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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.

Numerous studies have reported a diversity of stressors that may explain continental-scale declines in populations of native pollinators, particularly those in the genus Bombus. However, there has been little focus on the identification of the local-scale dynamics that may structure currently impoverished Bombus communities. For example, the historically diverse coastal-zone communities of New England (USA) now comprise only a few species and are primarily dominated by a single species, B.&nbsp, impatiens. To better understand the local-scale factors that might be influencing this change in community structure, we examined differences in the presence of parasites in different species of Bombus collected in coastal-zone communities. Our results indicate that Bombus species that are in decline in this region were more likely to harbor parasites than are B. impatiens populations, which were more likely to be parasite-free and to harbor fewer intense infections or co-infections. The contrasting parasite burden between co-occurring winners and losers in this community may impact the endgame of asymmetric contests among species competing for dwindling resources. We suggest that under changing climate and landscape conditions, increasing domination of communities by healthy, synanthropic Bombus species (such as B. impatiens) may be another factor hastening the further erosion of bumble bee diversity.

2017-2018 Belmont Forum and BiodivERsA joint call for research proposals, under the BiodivScen ERA-Net COFUND programme, and with the funding organisations AEI, NWO, ECCyT and NSF Funding information, Allen-Perkins A, Magrach A, Dainese M, Garibaldi LA, Kleijn D, Rader R, Reilly JR, Winfree R, Lundin O, McGrady CM, Brittain C, Biddinger DJ, Artz DR, Elle E, Hoffman G, Ellis JD, Daniels J, Gibbs J, Campbell JW, Brokaw J, Wilson JK, Mason K, Ward KL, Gundersen KB, Bobiwash K, Gut L, Rowe LM, Boyle NK, Williams NM, Joshi NK, Rothwell N, Gillespie RL, Isaacs R, Fleischer SJ, Peterson SS, Rao S, Pitts-Singer TL, Fijen T, Boreux V, Rundlöf M, Viana BF, Klein AM, Smith HG, Bommarco R, Carvalheiro LG, Ricketts TH, Ghazoul J, Krishnan S, Benjamin FE, Loureiro J, Castro S, Raine NE, de Groot GA, Horgan FG, Hipólito J, Smagghe G, Meeus I, Eeraerts M, Potts SG, Kremen C, García D, Miñarro M, Crowder DW, Pisanty G, Mandelik Y, Vereecken NJ, Leclercq N, Weekers T, Lindstrom SAM, Stanley DA, Zaragoza-Trello C, Nicholson CC, Scheper J, Rad C, Marks EAN, Mota L, Danforth B, Park M, Bezerra ADM, Freitas BM, Mallinger RE, Oliveira da Silva F, Willcox B, Ramos DL, D da Silva E Silva F, Lázaro A, Alomar D, González-Estévez MA, Taki H, Cariveau DP, Garratt MPD, Nabaes Jodar DN, Stewart RIA, Ariza D, Pisman M, Lichtenberg EM, Schüepp C, Herzog F, Entling MH, Dupont YL, Michener CD, Daily GC, Ehrlich PR, Burns KLW, Vilà M, Robson A, Howlett B, Blechschmidt L, Jauker F, Schwarzbach F, Nesper M, Diekötter T, Wolters V, Castro H, Gaspar H, Nault BA, Badenhausser I, Petersen JD, Tscharntke T, Bretagnolle V, Willis Chan DS, Chacoff N, Andersson GKS, Jha S, Colville JF, Veldtman R, Coutinho J, Bianchi FJJA, Sutter L, Albrecht M, Jeanneret P, Zou Y, Averill AL, Saez A, Sciligo AR, Vergara CH, Bloom EH, Oeller E, Badano EI, Loeb GM, Grab H, Ekroos J, Gagic V, Cunningham SA, Åström J, Cavigliasso P, Trillo A, Classen A, Mauchline AL, Montero-Castaño A, Wilby A, Woodcock BA, Sidhu CS, Steffan-Dewenter I, Vogiatzakis IN, Herrera JM, Otieno M, Gikungu MW, Cusser SJ, Nauss T, Nilsson L, Knapp J, Ortega-Marcos JJ, González JA, Osborne JL, Blanche R, Shaw RF, Hevia V, Stout J, Arthur AD, Blochtein B, Szentgyorgyi H, Li J, Mayfield MM, Woyciechowski M, Nunes-Silva P, Halinski de Oliveira R, Henry S, Simmons BI, Dalsgaard B, Hansen K, Sritongchuay T, O'Reilly AD, Chamorro García FJ, Nates Parra G, Magalhães Pigozo C, Bartomeus I

