, LC35, and LC70) and were then used in bioassays of parasitoid development and parasitism behavior. Survival of parasitoids was significantly reduced, and immature development prolonged, on hosts fed chickpea plants treated with LC35 and LC70   Btk , but not on plants treated with LC15   Btk. Parasitoids failed to discriminate against hosts treated with LC15 or LC35   Btk in choice tests, but attacked fewer hosts treated with LC70   Btk , paralyzing and parasitizing more healthy hosts, and laying more eggs on them. In contrast, a no-choice test revealed that more hosts treated with LC35 and LC70   Btk were paralyzed compared with control or LC15-treated hosts, but the numbers of hosts parasitized and eggs laid did not vary among Btk treatments. Thus, females required an experience with healthy hosts, as they had in the choice test, to discriminate against diseased ones. We conclude that H. hebetor and Btk are compatible for joint application against H. armigera , which could potentially improve biological control of this pest. [ABSTRACT FROM AUTHOR]

Defoliation by the vegetable leafminer, Liriomyza sativae Blanchard (Diptera: Agromyzidae), was simulated by removing known amounts of leaf area with a hole punch in a glasshouse experiment that evaluated 21 combinations of defoliation intensity, timing and duration on cucumber yields. Defoliation was quantified in cm2‐days (leaf area removed x no. days), and linear regression was used to correlate yield losses to simulated damage. The probability of erroneous decisions associated with different intensities of sequential sampling was explored. Spatial heterogeneity in leafminer infestation and the cumulative impact of defoliation over time were both considered, and the economic costs associated with wrong decisions were also assessed. Significant yield loss was observed beyond 10,000 cm2‐days of defoliation, whereas lower defoliation levels were tolerated by plants. The economic injury level (EIL) rose at an increasing rate as the onset of defoliation moved later in the season. An algorithm was used to estimate monthly EILs that farmers can use to guide leafminer management decisions in cucumber and minimize their economic risk. [ABSTRACT FROM AUTHOR]

We examined the ability of Coleomegilla maculata DeGeer and Hippodamia convergens Guerin-Meneville to regenerate, during pupation, a foreleg amputated in the fourth instar. Leg regeneration was complete for 80.7% of amputated H. convergens larvae, with 12.5% regenerating partially, and 6.8% showing no regeneration. Regeneration in C. maculata was 72.2% complete, 20.5% partial, and 7.2% none, but mortality following ablation was slightly higher than for H. convergens (7.4 vs. 0.6%). Ablation/regeneration caused a slight delay in pupation, but pupation time, fresh mass at emergence, and reproductive performance remained unaffected in either species. Reciprocal crosses were made between regenerated and unoperated beetles, and 12 progeny reared from the second clutch of each female in all treatments. Mating treatment affected eclosion time in H. convergens , whereas in C. maculata , larval development and pupation time were also affected. Considering all treatments, larval mortality was higher in H. convergens than in C. maculata , but lower when both H. convergens parents regenerated. Parental mating treatment did not affect adult weight in either species, but development of C. maculata progeny was faster when only the sire regenerated, and slower when the only the dame regenerated, whereas progeny of regenerated sires completed pupated faster than those sired by controls. We infer that genes activated during regeneration have pleiotropic effects with subtle, gender-specific, epigenetic consequences. If these pleiotropic effects are genetically linked to important traits, regenerative genetic elements could be conserved in coccinellids via natural selection acting on these traits, rather than on regenerative ability per se. [ABSTRACT FROM AUTHOR]

