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The liquid fluorescent material SmartWater® has recently been reported as an effective external mark for arthropods. In this study, we examined the behavioral effects of the SmartWater marker on Lygus hesperus (Knight) (Hemiptera: Miridae). Specifically, we quantified the roaming and flight characteristics of unmarked, water-marked, and SmartWatermarked specimens. The results showed no significant differences in L. hesperus roaming and flight speeds, distances, and durations between the marking treatments. The results reported here and from previous research show the SmartWater product has enormous potential for mark-release-recapture type research. [ABSTRACT FROM AUTHOR]

Mark‐release‐recapture studies require the application of a taggant to the arthropod under investigation before release at the study site so that recaptured specimens are identifiable. This mark must not affect the dispersal or foraging behaviour of the targeted organism. In this study, groups of Eretmocerus eremicus Rose and Zolnerowich (Hymenoptera: Aleyrodidae), a whitefly parasitoid, were marked externally with fluorescent dust or a liquid protein, or internally with a protein incorporated in their diet. Subsequently, the mark treatments' effects on foraging behaviour were compared with unmarked parasitoids. For the most part, marked specimens behaved similarly to their unmarked counterparts. However, there was an increase in host feeding, probing, and grooming activities exhibited by parasitoids exposed to certain mark treatments. [ABSTRACT FROM AUTHOR]

A marking and recapture sampling method was developed that shows promise for studying the dispersal behavior of small and delicate arthropods. Adult sweetpotato whiteflies, Bemisia tabaci (Gennadius) (Hemiptera: Aleyrodidae), were externally marked with a liquid fluorophore that glows brightly under ultraviolet (UV) light. Then, a series of simulated recapture tests on fluorophore‐marked whiteflies using yellow sticky cards were conducted. The marked whiteflies captured on the sticky cards were detected by direct visual inspection of photographs taken of the cards under white light and UV light. Whitefly counts taken under white and UV light were almost identical, implying high marking efficacy and visual distinctiveness. These results suggest that this fluorophore marking and sampling method could eliminate the tedious task of removing specimens from sticky cards and examining them individually for the presence of a mark. [ABSTRACT FROM AUTHOR]

We evaluated a method for marking arthropods that could serve as a valuable tool for mark‐release‐recapture dispersal research. The taggants tested consisted of three liquid fluorophores labeled cartax green, magenta, and orange. The manufacturer markets these fluorescent markers as forensic theft deterrents. Specimens of 16 genera of arthropods were externally marked with either one of the colored fluorophores or with water (negative control treatment). The specimens were then qualitatively and quantitatively inspected for fluorescence 24 h later. For the qualitative analysis, three independent observers scored each specimen by direct observation for the presence of a fluorescent mark. The specimens were scored using a portable ultraviolet (UV) tube lantern and a specialized NIGHTSEA‐brand LED UV light. The three fluorophores were readily detected on many but not all the species examined, regardless of the type of UV light used. Moreover, the NIGHTSEA LED light yielded fewer false‐negative observer errors than the lantern. Each specimen's fluorescence was measured with an automated dual‐wavelength microplate fluorometer for the quantitative analysis. Overall, the quantitative analysis was very reliable at detecting fluorescence on a few taxa [e.g., Bemisia tabaci (Gennadius) (Hemiptera: Aleyrodidae), Chrysoperla spp. (Neuroptera: Chrysopidae)], effective on most taxa, and unreliable on several others [e.g., Collops vittatus (Say) (Coleoptera: Melyridae), Geocoris spp. (Hemiptera: Geocoridae), Mecaphesa celer (Hentz) (Araneae: Thomisidae)]. The cartax green marker was more readily detected than the magenta and orange markers with both visual and automated detection. Overall, the results show that these fluorophores could be effective markers for many arthropod species. [ABSTRACT FROM AUTHOR]

We examined the feasibility of externally marking insects with the liquid fluorescent forensic theft deterrent, SmartWater (SmartWater CSI, LLC.). We sprayed captive Lygus hesperus (Knight) (Hemiptera: Miridae), Bemisia tabaci (Gennadius) (Hemiptera: Aleyrodidae), and Hippodamia convergens Guérin-Méneville (Coleoptera: Coccinellidae) with SmartWater fluorophore, and then qualitatively examined them for fluorescence by visual inspection under ultraviolet (UV) light and quantitatively measured them with a multiwavelength microplate fluorometer. The results indicate that this product has enormous potential as a taggant for L. hesperus and B. tabaci. However, the marking efficiency for H. convergens was only adequate. The advantages and limitations of using SmartWater as a biological marker for arthropod mark-release-recapture research are discussed. [ABSTRACT FROM AUTHOR]

A molecular gut analysis technique is described to identify predators of Lygus hesperus (Knight), a significant pest of many crops. The technique is unique because it can pinpoint which life stage of the pest was consumed. Sentinel egg masses designed to mimic the endophytic egg-laying behavior of L. hesperus were marked with rabbit serum, while third instar and adult L. hesperus were marked with chicken and rat sera, respectively. Then, the variously labeled L. hesperus life stages were introduced into field cages that enclosed the native arthropod population inhabiting an individual cotton plant. After a 6-h exposure period, the predator assemblage, including the introduced and native L. hesperus population, in each cage were counted and had their gut contents examined for the presence of the variously marked L. hesperus life stages by a suite of serum-specific enzyme-linked immunosorbent assays (ELISA). The whole-plant sampling scheme revealed that Geocoris punticpes (Say) and Geocoris pallens Stal (Hemiptera: Geocoridae) and members of the spider complex were the numerically dominant predator taxa in the cotton field. The gut content analyses also showed that these two taxa appeared to be the most prolific predators of the L. hesperus nymph stage. Other key findings include that Collops vittatus (Say) (Coleoptera: Melyridae) and Solenopsis xyloni McCook (Hymenoptera: Formicidae) appear to be adept at finding and feeding on the cryptic L. hesperus egg stage, and that L. hesperus , albeit at low frequencies, engaged in cannibalism. The methods described here could be adapted for studying life stage-specific feeding preferences for a wide variety of arthropod taxa. [ABSTRACT FROM AUTHOR]

Alfalfa, Medicago sativa L. (Fabaceae), is a highly preferred host plant of Lygus spp. (Hemiptera: Miridae). As such, intercropping alfalfa trap‐crops in strawberry production can serve as a sink for both Lygus (primarily Lygus hesperus Knight) and its natural enemies. Here we investigated the population dynamics and dispersal characteristics of the generalist predator complex in strawberry fields with alfalfa trap‐crops spaced 50 rows (62 m) apart. Predator abundance was determined by counting six focal taxa collected from strawberry and alfalfa. The data revealed that Orius spp. (Hemiptera: Anthocoridae) were the numerically dominant predator taxa, comprising 84% of the focal predator population. In general, the population densities obtained for the various taxa throughout this agroecosystem were unexpectedly uniform. Predator movement from a central alfalfa trap‐crop row was determined using a protein mark–capture procedure. Most protein‐marked predator specimens were collected less than 2 m from the centrally marked alfalfa row, indicating that the trap‐crop often produces a predator sink. Results suggest that alfalfa is a useful cultural (trap‐cropping) and a biological (refuge for natural enemies) control tactic for managing Lygus spp. in strawberries. [ABSTRACT FROM AUTHOR]

