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Stink bugs (Hemiptera: Pentatomidae) are ubiquitous, cryptic, phytophagous pests that are found in many crops. In agroecosystems, individuals disperse from adjacent noncrop hosts and tend to aggregate or cluster within fields. In this study, we characterized the distribution of Euschistus servus (Say) and Euschistus tristigmus (Say) (Hemiptera: Pentatomidae) over 2 yr at three southeastern United States farmscapes. Stink bugs were captured in pheromone-baited traps, and Spatial Analysis by Distance Indices (SADIE) used to identify the location of significant aggregations by habitat type and season. Euschistus servus adults were more likely to be captured in pecan orchards, cotton, other crops, or unmanaged habitats than in woodland habitats. Significant aggregations of E. servus were detected in a variety of habitats including pecan, corn, cotton, peanut, and tobacco, as well as fallow and hay fields, pastures, and hedgerows. Fewer adult E. tristigmus were captured than E. servus adults, and E. tristigmus adults were typically trapped and aggregated in woodland habitats. The resulting data provide an important understanding regarding the seasonal movement and relative abundance levels of stink bug populations, which are critical to the development of integrated pest management strategies.

The pupal soil cell of the pecan weevil, Curculio caryae (Coleoptera: Curculionidae), was reported previously to exhibit antibiosis to an entomopathogenic fungus, Beauveria bassiana. The objectives of this study were to examine 1) if the antimicrobial effect occurs in other insects that form pupal cells, 2) whether the effect extends to plant pathogenic fungi, and 3) identify the source of antibiosis in pupal soil cells of C. caryae. Antibiosis of pupal cells against B. bassiana was confirmed in-vitro in three additional curculionids, Diaprepes abbreviatus, Conotrachelus nenuphar, and Pissodes nemorensis, all of which had fewer fungal colonies relative to controls. Pupal soil cells were found to suppress phytopathogenic fungi in-vitro, including suppression of Alternaria solani by D. abbreviatus pupal cell, and that of Monilinia fructicola by C. caryae. The detection of antibiosis of soil cells formed by surface-sterilized insects using sterile soil implies the antimicrobial effect stemmed from inside the insect. Further, a novel biotic mechanism was identified: a bacterium related to Serratia nematodiphila was isolated from C. caryae pupal soil cells and was found to be associated with antibiosis. The bacterial cultures with or without autoclave had similar effects but were not as potent as pupal soil cells for suppressing B. bassiana. Also, autoclaved soil cells and autoclaved bacterial culture suppressed M. fructicola but were not as inhibitory as non-autoclaved soil cells. This indicates that antibiosis may be due to bacterial metabolites, although other factors may also be involved. Our findings suggest potential to develop the antibiotic compounds as novel bio-fungicides to control plant diseases.

Stink bugs (Pentatomidae) and leaffooted bugs (Coreidae) are important direct pests of many seed, fruit, vegetable and nut crops. Recently they have become serious pests of cotton because of the reduction in pesticide use resulting from the eradication of the boll weevil and the implementation of genetically-modified cotton. This document is ENY-718, one of a series of Entomology and Nematology Department, Florida Cooperative Extension Services, Institute of Food and Agricultural Sciences, University of Florida. Publication Date: April 2005. ENY-718/IN534: Stink Bugs and Leaffooted Bugs Are Important Fruit, Nut, Seed and Vegetable Pests (ufl.edu)

Sharpshooter is a term commonly used to describe a group of leafhoppers in the family Cicadellidae. There have been several explanations for the use of this term. Riley and Howard (1893) first used 'sharpshooter' to describe the feeding damage of the glassy-winged sharpshooter, Homalodisca coagulata (Say), on cotton. This damage was caused by the piercing-sucking mouthparts of H. coagulata that appeared to be caused by a 'minute bullet.' They also reported 'rapid and forcible ejection of minute drops of fluid' as another explanation for the use of this term. The term sharpshooter is also attributed to the hiding behavior of these insects when alarmed. Disturbed sharpshooters will slip quickly behind branches and stems to avoid predators, an action not unlike the behavior of army sharpshooter riflemen who would hide behind the trunks of trees to avoid detection by the opposition as they passed by their position. This document is EENY-334 , one of a series of Featured Creatures from the Entomology and Nematology Department, Florida Cooperative Extension Service, Institute of Food and Agricultural Sciences, University of Florida. Published: October 2004. EENY-334/IN611: Sharpshooters, Leafhoppers, Cicadellidae (Insecta: Hemiptera: Auchenorrhyncha: Cicadellidae) (ufl.edu)

