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Turfgrasses hosts a diverse community of predators that contribute to herbivore suppression. However, there is little evidence that predators directly consume a common turfgrass herbivore, the billbug (Sphenophorus sp.) (Coleoptera: Curculionidae). Given low rates of direct consumption by predators, prospects for strong non‐consumptive effects in billbugs were underappreciated. However, this assumed lack of non‐consumptive effects presupposes that herbivorous prey, like billbugs, can identify predators and the level of threat that they pose. Here, we examined this assumption and quantified the extent to which exposure to predators and predator cues altered the behavior (predator avoidance, feeding, and mating) of bluegrass billbug, Sphenophorus parvulus Gyllenhal. First, using a series of behavioral assays within microcosms, we exposed billbugs to predators – Pterostichus melanarius (Illiger) (Coleoptera: Carabidae), Harpalus sp. (Coleoptera: Carabidae), Philonthus sp. (Coleoptera: Staphylinidae), and Hogna sp. (Araneae: Lycosidae) – singly and in combination to measure the effect of contact with predators and potential synergy among predator species pairs. Indirect exposure to predators, predator odor, and non‐predatory arthropods were also used to measure effects of various predator cues on billbug behavior. In subsequent Y‐tube choice assays we determined whether billbugs discriminated between filtered air and predator odor to isolate chemical signaling as a potential mechanism for billbug predator detection. Direct exposure to predators increased billbug predator avoidance (up to 201%), and decreased billbug feeding (down to −78%), though no predation was observed. Similar behavioral changes were observed when billbugs were exposed indirectly to a predator, and to predator odor. In Y‐tube assays billbugs avoided predator odor, further suggesting billbugs use chemical cues to detect predator presence and that these may be a driver in their observed behavior. Our results show that billbugs exhibit strong non‐consumptive effects, even in the absence of strong direct consumptive effects. These results provide the foundation for further research concerning the role of chemical signaling in billbug predator detection. [ABSTRACT FROM AUTHOR]

Tea mosquito bug (TMB) Helopeltis theivora Waterhouse is one of the major pests in both south and north Indian tea plantations. This study was conducted to find out the behavioral responses of male TMB for developing a mass trapping technology. The study shows that TMB male’s behavioral response was high towards the thorax extract of virgin females, virgin female body wash and live virgin females. Males’ antennal responses were high towards to thorax extract of virgin females; the same sources performed well against male TMB under field conditions too. Caged virgin females provide prolonged attraction throughout their lifespan; in contrast, thorax and virgin female body extracts’ attraction rate lasted only up to 24 hr but achieved a significant attraction rate over male TMB. Caged female and thorax extract could be the effective tools for mass trapping, monitoring and controlling of TMB through mating disruption. [ABSTRACT FROM AUTHOR]

Quinones are one of the major pigment groups that provide such bright colors to feather stars (Echinodermata, Crinoidea). These secondary metabolites also act as defensive molecules rendering crinoids unpalatable and repellent to other organisms. However, feather stars are usually associated with numerous symbiotic organisms, amongst which the ectocommensal snapping shrimp Synalpheus stimpsonii. We investigated the chemical stimulus allowing host selection in S. stimpsonii through the combination of behavioral tests, chemical extractions, and mass spectrometry analyses. The individuals of S. stimpsonii used in the experiments were sampled around the Great Reef of Toliara (Madagascar) where they are found in association with two crinoid species: Comanthus wahlbergii and Phanogenia distincta. The chemical attractiveness of the two crinoid hosts and a non-host species, Cenometra bella, was tested in an olfactometer. The three crinoids produced attractive kairomones allowing the snapping shrimp to recognize them. Mass spectrometry analyses on purified extracts of P. distincta revealed the presence of three different anthraquinones (rhodoptilometrin, comantherin, and a new crinoid anthraquinone). Compared to the existing literature, this anthraquinonic cocktail is specific to P. distincta. When these extracts were injected in the olfactometer, they triggered similar attracting behavior suggesting that crinoid anthraquinones are kairomones allowing host selection for S. stimpsonii. This hypothesis is also supported by the fact that shrimps were chemically attracted by pure commercial anthraquinones. In addition to their traditional defensive role (allomones), anthraquinones would, therefore, also function as kairomones, maintaining the symbiosis between S. stimpsonii and its crinoid hosts. [ABSTRACT FROM AUTHOR]

Chemosensory proteins (CSPs) have great contributions in performing diverse functions in insects. However, physiological appraisal of chemosensory protein genes still remains elusive in insects. We studied expression patterns and binding affinities of MsepCSP14, a chemosensory protein, in Mythimna separata. The distinct functions of MsepCSP14 were validated by employing different molecular techniques. The MsepCSP14 had high resemblance of sequence with chemosensory proteins of other insect family members. The MsepCSP14 expression was higher in antennal tissues of females than other tissues. Fluorescence binding assay validated that binding of nine out of 21 ligands to MsepCSP14 was higher at pH 7.4 than at pH 5.0. Three dimensional modeling (3D) and docking analysis predicted that amino acid residues of MsepCSP14 were involved in binding of compounds, and behavior assay displayed that adults of M. separata considerably responded to four volatiles from compounds demonstrating strong binding ability to MsepCSP14. Results of the present study suggest that MsepCSP14 is likely to mediate chemosensory functions in M. separata. [ABSTRACT FROM AUTHOR]