Having an effective method to track movement of arthropods in nature is essential for any mark-release-recapture (MRR) or mark-capture (MC) type experiment. A simple protein immunomarking technique (PIT) was described over a quarter of a century ago that has since been proven to be a highly useful and versatile tool for tracking arthropod dispersal patterns. The PIT consists of tagging arthropods with a specific protein. In turn, recaptured arthropods are examined for the presence of the protein tag by a highly sensitive and specific enzyme-linked immunosorbent assay. In this article, I review the progression of the PIT procedure, provide guidelines for conducting a successful PIT (MRR or MC) dispersal study, and highlight some of the ways this procedure has been adapted to study the dispersal patterns of a wide variety of arthropod species. My goal is that this information will provide researchers with the motivation to develop even more creative uses for the PIT. [ABSTRACT FROM AUTHOR]

The analysis of arthropod feeding activity is often determined by using species-specific postmortem gut content polymerase chain reaction and enzyme-linked immunosorbent assays (ELISA). Such mono-specific assays require time, resources, and technical expertise to develop for the food item (usually a pest insect species) that is the target of the investigation. A generic predator gut analysis method was described over a quarter of a century ago that does not require the development of a species-specific gut assay. This generic method remained in relative obscurity until about a decade ago. Recently, it has been used to study a wide range of arthropod feeding activities, such as carnivory, herbivory, scavenging, and other feeding interactions. For this review, I have coined this method as the universal food immunomarking technique (UFIT). The UFIT consists of tagging food items (i.e. prey, foliage, carrion, etc.) with a specific protein. In turn, the gut contents of foraging arthropods are examined for the presence of protein-marked food items by a standardized protein-specific sandwich ELISA. In this article, I give examples of the benefits of the UFIT gut assay approach over prey-specific gut assay approaches and tips on conducting a successful UFIT experiment, and provide examples of how it has been adapted to study a wide variety of arthropod feeding behaviors. My goal is to make researchers aware of another valuable tool in the gut analysis toolbox. [ABSTRACT FROM AUTHOR]

Wild host plants in the landscape surrounding fruit farms may significantly influence the movement and population of the polyphagous and invasive pest Drosophila suzukii.Across 2 years, we sampled wild hosts adjacent to 10 blueberry farms in Michigan, U.S.A. We found five commonly infested wild fruits.Honeysuckle was a particularly abundant early season reproductive host. Consequently, six blueberry farms with honeysuckle at the margin were evaluated further. At each farm, nonhost plants and honeysuckle were monitored for larval and adult D. suzukii. The season‐long abundance of D. suzukii adults and early‐season infestation was highest near and within honeysuckle.In 2017, we tracked the movement of D. suzukii between honeysuckle and blueberries in early and late season using a protein immunomarking technique. Of the 1881 flies captured in our study, 7.1% were marked and their distribution pattern was even throughout the farm. Moreover, early season flies were less likely to remain in the marked host compared with late season flies.The findings of the present study highlight the importance of wild hosts on local pest pressure from D. suzukii and suggest that wild host management should be considered as part of integrated strategies for reducing the economic impacts of this pest. [ABSTRACT FROM AUTHOR]

Wolf spiders (Araneae: Lycosidae) are abundant ground predators in cotton fields that can provide important pest management services. These spiders can kill and consume larvae of the cotton bollworm Helicoverpa spp. (Lepidoptera: Noctuidae) that survive foraging on Bt cotton and descend from the plant to pupate in the soil. To determine predation frequency by wolf spiders in a Bt cotton field, we indirectly assessed predation using Helicoverpa spp. larvae marked with rabbit immunoglobulin G (IgG; “immunomarking”), and carried out capture-mark-recapture surveys to assess the likelihood of recapturing spiders. A laboratory feeding study with IgG-marked larva demonstrated that IgG is readily detected in spiders for up to 72 h after feeding. Following the release of IgG-marked larvae in a cotton field edge, 2.1% of spiders collected tested positive for the presence of IgG, providing indirect evidence of predation. A capture-mark-recapture survey revealed that spiders had opportunity to encounter IgG-marked larvae released along field edges, but only 6.7% of the spiders were recaptured, likely reflecting high spider mobility. In field feeding arenas, all three commonly encountered wolf spider species ( Tasmanicosa leuckartii, Hogna crispipes, Hogna kuyani ) ate Helicoverpa spp. larvae. These studies suggest that the low likelihood of spider recapture, and not prey rejection, is the most likely explanation for the low proportion of field-collected spiders testing positive for IgG marked prey remains, and that the frequency of IgG detection in spiders likely underestimated the frequency of predation events. We conclude that use of prey immunomarking together with capture-mark-recapture surveys can provide a powerful tool for assessing the effect of a predator on a prey species under field conditions. [ABSTRACT FROM AUTHOR]

A study was conducted that compared the effectiveness of a sweepnet versus a vacuum suction device for collecting arthropods in cotton. The study differs from previous research in that body-mounted action cameras (B-MACs) were used to record the activity of the person conducting the arthropod collections. The videos produced by the B-MACs were then analyzed with behavioral event recording software to quantify various aspects of the sampling process. The sampler's speed and the number of sampling sweeps or vacuum suctions taken over a fixed distance (12.2 m) of cotton were two of the more significant sampling characteristics quantified for each method. The arthropod counts obtained, combined with the analyses of the videos, enabled us to estimate arthropod sampling efficiency for each technique based on fixed distance, time, and sample unit measurements. Data revealed that the vacuuming was the most precise method for collecting arthropods in the relatively small cotton research plots. However, data also indicates that the sweepnet method would be more efficient for collecting most of the cotton-dwelling arthropod taxa, especially if the sampler could continuously sweep for at least 1 min or ≥80 m (e.g., in larger research plots). The B-MACs are inexpensive and non-cumbersome, the video images generated are outstanding, and they can be archived to provide permanent documentation of a research project. The methods described here could be useful for other types of field-based research to enhance data collection efficiency. [ABSTRACT FROM AUTHOR]

Conventional prey-specific gut content ELISA (enzyme-linked immunosorbent assay) and PCR (polymerase chain reaction) assays are useful for identifying predators of insect pests in nature. However, these assays are prone to yielding certain types of food chain errors. For instance, it is possible that prey remains can pass through the food chain as the result of a secondary predator (hyperpredator) consuming a primary predator that had previously consumed the pest. If so, the pest-specific assay will falsely identify the secondary predator as the organism providing the biological control services to the ecosystem. Recently, a generic gut content ELISA was designed to detect protein-marked prey remains. That assay proved to be less costly, more versatile, and more reliable at detecting primary predation events than a prey-specific PCR assay. This study examines the chances of obtaining a 'false positive' food chain error with the generic ELISA. Data revealed that the ELISA was 100% accurate at detecting protein-marked Lygus hesperus Knight ( Hemiptera: Miridae) remains in the guts of two (true) primary predators, Hippodamia convergens Guérin- Méneville ( Coleoptera: Coccinellidae) and Collops vittatus ( Say) ( Coleoptera: Melyridae). However, there was also a high frequency (70%) false positives associated with hyperpredators, Zelus renardii Kolenati ( Hemiptera: Reduviidae), that consumed a primary predator that possessed protein-marked L. hesperus in its gut. These findings serve to alert researchers that the generic ELISA, like the PCR assay, is susceptible to food chain errors. [ABSTRACT FROM AUTHOR]

