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Frankliniella fusca (Hinds) (Thysanoptera: Thripidae) is an early-season cotton pest. Seedlings are injured by larvae, which hatch from eggs oviposited into seedlings and feed on developing plant tissue. Better understanding F. fusca oviposition in cotton may improve their management and address new challenges such as resistance to neonicotinoid seed treatments (NSTs). Cotton seedlings exposed to F. fusca were either cleared and stained to determine egg density and location, or dissected and washed to determine larval distribution. Experiments were conducted in the greenhouse with a susceptible population and field with a NST-resistant population. Eggs of both populations were recovered predominantly in cotyledons. Larvae were more uniformly distributed on seedlings. On NST seedlings, oviposition by the susceptible population was reduced and preference shifted to true leaves. NSTs did not alter egg placement by the resistant population. These findings suggest that injury to cotton seedlings is primarily caused by F. fusca emerging on the cotyledons, and then moving to developing leaves. The oviposition shift in NST plants correlates with how systemic NSTs have been reported to concentrate in cotyledons. This can better inform management tactics in cotton, such as well-timed foliar sprays, which, given the current resistance issue, are needed to maintain effective thrips management. [ABSTRACT FROM AUTHOR]

European corn borer, Ostrinia nubilalis (Hübner), is a major pest of processing snap bean because larvae are contaminants in pods. The incidence of O. nubilalis-contaminated beans has become uncommon in New York, possibly because widespread adoption of Bt field corn has suppressed populations. Snap bean fields located where Bt corn has been intensively grown in space and time may be at lower risk for O. nubilalis than fields located where Bt corn is not common. To manage O. nubilalis infestation risk, growers determine insecticide application frequency in snap bean based on pheromone-trapping information in nearby sweet corn fields; adult activity is presumed equivalent in both crops. Our goal was to determine if corn planting intensity and adult activity in sweet corn could be used to estimate O. nubilalis populations in snap bean in New York in 2014-2015. Numbers of O nubilalis adults captured in pheromone-baited traps located in snap bean fields where corn was and was not intensively grown were similar, suggesting that O. nubilalis does not respond to local levels of Bt corn in the landscape. Numbers of Ostrinia nubilalis captured in pheromone-baited traps placed by snap bean fields and proximal sweet corn fields were not related, indicating that snap bean growers should no longer make control decisions based on adult activity in sweet corn. Our results also suggest that the risk of O. nubilalis infestations in snap bean is low (~80% of the traps caught zero moths) and insecticide applications targeting this pest should be reduced or eliminated. [ABSTRACT FROM AUTHOR]

Ceratocystis fimbriata, the causal agent of sweetpotato black rot, is a pathogen capable of developing and spreading within postharvest settings. A survey of North Carolina sweetpotato storage facilities was conducted to determine the arthropods present and identify potential vectors of C. fimbriata. Sixteen taxonomic categories were recovered, and the genus Drosophila (Diptera: Drosophilidae) accounted for 79% of individuals sampled, with Drosophila hydei being the most abundant species. Behavioral assays were conducted to determine if D. hydei is attracted to C. fimbriata-inoculated roots and if the pathogen could be recovered from external or intornal surfaces of the insect. Flles were released in insect-trapping pitchers containing either C. fimbriata-inoculated or noninoculated roots or Petri dishes. No significant differences in fly number were detected in sweetpotato-baited pitchers; however, significant differences were found in the pitcher baited with a mature C. fimbriata culture. Flies were subjected to washes to determine if viable C. fimbriata was present (internally or externally); washes were plated onto carrot agar plates and observed for the presence of C. fimbriata colonies. Both external and internal washes had viable C. fimbriata inocula with no significant differences, and inoculated sweetpotatoes had a significantly higher number of flies carrying C. fimbriata. This study suggests that D. hydei can carry C. fimbriata from infected sweetpotatoes and move viable C. fimbriata inocula both externally and internally, making this the first report of any Drosophila sp. serving as a potential vector for the Ceratocystis genus. [ABSTRACT FROM AUTHOR]

The revocation of chlorpyrifos tolerances in 2022 left sweetpotato growers without their most important tool to combat a complex of soil-borne root pests that includes wireworms (Coleoptera: Elateridae). Since then, growers have reported increased root damage despite a rapid pivot to pyrethroid-based management systems to replace mechanically incorporated preplant chlorpyrifos broadcast sprays. Our goal was to evaluate the efficacy of alternative insecticide chemistries and application methods to expand the portfolio of management options for wireworms, specifically Conoderus spp. and Melanotus communis (Gyllenhal). We tested (i) insecticidal transplant water drenches and (ii) a foliar spray program targeting adult elaterids. We found that incorporating insecticides into transplant water reduced wireworm damage when compared to untreated transplant water. Our treatments included a recently registered meta-diamide, broflanilide, which represents a promising path to diversify active ingredients and shift away from an overreliance on preplant and post-directed pyrethroid soil sprays. Foliar spray plots had less damage than plots that did not receive foliar sprays. One benefit of adult-focused management is the availability of effective monitoring tools such as sex pheromones and blacklight trapping. Developing a robust adult monitoring program would enable more precise applications of foliar insecticides versus season-long prophylactic soil sprays targeting larvae. Our results demonstrated a significant benefit to both alternative delivery methods. These management alternatives could expand treatment options beyond traditional preplant and post-directed pyrethroid sprays., (© The Author(s) 2024. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. For commercial re-use, please contact reprints@oup.com for reprints and translation rights for reprints. All other permissions can be obtained through our RightsLink service via the Permissions link on the article page on our site—for further information please contact journals.permissions@oup.com.)