[Display omitted] • The LED light at UV or near-UV can enhance the establishment of natural enemies. • Inter-strain variation in attraction to wavelengths was observed in O. laevigatus. • The 385 nm wavelength was the most attractive light wavelength to O. laevigatus. Inter-strain variation in attraction to specific LED wavelengths has been studied previously. Here, we report on differences in attraction of two commercialized strains (Biobest and Koppert) of Orius laevigatus to 10 or 11 different LED wavelengths. We found a significant difference in attraction patterns among the tested wavelengths between the two insect strains; for the Biobest strain, attraction was the highest in 365 and 385 nm wavelengths, while for the Koppert strain, it was the highest in 365, 385, 395, and 405 nm wavelength. As both strains showed highest attraction rate at a wavelength of 385 nm, lights with this output could be used in field pest management strategies. [ABSTRACT FROM AUTHOR]

Flame atmospheric pressure chemical ionization (FAPCI) combined with negative electrospray ionization (ESI) mass spectrometry was developed to detect the ion/molecule reactions (IMRs) products between nitric acid (HNO) and negatively charged amino acid, angiotensin I (AI) and angiotensin II (AII), and insulin ions. Nitrate and HNO-nitrate ions were detected in the oxyacetylene flame, suggesting that a large quantity of nitric acid (HNO) was produced in the flame. The HNO and negatively charged analyte ions produced by a negative ESI source were delivered into each arm of a Y-shaped stainless steel tube where they merged and reacted. The products were subsequently characterized with an ion trap mass analyzer attached to the exit of the Y-tube. HNO showed the strongest affinity to histidine and formed (M-H+HNO) complex ions, whereas some amino acids did not react with HNO at all. Reactions between HNO and histidine residues in AI and AII resulted in the formation of dominant [M-H+(HNO)] and [M-H+(HNO)] ions. Results from analyses of AAs and insulin indicated that HNO could not only react with basic amino acid residues, but also with disulfide bonds to form [M-3H+(HNO)] complex ions. This approach is useful for obtaining information about the number of basic amino acid residues and disulfide bonds in peptides and proteins. [ABSTRACT FROM AUTHOR]

Highlights: [•] We studied the impact of cover crop mulch on imported cabbageworm biocontrol. [•] Cover crop mulch species affected cabbageworm and Cotesia rubecula abundance. [•] Increased parasitoid abundance did not result in increased parasitism in the field. [•] Mulch interfered with the short-range host finding odor cues of Cotesia rubecula. [•] Small natural enemies provide biological control of the imported cabbageworm. [ABSTRACT FROM AUTHOR]

While brain lateralization is widely studied for vertebrates, only a few studies have been performed on insects. In the present research, we investigated the behavior of the common American cockroach, Periplaneta americana, to determine if such lateralization is evident through their decision making process. The roaches were allowed to run through a y-tube and make a decision on which direction to take. Vanilla and ethanol were randomly placed at the ends of the y-tube to entice the roaches to reach the end of the tubes. Tests were repeated by severing one antenna on each roach in different configurations which were expected to alter the decision of the insect. Through a simple statistical analysis we determined that the odors of vanilla and ethanol play an insignificant role in the decision making. We found that injury to the antenna indeed affected their decision, However, similar injury to either antenna showed an innate bias for turning right. Our research supports the hypothesis that Periplaneta americana is right-side dominated in their tactile and odor senses. [ABSTRACT FROM AUTHOR]

Pioneer herbivorous insects may find their host plants through a combination of visual and constitutive host-plant volatile cues, but once a site has been colonized, feeding damage changes the quantity and quality of plant volatiles released, potentially altering the behavior of conspecifics who detect them. Previous work on the pepper weevil, Anthonomus eugenii Cano (Coleoptera: Curculionidae), demonstrated that this insect can detect and orient to constitutive host plant volatiles released from pepper [ Capsicum annuum L. (Solanaceae)]. Here we investigated the response of the weevil to whole plants and headspace collections of plants damaged by conspecifics. Mated weevils preferred damaged flowering as well as damaged fruiting plants over undamaged plants in a Y-tube olfactometer. They also preferred volatiles from flowering and fruiting plants with actively feeding weevils over plants with old feeding damage. Both sexes preferred volatiles from fruiting plants with actively feeding weevils over flowering plants with actively feeding weevils. Females preferred plants with 48 h of prior feeding damage over plants subjected to weevil feeding for only 1 h, whereas males showed no preference. When attraction to male- and female-inflicted feeding damage was compared in the Y-tube, males and females showed no significant preference. Wind tunnel plant assays and four-choice olfactometer assays using headspace volatiles confirmed the attraction of weevils to active feeding damage on fruiting plants. In a final four-choice olfactometer assay using headspace collections, we tested the attraction of mated males and virgin and mated females to male and female feeding damage. In these headspace volatile assays, mated females again showed no preference for male feeding; however, virgin females and males preferred the headspace volatiles of plants fed on by males, which contained the male aggregation pheromone in addition to plant volatiles. The potential for using plant volatile lures to improve pepper weevil monitoring and management is discussed. [ABSTRACT FROM AUTHOR]

The lacewing Chrysopa cognata, one of the principal predators of aphids in Korea, was tested for responses to the aphid sex pheromone components (4a S,7 S,7a R)-nepetalactone and (1 R,4a S,7 S,7a R)-nepetalactol and the aphid alarm pheromone ( E)-β-farnesene. Electroantennogram responses were obtained to the sex pheromone components but not to ( E)-β-farnesene. The sex pheromone components were attractive in a Y-tube olfactometer assay and in field trials with water traps, but no attraction was observed to ( E)-β-farnesene. [ABSTRACT FROM AUTHOR]