The desert-adapted crops vernonia ( Centrapalus pauciflorus ), lesquerella ( Physaria fendleri ), and camelina ( Camelina sativa ) are being grown in the arid southwestern USA as potential feedstock for biofuel and/or other environmentally friendly products. A plant feeding choice test was conducted to determine the relative attractiveness of these three “new” crops to a possible insect pest, Lygus hesperus Knight. Adult L. hesperus were readily observed feeding or resting on the flowering structures of each plant type, but they were seen most often on vernonia and least often on camelina. Lygus hesperus readily deposited their eggs on each plant species, but again, the greatest amount of egg deposition was found on vernonia and the least on camelina. These studies indicate that L. hesperus might pose a threat to the production of these new crops. Moreover, the commercial expansion of these crops could significantly alter the population dynamics of the existing arthropod community. New challenges for managing this pest during regional crop production changes are discussed. [ABSTRACT FROM AUTHOR]

Omnivorous predators are key contributors to biocontrol, but the relative importance and interactive effects of ecological variables (e.g., habitat and prey- or plant-based foods) that impact their colonization, abundance, and/or function in crop fields are poorly understood. Here, we use immuno-marking to examine both activity density and consumption by omnivorous ground beetles in response to experimentally manipulated cover, weed seeds, and invertebrate prey. Vegetative cover increased per-capita seed predation by 73% compared with bare plots, validating existing correlative evidence that cover crops facilitate weed biocontrol. Interestingly, beetles responded differently to the main effects of seeds and prey. In both years, early season seed presence increased activity-density by 77%, while prey availability never influenced beetle activity. These data suggest that within-field habitat manipulation strategies such as cover crops improve biocontrol, not only by promoting increased activity of omnivores, but also by facilitating their function as seed predators on an individual-level. [ABSTRACT FROM AUTHOR]

Various types of protein-spray solutions have proven effective for externally tagging arthropods for mark-release-recapture and mark-capture type dispersal research. However, there is concern that certain standardized arthropod collection methods, such as sweep netting, might lead to high incidences of protein transfer from field-marked to unmarked arthropods during sample collection and sample handling. Native arthropods were collected in sweep nets from a field of alfalfa, Medicago sativa L. ( Fabaceae). The nets also contained 10 egg white-, 10 bovine milk-, 10 soy milk-, and 10 water (control)-marked Hippodamia convergens Guérin- Méneville ( Coleoptera: Coccinellidae) that were visually distinguishable by a yellow, white, green, and blue dot, respectively. The plant debris and arthropods from each sweep net collection were then placed into either a paper or a plastic bag and frozen for storage. The contents of each sweep net sample were thawed and the color-coded H. convergens and field-collected arthropods were examined for the presence of each protein by an egg white (albumin), bovine milk (casein), and soy milk (soy trypsin) enzyme-linked immunosorbent assay ( ELISA). Data revealed that only 0.67, 0.81, and 0% of the field-collected unmarked arthropods acquired an egg white, bovine milk, and soy milk mark, respectively. ELISA results also showed that all the egg white-marked H. convergens retained their mark, but 22.1% of the bovine milk-marked and 5.1% of the soy milk-marked H. convergens (color-coded beetles) lost their mark during the collection and sample handling processes. [ABSTRACT FROM AUTHOR]

Highlights: [•] Retention rates of augmented P. maculiventris were increased in optimal weather. [•] Optimal weather+aggregation pheromone further reduced P. maculiventris emigration. [•] Semiochemical lures elicited point-source attraction of predators. [•] Augmented and wild P. maculiventris contributed to pest control services. [•] Parasitoids (Diptera and Hymenoptera) were attracted to both pheromone and HIPVs. [ABSTRACT FROM AUTHOR]

Marking biological control agents facilitates studies of dispersal and predation. This study examines the effect of a biological solvent, dimethyl sulfoxide ( DMSO), on retention of immunoglobulin G (IgG) protein solutions applied to Diorhabda carinulata ( Desbrochers) ( Coleoptera: Chrysomelidae), an important biological control agent of saltcedar, either internally by feeding them protein-labeled foliage or externally by immersing them in a protein solution. In addition, we determined whether internally or externally marked DMSO-IgG labels could be transferred via feeding from marked D. carinulata to its predator, Perillus bioculatus ( Fabricius) ( Heteroptera: Pentatomidae). The presence of rabbit and chicken IgG proteins was detected by IgG-specific enzyme-linked immunosorbent assays ( ELISA). DMSO-IgG treatments showed greater label retention than IgG treatments alone, and this effect was stronger for rabbit IgG than for chicken IgG. Fourteen days after marking, beetles immersed in rabbit IgG showed 100% internal retention of label, whereas beetles immersed in chicken IgG showed 65% internal retention. Immersion led to greater initial (time 0) label values, and longer label retention, than feeding beetles labeled foliage. The DMSO-IgG label was readily transferred to P. bioculatus after feeding on a single marked prey insect. This investigation shows that addition of DMSO enhances retention of IgG labels, and demonstrates that protein marking technology has potential for use in dispersal and predator-prey studies with D. carinulata. Moreover, our observation of P. bioculatus feeding on D. carinulata is, to our knowledge, a new predator-prey association for the stink bug. [ABSTRACT FROM AUTHOR]

Understanding predator-prey interactions of the arthropod community in any given ecosystem is essential in pinpointing the biological control services provided by natural enemies., Hence, four prey-specific polymerase chain reaction (PCR) assays were developed to analyse the gut contents of the cotton predator community. The four targeted prey included a herbivore/pest, omnivore/pest, omnivore/beneficial, and carnivore/beneficial., First, prey retention tests were conducted to determine how long a prey item of each target species could be detected in a predator after ingestion. The assays yielded highly variable inter-assay and intra-assay prey detection efficiencies., Then, a multifaceted field study was conducted to quantify the population dynamics of the cotton predator assemblage and to assess the frequencies of predation that each predator species exhibited on the targeted prey. In total, 1794 predators, representing 17 arthropod families, were collected over two seasons using both sweep net and whole plant sampling procedures., The predator gut assays showed that there was substantial inter-guild predation occurring on the herbivore/pest, Bemisia tabaci ( Gennadius); moderate intra-guild predation on the omnivore/pest, Lygus spp. ( Lygus lineolaris ( Palisot de Beauvois), L. hesperus Knight, and L. elisus Van Duzee) and the omnivore/beneficial, Geocoris spp. ( Geocoris punctipes ( Say), and G. pallens Stål); and very little intra-guild predation on the carnivore/beneficial, Collops vittatus ( Say)., The gut assays also revealed that DNA of the targeted pests, B. tabaci and Lygus spp., were found more frequently in insect predators than spiders; whereas there were no significant differences in predation between the predatory insects and spiders for the beneficial insects, Geocoris spp. and C. vittatus., Finally, there was a significantly higher frequency of predation events recorded for B. tabaci, Lygus spp., and Geocoris spp. in the sweep net samples. This indicates that the method of collection might influence the interpretation of the gut assay results. [ABSTRACT FROM AUTHOR]

The article focuses on a research conducted in order to quantify the dispersal patterns of the honey bee Apis mellifera in an alfalfa seed production area located in Fresno County, California that contains both Roundup Ready and conventional alfalfa. It discusses the placement of honey bee self-marking devices loaded with distinct powdered markers at the entrances of 112 honey bee hives. The study revealed the extent of pollen-mediated gene flow from Roundup Ready to conventional alfalfa.

