No abstract

No abstract

1 Xylosandrus germanus (Blandford) is a key pest of ornamental nursery trees. Ethanol is the most attractive semiochemical known for X. germanus, and its emission from trees represents a primary host-selection cue. Ethanol production is induced by a variety of abiotic and biotic stressors, which could thereby predispose trees to attack by ethanol-responsive ambrosia beetles. 2 To better understand X. germanus host-selection behaviour within ornamental nurseries, a series of experiments examined the influence of flood-stress on the attractiveness and susceptibility of flowering dogwood Cornus florida L. Under field conditions, more X. germanus were attracted to experimentally flood-stressed dogwoods than neighbouring nonflooded controls in 2009, 2010 and 2011. Floodstressed dogwoods were also preferentially attacked in 2009-2011, although no attacks occurred on any of the neighbouring nonflooded trees. 3 Solid-phase microextraction-gas chromatography-mass spectrometry detected ethanol in stem tissue from flooded dogwoods but not nonflooded trees. Acetaldehyde, acetic acid and ethanol were also emitted from the outer bark of flooded dogwoods but not nonflooded trees. 4 These results demonstrate that X. germanus preferentially lands on and attacks physiologically-stressed hosts, and further support the role of ethanol in mediating this interaction. 5 Attacks by X. germanus have previously been suspected to occur on trees viewed as 'apparently-healthy', although the possibility of such trees being in apparentlystressed at the time of attack cannot be ruled out given the results obtained in the present study. Minimizing the impact of stressors known to induce the production of ethanol should be the primary foundation of a management plan for X. germanus and other ethanol-responsive ambrosia beetles.include aesthetic damage to the bark, wilting foliage, branch dieback and profuse basal sprouts. The host range of X. germanus includes more than 200 species worldwide, although deciduous hosts are preferred over coniferous species (Weber & McPherson, 1983). Despite a broad host range, the quality of the host appears to play a critical role in mediating hostselection (Weber & McPherson, 1984;Ranger et al., 2010Ranger et al., , 2012. Previous studies have demonstrated that X. germanus exhibits an efficient olfactory mechanism for distinguishing among differing host qualities and locating hosts based on the

The key to an effective pest management program for the emerald ash borer, Agrilus planipennis Fairmaire (Coleoptera Buprestidae), is a survey program equipped with tools for detecting and delimiting populations. We studied the effects of trap design, color, and placement on the efficacy of sticky traps for capturing the emerald ash borer. There were significant differences in trap catch along a transect gradient from wooded to open field conditions, with most beetles being caught along the edge, or in open fields, 15-25 m outside an ash (Fraxinus spp. L.) (Oleaceae) woodlot. Greater emerald ash borer catch occurred on purple traps than on red or white traps. Traps placed in the mid-canopy of ash trees (13 m) caught significantly more beetles than those placed at ground level. We also describe a new trap design, a three-sided prism trap, which is relatively easy to assemble and deploy.

No abstract

Field-based trapping experiments were conducted in Ohio in 2003, 2004, and 2008 to determine the influence of (-)-alpha-pinene on the attraction of exotic and native ambrosia beetles (Coleoptera: Curculionidae: Scolytinae) to ethanol-baited traps. In 2003 and 2004, we determined the effect of adding an (-)-alpha-pinene ultrahigh release lure (UHR; 2 g/d at 20 degrees C) to traps baited with an ethanol UHR lure (0.39 g/d). FewerAnisandrus (Xyleborus) sayi (Hopkins) and Xyleborinus saxeseni (Ratzeburg) were collected in 2003 and 2004 from traps baited with ethanol UHR plus (-)-alpha-pinene UHR compared with ethanol UHR. (-)-alpha-Pinene also reduced the attraction of Xyloterinus politus (Say) to ethanol-baited traps in 2004. Total captures of Xylosandrus germanus (Blandford) in 2003 were higher in traps baited with ethanol UHR plus (-)-alpha-pinene UHR than in traps with ethanol UHR alone but not in 2004. In 2008, captures were compared among traps baited with eight combinations of ethanol and (-)-a-pinene at both UHR and low release (LR) rates. Release rates for ethanol LR and (-)-alpha-pinene LR were 0.027 and 0.0015 g/d, respectively. (-)-alpha-Pinene UHR and (-)-alpha-pinene LR reduced the attractiveness of ethanol UHR to A. sayi and X. saxeseni. Ethanol UHR was also more attractive than ethanol LR to A. sayi and X. germanus. These findings demonstrate traps baited with ethanol alone are more effective than ethanol plus (-)-alpha-pinene for monitoring ambrosia beetle flight activity in ornamental nurseries. Ethanol release rate is also an important consideration for monitoring purposes.

The exotic ambrosia beetles Xylosandrus crassiusculus (Motschulsky) and Xylosandrus germanus (Blandford) (Coleoptera: Curculionidae: Scolytinae) are serious pests in ornamental tree nurseries. To optimize bottle-traps as a monitoring system for X. crassiusculus and X. germanus in nurseries, we tested whether increasing the rate of commercial ethanol lures improved captures or early detection of these species. Experiments were conducted in Ohio (2008 and 2009) and Virginia (2008), two states that have experienced significant damage from X. crassiusculus, X. germanus, or both. There were four treatments: no-lure (unbaited control), 1-ethanol lure, 2-ethanol lures and 1 + 1-ethanol lures (one lure in the trap and one suspended 0.5 m above the trap). Captures of X. crassiusculus and X. germanus were higher in all ethanol treatments than unbaited controls, and were generally higher in treatments with two lures versus one. There was no difference in beetle captures between the 2-lure and 1 + 1-lure treatments. First detection of X. crassiusculus and X. germanus occurred more consistently in the treatments with two lures than one lure. Xyleborinus saxesenii (Ratzeburg), Anisandrus sayi Hopkins, Hypothenemus dissimilis Zimmermann, and Hypothenemus eruditus Westwood were also more attracted to traps baited with ethanol than unbaited controls. X. saxesenii was captured in higher numbers in the treatments with two lures than one in Virginia but not in Ohio. There was no difference in captures of the other species among ethanol treatments. The current research shows that ethanol release rates influence sensitivity of traps for detecting emergence of overwintered ambrosia beetles.

No abstract