The efficacy of aboveground applications of entomopathogenic nematodes (Heterorhabditis spp. and Steinernema spp.) can be severely limited by the nematode’s susceptibility to UV radiation and desiccation. The lesser peachtree borer, Synanthedon pictipes, is a major pest of stone fruit; larvae attack trees aboveground by tunneling into the trunk and scaffold limbs. In previous research, Steinernema carpocapsae, caused high levels of S. pictipes mortality when a sprayable fire gel (Barricade®) was applied on top of the nematode application as a protectant. One drawback to the approach is that two applications must be made (first nematodes are applied followed by the fire gel); furthermore, the previous experiments did not compare nematode application to the existing standard chemical insecticide. Therefore, the objectives of this study were to (1) determine if a diluted rate of fire gel can protect nematodes when applied as a single spray, and (2) compare the efficacy of nematode applications with the chemical insecticide, chlorpyrifos. The experiment was conducted in a peach orchard in Quincy, Florida in 2013 and 2014. Treatments included: (1) chlorpyrifos, (2) S. carpocapsae applied in aqueous suspension only or (3) with a full rate (approximately 4% applied separately) or (4) 2% Barricade® (applied with nematodes in a single spray), and (5) a non-treated control. The treatments were applied post-harvest (in the fall) to S. pictipes-infested bark wounds; S. pictipes survival was assessed 8 (2013) or 14 (2014) d post-application. In 2013, chlorpyrifos and nematodes with Barricade® at 2% or the full rate reduced S. pictipes survival relative to the non-treated control and nematodes without Barricade®. In 2014, nematodes applied with 2% Barricade® was the only treatment that reduced S. pictipes survival. We conclude that S. carpocapsae and Barricade® can be applied as a single spray, and in our experiments the treatment was at least as effective as the chemical standard.

Crape myrtle, Lagerstroemia species (Myrtales: Lythraceae), has become a dominant flowering plant in the ecosystems of the southeastern USA. Examination of flower records for bees shows few records of pollinators visiting these species even though they produce dimorphic pollen. Sampling of bees from a multi-cultivar crape myrtle planting at the University of Florida's Institute of Food and Agricultural Sciences, North Florida Research & Education Center in Quincy, Florida, via established transect walks in 2009 and 2010, and intensive net collecting in 2011, indicated that bee species from several functional groups (based on taxonomy, body size, and sociality) visited crape myrtle. Results also indicated that crape myrtle cultivars were used differently by the following major bee species (Hymenoptera: Apidae): the honey bee, Apis mellifera L.; the bumble bees Bombus impatiens Cresson and Bombus fraternus (Smith); and the carpenter bees Xylocopa micans Lepeletier and Xylocopa virginica (L.). Numbe...

Summary Apparently because of mulch buildup and abstinence from pesticide use, an organically managed citrus grove in Vero Beach, Florida, can support large populations of long-legged flies (Diptera: Dolichopodidae) that impose predation pressure on inundative releases of Tamarixia radiata (Waterston) (Hymenoptera: Eulophidae) parasitoid wasps to control the Asian citrus psyllid (Hemiptera: Liviidae). During peak activity, flies on wing characteristically hawk wasps in mid-air as the wasps are sprinkled from shipment containers onto the leaves of citrus plants. Flies on leaves enter into entrained scramble competition for prey by systematically “canvassing” upper leaf surfaces in rapid, jerked movements and, albeit infrequently, attack and eat wasps when encountered during this behavior.