Marking biological control agents facilitates studies of dispersal and predation. This study examines the feasibility of marking the various life stages of a weed biological control agent, Diorhabda carinulata (Desbrochers) (Coleoptera: Chrysomelidae), by submersion in rabbit or chicken immunoglobulin G (IgG) protein solutions. We determined whether externally applied IgGs are effective labels of the various lifestages, whether IgGs can be retained between D. carinulata lifestages, and to what extent abiotic factors associated with field conditions mediate label retention. The presence of the labels on the various lifestages of the beetles was detected by IgG-specific enzyme-linked immunosorbent assays. Duration of each immunolabel was measured on eggs and larvae in laboratory studies and on adults in laboratory and field studies. For adults, both labels showed high (>80%) retention for ca. 14 days after marking under field and laboratory conditions. Temperature and type of label (rabbit or chicken) had only a minimal effect on marker retention. Externally marked eggs exhibited high (100%) retention for both proteins over the entire duration of the egg stage. Interestingly, some larvae emerging from externally labeled eggs contained both external and internal IgG marks. To our knowledge, this is the first case of an IgG being transferred from the egg to larva of an insect. Age of eggs at the time of label application affected the intensity of the external label on neonates. For instance, larvae that emerged from eggs that were >1 day old when labeled exhibited stronger label retention than larvae that emerged from eggs that were 1 day old when labeled. For larvae, retention of rabbit IgG was greater than retention of chicken IgG. Label retention declined as larvae aged; larvae >3 days old retained significantly less label than did neonate larvae. Both IgG labels were retained from the first to second instar, but at a very low rate of <10%. Overall, our study demonstrates that protein-marking technology has potential for use in studies of dispersal and predator-prey associations for D. carinulata. [ABSTRACT FROM AUTHOR]

Abstract: A new method for post-mortem quantification of predation on prey items marked with protein antigens is described. First, short-term protein marking retention tests were conducted on the targeted prey, immature Lygus hesperus Knight (Heteroptera: Miridae). Chicken IgG, rabbit IgG, or soy milk proteins were readily detectable by a suite of protein specific enzyme-linked immunosorbent assays (ELISA) on the L. hesperus. Then, predator gut content assays were conducted on chewing and piercing–sucking type predators that consumed a 3rd instar L. hesperus marked with rabbit IgG. The rabbit IgG gut content ELISA detected the marked prey in the vast majority of both types of predators for up to 24h after feeding. Finally, field cage studies were conducted to quantify predation rates of the natural cotton predator assemblage on protein marked L. hesperus nymphs. Each 4th instar L. hesperus marked with rabbit IgG, chicken IgG, and soy milk was released into one of 360 field cages containing a cotton plant and the natural population of predators. After 7h, each caged plant was pulled from the field, the number of predaceous arthropods in each cage were tallied, and each individual predator was assayed for the presence of marked prey by a suite of protein-specific ELISAs. A procedural error with the soy mark application negated the anti-soy ELISA data, but the anti-rabbit IgG and anti-chicken IgG ELISAs pinpointed exactly which predators preyed on the IgG marked nymphs. The protein-specific gut ELISAs revealed that various members of Araneae, Heteroptera, and Coleoptera were the most common predators of the marked prey items. In all, 74 predation events were recorded in the guts of the 556 predators encountered in the field cages. Of these 26, 23, and 14 marked individuals were eaten by various members of Araneae, Heteroptera, and Coleoptera, respectively. This study verifies that prey immunomarking is a simple, versatile, and effective method for quantifying predation rates on L. hesperus. [Copyright &y& Elsevier]

The article discusses a study concerning the diet selection exhibited at different life stages of two tarnished plant bugs namely Lygus hesperus and Lygus lineolaris. It is stated that feeding activities of 422 insects on copious amounts of cotton leaf disk and sweetpotato whitefly, Bemisia tabaci was observed for 1 hour each. It further states that juvenile L. hesperus showed more predaceous behavior than L. lineolaris on whitefly's nymphs, adults and eggs.

A series of studies was conducted to test methods for marking a wide variety of arthropods with inexpensive proteins for mark-capture dispersal research. The markers tested included egg albumin protein in chicken egg whites and casein protein in bovine milk. The first study qualified the effectiveness of the two marks on more than 50 arthropod species inhabiting cotton via two application procedures. The application methods included: (1) a topical plus residue protein application, and (2) a residue-only protein application. Both protein marks, regardless of the method of application, were readily retained on the arthropod assemblage over the duration of the study. The second study determined how rapidly insects acquire chicken egg albumin protein after contact exposure to cotton tissue sprayed with an egg whites solution. Under laboratory conditions, the vast majority of adult Hippodamia convergens Guérin-Méneville (Coleoptera: Coccinellidae) and Lygus hesperus Knight (Heteroptera: Miridae) acquired the mark after 5 min, and immature Trichoplusia ni (Hübner) (Lepidoptera: Noctuidae) acquired the marker after 40 min. The third study determined how rapidly H. convergens and L. hesperus acquire bovine casein protein after contact exposure to either alfalfa, Medicago sativa L. (Fabaceae), or lesquerella, Lesquerella fendleri (Watson) (Brassicaceae), plants sprayed with a bovine milk solution. These insects rapidly acquired the casein mark from the plant residue under field conditions. A final study determined how long H. convergens retain casein protein after 24-h exposure to alfalfa and lesquerella plants containing a 7-day-old residue of bovine milk. Approximately 95% of the H. convergens maintained the casein mark for 2 days after removal from each type of plant. [ABSTRACT FROM AUTHOR]

The efficacy of two different antigen–antibody combinations to detect predation on eggs of Helicoverpa armigera (Hübner) (Lepidoptera: Noctuidae) was compared. The first method was an indirect enzyme-linked immunosorbent assay (ELISA) using monoclonal antibody-based gut content analysis that detects H. armigera egg protein. The second method was a sandwich ELISA that detects an exotic protein [rabbit immunoglobulin G (IgG)] applied as an external marker to H. armigera eggs. The target predators were the predatory beetles Dicranolaius bellulus (Guerin-Meneville) (Coleoptera: Melyridae) and Hippodamia variegata (Goeze) (Coleoptera: Coccinellidae). Beetles were fed with H. armigera eggs that had been marked with rabbit IgG and then held at various intervals after prey consumption. Each individual beetle was then assayed by both ELISA techniques to identify the prey remains in their guts. The two ELISA methods were further tested on field-collected predators. Specifically, protein-marked egg masses were strategically placed in a cotton field. Then, predators from surrounding cotton plants were collected at various time intervals after the marked eggs were exposed and assayed by both ELISAs to detect the frequency of predation on the marked eggs. The rabbit IgG-specific sandwich ELISA had a higher detection rate than the H. armigera-specific indirect ELISA under controlled and field conditions for both predator species. Moreover, a greater proportion of field-collected D. bellulus tested positive for predation than H. variegata. The advantages and disadvantages of using prey-marking ELISAs instead of pest-specific ELISA assays are discussed. [ABSTRACT FROM AUTHOR]