Loss of habitat and chemical use associated with agriculture can cause population declines of wild pollinators. Less is known about the evolutionary consequences of interactions between species used in commercial agriculture and wild pollinators. Given population declines of many wild bee species, it is crucial to understand if commercial queens become established in natural areas, if wild bees visit agricultural fields and have the potential to interact with commercial bees, and if gene flow occurs between commercial and wild bees. We drew on a long-term data set that documents commercial bumble bee (Bombus impatiens) use in New England, and we conducted genetic analyses of foraging B. impatiens from areas with varying intensities of commercial bee use. In agricultural areas with a history of commercial bee use we also sampled bees directly from commercial hives. We found significant genetic differences among foraging B. impatiens and B. impatiens sampled directly from hives (average pairwise F′ST = 0.14), but not among samples of foraging bees from natural areas (average F′ST among foraging bees = 0.002). Furthermore, Bayesian analysis of population structure revealed that foraging bees caught in areas with a history of commercial bee use grouped with samples from natural areas. These results document an agricultural setting where there was no widespread introgression of alleles from commercial bumble bees to wild bumble bees, commercial bumble bees did not become established in natural areas, and wild bees were providing pollination services to crops.

Recent pollinator declines have focused efforts on their conservation which require clear estimates of pollination value to agriculture. Our socio-economic producer surveys and agronomic field research data were used to present a new way of estimating ecosystem service value of native pollinators. Using two regionally important U.S.A. crops, Maine wild blueberry and Massachusetts cranberry as models, we present perceived values of native bee pollinators from both consumer and producers. Wild blueberry’s Replacement Cost (RC) was greater than Attributable Net Income (ANI), since greater rented honey bee stocking densities are required. Attributable Net Income for native bees were similar for wild blueberry ($613/ha) and cranberry ($689/ha). Marginal Net Farm Income (MNFI) from incrementally adding more hives per ha was greater from stocking a third/fourth hive per ha for cranberry ($6,206) than stocking a ninth/tenth hive per ha for wild blueberry ($556), given greater responsiveness of yield, revenue, and profit to using rented honey bee hives in cranberry compared to wild blueberry. Both crops’ producers were only willing to annually invest $140–188/ha in native pollination enhancements on their farms, justifying government support. Consumers are willing to pay ~6.7 times more to support native bees than producers, supporting market-based support for invertebrate conservation.

Currently, light microscopic examination of cell morphology cannot discriminate Crithidia mellificae and Lotmaria passim with 100% certainty. Here, a minor groove-binding (MGB) probe-based multiplex real-time PCR assay was developed for the simultaneous and quantitative detection of C. mellificae and L. passim in honey bees. A conserved Hymenoptera 18S rRNA gene was built in as an internal control that allows accurate detection of PCR inhibition and failure of DNA extraction. The newly developed assay was also applied to field samples. Of 21 honey bee colonies (446 bees) sampled from six counties in both central and eastern Massachusetts, 3 colonies (14.29%) and 8 bees (1.79%) were infected with L. passim, and 1 colony (4.76%) and 1 bee (0.22%) with C. mellificae. Our data showed a low rate of trypanosomatid infection, and L. passim was more prevalent than C. mellificae in honey bee samples in Massachusetts.

Larvae of gall making tipworm feed on and injure the apical meristems of cranberry shoots/uprights, disrupting vegetative growth. The majority of tipworm-injured flowering uprights do not resume vegetative growth via activation of lateral axillary buds (side-shoots) before the onset of dormancy. Furthermore, growth and flowering of uprights that fail to produce side-shoots after injury may be inhibited in the following year. In cranberry, limited availability of total nonstructural carbohydrates during fruit development has been reported. Thus, competition between developing fruit and lateral axillary buds for available resources may suppress vegetative regrowth in tipworm-injured flowering uprights. We carried out deblossoming experiments in the field and greenhouse to determine if presence of developing fruit inhibited the growth of side-shoots in tipworm-injured flowering uprights. We also compared tipworm-injured flowering and vegetative uprights to determine if growth form of an upright influenced regrowth after injury. Removal of flowers from tipworm-injured flowering uprights increased the production of side-shoots in three cultivars of cranberry (Ben Lear, Howes, and Stevens). In addition, more tipworm-injured vegetative uprights resumed growth by producing side-shoots, as compared with flowering uprights (Howes and Stevens). Our results suggest that unequal partitioning of resources between developing fruit and lateral axillary buds inhibits regrowth in tipworm-injured flowering uprights of cranberry.