Plantings of perennial grasses have been shown to be an effective means to enhance soil qualities for organic production. Similarly, tillage methods can significantly impact production in organic crop production systems. We have previously examined direct effects of these practices on crop yields, profitability, and soil quality for rotations of organic vegetables in a 4-yr study in northern Florida, but less is known about the effects of these treatments on arthropods. We report here on experiments that used large fields of Argentine bahiagrass, Paspalum notatum Flugge (Poaceae) ‘Tifton 9,’ converted to seasonal vegetable rotations of oat/rye, bush beans, soybeans, and broccoli in a nested design using 4 levels (yr) of continuous bahiagrass production prior to vegetable rotations and 2 tillage methods (conventional and strip tillage). During the fourth yr of the study, we conducted pitfall trapping on a subset of plots involving all 8 treatments (4 bahiagrass treatments and 2 tillage treatments) to examine effects on epigeal arthropods. Over 10,000 organisms and 48 species were identified with 36 arthropod species comprising greater than 97% of the collected specimens. Fields with increasing yr in bahiagrass significantly increased the number of carabid beetles, whereas there was a decline in total herbivores. Tillage treatments impacted arthropod abundance with a noted decline in total carabids collected in strip tilled plots. Pest management implications of these treatments are discussed.

The peachtree borer, Synanthedon exitiosa, is a major pest of stone fruit trees in North America. In prior studies, the entomopathogenic nematode, Steinernema carpocapsae, caused substantial reductions in S. exitiosa damage when applied by watering can to peach trees that were irrigated regularly. Here we report two additional studies that assessed S. carpocapsae efficacy in suppressing S. exitiosa damage in peach orchards; one study focused on irrigation requirements and the other on application method. In the first experiment we compared S. carpocapsae applied with and without irrigation, and application of a sprayable gel, Barricade , as a potential replacement for irrigation. In the second experiment, we compared application methods that growers might use including a boom sprayer, handgun, trunk sprayer and watering can (used as a positive control). In both experiments chlorpyrifos was also included as a positive control, and in the application methods experiment an untreated (negative) control was also included. All treatments were applied in the fall of 2012 and 2013 and S. exitiosa infestation was assessed following the spring of 2013 and 2014, respectively. In the first experiment, nematodes applied without irrigation did not prevent high levels of infestation levels (75% of trees were infested) whereas nematodes applied with the sprayable gel suppressed damage at the same level as chlorpyrifos (

The pecan weevil, Curculio caryae (Horn) (Coleoptera: Curculionidae), is a key pest of pecans Carya illinoinensis ([Wangenh.] K. Koch) (Fagales: Juglandaceae). Control recommendations rely on broad spectrum chemical insecticides. Due to regulatory and environmental concerns, effective alternatives for C. caryae control must be sought for pecan production in conventional and organic systems. We explored the use of microbial biopesticides for control of C. caryae in Georgia pecan orchards. Three experiments were conducted. The first investigated an integrated microbial control approach in an organic system at two locations. Three microbial agents, Grandevo (based on byproducts of the bacterium Chromobacterium subtsugae Martin, Gundersen-Rindal, Blackburn & Buyer), the entomopathogenic nematode Steinernema carpocapsae (Weiser), and entomopathogenic fungus Beauveria bassiana (Balsamo) Vuillemin, were applied to each treatment plot (0.6 ha) at different times during the season. A second experiment compared the effects of S. carpocapsae and B. bassiana applied as single treatments relative to application of both agents (at different times); survival of C. caryae was assessed approximately 11 mo after larvae were added to pots sunk in an organic pecan orchard. In a conventional orchard (with 1.0 ha plots), the third experiment compared Grandevo applications to a commonly used regime of chemical insecticides (carbaryl alternated with a pyrethroid). All experiments were repeated in consecutive years. The combined pest management tactic (experiment 1) reduced C. caryae infestation relative to non-treated control plots in both locations in 2014 and one of the two locations in 2015 (the other location had less than 1% infestation). In experiment 2, no differences among combined microbial treatments, single-applied microbial treatments or different numbers of application were observed, yet all microbial treatments reduced C. caryae survival relative to the control. In the third experiment, both Grandevo and standard chemical insecticide applications resulted in lower weevil infestation than the control (both years) and there was no difference between the insecticide treatments in 2014 although the chemical insecticide regime had slightly lower infestation in 2015. These results provide evidence that microbial biopesticides can substantially reduce pecan weevil infestations in organic and nonorganic systems.