A series of bioassays were conducted to determine the response of adult western tarnished plant bugs, Lygus hesperus Knight (Heteroptera: Miridae), to artificial diets containing potassium chloride (KCl). We first examined the feeding behavior of L. hesperus by direct observation in a no-choice diet feeding arena. We observed a total of 22 Lygus feeding events lasting an average of 411 ± 64 s on the control artificial diet and only three feeding events lasting an average of 11 ± 3 s on the KCl-treated diet. We then conducted several multiple diet choice bioassays to determine the feeding response of L. hesperus when exposed simultaneously to five artificial diet treatments containing different amounts of KCl. For the first bioassay, we used standard clear parafilm diet packets and for the second bioassay we used dark green parafilm diet packets to hold the various diet treatments. Regardless of the diet packet color, L. hesperus overwhelmingly selected the 0% KCl diet treatment over diets containing 3, 6, 9, or 12% KCl. The third and fourth multiple diet choice bioassays were identical to the first bioassay, except that concentrations of the KCl-treated diets were reduced. Lygus hesperus consistently selected the control diet over all diets containing more than 0.5% KCl. However, when the concentration of KCl in the diet was reduced to ≤0.4%, there were no significant differences in feeding activity exhibited by L. hesperus. Finally, to determine if the addition of KCl to the diet influenced their upwind response, we examined the responses of L. hesperus that were simultaneously exposed to a control artificial diet and a diet containing 12% KCl in a Y-tube olfactometer bioassay. Of the 95 adults tested, 47 selected the arm containing the normal diet and 48 selected the arm containing KCl-treated diet, indicating that dietary constituents did not preferentially attract or repel L. hesperus. The results from these studies strongly suggest that KCl negatively affects L. hesperus feeding behavior by functioning as a strong gustatory deterrent when concentrations exceed 0.5%. Visual and volatile cues appeared to have no role in mediating orientation or feeding behavior under these test conditions. [ABSTRACT FROM AUTHOR]

Abstract: The recent invasion of southern California by the glassy-winged sharpshooter (GWSS), Homalodisca coagulata (Say) (Hemiptera: Cicadellidae), has triggered a statewide control effort. Management of GWSS will include biological control using resident and imported natural enemies. Currently, very little information is available on the role of generalist predators in suppression of GWSS eggs, nymphs or adults. We have developed a sharpshooter egg-specific monoclonal antibody (MAb) for use as a diagnostic tool for predator gut content analysis. The MAb was tested by an indirect enzyme-linked immunosorbent assay (ELISA) for specificity to the different life stages of GWSS, smoke-tree sharpshooter (STSS), Homalodisca liturata Ball (Hemiptera: Cicadellidae), and various life stages of 27 other arthropod species. We found that the MAb only reacted to the egg stage of both sharpshooters and, to a lesser extent, to the adult stage of gravid GWSS and STSS females. Moreover, the ELISA was more responsive to younger GWSS eggs than older ones. Laboratory trials were conducted to determine how long GWSS egg antigen remained detectable in the guts of the green lacewing, Chrysoperla carnea Stephens (Neuroptera: Chrysopidae) and the ladybird beetle, Harmonia axyridis (Pallas) (Coleoptera: Coccinellidae) using both an indirect and sandwich ELISA format. We found that GWSS egg antigen was detectable for up to 30 and 12h in the guts of C. carnea and H. axyridis; respectively, and that the sandwich ELISA was much more sensitive than the indirect ELISA. Finally, 98 field-collected lacewings were examined for sharpshooter remains using our sharpshooter-specific sandwich ELISA. The assay detected sharpshooter egg antigen in 8.2% of the lacewings examined. This work represents a first step towards identifying the GWSS predator complex. [Copyright &y& Elsevier]

A 2-year commercial-scale study was conducted to qualitatively evaluate the effect of different insecticide treatment regimes on the predator complex attacking Bemisia tabaci (Gennadius) in cotton. In 1996 three insecticide regimes were compared: a rotation of conventional broad-spectrum insecticides or one of two different regimes based on the initial use of the insect growth regulators (IGRs), buprofezin and pyriproxyfen. In 1997 the same three regimes plus an untreated control were compared; split-plots were sprayed once for Lygus hesperus Knight control using a broad-spectrum insecticide. Relative feeding activity for each predator species was compared between treatment regimes by analyzing the gut contents of predators for the presence of whitefly remains using a whitefly-specific enzyme-linked immunosorbent assay (ELISA). The ELISA results were combined with predator density data to obtain a qualitative pesticide impact index for each predator group. In total, we analyzed the gut contents of 32?262 field-collected predators, representing nine different taxa. Of these, Pseudatomocelis seriatus (Reuter), Spanagonicus albofasciatus (Reuter), and spiders consisting primarily of Misumenops celer (Hentz) are shown to be whitefly predators for the first time. Predator populations were usually reduced in plots that received applications of broad-spectrum insecticides for B. tabaci and L. hesperus control, but there were few treatment differences in the proportions of predators containing whitefly remains in their guts. However, the feeding activity of certain predator species in fields sprayed with broad spectrum insecticides was significantly reduced compared with those in IGR-based and control treatments. Overall, insecticide regimes using IGRs were less lethal to the whitefly predator complex than regimes consisting of only conventional, broad-spectrum insecticides, but differences in predator feeding activity on whitefly between the various insecticide treatment regimes were minimal. [ABSTRACT FROM AUTHOR]

A series of tests were conducted to determine if the sensitivity and efficiency of an established rabbit immunoglobulin (IgG)-specific enzyme-linked immunosorbent assay (ELISA) could be improved for detecting a protein mark on insects. Five variations of ELISA were examined for their ability to detect a rabbit IgG mark on the convergent lady beetle, Hippodamia convergens Guérin-Méneville. The conventional sandwich ELISA was the most sensitive immunoassay based on the strength of the ELISA reaction and the proportion of individuals scoring positive for rabbit IgG. ELISAs were also conducted on rabbit IgG-marked beetles that were either homogenized or soaked in sample buffer prior to the assay. Results showed that homogenized beetles yielded higher ELISA values in the conventional ELISA than soaked beetles, but the qualitative response (i.e., percentage scoring positive for the mark) was about the same for up to 18 days after marking. Therefore, in some instances, simply soaking an individual beetle might be a viable alternative to the labour-intensive homogenization of the sample. Sandwich ELISAs with immunoreagent incubation intervals held constant at 5, 10, 20, or 60 min were also examined for their ability to detect rabbit-IgG-marked beetles. Results showed that the ELISA with immunoreagent incubations of 60 min yielded a significantly higher ELISA reading than the shorter intervals. However, all the marked beetles examined scored positive for the presence of rabbit IgG, regardless of the incubation interval. Finally, a test was conducted to determine if the conventional ELISA could also detect the presence of relatively inexpensive normal rabbit serum on marked beetles. Beetles marked with rabbit serum diluted one part rabbit serum to one, four, or eight parts water yielded statistically similar ELISA values to those beetles marked with the conventional rabbit IgG mark. [ABSTRACT FROM AUTHOR]

