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The cranberry weevil Anthonomus musculus Say is a key pest of highbush blueberries (Vaccinium corymbosum L.) and cranberries (Vaccinium macrocarpon Aiton) in the northeastern United States. Previous studies have reported A. musculus adult attraction to traps baited with the aggregation pheromone of the pepper weevil Anthonomus eugenii Cano, likely because these two weevils share similar pheromone blends that differ only in two components. The A. musculus aggregation pheromone contains (Z)‐2‐(3,3‐dimethylcyclohexylidene) ethanol (Z grandlure II), (Z)‐(3,3‐dimethylcyclohexylidene) acetaldehyde (grandlure III), (E)‐(3,3‐dimethylcyclohexylidene) acetaldehyde (grandlure IV) and (E)‐3,7‐dimethyl‐2,6‐octadien‐1‐ol (geraniol); whereas A. eugenii produces a pheromone blend that includes (E)‐2‐(3,3‐dimethylcyclohexylidene) ethanol (E grandlure II) and (E)‐3,7‐dimethyl‐2,6‐octadienoic acid (geranic acid) in addition to the four A. musculus pheromone components. Here, we hypothesized that differences in pheromone composition between these two species influence A. musculus adult attraction to its aggregation pheromone. To test this, we studied the response of A. musculus to its pheromone blend with and without E grandlure II and geranic acid, a commercial A. eugenii pheromone lure and a no‐lure control in highbush blueberry and cranberry fields in New Jersey and Massachusetts, respectively. Regardless of crop type, A. musculus adults were more attracted to their four‐component pheromone blend and the blend plus geranic acid than the commercial A. eugenii pheromone and the no‐lure controls. The A. musculus pheromone blend plus E grandlure II and the A. eugenii pheromone blend also captured more A. musculus adults than the no‐lure control but not compared to the commercial A. eugenii pheromone. Further analysis showed that A. musculus adults are significantly (~27%) less attracted to their pheromone blend if it contains E grandlure II, although the addition of geranic acid did not affect their response. These findings may help guide future efforts towards the development of behaviour‐based tools to monitor and manage A. musculus.

Due to changes in pest management practices, farmers’ reports of severe feeding injury to cranberries, Vaccinium macrocarpon Aiton Ericales: Ericaceae, caused by the cranberry toad-bug, Phylloscelis rubra Ball, have increased in recent years in New Jersey (United States). Currently, however, limited information is available on the effects of P. rubra feeding or density of individuals needed to cause injury to cranberry vines and fruit. In 2015‒2017, we conducted studies to characterize injury to cranberry at a range of P. rubra densities by using cages in a screen-house and field, to establish a correlation between P. rubra density and crop injury in an open field experiment, and to measure the effects of P. rubra injury on the nutritional content (i.e., amounts of macro- and microelements) of cranberry vines. Phylloscelis rubra feeding on cranberry vines produced typical injury symptoms at relatively low densities (i.e., 2 individuals per vine in field cages or

Domestication is predicted to reduce resistance of agricultural crops against insect herbivores; however, its impact on herbivores with different feeding modes and evolutionary histories needs investigation. To this end, we conducted greenhouse experiments to explore the effects of domestication of blueberries (Vaccinium corymbosum), a crop native to North America, on the performance of two chewing herbivores [the native Sparganothis fruitworm (Sparganothis sulfureana (Clemens)) and non-native gypsy moth (Lymantria dispar L.)], and one piercing-sucking herbivore [the blueberry aphid (Illinoia azaleae (Mason))]. Lymantria dispar performed better (i.e., larvae gained more mass, damaged more leaves, and had greater survival) on cultivated V. corymbosum than on its wild counterpart. In contrast, domestication had no impact on the native S. sulfureana larval mass, consumption, and survivorship. Domestication increased survivorship, but not offspring production, of the aphid I. azaleae. To examine changes in plant chemistry due to domestication, we measured phenolic and nutrient (macro- and micro-elements) content in wild and cultivated V. corymbosum leaves. Although there were no differences in total phenolic content, two compounds were absent, while two were at lower and one at higher concentration in domesticated than in wild plants. Wild V. corymbosum leaves had higher amounts of phosphorus, sulfur, and sodium than cultivated leaves; the opposite was found for aluminum. While our findings provide support for the ‘plant domestication-reduced defense’ hypothesis, the effects of domestication were dependent on feeding modes and adaptations of the herbivores such that the non-native chewing species was more positively affected than the chewing and the piercing-sucking natives.

Methyl salicylate (MeSA) is an herbivore-induced plant volatile (HIPV) known to attract the natural enemies of herbivores in agro-ecosystems, however, whether this attraction leads to an increase in natural enemy functioning, i.e., predation, remains largely unknown. Here, we monitored for 2 years (2011&ndash, 2012) the response of herbivores and natural enemies to MeSA lures (PredaLure) by using sticky and pitfall traps in cranberry bogs. In addition, European corn borer, Ostrinia nubilalis, egg masses were used to determine whether natural enemy attraction to MeSA leads to higher predation. In both years, MeSA increased adult hoverfly captures on sticky traps and augmented predation of O. nubilalis eggs. However, MeSA also attracted more phytophagous thrips and, in 2012, more plant bugs (Miridae) to sticky traps. Furthermore, we used surveillance cameras to record the identity of natural enemies attracted to MeSA and measure their predation rate. Video recordings showed that MeSA lures increase visitation by adult lady beetles, adult hoverflies, and predatory mites to sentinel eggs, and predation of these eggs doubled compared to no-lure controls. Our data indicate that MeSA lures increase predator attraction, resulting in increased predation, thus, we provide evidence that attraction to HIPVs can increase natural enemy functioning in an agro-ecosystem.