Cotton bollworm, Helicoverpa armigera Hubner, is a cosmopolitan polyphagous pest of many crops. Habrobracon hebetor Say and Helicoverpa armigera nucleopolyhedrovirus (HearNPV) are two important biocontrol agents used to manage this pest, sometimes in combination. We evaluated the sublethal effects of HearNPV on H. hebetor life table parameters under laboratory conditions when its host (second instar H. armigera) was treated with HearNPV, and tested H. hebetor females for their ability to discriminate against inoculated hosts. Emergence of adults reared as solitary larvae was reduced by half on LC30-inoculated larvae compared to controls, but not on LC5 or LC15-inoculated hosts. Low concentrations (LC5, LC15, and LC30) of HearNPV had no effects on overall parasitoid developmental time, but longevity and lifetime fecundity was reduced for females emerging from hosts receiving the LC30 treatment. Net reproductive rate (R 0), intrinsic rate of increase (r m ), and finite rate of increase (λ) were all decreased in a concentration-dependent manner in the LC15 and LC30 treatments, as were female life expectancy, age-specific survivorship (lx), and age-specific fecundity (mx), whereas population doubling time (DT) increased. Parasitoids did not discriminate against LC15-inoculated larvae in choice or no-choice tests, but parasitized more LC50-inoculated hosts than controls in the choice test, with no significant differences in total numbers of eggs laid in either case. Although parasitoids suffered some loss of fitness in HearNPV-inoculated hosts under these laboratory conditions, these agents still appear compatible for joint application against H. armigera under field conditions, provided parasitoid releases are made 2 d after NPV application. [ABSTRACT FROM AUTHOR]

Grapholita molesta , the oriental fruit moth, is a serious global pest of many Rosaceae fruit trees. Gut microorganisms play important roles in host nutrition, digestion, detoxification, and resistance to pathogens. However, there are few studies on the microbiota of G. molesta , particularly during metamorphosis. Here, the diversity of gut microbiota across the holometabolous life cycle of G. molesta was investigated comprehensively by Illumina high-throughput sequencing technology. The results showed that the microbiota associated with eggs had a high number of operational taxonomic units (OTUs). OTU and species richness in early-instar larvae (first and second instars) were significantly higher than those in late-instar larvae (third to fifth instars). Species richness increased again in male pupae and adults, apparently during the process of metamorphosis, compared to late-instar larvae. Proteobacteria and Firmicutes were the dominant phyla in the gut and underwent notable changes during metamorphosis. At the genus level, gut microbial community shifts from Gluconobacter and Pantoea in early-instar larvae to Enterococcus and Enterobacter in late-instar larvae and to Serratia in pupae were apparent, in concert with host developmental changes. Principal coordinate analysis (PCoA) and linear discriminant analysis effect size (LEfSe) analyses confirmed the differences in the structure of gut microbiota across different developmental stages. In addition, sex-dependent bacterial community differences were observed. Microbial interaction network analysis showed different correlations among intestinal microbes at each developmental stage of G. molesta , which may result from the different abundance and diversity of gut microbiota at different life stages. Phylogenetic Investigation of Communities by Reconstruction of Unobserved States (PICRUSt) analysis indicated that most functional prediction categories of gut microbiota were related to membrane transport, carbohydrate and amino acid metabolism, and DNA replication and repair. Bacteria isolated by conventional culture-dependent methods belonged to Proteobacteria, Firmicutes, and Actinobacteria, which was consistent with high-throughput sequencing results. In conclusion, exploration of gut bacterial community composition in the gut of G. molesta should shed light into deeper understanding about the intricate associations between microbiota and host and might provide clues to the development of novel pest management strategies against fruit borers. [ABSTRACT FROM AUTHOR]

The egg parasitoid Trissolcus vassilievi (Mayr) is a key natural enemy of sunn pest, Eurygaster integriceps Puton (Hemiptera: Scutelleridae). This laboratory study examined how the aggregation of parasitoids varied in response to host density and numbers of foraging conspecifics. Five host densities (1, 2, 4, 8, and 15 clutches of E. integriceps eggs), were offered simultaneously to 1, 2, 4, 8, or 16 female wasps in a standardized arena (30 cm diameter) and patch residence times were recorded. Patch residence time was strongly correlated with parasitism, and increased as the number of host clutches increased up to eight, but declined when more clutches were offered. Wasps displayed low mobility and tended to remain in the patch initially encountered, even when it contained few egg masses. At higher wasp densities, patches were occupied more quickly, host exploitation began sooner, and per capita handling time was reduced. However, total patch residence times were similar across all densities. Thus, females responded to conspecifics with increased movement, which increased dispersal and resulted in a more homogeneous distribution of wasps among patches. Pseudo-interference, resulting from wasps remaining in some patches and neglecting others, had greater impact on final levels of host exploitation than did actual interference (patch abandonment following conspecific encounters). These phenomena resulted in decreased parasitoid searching rates and a 2-fold increase in host survival at higher wasp densities. [ABSTRACT FROM AUTHOR]

