Journal of economic entomology最新文献

Fertilizers generally influence the nutritional quality or defense ability of the plants, which can indirectly cause an increase in populations of herbivorous insect pests such as grape phylloxera, Daktulosphaira vitifoliae (Homoptera: Phylloxeridae, Fitch). The effects of nutrient solutions on grape-grape phylloxera interactions were analyzed using five concentrations (nitrogen content: 15, 30, 60, 120, and 180 mg/L) of Hoagland's nutrient solution to irrigate Vitis vinifera L. × Vitis labrusca L. (Kyoho). Life table variables and life history variables showed a hump-shaped or an inverted hump-shaped curve as nutrient input level increased. Sixty microgram per liter treatment resulted in the greatest longevity and egg incubation, shortened the nymph duration and significantly increased the adult lifespan. Overall, both excessive and insufficient nutrient inputs curbed growth and multiplication of D. vitifoliae. These results provide a theoretical basis for vineyards for amending fertilizer inputs to prioritize the prevention and control of this pest.

Florida is the second largest producer of strawberries in the United States. However, the production system faces numerous challenges, especially Scirtothrips dorsalis Hood (Thysanoptera: Thripidae) infestations. Management of this pest involves applying insecticides and use of predatory mites, particularly Amblyseius swirskii Athias-Henriot, Neoseiulus cucumeris Oudemans, and Neoseiulus californicus McGregor (Mesostigmata: Phytoseiidae). Strawberry growers in Florida are concerned about the compatibility of the commercial formulations of insecticides used in strawberry pest management with predatory mites. This study assessed the residual effect of commercial insecticides used in strawberry production on the survival, feeding, and oviposition of the 3 predators. Using Munger cells, predators were exposed to commercial formulations of spinetoram, cyantraniliprole, azadirachtin + pyrethrin, Beauveria bassiana, Cordyceps javanica, capsicum, garlic, and canola oil extracts, and water control. There was a gradual decline in the survival and feeding of predatory mites when exposed to all insecticides. Spinetoram had the highest impact on the survival and feeding of all predators compared to other insecticides, while C. javanica had the lowest impact. Cyantraniliprole and azadirachtin + pyrethrin significantly reduced predator survival after 72 h of exposure, whereas capsicum, garlic, and canola oil extracts caused a similar reduction after 96 h. All predators consumed low proportions of S. dorsalis across all treatments. Oviposition was low in all treatments, with no discernable variation among treatments. These results highlight the potential of using entomopathogenic fungi in conjunction with A. swirskii, N. cucumeris, and N. californicus for the management of S. dorsalis and T. urticae in strawberries.

Wheat stem sawfly (WSS), Cephus cinctus Norton (Hymenoptera: Cephidae), is a major pest of cereal crops throughout the Northern Great Plains of North America. Native parasitoids, Bracon cephi (Gahan) and B. lissogaster Muesebeck (Hymenoptera: Braconidae), play a key role in suppressing WSS populations and limiting associated damage. Smooth brome grass (Bromus inermis Leyss.) serves as a potential trap reservoir for WSS when grown in areas surrounding wheat (Triticum aestivum L.) fields in Montana. Its unique biology allows it to support high WSS infestation while promoting significant larval mortality throughout the growing season. Late-season WSS survivors can then serve as hosts for WSS parasitoids. Our study investigated smooth brome as a host refuge for WSS parasitoids. We measured WSS larval infestation and survival rate inside smooth brome grown within WSS-inclusion cages, finding a maximum infestation of 66.5% and an end-of-year WSS survival of 5.7%. In addition, we collected stems from sites in central and north-central Montana to measure the WSS infestation and parasitoid prevalence in wheat and adjacent smooth brome. WSS infestation was high in both Big Sandy (64.5% smooth brome, 65.7% adjacent wheat) and Moccasin, MT (50.6%, 38.6%). Year-end WSS larval mortality was 43.6% greater in smooth brome compared to adjacent wheat at both field sites, but both hosted similar numbers of WSS parasitoids. This research underscores the importance of smooth brome in providing a sustainable host refuge for WSS parasitoids and highlights its significant role in supporting the economics of wheat cultivation.

