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The tarnished plant bug, Lygus lineolaris (TPB), (Palisot de Beauvois), and the western tarnished plant bug (WTPB), Lygus hesperus, Knight, are major agricultural pests that cause significant damage to a wide range of crops in the southeastern and southwestern United States. Flonicamid (commercial name: Carbine 50WG) is generally effective against various sap-feeding pests, including both L. hesperus and L. lineolaris. This study evaluated the toxicity of flonicamid on third-instar nymphs and adults of both Lygus species under laboratory conditions. Two bioassay methods were used: spray application to assess both contact and oral toxicity, and dipping to evaluate oral toxicity. Results showed that L. hesperus was significantly more susceptible to flonicamid than L. lineolaris across both bioassay methods. While no significant differences in toxicity were observed between spray and dipping assays, third-instar nymphs exhibited significantly higher sensitivity than adults in both species. The addition of piperonyl butoxide (PBO), a known inhibitor of cytochrome P450-monooxygenases (P450s), significantly enhanced the toxicity of flonicamid, suggesting that P450 enzyme plays a critical role in its detoxification. Sublethal exposure to flonicamid also induced increased P450 activity in both species. These findings provide valuable insights into the differences in susceptibility between L. lineolaris and L. hesperus to flonicamid and indicate that P450-mediated detoxification is critical for flonicamid metabolism. Such insights are valuable for early resistance monitoring and optimizing flonicamid application in integrated pest management programs.

Lygus lineolaris is a highly polyphagous pest that impacts key crops such as strawberries, making an understanding of its feeding behavior critical for developing effective management strategies. Using metataxonomy, this study examined the dietary breadth of L. lineolaris in a commercial strawberry field in Quebec, revealing an extensive and diverse omnivorous diet. The multiprimer approach, combined with validation samples, ensured high taxonomic resolution and accuracy. We expanded the documented list of L. lineolaris host taxa to 475, including 441 plants and 34 prey species, with 51 taxa unique to this research, comprising eight new plant hosts and five prey species. Molecular evidence confirmed active ingestion, underscoring its omnivorous behavior with a predominantly herbivorous tendency. Notably, 70% of individuals fed exclusively on plants, 20% exhibited omnivory, and only 4% were strictly zoophagous. To quantify the level of phytozoophagy in omnivorous species, we propose a novel coefficient of omnivory (CO), calculated as CO = P /( P + Z), where P and Z represent the number of individuals with molecular evidence of phytophagy and zoophagy, respectively. With a CO of 0.833 (95% CI: 0.77–0.90), L. lineolaris demonstrates a strong bias toward plant feeding. Diet composition varied seasonally and between sexes, with females showing increased zoophagy during reproductive periods. These findings highlight L. lineolaris 's dietary flexibility and resilience, providing critical insights into its feeding ecology and food web interactions to inform targeted integrated pest management strategies tailored to its omnivorous nature.

The mirid bugs Lygus hesperus (Knight) and L. elisus (van Duzee) are key pests of forage, fiber, and fruit crops. Our goals were to identify pheromone components produced by females of both species and to develop practical pheromone dispensers for use in monitoring these pests. Volatiles collected from virgin female L. elisus contained (E)-2-hexenyl butyrate (E2HB) as the major component with lesser amounts of hexyl butyrate (HB) and (E)-4-oxo-2-hexenal (E4OH) (ratio 117.2:100:17.1, respectively), whereas volatiles and solvent extracts from L. hesperus contained HB and E4OH as major components, with only small amounts of E2HB (100:23.6:3.4, respectively in volatiles). Dispensers fabricated from pipette tips released the components at ~10 µg/d in a ratio similar to the loading ratio. These lures were used to optimize the pheromone blends in field studies from 2012 to 2017. Blends of E2HB and E4OH attracted L. elisus, and a 100:60 blend was optimal. Blends of HB and E4OH attracted L. hesperus, and a 100:60 blend was adopted as a base blend. The additions of possible minor components such as (Z)-3-hexenyl butyrate, (E)-2-hexenal, or 1-hexanol did not improve the attraction of L. hesperus. In trials in alfalfa and strawberry, traps baited with blends of HB:E4OH (100:60) were equally or more effective for monitoring L. hesperus than sweep or vacuum samples, with pipette tip dispensers lasting 2–3 weeks under field conditions. The numbers of L. hesperus captured were lower than expected as compared with reports of pheromone trapping for other Lygus spp. Some possible reasons were investigated.