Invasive airborne insects pose major challenges in natural resource and agriculture management, as they can rapidly spread over large distances and cross physical boundaries. Field monitoring and local management are important tools to prevent and control infestations but require additional coordination to be operative region-wide. Computational modeling techniques have been effective in simulating local population dynamics and in capturing spread of invasive species on a regional scale. We use an integrated ecological model to simulate local and regional infestation dynamics of sugarcane aphids, Melanaphis sacchari (Zehntner) (Hemiptera: Aphididae), on sorghum, Sorghum bicolor (L.) Moench (family Poaceae), in the southern to central Great Plains of the United States. Local dynamics of aphid populations on sorghum are simulated by a spatially explicit, individual-based model, whereas regional aphid migration is simulated by an atmospheric model that computes inert air particle (aphid) transport, dispersion, and deposition. Simulation results indicate timing of initial infestations in the south affects spatiotemporal patterns of infestation throughout the region. Probability of local infestations is a function of both percentage of land occupied by growing sorghum and prevailing winds. Thus, due to availability of sorghum, relatively later dates of initial infestation in the south will probably lead to infestations farther north that become established more quickly following the first appearance of aphids in the south. The model we present, in coordination with field monitoring schemes, could be applied as a forecasting tool in region-wide pest management systems. [ABSTRACT FROM AUTHOR]

Cotesia flavipes Cameron (Hymenoptera: Braconidae) is often augmented against Diatraea spp. (Lepidoptera: Crambidae) stem borers in the Americas. Diatraea indigenella Dyar and Heinrich, an endemic pest of sugarcane in southern Colombia, represents a novel host for C. flavipes. We examined the development of C. flavipes on D. indigenella and D. saccharalis, a familiar host, when larvae were stung by one, two or three wasps. Host species had no effect on parasitism success, immature parasitoid mortality, parasitoid developmental time, adult emergence, or female size. Superparasitized D. indigenella hosts yielded more cocoons, more adults, and more female wasps than those parasitized with a single sting, or from D. saccharalis hosts. However, wasp survival and longevity declined when host larvae were stung three times. Thus, D. indigenella was a more suitable host for C. flavipes when superparasitized, and appears suitable for augmentation against this emergent pest and other Diatraea species attacking sugarcane. [ABSTRACT FROM AUTHOR]

A detailed study of the static bending of micro-cantilevers has been performed for structures created from thin 3C-SiC films grown on (100) and (111) oriented silicon substrates. The biaxial stress distribution in the direction of the film normal has been evaluated based on analysis of the deformation profiles of clamped-free 3C-SiC beams of various thicknesses. Surprisingly, the obtained results clearly indicate that for as-grown samples of both studied orientations, the absolute value of the intrinsic stress increases from the interface to the surface of the film. We propose a simple analytical model of a relaxation process that explains in a quantitative way this unexpected phenomenon of stress gradient inversion. [ABSTRACT FROM AUTHOR]