This 2-year study (2013&ndash, 2014) assessed the efficacy of an odor-baited &ldquo, trap bush&rdquo, approach to aggregate plum curculio, Conotrachelus nenuphar, adult injury, i.e., number of oviposition-scared fruit, in four commercial highbush blueberry farms in New Jersey (USA). In each farm, we compared fruit injury in bushes baited with grandisoic acid and benzaldehyde along the perimeter of trap-bush plots versus unbaited bushes in control plots. We also measured the amount of fruit injury in neighboring bushes (i.e., spillover effect) and in the plots&rsquo, interior. In both years, the amount of fruit injury by C. nenuphar adults was greater on and near odor-baited bushes in trap-bush plots compared with those on and near unbaited bushes in control plots, indicative of aggregation. Injury in unbaited bushes neighboring trap bushes was often greater than unbaited bushes in control plots, providing some evidence for a spillover effect. However, no difference in fruit injury was found between interior trap-bush and control plots. Therefore, odor-baited trap bushes can be used in blueberries to manipulate C. nenuphar foraging behavior, i.e., aggregate adults, without compromising injury in field interiors. Under this approach, insecticides could then be targeted at only a few (perimeter-row) bushes within fields rather than entire fields.

The cranberry weevil, Anthonomus musculus Say (Coleoptera: Curculionidae), is a key (univoltine) pest of highbush blueberries in the northeast United States. To date, however, no trapping system has been developed to successfully monitor this pest. In 2012–2014, studies were conducted in commercial highbush blueberry farms in New Jersey to 1) evaluate the efficacy of various commercially available traps, designed for other weevil species (e.g., pepper weevil, plum curculio, boll weevil, red palm weevil, and black vine weevil), in capturing A. musculus adults; 2) test whether the relative location of traps within the blueberry canopy affects adult captures and 3) determine the effects of different colored (yellow, white, green, red, blue, brown, and black) sticky traps on weevil captures. For a comparison with existing techniques, we also monitored the number of overwintered adult weevils on blueberry bushes using beat sheet sampling. Of all traps and colors tested, the most A. musculus adults were caught on yellow sticky traps and more adults were captured when these traps were placed at the bottom half of the blueberry canopy, i.e., 0.5–1.0 m above ground. Most weevils were caught on colored traps late in the season (i.e., during bloom), which corresponds mostly to the second (summer) adult generation. Thus, number of overwintered adults caught on traps did not correlate with those on bushes. Although our study identified traps that can be used to capture A. musculus adults, these traps alone (i.e., without semiochemicals) have so far limited applicability for monitoring overwintered adult weevils in highbush blueberries.

Sparganothis sulfureana Clemens is a severe pest of cranberries in the Midwest and northeast United States. Timing for insecticide applications has relied primarily on calendar dates and pheromone trap-catch; however, abiotic conditions can vary greatly, rendering such methods unreliable as indicators of optimal treatment timing. Phenology models based on degree-day (DD) accrual represent a proven, superior approach to assessing the development of insect populations, particularly for larvae. Previous studies of S. sulfureana development showed that the lower and upper temperature thresholds for larval development were 10.0 and 29.9°C (49.9 and 85.8°F), respectively. We used these thresholds to generate DD accumulations specific to S. sulfureana, and then linked these DD accumulations to discrete biological events observed during S. sulfureana development in Wisconsin and New Jersey cranberries. Here, we provide the DDs associated with flight initiation, peak flight, flight termination, adult life span, preovipositional period, ovipositional period, and egg hatch. These DD accumulations represent key developmental benchmarks, allowing for the creation of a phenology model that facilitates wiser management of S. sulfureana in the cranberry system.

Sparganothis sulfureana Clemens is a severe pest of cranberries in the Midwest and northeast United States. Timing for insecticide applications has relied primarily on calendar dates and pheromone trap-catch; however, abiotic conditions can vary greatly, rendering such methods unreliable as indicators of optimal treatment timing. Phenology models based on degree-day (DD) accrual represent a proven, superior approach to assessing the development of insect populations, particularly for larvae. Previous studies of S. sulfureana development showed that the lower and upper temperature thresholds for larval development were 10.0 and 29.9°C (49.9 and 85.8°F), respectively. We used these thresholds to generate DD accumulations specific to S. sulfureana, and then linked these DD accumulations to discrete biological events observed during S. sulfureana development in Wisconsin and New Jersey cranberries. Here, we provide the DDs associated with flight initiation, peak flight, flight termination, adult life span, preovipositional period, ovipositional period, and egg hatch. These DD accumulations represent key developmental benchmarks, allowing for the creation of a phenology model that facilitates wiser management of S. sulfureana in the cranberry system.

The plum curculio, Conotrachelus nenuphar (Herbst), is a well known pest in apple and peach orchards, but it also is capable of having an economic impact in highbush blueberries. Host phenology and plum curculio oviposition patterns were determined on four highbush blueberry cultivars differing in fruit maturation period. Numbers of oviposition scars were higher on early- ('Weymouth') and mid-season ('Duke' and 'Bluecrop') blueberries than on late-season 'Elliott' in 2001, 2002, and 2003. In 2002, eggs were first present on the three earliest cultivars 21 d before those on 'Elliott', whereas eggs were found on 'Elliott'40 d after the last sample with eggs for the other three cultivars. The pattern of host phenology and infestation levels suggested that plum curculio oviposition synchronizes well with the availability of suitable fruit for oviposition on early and mid-season cultivars compared with a late-season cultivar of highbush blueberries. The implications of a transition to use of reduced-risk insecticides are discussed in relation to plum curculio management.