Understanding the mechanisms by which plants tolerate herbivory is important in the study of insect-plant interactions. In cranberry, current season growth has been identified as the main source of photosynthate for the developing fruits. Feeding injury by larvae of cranberry tipworm, Dasineura oxycoccana Johnson, disrupts the apical growth of cranberry shoots or uprights, but does not impact fruit output. To study the effects of experimentally depleting photosynthate available from sources other than the current season growth on fruit output, we girdled tipworm-injured uprights. This technique enabled us to estimate the contribution of current season growth in supplying photosynthate to developing fruits in tipworm-injured uprights. The mean fruit weight declined by >55% in those tipworm-injured uprights that were limited to photosynthate from only the current season growth (girdled uprights). The result was consistent between two phenologically different cultivars of cranberry, one a native selection from wild cranberry stands (‘Howes’) and the other a hybrid (‘Stevens’). In addition, fruit weight was positively correlated to current season leaf area in the girdled uprights only. These results strongly suggest that physiological integration among the different sources of photosynthate plays a key role in the tolerance of tipworm feeding injury for fruit output in cranberry.

The factors explaining host-associated differentiation (HAD) have not yet been fully characterized, especially in agricultural systems. It is thought that certain characteristics within a system may increase the probability for HAD to occur. These characteristics include relatively long-standing evolutionary relationships between insects and their host plants, endophagy, and allochrony in host-plant phenologies. We assessed the status of these characteristics as well as the presence of HAD in the cranberry fruitworm, Acrobasis vaccinii Riley (Lepidoptera: Pyralidae), a pest associated with blueberry and cranberry in eastern North America. We reveal the occurrence of two distinct populations of A. vaccinii that are allochronically isolated by the phenological stage of their respective host plants (cranberries or blueberries). Laboratory-reared A. vaccinii adults collected from blueberries emerge at least 1 week earlier than adults from cranberries and the antennal sensitivity of adults to host-plant volatiles differs between A. vaccinii collected from blueberry and cranberry. Despite finding characteristics indicative of HAD, we did not detect a genetic signature of HAD in A. vaccinii. These findings suggest that HAD may occur through behavioral and phenological mechanisms before there is sufficient genetic variation to be detected.

Larvae of cranberry tipworm, Dasineura oxycoccana Johnson, disrupt early season growth of cranberry (Vaccinium macrocarpon Aiton) uprights or shoots by feeding on apical meristem tissue. A 2-yr field study was carried out at three different locations to determine the impact of tipworm feeding injury on the reproductive and vegetative growth of two cranberry cultivars ('Howes' and 'Stevens') in Massachusetts. In addition to tipworm-injured and intact control uprights, an artificial injury treatment simulating tipworm feeding was also included. Individual uprights of cranberry exhibited tolerance to natural (tipworm) and simulated apical meristem injury in the current growing season (fruit production) and results were corroborated by a greenhouse study. In the field study, weight of fruit was higher in tipworm-injured uprights as compared with intact control uprights at the sites with Howes. However, majority of injured uprights (tipworm and simulated) did not produce new growth from lateral buds (side-shoots) before the onset of dormancy. In the next growing season, fewer injured uprights resumed growth and produced flowers as compared with intact uprights at two of the three sites. We suggest that multiple-year studies focusing on whole plant response to tipworm herbivory will be required to determine the costs of chronic feeding injury over time.

Studies were conducted to develop an attractant for the cranberry weevil, Anthonomus musculus, a pest of blueberry and cranberry flower buds and flowers in the northeastern United States. In previous studies, we showed that cinnamyl alcohol, the most abundant blueberry floral volatile, and the green leaf volatiles (Z)-3-hexenyl acetate and hexyl acetate, emitted from both flowers and flower buds, elicit strong antennal responses from A. musculus. Here, we found that cinnamyl alcohol did not increase capture of A. musculus adults on yellow sticky traps compared with unbaited controls; however, weevils were highly attracted to traps baited with the Anthonomus eugenii Cano aggregation pheromone, indicating that these congeners share common pheromone components. To identify the A. musculus aggregation pheromone, headspace volatiles were collected from adults feeding on blueberry or cranberry flower buds and analyzed by gas chromatography-mass spectrometry. Three male-specific compounds were identified: (Z)-2-(3,3-dimethyl-cyclohexylidene) ethanol (Z grandlure II); (Z)-(3,3-dimethylcyclohexylidene) acetaldehyde (grandlure III); and (E)-(3,3- dimethylcyclohexylidene) acetaldehyde (grandlure IV). A fourth component, (E)-3,7-dimethyl-2,6-octadien-1-ol (geraniol), was emitted in similar quantities by males and females. The emission rates of these volatiles were about 2.8, 1.8, 1.3, and 0.9 ng/adult/d, respectively. Field experiments in highbush blueberry (New Jersey) and cranberry (Massachusetts) examined the attraction of A. musculus to traps baited with the male-produced compounds and geraniol presented alone and combined with (Z)-3-hexenyl acetate and hexyl acetate, and to traps baited with the pheromones of A. eugenii and A. grandis. In both states and crops, traps baited with the A. musculus male-produced compounds attracted the highest number of adults. Addition of the green leaf volatiles did not affect A. musculus attraction to its pheromone but skewed the sex ratio of the captured adults towards females. Although the role of plant volatiles in host-plant location by A. musculus is still unclear, our studies provide the first identification of the primary A. musculus aggregation pheromone components that can be used to monitor this pest in blueberry and cranberry pest management programs.