The high-resolution single-photon pulsed-field-ionization zero-kinetic-energy photoelectron spectra of the X+ 2E3/2←X 1A1 transition of CH3I and CD3I have been recorded. The spectral resolution of better than 0.15 cm-1 enabled the observation of the rotational structure. CH3I+ and CD3I+ are subject to a weak Exe Jahn-Teller effect and strong spin-orbit coupling. The treatment of the rovibronic structure of the photoelectron spectra in the corresponding spin double group, C3v2(M), including the effects of the spin-orbit interaction and the vibrational angular momentum, allowed the reproduction of the experimentally observed transitions with spectroscopic accuracy. The relevant spin-orbit and linear Jahn-Teller coupling parameters of the X+ ground state were derived from the analysis of the spectra of the two isotopomers, and improved values were obtained for the adiabatic ionization energies [EI(CH3I)/hc=76931.35(20) cm-1 and EI(CD3I)/hc=76957.40(20) cm-1] and the rotational constants of the cations. Rovibronic photoionization selection rules were derived for transitions connecting neutral states following Hund's-case-(b)-type angular momentum coupling and ionic states following Hund's-case-(a)-type coupling. The selection rules, expressed in terms of the angular momentum projection quantum number P, account for all observed transitions and provide an explanation for the nonobservation of several rotational sub-bands in the mass-analyzed threshold-ionization spectra of CH3I and CD3I reported recently by Lee et al. [J. Chem. Phys. 128, 044310 (2008)]. [ABSTRACT FROM AUTHOR]

Global wheat production has remained stable in the last 20 years, benefiting from increased grain yields despite decline in harvested wheat area. Here, we conducted a comprehensive review of ca. 300 peer-reviewed studies worldwide to outline benefits of adding wheat to simple crop rotations (i.e., one to three rotational crops). We highlight the wheat's versatility for tactical in-season crop management (e.g., flexible sowing dates, crop type [winter vs spring], and nitrogen fertility) and strategic cropping system management (e.g., grazing and double-cropping) and provide evidence supporting the positive impact of wheat on the grain yield and yield stability of other rotational crops. The inclusion of wheat in simple cropping systems enhances agroecosystem diversity and improves resilience to biotic and abiotic stresses. The high carbon-to-nitrogen ratio (C:N) residue of wheat offers benefits and drawbacks on soil quality attributes, weed control, and climate change mitigation potential. The introduction of wheat to simple crop rotations can (i) interrupt pest population cycles by serving as a break crop; (ii) decrease N application requirements, thus reducing N losses, greenhouse gas emissions, soil acidification, and production costs; (iii) improve soil health and carbon sequestration; (iv) increase resource use-efficiency of the cropping system; (v) foment fauna population; and (vi) decrease variability in economic returns. This review highlights that wheat offers unique opportunities to increase diversification and foster more sustainable and resilient agroecosystems that will feed a growing global population while acting as a net carbon sink, helping to mitigate drivers of climate change. [ABSTRACT FROM AUTHOR]

Methoprene-tolerant (Met) is a putative JH intracellular receptor that transduces JH signal by activation of the inducible Krüppel homolog 1 (Kr-h1). We analyzed the gene sequences of Met and Kr-h1 and their patterns of expression in Grapholita molesta (Busck) immature and adult stages in order to better understand the roles of these primary JH responders in regulating the metamorphosis and reproduction of this global pest of fruit crops. The deduced amino acid sequences of both GmMet and GmKr-h1 were highly homologous to those of other Lepidoptera, especially the cotton bollworm, Helicoverpa armigera (Hubner) (Lepidoptera: Noctuidae). Peak expression of GmMet occurred during the last 3 to 5 d of the final instar, followed by that of GmKr-h1 , in the last 3 d of final instar. Similar patterns of GmMet and GmKr-h1 expression were detected across various tissue types in the fifth-instar larvae, with the highest expression observed in the head, followed by the epidermis, and the fat body. When expression of GmMet and GmKr-h1 was knocked down via dsRNA injection in the fifth instar, the results were increased larval mortality, abnormal pupation, delayed pupal duration, reduced adult emergence, extended preoviposition period, and reduced fecundity. We infer that both GmMet and GmKr-h1 participated in regulation of metamorphosis and reproduction in G. molesta , the former acting upstream of the latter, and could present biorational targets for novel pest control compounds. [ABSTRACT FROM AUTHOR]