We used the Photonic Fence Monitoring Device (PFMD) to evaluate orientation by Musca domestica L. (Diptera: Muscidae), and Calliphora vicina Robineau-Desvoidy (Diptera: Calliphoridae) to the Zevo Flying Insect Trap Model 3. The PFMD's dual cameras record infrared light (IR) reflected from a wavelength-specific fabric; insects do not reflect IR at the same wavelength and are tracked in 3 dimensions as moving objects. The plug-in trap emits ultraviolet and blue light from behind an opaque shield; attracted insects enter the space between the shield and the wall and are trapped on a sticky cartridge facing the wall. An experiment (N = 10) with replicates of approximately 40, 1- to 7-day-old mixed-sex flies of each species was conducted in a 6.1 m3 arena. Prior to turning the trap on, the fly movement was not directed toward the trap on the back wall of the arena, regardless of whether the overhead light was on or off. When the overhead light was off, the mean first catch of both species occurred within 5 min after the trap was turned on, and 33.1% and 41.8% of M. domestica and C. vicina, respectively, were caught. House flies flew toward the trap, many approaching from below, while C. vicina apparently walked or flew outside the field of view of the PFMD until they appeared on the vertical reflective surface, and then walked toward the trap from all directions. Our results show that the Zevo Trap attracts and catches flies, and that the PFMD can be used to track flying and walking flies.

Nanoformulations of essential oils (EOs) improve stability of the active ingredient, and thereby its biological activity and persistence. Because compatibility of EOs with natural enemies is not explored sufficiently, we evaluated the impact of nanoformulations of EOs (aniseed, lemon) or pure products (farnesol) on different activities of the generalist predator Chrysoperla carnea (Stephens) (Neuroptera: Chrysopidae). In dual choice bioassay, chrysopid larvae were significantly attracted to aniseed-treated pepper disks and deterred by farnesol. Larval activities (resting, walking, and preying) on treated leaves infested with Myzus persicae (Sulzer) (Hemiptera: Aphididae) were compared. There were no differences among nanoemulsions, nor aphid consumption varied. We studied the toxicity of nanoformulations to larvae and evaluated their development after contact with treated leaf disks, ingestion of treated artificial diet, and both routes of exposure (application of biopesticides on aphid-infested plants). This is the first evidence of the compatibility of EO nanoformulations with C. carnea by single route of exposure. Whether any effect appeared, it was sublethal. Compounds significantly reduced aphid consumption after 6 h on double route exposure, but this negative short-term effect disappeared as time progressed. Our results showed the optimal biopesticide to apply depends on which biological feature of the natural enemy we targeted. The key element to introduce these nanoemulsions is to match their persistence period on the crop with the release of the appropriate biological stage of C. carnea. This reinforces the fact that the main activities of C. carnea can be substantially maintained in joint application with nanoemulsions of EOs.

The diamondback moth, Plutella xylostella (Linnaeus), is one of the most important insect pests of Brassica crops worldwide. In October 2016, outbreaks of an invasive P. xylostella population and unexpected control failures occurred on broccoli and cauliflower crops throughout all vegetable-growing regions in Arizona. Nineteen populations of Plutella xylostella were collected from 2016 to 2021 from various commercial cauliflower fields in Yuma and Scottsdale, Arizona, and from experimental broccoli plots at the University of Arizona, Yuma Agricultural Center (UAYAC), Yuma, Arizona. Populations collected from the commercial cauliflower fields had been transplanted with seedlings produced in a local Yuma nursery in 2016 and Salinas, CA in 2017 to 2018, whereas experimental broccoli plots were direct seeded. These populations were evaluated for their susceptibility to chlorantraniliprole, spinetoram, emamectin benzoate, and cyantraniliprole. In this study, field rate laboratory bioassays, serial dilution laboratory bioassays, and field efficacy spray experiments were performed. The field rate laboratory bioassay results showed that spinetoram, emamectin benzoate, and cyantraniliprole remained effective at controlling P. xylostella, but chlorantraniliprole did not control P. xylostella at the field rate. Additionally, serial dilution bioassays confirmed significant levels of cyantraniliprole and chlorantraniliprole resistance in the P. xylostella populations collected from transplanted cauliflower fields. However, the results of the multiyear/growing-seasons study monitoring the susceptibility of P. xylostella populations collected from direct-seeded broccoli and field efficacy trials conducted at the UAYAC indicated that the resistance to diamide insecticides was neither uniform nor persistent following the 2016 outbreak. Nevertheless, the risk for P. xylostella resistance in Arizona vegetable-growing regions exists, particularly in Brassica transplants. Therefore, we recommend that Arizona Brassica growers remain vigilant and practice rigorous insecticide resistance management to offset the development of resistance.