1 Although management of the oriental beetle Anomala orientalis (Waterhouse) by mating disruption shows promise across a range of agricultural systems, relatively little is known about aspects of the reproductive biology of this species relevant to its management. We studied the effects of delayed mating on several aspects of the oviposition behaviour and biology of the oriental beetle using females mated in the laboratory at 4–13 days posteclosion. 2 Females exhibited a gradual decline in fecundity with increased age at mating that was largely a function of a decline in duration of the oviposition period, as well as lower female fertility: females mated at 11 days were less likely to lay any fertile eggs. However, egg fertility did not vary with female age at mating. 3 Because mating delay did not affect longevity, females mated at older ages experienced decreased oviposition periods; however, females laid more eggs per day with increased age at mating, which partially offset shorter oviposition periods. 4 A mating delay of ≥ 6 days relative to females mated within the first day of reaching sexual maturity resulted in an approximately 35–50% lower mean fecundity. 5 These results suggest that, for mating disruption to be a successful management tool for the oriental beetle, mating must be prevented rather than delayed. We compare the findings of the present study with the published research on delayed mating in moths and discuss the importance of these results in relation to management of the oriental beetle using female sex pheromones.

We evaluated mortality of Sparganothis sulfureana (Clemens) caused by exposing submerged insects to hypoxic (low oxygen) conditions. Taking advantage of the harvest flood in New Jersey, we measured changes in dissolved oxygen (DO) in a cranberry bog and the mortality of first-instar larvae submerged for 1 d. The DO in floodwater rose to 9.2 ppm during the day, dropped during the night to 7.1 ppm at sunrise, and increased again during the morning. Larval mortality was 3.5 ± 2.1%. In the laboratory, we evaluated the effect of submerging first-instar larvae in water at different DO for 1 d. Larval mortality was similar in all treatments but tended to increase with submergence in water with low DO. When first- through third-instar larvae were submerged in water at 15°C and 6.1 ppm DO for different periods of time, their mortality increased with longer submergence. Although long submergence (9 d) caused substantial mortality of S. sulfureana larvae, especially second and third instars, we conclude that a flood of similar duration will likely not be used because if applied to nondormant vines it could potentially impact the cranberry plant. Two important cautions for future studies were identified: (1) mortality can be substantially overestimated if hypoxia-induced lethargy is mistaken for death and (2) the impact of hypoxia may be underestimated if delayed mortality after removal from the water is not considered.

We evaluated the potential management of oriental beetle, Anomala orientalis (Waterhouse), in cranberry by disruption of communication between the sexes through application of the female sex pheromone deployed from wax disks in 2003 and 2004. Mean weekly catch of males in pheromone traps on each untreated bog minus that on each pheromone-treated bog was significantly greater than zero throughout the male flight period for both years of the experiment. Captures of males in traps placed on the edge of pheromone-treated bogs were intermediate between those on control and treated sites; thus, disruption may be limited a short distance from pheromone-treated plots, and treatment of surrounding areas that harbor beetles may be necessary. We deployed a limited number of tethered virgin females in the field for two nights in 2003; when returned to the laboratory, only females on control sites laid fertile eggs. In 2004, we assessed whether delayed mating occurred in the field by deploying tethered females within soil-filled pots and estimated mating rates over five nights by the presence or absence of fertile eggs within soil samples. Only one female among the treated sites laid fertile eggs, whereas the cumulative percentage of females laying fertile eggs in control sites rose steadily over five nights to 96%. The results of this study suggest the strong potential of mating disruption of oriental beetle in cranberry using retrievable, high-dose, point-source dispensers of pheromone.

Although the frequently large variance in relative male fertilization success when females are mated by more than 1 male has been appreciated for some time, the factors that influence relative paternity are still poorly understood. Recently, experimental evidence that morphology of male genitalia influences fertilization success has been documented in 2 water striders, a dung beetle, and a leaf beetle. We explored the role of male genital morphology in postcopulatory sexual selection in the oriental beetle. We mated females to 2 males in succession and assessed relative paternity by the sterile male technique. Morphology of the male genitalia was found to strongly influence relative paternity but only for the first male to mate. Male body size influenced relative fertilization success as well, but again, only for the first male; surprisingly, smaller males achieved higher paternity when mating first. We also found suggestive evidence that copula duration of both the first and second male to mate influenced paternity. Other factors, including female size and degree of asymmetry of hind tibiae length of males had no effect on relative fertilization success. Our results for the oriental beetle are novel among sperm precedence studies for 2 reasons: 1) traits of the first male appear to be more important in influencing paternity than those of the second, and 2) smaller, not larger, males achieved greater relative paternity. Our results also contribute to the growing body of empirical evidence in support of the hypothesis that male genitalia evolve by postcopulatory sexual selection. Key words: evolution of genitalia, first male priority, genital morphology, sexual selection, sperm precedence. [Behav Ecol]