USDA Animal Plant Health Inspection Service Plant Protection and Quarantine (APHIS-PPQ) and Customs and Border Protection (CBP) inspect traffic entering the United States for arthropods posing a threat to national agriculture or ecosystems. We analyzed interceptions made by these agencies in Puerto Rico and the U.S. Virgin Islands between October 2006 and December 2009 for patterns with regard to the frequency of interceptions, origins of interceptions, and the taxa intercepted. 6,952 arthropods were intercepted in freight or luggage entering Puerto Rico and the U.S. Virgin Islands from foreign countries and 9,840 arthropods were intercepted from freight or luggage leaving Puerto Rico or the U.S. Virgin Islands destined for mainland U.S. Most (77%) of the arthropods intercepted entering Puerto Rico were intercepted in freight or luggage originating within the Caribbean. Most intercepted arthropods were in the order Hemiptera (52% of all interceptions), followed by Diptera (16%), Coleoptera (10%), Lepidoptera (8%), Thysanoptera (5%), Acari (4%), and Hymenoptera (2%). Intercepted arthropods from foreign countries were more equitably spread among orders, whereas 89% of the arthropods intercepted from Puerto Rico and the U.S. Virgin Islands were in the orders Hemiptera and Diptera. Hemiptera made up 28% of the interceptions from foreign countries, but 69% of the interceptions made from Puerto Rico and the U.S. Virgin Islands. Only 7 of 28 adventive arthropods recently established in Puerto Rico were intercepted during this study, and these were intercepted at relatively low frequency (between 3 and 132 interceptions; mean of 35 interceptions). We present data suggesting that most adventive arthropods that occur in both Puerto Rico and Florida established in Florida first, likely due to less stringent or non-existent import inspections for traffic coming into Puerto Rico from the U.S. Finally, we highlight several adventive arthropods that have recently established in Puerto Rico and discuss what we can learn from these invaders.

Caribovia coffeacola, Cicadellinae, coffee, Xylella fastidiosa.

Stink bugs (Heteroptera: Pentatomidae), including Nezara viridula (L.), Euschistus servus (Say), and Chinavia hilaris (Say), are economic pests in farmscapes where they move within and between closely associated crop and non-crop habitats. Thus, field edges in these farmscapes include not only crop-to-crop interfaces but also those edges adjoining non-crop habitats. We examined the influence of field edges on colonization of stink bugs in southeastern USA farmscapes composed of typical combinations of corn, peanut, and cotton. For E. servus and N. viridula, egg-to-adult development and presence of both sexes on all crops indicated that the crops served as reproductive plants. Adult C. hilaris were rarely found on corn and on crops associated with it, and they were present mainly in cotton in peanut–cotton farmscapes. Mature crop height was significantly higher for corn than for cotton and significantly higher for cotton over peanut, and an edge effect in dispersal of stink bugs into a crop was detected up to 4.6, 8.2, and 14.6 m from the crop-to-crop interface in corn, cotton, and peanut, respectively. These results suggest that stink bug dispersal into a crop decreases as crop height increases. The first stink bug-infested crop at the crop-to-crop interface was the most significant contributor of colonizing stink bugs to an adjacent crop. An edge effect in dispersal of stink bug adults was detected in corn next to non-woodlands and woodlands and in cotton adjacent to woodlands. Edge effects were never detected in side edges of peanut. Overall, our results indicate that both plant height and host plant suitability can influence edge-mediated dispersal of stink bugs at field edges.