We combined two protein-marking enzyme-linked immunosorbent assays (ELISA) with a predator gut content ELISA to monitor the movement and feeding activity of commercially-purchased Hippodamia convergens Guèrin-Mèneville (Coleoptera: Coccinellidae) under realistic field conditions during two field seasons in central Arizona. The protein-marking ELISAs were used to differentiate released H. convergens from the native beetles. Commercially purchased beetles marked with rabbit immunoglobulin G (IgG) were released into cotton fields and chicken IgG marked beetles were released into adjacent cantaloupe fields. Results showed that the total native beetle abundance in each crop was about the same size. The recovery rates after 15 days for the released beetles were less than 1.0% over all the releases, indicating that they dispersed readily from the release site. Of the recaptured beetles containing rabbit IgG (cotton), 82.2% were recovered in cotton and 11.8% moved to cantaloupe. Of those containing chicken IgG (cantaloupe), 66.5% were recovered in cantaloupe and 33.5% moved to cotton. A predator gut content ELISA was used to determine if there were differences in the frequency of predation of released versus indigenous H. convergens on the silverleaf whitefly, Bemisia argentifolii Bellows & Perring (Homoptera: Aleyrodidae). The proportion of beetles containing whitefly antigens was always higher for the released beetles than for their native counterparts. Our results demonstrate an approach to combine protein marking and predator gut content ELISAs that allows the simultaneous comparison of feeding and intercrop movement of native and commercially-obtained biological control agents. [ABSTRACT FROM AUTHOR]

A large-scale study was conducted in 1996 to evaluate and demonstrate strategies for pest management of Bemisia tabaci (Gennadius) in cotton involving different insecticide regimes, application methods, and action thresholds. Here we examined the effects of the various management systems on the abundance and activity of native natural enemies. Population densities of 18 out of 20 taxa of arthropod predators were significantly higher in regimes initiated with the insect growth regulators (IGRs) buprofezin (chitin inhibitor) or pyriproxyfen (juvenile hormone analog) compared with a regime dependent on a rotation of conventional, broad-spectrum insecticides. There were no differences in predator density between the two IGR regimes, and generally no effects due to application method or action threshold level. Predator to prey ratios were significantly higher in regimes utilizing the two IGRs compared with the conventional regime, but were unaffected by application method or threshold level. Rates of parasitism by Eretmocerus eremicus Rose and Zolnerowich and Encarsia meritoria Gahan were higher in the IGR regimes compared with the conventional regime, but were unaffected by insecticide application method, or the action threshold used to initiate applications of the IGRs. Results demonstrate the selective action of these two IGRs and suggest that their use may enhance opportunities for conservation biological control in cotton systems affected by B. tabaci , especially relative to conventional insecticide alternatives. [ABSTRACT FROM AUTHOR]

We present a detailed description of how to build a lightweight, battery-operated suction trap to selectively collect minute insects. A single researcher can collect the contents from dozens of these traps in a matter of minutes. The trap is inexpensive, user-friendly, portable and non-lethal and non-destructive to trapped insects. [ABSTRACT FROM AUTHOR]

In this study, we validate and apply techniques for marking and capturing small parasitoids of the silverleaf whitefly, Bemisia argentifolii Bellows & Perring [ = B. tabaci (Gennadius), strain B] for mark-release-recapture (MRR) studies. The marker is the purified protein, rabbit immunoglobulin G (IgG), which was applied externally by topical spray or internally by feeding. Marked parasitoids were then assayed using a sandwich enzyme-linked immunosorbent assay (ELISA) for the presence of the protein marker using an antibody specific to rabbit IgG. Virtually all of the externally marked Eretmocerus sp. (Ethiopia, M96076) (98.0%) contained enough rabbit IgG to be easily distinguished from unmarked parasitoids, regardless of the amount of protein applied or the post-marking interval. A field MRR study was then conducted to examine the dispersal characteristics of E. emiratus Zolnerowich & Rose. Parasitoids marked externally and internally with protein were released on three separate trial dates into the center of a cotton field bordered by cantaloupe and okra. Overall, a total of 1388, 637, and 397 marked and unmarked wasps were captured in suction traps during each trial, respectively with the majority of parasitoids captured between 0600 and 0800 h. Furthermore, even though we released an equal proportion of males to females, our traps consistently contained more males. Our results suggest that there are gender-specific differences in the dispersal behavior of E. emiratus. Almost 40% of the captured parasitoids collected during the three release trials were positively identified for the presence of the protein marker. The distribution of the marked parasitoids revealed two distinct patterns. First, almost all of the marked parasitoids recaptured in the cotton plot were in suction traps at or adjacent to the. [ABSTRACT FROM AUTHOR]

Reviews the state of knowledge regarding insect marking. Characteristics of effective markers; Advantages of the techniques used in insect marking; Advances made in marking insects.

A follow-up study was conducted to further evaluate the marking efficiency of broadcast spray applications of egg albumin (from chicken egg whites) on Hippodamia convergens Guérin-Méneville (Coleoptera: Coccinellidae) in alfalfa. A previous study recorded exceptional marking efficiency (e.g., >95% of the population) on H. convergens when using relatively high concentrations (10 to 50%) of chicken egg whites. The present study examines marking efficiency of egg whites using lower concentrations of 2.5, 5.0, and 10.0%. We used cadaver and free-roaming beetles to measure protein mark acquisition (and retention) of each protein concentration by direct contact with the spray application and incidental contact with protein residue on the plant tissue, respectively. The vertical distribution of the protein mark was also determined by sampling the upper and lower portions of the alfalfa canopy. The data indicate, regardless of the egg white treatment, that the backpack sprayer provided uniform coverage of egg albumin on the alfalfa plants and cadaver beetles. Also, almost every free-roaming beetle acquired a mark within 24 h after contact exposure to protein marked plants. This study shows that a very low concentration of egg albumin is sufficient for marking arthropods directly in the field. [ABSTRACT FROM AUTHOR]

Acquisition and retention of two protein markers were tested on little fire ants, Wasmannia auropunctata Roger. Pure (100%) cow's milk and a dilution (10%) of chicken egg whites were applied to W. auropunctata directly by contact spray plus residue or indirectly via residual contact only with protein-marked plant debris. Protein-marked ants were held in plastic shoe-box-sized containers, collected at 0, 24, and 48 h after exposure to their respective marks, and then examined for the presence of the marks by a chicken egg albumin and milk casein-specific enzyme-linked immunosorbent assay. Cross-contamination rates were assessed by allowing ants marked with egg whites to interact with an equal number marked milk for 24 and 48 h, and then collected either individually or in bulk. Results indicated that the egg white biomarker was retained longer than milk and that more ants were successfully marked when the direct spray application method was employed. Cross-contamination rates were highest among bulk-collected ants and lowest among ants collected individually after 24 h. However, the rates of cross-contamination among individually collected ants increased and were similar to that of bulk-collected ants after 48 h. On the basis of our results, external protein marking may not be suitable if mass trapping is required or if the study extends beyond 24 h due to high cross-contamination rates among specimens collected in bulk and reduced marker detection rates. [ABSTRACT FROM AUTHOR]

A universal food immunomarking technique (UFIT) is described for postmortem gut analysis detection of predation on the egg stage of Lygus hesperus Knight (Hemiptera: Miridae). Collops vittatus Say (Coleoptera: Melyridae) and Hippodamia convergens Guérin-Méneville (Coleoptera: Coccinellidae) were fed a single L. hesperus egg that was marked with rabbit and chicken sera proteins. The protein-marked egg remnants were detectable in the guts of the majority of the predators by each sera-specific enzyme-linked immunosorbent assay (ELISA) for 3 to 6 h after a feeding event. A novel technique was then developed to expose protein-marked eggs to predators that simulated the L. hesperus endophytic oviposition behavior. The procedure entailed embedding L. hesperus eggs in an artificial substrate that mimicked the stem of a plant. A predator feeding choice study was then conducted in cages that contained a cotton plant and artificial stems containing endophytic (concealed) and exophytic (exposed) egg patches. The endophytic and exophytic egg treatments were marked with chicken and rabbit protein, respectively. The gut analyses revealed that higher proportions of both predator populations contained remnants of the exophytic egg treatment and L. hesperus eggs were more vulnerable to C. vittatus than H. convergens. This study shows how the UFIT can be used to pinpoint stage-specific feeding activity on two distinct egg exposure treatments (endophytic and exophytic) of the same species. [ABSTRACT FROM AUTHOR]