To evaluate the potential for using postharvest fall floods as a pest management tool, designated sections of several commercial cranberry farms in Southeastern Massachusetts were flooded for 3–4 weeks in September–October. Seeded hibernacula of cranberry fruitworm ( Acrobasis vaccinii ) placed into flooded beds for 3 or 4 weeks had 85% lower moth emergence compared to unflooded beds. Fall flooding may reduce dewberry ( Rubus hispidus ) crown numbers and suppress weed coverage in some situations, but the effects were inconsistent. Fall flooding did not adversely affect percent fruit set, yield, or the new growth of cranberry uprights in the year following the flood. Incorporating fall flooding into commercial farm operations should not be difficult since cranberry growers currently use flooding at other times of year as a standard horticultural practice.

Using bucket traps baited with 2-tetradecanone, the sex pheromone of Hoplia equina LeConte, an important pest of cranberries in Massachusetts, we investigated the effect of trap height, color, pheromone load, and lure aging on male capture, as well as captures of nontarget arthropods including pollinators. Male capture was inversely related to height of traps over the four heights tested (0, 20, 60, and 100 cm). Captures increased with increasing pheromone load over the doses of 0, 100, 300, and 600 μg, but captures at the highest load, 1,000 μg, were not significantly different from 300 or 600 μg. H. equina captures were strongly diurnal, with a flight period spanning ≈6 wk starting in mid-June. Vane color of traps (white, yellow, green, blue, red, black) did not affect H. equina capture but significantly influenced capture of nontargets, including pollinators. A bucket trap with the funnel opening at 20 cm, and green (or red) vanes, baited with 600 μg of 2-tetradecanone, was the optimal design ...

The geographic mosaic theory of coevolution suggests that population spatial structure may have a strong impact on coevolutionary dynamics. Therefore, coevolution must be studied across geographic scales, not just in single populations. To examine the impact of movement rate on coevolutionary dynamics, we developed a spatially explicit model of host–parasitoid coevolution. We described space as a coupled-map lattice and assumed that resistance (defined as the ability of a host to encapsulate a parasitoid egg) and virulence (defined as the successful parasitization of a host) traits were graded and costly. The model explicitly detailed population and evolutionary dynamics. When holding all parameters constant and varying only the movement rate of the host and parasitoid, profoundly different dynamics were observed. We found that fluctuations in the mean levels of resistance and virulence in the global population were greatest when the movement rate of the host and parasitoid was high. In addition, we found that the variation in resistance and virulence levels among neighboring patches was greatest when the movement rates of the host and parasitoid was low. However, as the distance among patches increased, so did the variation in resistance and virulence levels regardless of movement rate. These generalizations did not hold when spatial patterns in the distribution of resistance and virulence traits, such as spirals, were observed. Finally, we found that the evolution of resistance and virulence caused the abundance of hosts to increase and the abundance of parasitoids to decrease. As a result, the spatial distribution of hosts and parasitoids was influenced.

Hoplia equina LeConte (Coleoptera: Scarabaeidae: Melolonthinae) is a beetle pest of cranberry beds in Massachusetts. Larvae feed on the roots of the cranberry plant, reducing yield as well as vine density. The female sex pheromone was identified as 2-tetradecanone. There were eight compounds found in the airborne volatiles collected from females that elicited antennal responses from males. Of the eight compounds tested (nonanal, decanal, dodecanal, 2-dodecanone, 2-tridecanone, 2-tetradecanone, 2-pentadecanone, and 2-hexadecanone), 2-tetradecanone was the only one that attracted male beetles in the field. Combining any of the other seven antennally active compounds with 2-tetradecanone did not increase male capture.

The costs and benefits of food foraging for the insect parasitoid, Phanerotoma franklini Gahan (Hymenoptera: Braconidae), were examined. Feeding benefited P. franklini by increasing longevity, but did not influence egg maturation. Costs of feeding are represented by the time required to locate and consume food. Field observations of starved wasps revealed that wasps spent approximately 25% of their time grazing on substances on the surface of cranberry foliage. However, our initial laboratory tests to determine the value of these substances were inconclusive. We also examined how grazing behavior integrated with host foraging by comparing the attack rate of fed and unfed wasps held under different host densities. While feeding status did not affect the mean attack rate of wasps, starvation enhanced the probability that a wasp will engage in movement over the host plant foliage. We conclude that feeding benefits P. franklini by increasing longevity, that travel time to food sources is likely to be low, and that the observed food-foraging behavior does not appear to influence host-foraging efficiency.