The nine-banded armadillo (Dasypus novemcinctus), invasive to Florida and Georgia, is thought to be an important predator of nesting vertebrate species in some areas; yet little is known about how armadillos find these nests and how often depredations occur in areas with low nest densities. To quantify the armadillo's attraction to nests of two species of conservation concern, northern bobwhite quail (Colinus virginianus) and gopher tortoise (Gopherus polyphemus), and to evaluate if armadillos are more attracted to cues from prior depredation than to cues from intact nests, we conducted experiments with both captive and wild armadillos. Our results indicate that armadillos did not use cues from prior depredations to find nests; nor did they exhibit a strong attraction to eggs overall. Our results suggest that armadillos are unlikely to alter the demographics of gopher tortoises or bobwhite quail within habitats of low nest density.

Ornamental flowers, shrubs and trees are economically important commodities in the US and around the globe. In this study we evaluated the potential of entomopathogenic nematodes to control two important ornamental pests: 1) Corythucha ciliata (Say) (Hemiptera: Tingidae), a native lace bug that attacks the foliage of sycamore trees, and 2) the recently described exotic pest, Stethobaris nemesis (Coleoptera: Curculionidae), a weevil that attacks amaryllis leaves and bulbs. In the laboratory, the virulence of six entomopathogenic nematode strains (comprising five species) was evaluated on sycamore leaf discs for potential to control C. ciliata, and four nematode species were evaluated for control of S. nemesis. Heterorhabditis indica (HOM1) exhibited higher virulence to C. ciliata than H. bacteriophora (Baine and Oswego strains), H. georgiana (Kesha), and Steinernema riobrave (355); S. carpocapsae (All) virulence was not statistically separated from the other nematodes with the exception of H. bact...

Organisms must find food and avoid enemies. Homalodisca vitripennis (Germar) is a primary vector of Xylella fastidiosa , the causal agent of Pierce's disease, a deadly disease of grapevines and other plants. H. vitripennis feeds on xylem tissue depauperate in nutrients and has evolved many specialized physiological and behavioral adaptations. Bottom-up mortality risks to H. vitripennis include starvation and reduced fecundity through loss of quality hosts. Top-down risks include predation, egg parasitism by Hymenoptera, and fungal pathogens. Visual behavior of H. vitripennis in response to congeners, common heterospecifics, and artificial models of conspecifics was investigated. Behaviors and the physical properties of the visual cues involved were characterized. H. vitripennis adults exhibited highly significant, positive responses to conspecifics, a heterospecific species, Oncometopia nigricans , and artificial models the size of adult leafhoppers. Significant response was not observed to a congeneric, Homalodisca insolita , with a smaller body size, or to models of sizes, shapes, and colors other than black and red. Cadavers of leafhoppers placed on a novel and nutritionally poor host plant stimulated H. vitripennis adults to land on branches containing the cadavers. H. vitripennis also landed preferentially on branches containing conspecific cadavers despite the presence of a cadaver of a major predator, Anolis carolinensis lizards, or artificial lures resembling spiders. This consistent visual response was independent of variable bottom-up (host quality) and top-down (predator presence) risks, and it suggests for the first time such parsimonious behavior in insects, i.e., sole use of a live visual cue as a means to reduce mortality risks from bottom-up and top-down forces.

The nine-banded armadillo (Dasypus novemcinctus) is considered by many to be one of the greatest nuisance wildlife species in the Southeastern United States. Management is difficult because no repellents, toxicants, or fumigants are currently registered for this species; exclusion is laborious because armadillos are adept burrowers; and no effective trapping attractants have been identified. If a suitable lure were discovered, trap capture success could increase and the frequency of nuisance complaints could decrease. We compared the behavioral attractiveness to captive armadillos of 15 commercially available food materials, as well as scents collected from conspecifics, in Florida, USA, 2008-2009. According to 3 distinct behavioral measures, 4 materials consistently elicited the most attraction responses from armadillos: pond worms (Lumbricus terrestris), crickets (Acheta domesticus), red worms (Eisenia fetida), and wigglers (Pheretima hawayanus). Recognizing that all of these materials were live prey, we devised a second series of experiments to evaluate the relative importance of olfactory cues versus auditory-vibrational cues in evoking a response from armadillos. Results suggested auditory-vibrational cues were meaningful. Finally, we measured sound pressure and vibration levels produced by the most preferred and less preferred prey items. Sound and vibrational cues decreased rapidly below background noise levels within 10-30 cm from baits. Because of this, and because the perceptual range of armadillos to the olfactory cues from these baits appears limited, traps baited with any worm or cricket are unlikely to lure armadillos from great distances. Development of an effective baiting system will require further investigation into the possibility of enhancing the ability of stimuli to travel over long distances. 2011 The Wildlife Society.

