Suchergebnisse

Non-native ambrosia beetles (Coleoptera: Curculionidae), especially Xylosandrus compactus (Eichhoff), Xylosandrus crassiusculus (Motschulsky) and Xylosandrus germanus (Blandford), are destructive wood-boring pests of trees in ornamental nurseries and tree fruit orchards. Previous studies have demonstrated the adults are repelled by verbenone and strongly attracted to ethanol. We tested a "push-pull" semiochemical strategy in Ohio, Virginia and Mississippi using verbenone emitters to "push" beetles away from vulnerable trees and ethanol lures to "pull" them into annihilative traps. Container-grown trees were flood-stressed to induce ambrosia beetle attacks and then deployed in the presence or absence of verbenone emitters and a perimeter of ethanol-baited interception traps to achieve the following treatment combinations: (a) untreated control, (b) verbenone only, (c) ethanol only, and (d) verbenone plus ethanol. Verbenone and ethanol did not interact to reduce attacks on the flooded trees, nor did verbenone alone reduce attacks. The ethanol-baited traps intercepted enough beetles to reduce attacks on trees deployed in Virginia and Mississippi in 2016, but not in 2017, or in Ohio in 2016. Xylosandrus germanus, X. crassiusculus and both Hypothenemus dissimilis Zimmermann and X. crassiusculus were among the predominant species collected in ethanol-baited traps deployed in Ohio, Virginia and Mississippi, respectively. Xylosandrus germanus and X. crassiusculus were also the predominant species dissected from trees deployed in Ohio and Virginia, respectively. While the ethanol-baited traps showed promise for helping to protect trees by intercepting ambrosia beetles, the repellent "push" component (i.e., verbenone) and attractant "pull" component (i.e., ethanol) will need to be further optimized in order to implement a "push-pull" semiochemical strategy. ; USDA Floriculture and Nursery Research Initiative (USDA/FNRI); Horticultural Research Institute (HRI); USDA-ARS National Program 304-Crop Protection and Quarantine [3607-22000-012-00D]; USDA-ARS National Program 305-Crop Production [6062-21430-002-00D]; USDA National Institute of Food and AgricultureUnited States Department of Agriculture (USDA) [SC-1700473] ; Funding for this project was provided by the USDA Floriculture and Nursery Research Initiative (USDA/FNRI); Horticultural Research Institute (HRI); USDA-ARS National Program 304-Crop Protection and Quarantine (Project 3607-22000-012-00D); USDA-ARS National Program 305-Crop Production (Project 6062-21430-002-00D); and USDA National Institute of Food and Agriculture (Project SC-1700473). We thank Jenny Barnett (USDA-ARS), Jenna Zhu (USDA-ARS) and Mary Seward (Hampton Roads AREC) for technical assistance. ; Public domain authored by a U.S. government employee

The majority of wood-boring ambrosia beetles are strongly attracted to ethanol, a behavior which could be exploited for management within ornamental nurseries. A series of experiments was conducted to determine if ethanol-based interception techniques could reduce ambrosia beetle pest pressure. In two experiments, trap trees injected with a high dose of ethanol were positioned either adjacent or 1015 m from trees injected with a low dose of ethanol (simulating a mildly stressed tree) to determine if the high-dose trap trees could draw beetle attacks away from immediately adjacent stressed nursery trees. The high-ethanol-dose trees sustained considerably higher attacks than the low-dose trees; however, distance between the low- and high-dose trees did not significantly alter attack rates on the low-dose trees. In a third experiment, 60-m length trap lines with varying densities of ethanol-baited traps were deployed along a forest edge to determine if immigrating beetles could be intercepted before reaching sentinel traps or artificially stressed sentinel trees located 10 m further in-field. Intercept trap densities of 2 or 4 traps per trap line were associated with fewer attacks on sentinel trees compared to no traps, but 7 or 13 traps had no impact. None of the tested intercept trap densities resulted in significantly fewer beetles reaching the sentinel traps. The evaluated ethanol-based interception techniques showed limited promise for reducing ambrosia beetle pressure on nursery trees. An interception effect might be enhanced by applying a repellent compound to nursery trees in a pushpull strategy. ; USDA Floriculture and Nursery Research Initiative (FNRI) [58-3607-3-984]; USDA-NIFA Evans Allen fund [0232937] ; We thank Josh Basham, Joseph Lampley, Debbie Eskandarnia, and Megan Patton (Tennessee State University [TSU]) for assistance with data collection and beetle identifications. This project was partially funded by the USDA Floriculture and Nursery Research Initiative (FNRI Agreement Number 58-3607-3-984) and USDA-NIFA Evans Allen funding (0232937). ; Public domain authored by a U.S. government employee