Phagostimulatory effects of pH values of sucrose on Rhagoletis pomonella adults were studied in the laboratory. Flies were standardized for age, diet and food deprivation. Two presentation schemes were employed. The first varied pH value (3.0–10.0) with sucrose concentration kept constant at 40%. The second varied both sucrose concentration (8%, 24% and 40%) and pH value (5.0–8.0). Fly feeding propensity was evaluated by observation of fly acceptance or rejection of sucrose and duration of feeding. When tested on red wooden spheres treated with 40% sucrose, fly feeding acceptance was significantly greater when pH ranged from 5.0 to 8.0, and duration of feeding was significantly longer at pH 6.0–7.0. At pH ≤4.0 or pH ≥8.0, feeding propensity was significantly reduced. Decrease in sucrose concentration significantly increased fly sensitivity to pH. Males were more responsive to varying pH than females. The sucrose pH shown to stimulate maximal feeding response was 6.4. Such information is relevant to formulation improvement of a coating mixture of sucrose and insecticide applied to red spheres as part of apple maggot fly control programs.

A traditional flooding practice showed promise for reducing pesticide use in Massachusetts cranberry beds. The 4-week long spring flood, termed “late water,” checked pressure of two of the most prevalent and severe management problems, cranberry fruitworm (CFW) and fungal finit rots (CFR). Fruit rot generally was equal or lower and infestation of fruitworm was consistently lower at the late water beds compared with unflooded beds, even though no fungicides were used for CFR control (standard practice is two or three applications per season) and insecticide applications for CFW were cut by almost 70%. Although there were no significant reductions in yield in two of the years studied, a significant decline (about 25%) occurred on late water beds in one year for unknown reasons.

Two laboratory experiments, a choice test and observations of individual spider-larva interactions, were conducted to determine how the morphological or behavioral defenses, or both, of larvae may affect spider predation success for 2 genera of spiders [Pardosa (Lycosidae), and Habronattus (Salticidae)] commonly found in Massachusetts cranberry, Vaccinium macrocarpon Aiton, ecosystems. Four species of pest larvae with different potential defenses were offered as prey: a spanworm, Ematurga amitaria Guenee (Lepidoptera: Geometridae); a sawfly, Pristophora idiota Norton (Hymenoptera: Tenthridinae); gypsy moth, Lymantria dispar L. (Lepidoptera: Lymantriidae); and a fruitworm, Sparganothis sulfureana Clemens (Lepidoptera: Tortricidae). In the choice tests, E. amitaria larvae were killed significantly more often than either P. idiota or S. sulfureana larvae. No L. dispar larvae were killed in either experiment, and observations suggested that the long setae of the L. dispar larvae provided defense against spider attack. Observations revealed that behavioral and morphological crypsis was a more effective defense than thrashing and regurgitating when E. amitaria larvae were encountered by either genera of spider and also suggested the presence of a chemical defense(s) in P. idiota larvae. Construction of a retreat in cranberry foliage and wriggling movements by S. sulfureana larvae were highly effective in deterring salticid predation. We conclude that the defensive mechanisms possessed by these larvae may effectively influence prey selection and significantly limit predation by spiders in the cranberry agroecosystem.

In field-cage studies, we investigated how the foraging behavior of tephritid fruit flies is modified by experience immediately prior to release on host plants. We observed females of a relatively monophagous species,Rhagoletis mendax (blueberry maggot fly), an oligophagous species,Rhagoletis pomomella (apple maggot fly), and a polyphagous species,Ceratitis capitata (Mediterranean fruit fly). Just prior to release on a host plant, the following kinds of stimuli were supplied: (1) single oviposition in a host fruit, (2) contact with 20% sucrose, (3) contact with a mixture of protein food (bird feces and sucrose), (4) contact with water, and (5) a walk over a host-plant leaf. When flies foraged on host plants without resources, search was most intensive (as measured by number of leaves visited) following a single oviposition in fruit, but residence time generally was the same following exposure to sugar, protein, and fruit stimuli.Rhagoletis mendax andC. capitata females visited the fewest leaves following exposure to water or host leaves, whereasR. pomonella foraged equally intensively following exposure to food stimuli, water, or leaves. On host plants containing resources (fruit and protein food), a single oviposition dramatically increased the number of females of all three species that found fruit compared to females that received experience with food, water or foliar stimuli. We found no significant effect of recent brief experience with any of the stimuli on subsequent attraction to protein food. Overall,C. capitata exhibited a higher propensity to abandon host plants than eitherR. mendax orR. pomonella. We suggest that this may reflect adaptations to differences in distribution of host plants in nature, strategies of dispersal, and host range.