Traumatic insemination (TI) can be injurious to females, and females have evolved various paragenital structures to mitigate these impacts. We examined the mating behavior of Orius insidiosus (Say) and the consequences of single and double matings for female fitness. A total of 100 virgin females (4–6-d old) were directly observed while they mated with virgin males. Some of these females were mated a second time with a different, nonvirgin male 3–5 d later, after they oviposited in sunflower stems. Females were held in isolation, fed eggs of Ephestia kuehniella Zeller, and reproductive success was tracked for 30 d. Six females died during their first copulation (6%), and another within 48 h, without laying eggs. Four percent of the females died during their second copulations. Copulations lasting less than 90 s usually did not result in successful fertilization, and duration of copula was positively correlated with egg fertility in singly-mated females. Duration of copula was more than halved in second matings, twice as variable, and negatively correlated with 30 d fecundity. Thirty-seven percent of singly-mated females and 31% of twice-mated females were infertile, with fewer than half of all females producing 88% of all eggs. We conclude that O. insidiosus females are likely monandrous in the wild, and that TI in this species is inefficient, contributing to high variation in female fitness. Thus, mating involves a significant mortality risk for females, despite their possession of complex paragenital structures that ostensibly mitigate copulatory injury. [ABSTRACT FROM AUTHOR]

1. For this study a cohort of melanic Harmonia axyridis males homozygous for the spectabilis allele was produced. These were used to produce four kinds of twice‐mated females, comprising all four permutations of melanic and non‐melanic (succinic) males. A series of 12 larvae were then reared from the first and 10th clutches of each female to compare progeny developmental phenotypes. 2. There were no effects of mating treatment on overall female reproductive performance (preoviposition period, 20‐day fecundity, or egg fertility). 3. Age‐specific maternal effects were evident in progeny developmental phenotypes; larvae of 10th clutches developed more slowly, pupation was shorter, and adults emerged at heavier weights. 4. Paternal effects were superimposed on maternal effects and affected progeny independent of their paternity; melanic males induced slower larval development and slower pupation, but only in 10th clutches and only when they mated second. 5. There was a significant three‐way interaction between male mating treatment, clutch number and progeny phenotype, indicating that progeny developmental responses to (mixed) paternal effects varied depending on their own phenotype and the time elapsed since their mother's last mating. 6. Melanic males mating second obtained a P2 advantage over succinic males, which increased from first to 10th clutch, but the reverse was not true when succinic males mated second. Thus, polyandry in H. axyridis facilitates both genetic and epigenetic competition among males while simultaneously enabling the sharing of predominant paternal effects among the progeny of different fathers. [ABSTRACT FROM AUTHOR]

Nitrogen (N) fertilization is a common agricultural practice, which, by increasing the quality of plants, also enhances their nutritional suitability for insect herbivores, creating the possibility of a cascade of N across trophic levels, from plant to herbivore to predator. We manipulated the quality of cucumber plants by fertilizing them with three different N rates (110, 160, and 210 ppm), which represented low, medium, and high N levels, respectively. Colonies of Aphis gossypii Glover (Hemiptera: Aphididae) were then reared on these plants and used as prey for adult Hippodamia variegata (Goeze) (Coleoptera: Coccinellidae) in experiments that characterized the predator's foraging behavior and functional response to different aphid densities. The nutritional content of plants and aphids was also measured. As N fertilization increased, so did the nutrient content (total energy) of aphids and this resulted in declining rates of aphid consumption by beetles at higher aphid densities. Females in the 110 N treatment, and males in all treatments, responded to aphids with a type II functional response (decelerating consumption at higher densities), but females in the 160 and 210 ppm N treatments exhibited a type III response (consuming a declining proportion of available aphids at high densities). Beetles fed aphids from the 110 N treatment consumed more prey in both assays than did those fed aphids from the 210 N treatment. Beetle searching time, handling time, and duration of digestive pauses all increased at high levels of N fertilization, especially for females. The results indicate that heavy N fertilization can increase prey nutritional quality to the point where it alters predator foraging and feeding behavior, resulting in slower rates of prey consumption and longer prey handling times. [ABSTRACT FROM AUTHOR]