Alfalfa (Medicago sativa L.) (Fabales: Fabaceae) can be strategically planted as a trap crop for Lygus spp. in California’s organic strawberry fields. Alfalfa has been shown to attract both Lygus spp. and, in turn, a Lygus -specific parasitoid, Peristenus relictus (Ruthe) (Hymenoptera: Braconidae). However, the impact of alfalfa trap-cropped strawberries on the Lygus spp. predator complex is unknown. Here we identify key predators of Lygus spp. found in organic strawberry. First, a general survey was conducted at an organic, non-trap cropped strawberry farm, to quantify predator abundance and to qualitatively assess their feeding activity on Lygus spp. We identified the 11 most abundant predator taxa present and, by using a Lygus -specific PCR assay, determined that about 18% of the insects and spiders contained Lygus spp. remains in their guts. We then conducted a study to examine alfalfa’s role in conserving the most relevant predators in trap-cropped organic strawberries. Specifically, we quantified predator abundance and qualitatively measured predator feeding activity (by gut analysis) on Lygus spp. collected in strawberry plots either lacking or containing an alfalfa trap crop. Data revealed that some predator taxa, including the numerically dominant predator, Orius tristicolor (White) (Hemiptera: Anthocoridae), aggregated in alfalfa trap crops. The gut content analyses revealed that insect and spider predators collected from the alfalfa trap crop had a significantly higher proportion of their population containing Lygus spp. remains than those collected from nearby rows of strawberries. These results suggest that alfalfa trap cropping might be a useful tactic for conserving the biological control services of generalist predators in organically grown strawberries in California. [ABSTRACT FROM AUTHOR]

Flight mills are widely used to investigate insect flight behavior. As technology advances, the means to build a computerized control system for a flight mill has become more accessible in terms of both price and availability of components. However, the specialized electronics and programming knowledge required to build such a system can still present an obstacle to interested parties. Here, we describe a simple and inexpensive flight mill control system that can be easily assembled and operated without specialized experience. The hardware and software components are built around an Arduino single-board microcontroller, which outputs raw data in the form of timestamped detections of rotations of the flight mill arm. This control system is suitable both as the basis for new flight mills and for replacing outdated computer controls on existing flight mills. Additionally, it can be used with any rotary flight mill design that uses an electronic sensor to count rotations. [ABSTRACT FROM AUTHOR]

The managed, solitary bee, Osmia lignaria Say, is an efficient pollinator of orchard crops. One limitation to their commercial success is high dispersal of populations away from orchards, resulting in low establishment in provided nest cavities even when optimal pollination is achieved. While exact causes for dispersal are unknown, many existing theories remain untested due to complications with evaluating O. lignaria establishment in field settings. We describe relatively simple and reliable methods for passively marking O. lignaria with egg albumin and casein powdered proteins combined with orange fluorescent powder as they emerge from cocoons. Marked adults were examined microscopically at 0, 3, 6, 9, 12, 15, and 18 days after emergence for the fluorescent powder followed by an anti-albumin and anti-casein enzyme-linked immunosorbent assay to detect the protein powders. The orange powder and egg albumin were highly persistent on adults throughout the 18-day study, suggesting the utility of these markers for studying dispersal and retention of O. lignaria in the field. [ABSTRACT FROM AUTHOR]

Drosophila suzukii Matsumura ( Diptera: Drosophilidae) utilizes ' Himalaya' blackberry, Rubus armeniacus Focke ( Rosaceae), as a host and may invade berry and stone fruit crops from field margins containing this invasive weed. Laboratory and semi-field studies were conducted to determine (1) the persistence of protein marks including 10% chicken egg whites (egg albumin protein), 20% bovine milk (milk casein protein), and 20% soy milk (soy trypsin inhibitor protein) on topically sprayed D. suzukii, (2) protein retention on blackberry leaves, and (3) D. suzukii acquisition of protein after exposure to marked blackberry leaves for up to 14 days after application. All flies and leaves were assayed for the presence of the protein marks using protein-specific enzyme-linked immunosorbent assays. Egg albumin, milk casein, and soy trypsin proteins persisted on 94, 49, and 25% of the topically marked D. suzukii, respectively, throughout the 14-day study period. Egg albumin was retained on 100% of treated leaves for 14 days, regardless of environmental conditions. At least 50% of flies exposed residually to egg albumin-treated leaves were marked for 3 days, regardless of exposure time and environmental conditions. However, increasing fly exposure time to treated leaves in April and June appeared to improve protein mark acquisition. Acquisition of protein by flies from treated leaves for milk casein was inconsistent, and poor for soy trypsin, despite detectable levels on treated leaves. Egg albumin had the longest and most consistent persistence on flies, leaves, and flies exposed to leaves in laboratory and semi-field studies, under a variety of environmental conditions and exposure times. [ABSTRACT FROM AUTHOR]

Abstract: In predator–prey interactions, a widely held view is that prey species have higher dispersal rates relative to their predators and are thereby able to escape from predation by colonizing habitats before their predators. Despite major implications for predator–prey interactions, community assembly, and biological control, this view has rarely been tested, and measuring relative dispersal abilities is often complicated by colonizing predators and prey originating from different locations. In California’s San Joaquin Valley, the periodic harvest of alfalfa presents an opportunity to measure dispersal of a key generalist pest, Lygus spp., relative to a suite of its generalist predators. We performed a large-scale mark-capture study by marking a mature alfalfa field containing Lygus and its predators with an aerial application of a protein marker. The alfalfa was then harvested by the grower, prompting a dispersal event. At several times following harvest, surrounding cotton fields were sampled at known distances from the marked field to quantify movement by Lygus and its predators. Contrary to the general view, our data do not suggest that Lygus routinely out-disperses its suite of predators. Instead, the mean dispersal distance for Lygus fell near the average dispersal distances of its predators. Implications for biological control are discussed in light of these results, and the importance of predators’ trophic strategy is stressed. [Copyright &y& Elsevier]

A greenhouse study was conducted that compared the protein mark retention time of a well-established rabbit IgG protein detection protocol with those of three newer, less expensive protein detection protocols designed to detect casein in bovine milk, egg albumin in chicken egg whites, and soy trypsin in soy milk, respectively. Adult convergent lady beetles, Hippodamia convergens Guérin-Méneville (Coleoptera: Coccinellidae), were topically marked with either 2.0 ml of a 5.0 mg ml−1 rabbit IgG solution or 2.0 ml of pure bovine milk, chicken egg whites, or soy milk solutions. The variously marked cohorts of beetles were then released into cages that contained a single cotton plant. In turn, beetles were collected every other day for 26 days after marking and assayed for the presence of the protein marks by either a sandwich anti-rabbit IgG enzyme-linked immunosorbent assay ( ELISA) or an indirect anti-casein, anti-egg albumin, or anti-soy trypsin ELISA to detect bovine casein, chicken egg albumin, or soy milk trypsin, respectively. Data indicate that the durability of the protein markers on the beetles decreases in the following order: egg whites > rabbit IgG > milk > soy milk. In addition, the mortality of H. convergens after receiving each protein mark treatment was assessed. Data revealed that there were no significant differences in mean mortality of beetles between any of the protein treatments. Overall mortality during the course of the 26-day study ranged from 30% for the soy-marked beetles to 50% for the water and rabbit IgG-marked beetles. [ABSTRACT FROM AUTHOR]