We examined methods of producing day-neutral strawberries in a north temperate climate using alternatives to standard bare-root propagules and clean cultivation between plant rows. Fragaria × ananassa ‘Albion’ were planted in plastic-covered raised beds in Ithaca, NY, USA, for each of the 2022 and 2023 growing seasons. Plants were selected from the following four propagule types from different developmental stages: standard bare-root plants set in early May; bare-root plants started in the greenhouse in February and planted in early May; bare-root plants started in the greenhouse in March and planted in early May; and plug plants set in the field in fall (Aug 2021 and Oct 2022) of the previous year. To determine if pollination could be enhanced, each type of plant was grown in plots in the field with one of the following between rows: bare ground; a diverse flowering groundcover; or exclusion netting on hoops over the strawberry plants when they were flowering. Pollinators visiting strawberries were observed weekly and identified to species when possible. Fruits were collected weekly and marketable and unmarketable yields were measured through the harvest season. Fall-planted plugs produced significantly higher marketable yields than those of other propagule types in both years. Bare-root plants set in early May had the lowest yield. Percent marketable yield varied depending on the growing year because of drastically different weather conditions. There was no evidence that flowering groundcover attracted pollinators to the strawberry plants because strawberries had few pollinator visits, regardless of the surrounding vegetation. Exclusion netting had significantly higher percent marketable yield and total yield than the those of other groundcover types despite lower percent fruit set, likely because of the benefits of tarnished plant bug exclusion.

One of the most economically important pests of cotton, Gossypium hirsutum L., in the midsouth region of the United States is the tarnished plant bug, Lygus lineolaris (Palisot de Beauvois, Hemiptera: Miridae). Tarnished plant bug populations across the region have exhibited widespread resistance to numerous insecticide classes. To minimize late season resistance development, reducing unwarranted applications during the late flowering period can aid in resistance management and potentially reduce input costs. Trials were conducted during 2019 and 2020 to evaluate the impacts of tarnished plant bug populations in the later flowering period of cotton by modifying or terminating threshold regimes during the later weeks of bloom. Results showed that dynamic thresholds altered at the fourth week of bloom or later can reduce the number of late season applications made with no penalty to yield. Additionally, when utilizing a week of bloom termination approach, no significant yield losses were seen when terminating applications after the fourth week of bloom. These data may offer an alternative method to managing tarnished plant bug populations during the later flowering period of midsouth cotton.

Field experiments were conducted in 2016 and 2017 in Tennessee to evaluate the effects of a novel Bacillus thuringiensis (Bt)-transgenic toxin, Bt Cry51Aa2.834_16, on thrips (Thysanoptera: Thripidae) and tarnished plant bug, Lygus lineolaris (Palisot De Beauvois) (Hemiptera: Miridae), in cotton. Protection from thrips injury with the Bt trait was as good or better than an insecticide-based approach. The use of the Bt trait resulted in reduced numbers of immature tarnished plant bug, particularly large nymphs, and partial protection from plant bug injury. Cotton that expressed Bt Cry51Aa2.834_16 had greater yields than the non-Bt isoline when insecticides were not used. Although Bt Cry51Aa2.834_16 reduced the need for insecticide applications, foliar-applied insecticide applications were needed to provide adequate plant protection from tarnished plant bug. The currently recommended treatment thresholds for tarnished plant bug performed similarly well for Bt Cry51Aa2.834_16 and non-Bt isolines. Insecticide applications for tarnished plant bug increased fiber quality, while Bt Cry51Aa2.834_16 had minor effects. The Bt-transgenic toxin Cry51Aa2.834_16 is expected to reduce the need for insecticide applications targeting thrips and tarnished plant bug and could be a valuable addition to an overall insect management program in cotton.