Insects in the order Hemiptera are considered the second most important group of plant pathogen vectors, after aphids as agriculture crop pests. Genomic approaches are providing new information on the genetic basis of biology, behavior, and refinement of their phylogenetic classification. Three leafhopper species, important as vectors of plant pathogenic bacteria referred to as Xylella fastidiosa (Hemiptera: Cicadellidae), were examined by comparison of the available expressed sequence tags, ∼43,400 ESTs from three leafhopper species (Hunter datasets, NCBI). These species are vectors of the plant-pathogenic bacterium, Xylella fastidiosa (Wells et al.) the causal agent of Pierce's disease of grapevine. A tentative look at the gene expression across these three leafhopper species, the glassy-winged sharpshooter, Homalodisca vitripennis (Germar), blue-green sharpshooter, Graphocephala atropunctata (Signoret), and black-winged sharpshooter, Oncometopia nigricans (Walker), were analyzed. After compar...

Six types of sticky card traps differing in color and trapping adhesive were evaluated for monitoring Asian citrus psyllid in citrus in the United States (Florida and Texas). We coded the six traps as ASYellow, GLYellow, RWYellow, ASACP, ASGreen and MGGreen. The ASYellow, GLYellow and RWYellow traps were a bright yellow color to the human eye but the yellow color of these traps varied in intensity. To the human eye, the ASACP traps were a lime-green color, the MGGreen trap was a fluorescent yellow-green color, and the ASGreen trap was a green color. Spectral reflectance measurements were taken to categorize the color (wavelength) spectrum of each trap. Percent reflectance in the green and yellow wavelength regions was similar among the ASYellow, GLYellow, RWYellow and ASACP traps. Three of the six sticky traps (GLYellow, RWYellow and MGGreen) were treated with a traditional gluey adhesive material. The other three traps were treated with No Mess Sticky Card adhesive, a hot-melted, pressuresensitive adhesive material. Trapping studies were conducted in Florida and Texas during AprileMay comparing four of the traps and during SeptembereOctober comparing all six traps. Data collected during AprileMay indicated there were no significant differences in numbers of adults captured on ASGreen, ASYellow, ASACP and GLYellow traps. In seven comparisons of all six traps during SeptembereOctober, the GLYellow and RWYellow traps each captured significantly fewer adults in one comparison, the MGGreen trap captured fewer adults in two comparisons, and the ASGreen trap captured fewer in three comparisons. There was no evidence that any one of the six traps would be best at detecting psyllids when adult populations are scarce. There was no significant difference between the two adhesive materials with respect to numbers of adults captured on traps. Published by Elsevier Ltd.

Phenotypic plasticity may be critical for nutrient-limited organisms that allocate ingested nutrients to the competing demands of reproduction and survivorship. Leafhoppers that feed on xylem fluid allow assessment of plasticity in response to the constant selective pressure of nutritional inadequacy. We examined feeding behavior (host selection and consumption rates) and nutrient allocation (fecundity, change in body mass and composition) of the xylem fluid-feeding leafhopper Homalodisca vitripennis (Hemiptera:Cicadellidae) on ten genotypes of related Prunus germplasm when adults first seasonally appear, and later during population peaks, to examine the effects of genotypes and season on plasticity of life history and behavioral traits. Behavior and resource allocation to life history traits were both mediated by xylem nutrients, although nutrients impacting behavior differed from those mediating life history. Host selection and consumption varied with genotype between June and July, yet behavior consistently reflected concentrations of dietary glutamine. Resource allocations also increased linearly with nutrient concentrations, but were best correlated to ingested essential amino acids rather than glutamine. Body mass and composition were highly correlated to dietary essential amino acids in June; 6 weeks later, fecundity was instead proportional to essential amino acids. The discrepancy in nutrients which impact behavior versus those mediating life history may explain the weak preference-performance linkage documented for many insects. The demarcation in allocating resources to biomass in June to fecundity in July suggests increased allocation to reproduction during periods of nutrient stress as predicted by the theory of optimal resource allocation; other contributing biotic and abiotic factors are also discussed.