To aid in identifying key predators of Proconiini sharpshooter species present in California, we developed and tested molecular diagnostic markers for the glassy-winged sharpshooter, Homalodisca coagulata (Say), and smoke-tree sharpshooter, Homalodisca liturata (Ball) (Homoptera: Cicadellidae). Two different types of markers were compared, those targeting single-copy sequence characterized amplified regions (SCAR) and mitochondrial markers targeting the multicopy cytochrome oxidase subunit genes I (COI) and II (COII). A total of six markers were developed, two SCAR and four mitochondrial COI or COII markers. Specificity assays demonstrated that SCAR marker HcF5/HcR7 was H. coagulata specific and HcF6/HcR9 was H. coagulata/ H. liturata specific. COI (HcCOI-F/R) and COII (HcCOII-F4/R4) markers were H. coagulata specific, COII (G/S-COII-F/R) marker was H. coagulata/ H. liturata specific, and lastly, COII marker (Hl-COII-F/R) was H. liturata specific. Sensitivity assays using genomic DNA showed the COI marker to be the most sensitive marker with a detection limit of 6 pg of DNA. This marker was 66-fold more sensitive than marker Hl-COII-F/R that showed a detection limit of 400 pg of DNA. In addition, the COI marker was 4.2-fold more sensitive than the COII marker. In predator gut assays, the COI and COII markers demonstrated significantly higher detection efficiency than the SCAR markers. Furthermore, the COI marker demonstrated slightly higher detection efficiency over the COII marker. Lastly, we describe the inclusion of an internal control (28S amplification) for predation studies performing predator gut analyses utilizing the polymerase chain reaction (PCR). This control was critical in order to monitor reactions for PCR failures, PCR inhibitors, and for the presence of DNA. [ABSTRACT FROM AUTHOR]

Field studies were conducted from 1997 to 1999 to contrast the effects of two insect growth regulators (IGRs) and conventional insecticides on natural enemy conservation in cotton within the context of alternative management strategies for Bemisia tabaci (Gennadius). Compared with an untreated control, insecticide regimes based on the initial use of the IGR buprofezin or pyriproxyfen reduced densities of eight predator taxa out of 20 examined in at least one year, including common species such as Geocoris punctipes (Say), Nabis alternatus Parshley, Chrysoperla carnea s.l., and the empidid fly Drapetis nr. divergens. Patterns of predator and pest population change relative to IGR application dates suggest that factors other than direct toxic effects, such as reduction in prey availability, were likely involved. In comparison, the use of conventional insecticides reduced populations of nearly all the predatory taxa examined in most years, including those affected by IGRs, with the impact being greater and more immediate in all cases. Predator:prey ratios were significantly increased by the use of IGRs compared with both the untreated control and a conventional insecticide regime in most instances. The application of conventional insecticides for suppression of Lygus hesperus Knight, another key pest in the system, in a split-plot design reduced densities of most predator taxa and diminished the selective advantage of the IGRs. Rates of parasitism by aphelinid parasitoids (Eretmocerus eremicus Rose and Zolnerowich and Encarsia spp.) were generally low and did not vary consistently due to B. tabaci or L. hesperus insecticide regimes over the three years. Our 3-year study demonstrates the more selective action of buprofezin and pyriproxyfen in an effective integrated control system for B. tabaci. The use of these IGRs could further facilitate biologically based management in cotton production systems. [Copyright &y& Elsevier]

Understanding the dispersal ability of invasive insects provides useful insights for developing effective management strategies. Historically, methods for marking insects for dispersal studies have been expensive, time‐consuming, labor‐intensive, and oftentimes ineffective, especially for woodboring beetles. Also, capturing or rearing insects requires human handling, which can alter behavior. Protein immunomarking is a well‐established technique for studying the dispersal of insects; however, it has not been applied to woodborers. This study evaluates the potential for using protein immunomarkers applied directly to woodborer‐infested trees to mark emerging beetles. Specifically, in the first experiment, we sprayed varying concentrations of ovalbumin (egg white) solution directly onto logs infested with emerald ash borer (EAB), Agrilus planipennis Fairmaire (Coleoptera: Buprestidae, Agrilini). In turn, an enzyme‐linked immunosorbent assay was used to detect the presence of protein on emerged beetles. To test the persistence of the mark, we applied varying concentrations of albumin to freeze‐killed beetles, mounted them on pins, and placed them over various time intervals in an exposed location outdoors. Adult EAB self‐marked as they emerged from protein‐treated trees, with higher protein concentrations persisting for longer on the cuticle. This technique offers a convenient, inexpensive, and durable means of marking woodborers and circumvents the need for human handling, allowing for more natural behavior and more realistic estimates of dispersal. Protein self‐marking may find application in studies of woodborer dispersal within natural forest environments. [ABSTRACT FROM AUTHOR]

Studies of bee movement and activities across a landscape are important for developing an understanding of their behavior and their ability to withstand environmental stress. Recent research has shown that proteins, such as egg albumin, are effective for mass-marking bees. However, current protein mass-marking techniques require sacrificing individual bees during the data collection process. A nonlethal sampling method for protein mark-capture research is sorely needed, particularly for vulnerable, sensitive, or economically valuable species. This study describes a nonlethal sampling method, in which three non-Apis bee species (Bombus bifarius Cresson [Hymenoptera: Apidae], Osmia lignaria Say [Hymenoptera: Megachilidae], and Megachile rotundata Fabricius [Hymenoptera: Megachilidae]) were tested for a unique protein marker by immersing them momentarily in saline buffer and releasing them. Results showed that an egg albumin-specific enzyme-linked immunosorbent assay was 100% effective at detecting the protein on bees that were sampled nonlethally. Furthermore, this sampling method did not have an impact on bee survivorship, suggesting that immersing bees in buffer is a reliable and valid surrogate to traditional, destructive sampling methods for mark-capture bee studies. [ABSTRACT FROM AUTHOR]

The adult dustywing, Semidalis flinti Meinander (Neuroptera: Coniopterygidae), begins producing circular-shaped waxy particles after eclosion. The waxy material, which forms the particles, is extruded from individual pores found in clusters on the abdomen. Pores also are present in two rows of three pores on the frontalis and two pores on the first segment of each antennae. The pores have a rosette-like appearance and each pore extrudes dual waxy ribbons. As each ribbon extends a short distance out of the pore, it begins to curl back on itself until the end makes contact with the ribbon. The curled end then breaks free from the extruding ribbon to form the circular waxy particles with fluted edges approximately 2.75-μm diameter. The adults use the particles to cover all parts of their body except for their eyes and appear to lightly coat their antennae. The lipid portion of the particles consists largely of free fatty acids, almost exclusively the 24-carbon fatty acid, tetracosanoic acid. Minor lipid classes are hydrocarbons, fatty alcohols and unidentified material. [Copyright &y& Elsevier]