Coevolutionary interactions between pathogens and their insect vectors can dramatically impact the fitness of herbivorous insects and patterns of plant disease transmission. Soybean mosaic virus (SMV) is a common disease in soybean production worldwide. Infected seed is the primary source of inoculum in fields and the virus is secondarily spread among plants by the soybean aphid, Aphis glycines Matsumura (Hemiptera: Aphididae), in a nonpersistent manner. In this study, we compared the biological fitness of A. glycines colonizing both SMV-infected and uninfected soybean plants. Aphids feeding on SMV-infected soybean seedlings were significantly smaller and lighter than those feeding on uninfected plants across life stages. SMV infection caused delayed development of aphid nymphs on soybean seedlings, but this was more than compensated by a reduction in the pre-reproductive period of apterous adults. The fecundity of A. glycines was reduced when feeding on SMV-infected seedlings, resulting in a lower reproductive rate, a longer generation time, and a slower population doubling time. A smaller proportion of aphid offspring developed into alatae when feeding on SMV-infected soybean seedling, and these took longer to mature than their counterparts on uninfected plants. We infer that SMV infection has significantly negative effects on the biological performance of A. glycines, which may be consistent with the long-term coevolution of SMV, soybean, and A. glycines in the transmission cycle of SMV. [ABSTRACT FROM AUTHOR]

The American serpentine leaf miner, Liriomyza trifolii (Burgess) (Diptera: Agromyzidae), is a perennial pest of leguminous crops in the Mediterranean region. A life table was constructed for L. trifolii infesting broad bean, Vicia faba L. in northern Egypt. Key factor analysis was used to rank sources of immature mortality over two seasons. Leaf miners had three successive generations, and a partial fourth, in each year, with peak abundance in March–April. Less than 15 and 22% of L. trifolii survived to adult in seasons one and two, respectively. The largest contributor of immature leaf miner mortality in both seasons was unknown (41.2 and 39.1% of total mortality, respectively), and likely comprised a combination of abiotic factors, parasitoid-inflicted mortality (host-feeding), and predation. Parasitism was second, contributing 36.2 and 35.6% of total mortality in the two seasons, respectively, primarily due to larval parasitism by Diglyphus isaea (Walker) (Hymenoptera: Eulophidae), and low levels of larval–pupal parasitism by Opius pallipes Wesmael (Hymenoptera: Braconidae) and Halticoptera circulus (Walker) (Hymenoptera: Pteromalidae). Residual mortality resulted from malformed pupae or failed adult emergence. Key factor analysis revealed malformation to be the major cause of pupal mortality. Sequential regression confirmed that unknown mortality and D. isaea were the top stage-specific factors, both acting on larvae. Parasitoid abundance tracked host abundance across generations, but density dependence was not observed for any mortality factor, and the magnitudes of regression slopes were small. The results indicate the potential importance of conservation biological control in management of L. trifolii, given that naturally occurring parasitoids and other biotic/abiotic factors exert significant mortality on immature leaf miners. [ABSTRACT FROM AUTHOR]

Inherited bone marrow failure syndromes (IBMFS) are caused by mutations in genes involved in genomic stability. Although they may be recognized by the association of typical clinical features, variable penetrance and expressivity are common, and clinical diagnosis is often challenging. DNAJC21, which is involved in ribosome biogenesis, was recently linked to bone marrow failure. However, the specific phenotype and natural history remain to be defined. We correlate molecular data, phenotype, and clinical history of 5 unreported affected children and all individuals reported in the literature. All patients present features consistent with IBMFS: bone marrow failure, growth retardation, failure to thrive, developmental delay, recurrent infections, and skin, teeth or hair abnormalities. Additional features present in some individuals include retinal abnormalities, pancreatic insufficiency, liver cirrhosis, skeletal abnormalities, congenital hip dysplasia, joint hypermobility, and cryptorchidism. We suggest that DNAJC21‐related diseases constitute a distinct IBMFS, with features overlapping Shwachman‐Diamond syndrome and Dyskeratosis congenita, and additional characteristics that are specific to DNAJC21 mutations. The full phenotypic spectrum, natural history, and optimal management will require more reports. Considering the aplastic anemia, the possible increased risk for leukemia, and the multisystemic features, we provide a checklist for clinical evaluation at diagnosis and regular follow‐up. [ABSTRACT FROM AUTHOR]