Thrips (Thysanoptera:Thripidae) and tarnished plant bug, Lygus lineolaris (Hemiptera: Miridae), are among the most important insect pests of cotton, Gosssypium hirsutum, in the mid-southern United States. These pests are currently managed primarily by insecticides; however, a new Bt toxin, Cry51Aa2.834_16 is under evaluation for control of thrips and tarnished plant bug. Experiments were conducted to evaluate the behavioral response of thrips and tarnished plant bug to Bt Cry51Aa2.834_16. Adult thrips avoided Bt Cry51Aa2.834_16 cotton in field choice tests and in separate field tests of Bt and non-Bt cotton not treated with insecticides. In a greenhouse choice test, approximately twice as many adult thrips and eggs were found on non-Bt compared with Bt Cry51Aa2.834_16 cotton. Similarly, in a field test of nontreated Bt Cry51Aa2.834_16 and non-Bt cotton, 68% of adult thrips collected were found on non-Bt cotton. In cotton that was not sprayed with insecticides, Bt Cry51Aa2.834_16 did not affect the distribution of tarnished plant bug within the canopy, although more square and flower injury was caused by tarnished plant bug in non-Bt cotton. Adult tarnished plant bug exhibited a nonpreference for diet containing lyophilized Bt Cry51Aa2.834_16 leaves and for excised Bt Cry51Aa2.834_16 squares in choice tests with non-Bt squares.The behavioral responses of these pests when exposed to this new Bt toxin will play a key role in the efficacy and potential resistance management strategies if this new technology is incorporated in an overall cotton insect pest management system.

Lygus hesperus Knight is a polyphagous pest of major concern to numerous cropping systems across western North America. Lygus hesperus exhibits well-documented host preferences which may be used to develop behavioral management strategies for this pest. This study sought to identify plant volatiles that mediate L. hesperus host preferences and assess the potential of those compounds to improve monitoring and management of this pest. Gas chromatography with electroantennographic detection was applied to identify antennally active compounds in headspace extracts from four host plants of varying attractiveness. Y-tube olfactometer assays were then conducted to determine L. hesperus responses to each of these 17 antennally active compounds individually. Six compounds attracted female L. hesperus , and subsequent tests revealed that females were attracted to an equal-parts blend of these six attractive compounds versus clean air, and that this blend was as attractive as flowering Medicago sativa. We then examined L. hesperus attraction to attractive compounds individually and an equal-parts blend of five attractive compounds in the field. An equal-parts blend of five attractive compounds was tested in strawberry, whereas the blend and each individual component were tested in alfalfa. In both field settings, neither the individual compounds nor the blend increased L. hesperus capture rates compared to unbaited control traps. Low attraction in the field could result from a masking effect of background volatiles or the failure to include important compounds in tested blends. It remains important to assess whether the compounds tested in this study may facilitate L. hesperus management in other cropping systems.

The tarnished plant bug, Lygus lineolaris (Palisot de Beauvois), (Hemiptera: Miridae) is considered the most damaging pest of cotton (Gossypium hirsutum L.) in the mid-southern United States, although it is established throughout the United States, southern Canada, and northern Mexico. The introduction of transgenic crops for the control of moths in the Heliothine complex and eradication of the boll weevil, Anthonomus grandis, from much of the United States led to greatly reduced pesticide use in cotton fields, which allowed L. lineolaris to emerge as a new primary pest of cotton in the mid-southern United States. Since the publication of a review by Layton (2000) on damage caused by Lygus lineolaris, many new studies have been published on the changes in host range, population dynamics, sampling methods and thresholds, cultural practices, sex pheromones and attractant blends, novel pesticides and insecticide resistance mechanisms, olfactory and feeding behaviors, introduction of biological control agents, host-plant resistance mechanisms, and new molecular and genetic tools for integrated pest management of Lygus species in cotton and other important crops. Here, we review and discuss the latest developments in L. lineolaris research in the last two decades.

Economically damaging infestations of Lygus lineolaris (Palisot de Beauvois), tarnished plant bug, were sporadic in Virginia and North Carolina cotton before 2010. Given the sudden rise of L. lineolaris as an economic pest in these states, regionally specific management practices (i.e., chemical and cultural control) are needed to help producers protect yield potential while minimizing input costs. Field experiments were conducted in Virginia and North Carolina in 2018 and 2019 to 1) determine the effects of various management practices on L. lineolaris density, plant injury (i.e., square retention, internal boll injury), and lint yield, 2) calculate the economic trade-offs between integrated pest management (IPM) systems approach and current management practices for L. lineolaris in these states, and 3) evaluate economic benefits associated with various sampling thresholds. Lygus lineolaris populations peaked mid-season (i.e., August) during cotton flowering in both states. Weekly scouting and applying foliar insecticides when the current University Extension recommended economic threshold was reached was the most critical management treatment in maximizing economic returns. Additional costs among various IPM practices did not translate into significant yield protection and economic gains. Moreover, there were additional economic benefits associated with protecting glabrous and longer maturing varieties in Virginia. Lygus lineolaris density varied significantly between states; therefore, management recommendations should be modified based on the growing region. Results from this study will be used to create an IPM strategy to help cotton producers effectively manage this insect pest in the Southeast.