Maximum dose bioassays were conducted to assess the efficacy of multiple registered active ingredients for diamondback moth (DBM), Plutella xylostella (L.), control in Georgia and Florida from 2021 to 2023 as a follow-up to an earlier study. Low efficacy (<40% mortality) was recorded for the highest labeled rate of Bacillus thuringiensis var. kurstaki strain ATBS-351 in Georgia, as well as chlorantraniliprole, cyantraniliprole, and cyclaniliprole in Georgia and Florida. The active ingredients with the highest efficacy (>80% mortality) in both states were naled, emamectin benzoate, and spinetoram. Independent analysis of data by state indicated that the efficacy of bifenthrin, chlorantraniliprole, cyantraniliprole, tolfenpyrad, and methomyl was higher in Florida populations than in Georgia populations. In addition, a comparison of these data to a recent DBM maximum dose survey in the same region suggested that these DBM populations have rapidly developed high levels of resistance to cyantraniliprole and cyclaniliprole. This work provides growers in the region with a recent ranking of insecticide efficacy that documents the loss of control for certain active ingredients, which assists pest managers in the planning of ongoing insecticide rotations for DBM resistance management.

Knowledge of the ecology and behavior of biological control agents is essential for their effective use in biocontrol and Integrated Pest Management (IPM) programs. There is a lack of information regarding the courtship and mating traits that are crucial for successful mating in biocontrol population of coccinellids. To expand our current understanding in this area, 2 coccinellid species commonly used for the biocontrol of soft-bodied insects, Cryptolaemus montrouzieri (Mulsant) and Propylea quatuordecimpunctata (Linnaeus) (Coleoptera: Coccinellidae), were studied. A quantitative analysis was performed to compare their courtship and mating displays. Key behavioral traits of the precopulatory, copulatory, and postcopulatory phases were investigated. The courtship and mating sequences of C. montrouzieri and P. quatuordecimpunctata were similar to each other. During the mating phase, the key displays were the opening of the elytrae and wings followed by body shaking in C. montrouzieri and leg tapping followed by body shaking in P. quatuordecimpunctata. The mating success of both species was not correlated with any courtship display, such as antennal tapping. Only in C. montrouzieri mounting attempt showed a higher frequency from the backside without affecting male mating success. This research adds baseline knowledge about the courtship and mating behavior of the biocontrol population of coccinellids, contributing to the identification of potentially useful benchmarks (e.g., body shaking, leg tapping) for monitoring prolonged mass-rearing processes, thus reducing mating failures.

In central Canada, surveys for the three invasive (Palearctic) Agriotes species-A. obscurus, A. lineatus, and A. sputator-commonly collect A. pubescens, a North American native (Nearctic) click beetle (Coleoptera: Elateridae) that generally co-occurs with Nearctic A. mancus. Despite the abundance of A. pubescens on farmland, its life history and potential economic impact remain largely unknown. Here, we report the identification and field testing of the A. pubescens sex pheromone. We collected headspace volatiles from a single female beetle on Porapak Q, then extracted the female's pheromone gland, and analyzed aliquots of both Porapak extract and pheromone gland extract by gas chromatographic-electroantennographic detection (GC-EAD) and by GC-mass spectrometry. In GC-EAD recordings of gland extract, two esters-geranyl butanoate and geranyl octanoate-elicited antennal responses from A. pubescens males. In a field experiment in Quebec, traps baited with a 1:1 blend of these esters captured approximately 100× more A. pubescens males than traps baited with a single ester. This is the same trap lure used for capturing A. lineatus. In this experiment, and in a similar one run in British Columbia, heterospecific pheromone components added to conspecific pheromone lures reduced captures of A. mancus, A. sputator, A. lineatus, and A. obscurus by 29%, 96%, 44%, and 71%, respectively. These data indicate that, in North America, lures containing pheromone components of multiple Agriotes congeners may not be optimally attractive to all target species.