We describe experiments that evaluated potential sex pheromone components for 6 North American click beetle species. In field trials in Illinois, South Carolina, North Carolina, and Virginia, male beetles of 6 species were strongly attracted to geranyl butyrate (Agriotes insanus Candèze), 5-methylhexyl (Z)-4-decenoate (Elater abruptus Say), 11-dodecenyl butyrate (Melanotus ignobilis Melsheimer), and limoniic acid (Gambrinus griseus [Palisot de Beauvois], G. rudis [Brown], and G. plebejus [Say]). Collection of E. abruptus in South Carolina represents a new state record. For each species, capture rates varied geographically and temporally, possibly due to differences in local population densities and regional phenology, or the efficiency of different trap designs or trap placement. Structural similarities were observed between the tested attractants and previously identified pheromones of closely related species. For example, males of A. insanus were attracted to geranyl butyrate, analogous to the terpenoid ester pheromones of a number of European congeners. The attractant for E. abruptus, 5-methylhexyl (Z)-4-decenoate, is an analog of the pheromone of its European congener E. ferrugineus L., and the attractant for M. ignobilis, 11-dodecenyl butyrate, is an analog of attractants of European and Asian congeners. Attraction of the 3 Gambrinus species to limoniic acid parallels recent reports of attraction of the congeners G. seminudus (Van Dyke) and G. ursinus (Van Dyke) to this compound, which was originally identified from closely related species of Limonius. Full identifications of additional sex pheromones for elaterid species should provide a more complete picture of the diversities/similarities of the semiochemicals mediating reproductive behaviors of this biologically diverse and taxonomically complex group., (© The Author(s) 2024. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. For commercial re-use, please contact reprints@oup.com for reprints and translation rights for reprints. All other permissions can be obtained through our RightsLink service via the Permissions link on the article page on our site—for further information please contact journals.permissions@oup.com.)

Root-knot nematodes (RKNs, Meloidogyne spp.) are some of the most economically important and common plant parasitic nematodes in North Carolina (NC) cropping systems. Soil samples collected from fields planted with crops rotated with sweetpotato ( Ipomoea batatas [L.] Lam.) in 39 NC counties in 2015 to 2018 were processed at the NC Nematode Assay Laboratory. The occurrence of second-stage juvenile (J2) RKN populations was examined based on collection year, month, county, and previous planted crop. The highest number of RKN-positive samples originated from Cumberland (53%), Sampson (48%), and Johnston (48%) counties. The highest average RKN population density was detected in Sampson (147 J2/500 cm 3 of soil) and Nash (135 J2/500 cm 3 of soil) counties, while Wayne (7 J2/500 cm 3 of soil) and Greene (11 J2/500 cm 3 of soil) counties had the lowest average RKN population density. Meloidogyne enterolobii is a new invasive species that is impacting sweetpotato growers of NC. The host status of an NC population of M. enterolobii , the guava RKN, was determined by examining eggs per gram of fresh root (ER) and the final nematode egg population divided by the initial population egg count (reproductive factor, RF) in greenhouse experiments. This included 18 vegetable, field, and cover crops and weed species. The tomato 'Rutgers' was used as a susceptible control. Cabbage 'Stonehead', pepper 'Red Bull', and watermelon 'Charleston Gray' and 'Fascination' were hosts and had similar mean ER values to the positive control, ranging from 64 to 18,717. Among field crops, cotton, soybean 'P5018RX', and tobacco were hosts with ER values that ranged from 185 to 706. Members of the Poaceae family such as sweet corn ( Zea mays ) and sudangrass ( Sorghum × drummondii ) were nonhosts to M. enterolobii , and the mean ER values ranged from 1.85 to 7. The peanut 'Tifguard' and winter wheat ( Triticum aestivum ) also had lower ER values than the vegetable hosts. Growers should consider planting less susceptible hosts or nonhosts such as peanut, sudangrass, sweet corn, and winter wheat in 2- to 3-year crop rotations to lower populations of this invasive nematode., Competing Interests: The author(s) declare no conflict of interest.