Diversity and abundance of bee pollinators foraging on cranberry in southeastern Massachusetts were studied from 1990 to 1992. Both collections and observations of bees were used to compare the effects of habitat, bog location and size, and year. Although there was a high diversity of native bee pollinators, the abundance of most was very low except for a few bumble bee species and honey bees. Nonapid bees were more abundant and diverse on abandoned and natural bogs than on cultivated bogs; bumble bees were similarly abundant and diverse in the three habitats; and honey bees were present in large numbers only on cultivated bogs where colonies had been placed. In 199.1, some sites had more bumble bees than honey bees even though colonies were present. Small, cultivated bogs tended to have more native bees than did large, cultivated bogs. Native bee populations seemed to be affected by weather and site attributes such as cropping history and surrounding vegetation. Bumble bees might be useful as managed pollinators of cranberry.

Cranberry tipworm, Dasineura oxycoccana Johnson (a gall-making fly), disrupts normal growth of cranberry (Vaccinium macrocarpon Aiton) by injuring the apical meristem of shoots or uprights. The impact of larval feeding injury on reproductive parameters of cranberry was determined, from one growing season to next, at upright (Maine and Massachusetts, 2008-2009) and plot levels (Massachusetts, 2009-2010 and 2010-2011). We also estimated the proportions of uprights injured because of tipworm feeding at several cranberry production sites (Massachusetts and Maine) and the proportions of uprights that produced flowers and fruits in the next growing season. Tipworm-injured uprights tagged at the end of the growing season did not produce floral-units (following year) across sites in both Massachusetts and Maine. There was significant variation among the sampled sites in the proportions of tipworm-injured uprights and also in the proportions of uprights with flowers in the next growing season (Massachusetts and Maine). A trend was apparent wherein sites with higher tipworm injury levels had relatively lower flowering proportions in the next growing season. However, sites in Massachusetts did not differ in the proportions of uprights that set fruit and in a replicated study, significant reduction in tipworm injury at plot level (using insecticide) did not impact flower and fruit production in the next growing season.

We hypothesized that a “sense of malaise” or impending death as a consequence of deprivation from food for 24 h would cause polyphagous Ceratitis capitata (Weidemann), oligophagous Rhagoletis pomonella (Walsh), and relatively monophagous Rhagoletis mendax Curran flies to “dump” eggs in abnormally large numbers in favored host fruit and be less discriminating against ovipositing in unfavored host fruit. Evidence from tests evaluating propensity to bore into fruit and tests measuring amount of oviposition in fruit over a 3-h period does not support this hypothesis.

Up to this point, quantitative aspects of the resource foraging behavior of tephritid fruit flies have been examined at what has been termed the first level of a four-level hierarchical framework. This framework has been constructed to facilitate an operational approach to investigating foraging behavior within a dynamic, state-variable mode of analysis. First-level examination involves tracking the behavior of tephritids in situations comprised of a single type of essential resource where just a single factor shaping foraging behavior is manipulated experimentally. Here, we investigated the foraging behavior of Rhagoletis pomonella (Walsh) flies at the second operational level in the hierarchy: a semi-natural environment comprised of patches of potted host trees that simultaneously harbored two types of essential resources: food and oviposition sites. Mature, fed females that were marked and released into the center tree of five-tree patches remained significantly longer and laid significantly more eggs over two days in patches containing both food (protein and carbohydrate) and oviposition sites (hawthorn fruit) than in patches containing oviposition sites alone. Our findings lead us to speculate that odor of abundant natural food could result in accumulation of both sexes in species of trees whose fruit emit no attractive odor and are not permanent hosts of R. pomonella, but which could receive eggs and support larval development of temporary populations of food-seeking flies.

Migratory and local bees in Massachusetts were analyzed for seven viruses. Three were detected: black queen cell virus (BQCV), deformed wing virus (DWV), and sacbrood virus (SBV). DWV was most common, followed closely by BQCV and then by SBV. BQCV and SBV were present at significantly higher rates in the migratory bees assayed, bringing into question the impact that these bees have on the health of local bee populations.

A FUNNY THING HAPPENED to me on my way from the letter of invitation to the speaker's lectern. While I was thinking about what I would say, I seemed to encounter articles or letters about the struggles of women and other minorities for professional status in almost everything I read. Did the abundance of articles reflect an increase in media attention to a very old problem, or was I more alert to the type of article because of my involvement in the symposium? Although I have long been aware of women's problems in the working world, having to think about women in science to prepare this presentation I began to notice what might have been slipping past my attention. And, it is only through increased awareness that we can start to solve problems. I hope that this symposium will increase your level of consciousness regarding the problems of women in entomology so that each of you will be involved in the solutions.