Safe and effective tactics are needed for control of the lesser peachtree borer, Synanthedon pictipes (Grote & Robinson), which is a major pest of stone fruits (Prunus spp) in eastern North America. Virulence of the entomopathogenic nematode, Steinernema carpocapsae (Weiser), to S. pictipes has been demonstrated in the laboratory. However, achieving field efficacy has been difficult because S. pictipes attacks the tree aboveground where nematodes are subjected to damaging environmental conditions, e.g., UV radiation and desiccation. We investigated the potential of various formulations to improve the efficacy of aboveground applications. First, we screened five potential adjuvants at 2%, 20%, and 40% concentrations in water for toxicity to S. carpocapsae in the laboratory: Anti-Stress, Moisturin®, Nu-Film®, Shatter-Proof, and Transfilm®. In general, the adjuvants did not adversely affect nematode survival except at the highest rate. Subsequently, Shatter-Proof was tested in field trials in 2008 and 2009. S. carpocapsae was applied alone or with Shatter-Proof to peach limbs pre-infested with S. pictipes larvae. Furthermore, the experiments included the following treatments: S. carpocapsae followed by a post-application covering of latex paint, moistened diaper, or a gel spray (Barricade®). Controls of water-only, or water plus Shatter-Proof, Barricade®, or paint (without nematodes) were also included. The nematodes-only treatment failed to reduce S. pictipes survival relative to the water-only control in either year. Additionally, the nematode treatments with Shatter-Proof or paint did not differ from nematodes-only, water-only or their respective control treatments without nematodes. The diaper treatment with nematodes showed some potential as an efficacy enhancer (e.g., insect survival was reduced relative to nematodes-only in one year). In contrast, in both years, nematodes plus Barricade® reduced S. pictipes relative to the controls and the nematodes-only treatment; survival in the Barricade® treatment was 30% and 0% in 2008 and 2009, respectively. We conclude that nematode treatments followed by application of a sprayable gel such as Barricade® can enhance control of S. pictipes and possibly other aboveground pests as well.

Generally, microbial control agents such as entomopathogenic nematodes are applied in a curative manner for achieving pest suppression; prophylactic applications are rare. In this study, we determined the ability of two Steinernema carpocapsae strains (All and Hybrid) to prophylactically protect peach trees from damage caused by the peachtree borer, Synanthedon exitiosa , which is a major pest of stone fruit trees in North America. In prior studies, the entomopathogenic nematodes S. carpocapsae and Heterorhabditis bacteriophora caused field suppression when applied in a curative manner to established S. exitiosa populations. In our current study, nematodes were applied three times (at 150,000–300,000 infective juveniles/tree) during September and October of 2005, 2006, and 2007. A control (water only) and a single application of chlorpyrifos (at the labeled rate) were also made each year. The presence of S. exitiosa damage was assessed each year in the spring following the treatment applications. Following applications in 2006, we did not detect any differences among treatments or the control (possibly due to a low and variable S. exitiosa infestation of that orchard). Following applications in 2005 and 2007, however, the nematode and chemical treatments caused significant damage suppression. The percentage of trees with S. exitiosa damage in treated plots ranged from 0% damage in 2005 to 16% in plots treated with S. carpocapsae (Hybrid) in 2007. In control plots damage ranged from 25% (2005) to 41% (2007). Our results indicate that nematodes applied in a preventative manner during S. exitios’ s oviposition period can reduce insect damage to levels similar to what is achieved with recommended chemical insecticide treatments.