Cranberry weevil (Anthonomus musculus Say), a key pest of cranberry (Vaccinium macrocarpon Aiton) in Massachusetts, deposits eggs in unopened flowers and often severs the flower pedicel from the peduncle. The compensatory response of cranberry to simulated cranberry weevil damage was investigated by severing the pedicel of unopened flowers with scissors. When intensity of damage was varied on the cultivar Early Black, complete compensation was observed at three of four sites after removal of 33% of a peduncle's unopened flowers, but a approximately 37% decline in number of fruit and weight of berries per peduncle was observed when 67% of unopened flowers were removed. When timing of damage was varied at sites planted to the cultivar Howes, no differences were observed when 50% of unopened flowers were clipped from a peduncle early versus late in preblossom peduncle growth. However, both the early and late clipping treatments resulted in a 30% decrease in the number and weight of berries per peduncle when compared with the no clipping treatment. These results suggest that cranberry has the ability to tolerate low to moderate levels of weevil damage, but a substantial data base will be required to determine any appropriate changes in threshold recommendations.

Hoplia equina LeConte (Coleoptera Scarabaeidae: Melolonthinae) is a beetle pest of cranberry beds in Massachusetts. Larvae feed on the roots of the cranberry plant, reducing yield as well as vine density. The female sex pheromone was identified as 2-tetradecanone. There were eight compounds found in the airborne volatiles collected from females that elicited antennal responses from males. Of the eight compounds tested (nonanal, decanal, dodecanal, 2-dodecanone, 2-tridecanone, 2-tetradecanone, 2-pentadecanone, and 2-hexadecanone), 2-tetradecanone was the only one that attracted male beetles in the field. Combining any of the other seven antennally active compounds with 2-tetradecanone did not increase male capture.

Parasitism influences many aspects of a host's behavior and physiology. Therefore, parasitism is also likely to influence the competitive ability of the host. Field populations of phytophagous insects are often a mix of parasitized and unparasitized conspecifics and the inclusion of parasitism in their competitive dynamics may alter expected outcomes. We investigated the influence of parasitism by the hymenopteran parasitoid Phanerotoma franklini Gahan on the competitive interactions among larvae of its host Acrobasis vaccinii Riley. We found that parasitized larvae were poorer competitors and required less food to complete development compared to unparasitized larvae. To examine the influence of parasitism on the competitive dynamics of this system, we constructed an individual-based model parameterized with our laboratory data. The model examined the role of resource availability and parasitism rate on larval survival. The model suggests that parasitized larvae (and, hence parasitoids) experience higher levels of mortality from competition than unparasitized larvae. Further, the model also suggests that the decreased consumption of resources by parasitized larvae results in a decline in the occurrence of competition as the parasitism rate increases. We suggest that these observations may be general to many parasitoid–host systems.

The following compounds and (approximate ratios) were identified in sex pheromone gland extracts of femaleAcrobasis vaccinii Riley by comparison of gas chromatography-mass spectrometric traces with those of synthetic standards: (E,Z)-, (Z,E)-, (Z,Z), and (E,E)-8, 10-pentadecadien-l-ol acetates (100:1:2:12), a dodecen-l-ol acetate (8), (Z)-8-, (Z)-9-, and (E)-9-pentadecen-l-ol acetates (3:23:4), two heptadecen-l-ol acetates (4:4), tetradecyl, pentadecyl, hexadecyl, and heptadecyl acetates (3:15:10:8), dodecan-l-ol (6), tetradecan-l-ol (5), and hexadecan-l-ol (23). The amount of (E,Z)-8, 10-pentadecadien-l-ol acetate (E8,Z10-15:Ac) in the extract was about 0.5 ng/female. Electroantennographic analysis of gas chromatographic fractions of female sex pheromone gland extract showed that the fraction containingE8,Z10-15:Ac elicited the greatest response. Alone,E8,Z10-15:Ac failed to elicit upwind flight of males in flight-tunnel tests, and traps baited with it did not catch males in field experiments. WhenE8,Z10-15:Ac was combined with (E)-9-pentadecen-l-ol acetate (100:4), male upwind flight response in flight-tunnel tests was equivalent to those obtained with extract of female sex pheromone glands (synthetic, 62%; natural, 51%), but the percent of males flying upwind that contacted the source was lower (synthetic, 47%; natural, 88%). The lower percent of source contact elicited by the synthetic pheromone could be a result of the difference in isomer ratios of 8,10-15:Ac in the natural and synthetic pheromone or could indicate that the synthetic pheromone is incomplete. Traps baited with the 100:4 combination caught large numbers of males in field experiments.

An intensive study of the use of spring flooding to control pests and reduce chemical inputs in cranberry production began in 1995, following preliminary studies in 1993 and 1994. This 4-week flood, known as late water (LW), has been shown to suppress some insects, mites, and fungi, and to stimulate plant growth. We demonstrated that pesticide use could be reduced or eliminated in the year of the flood and to a lesser extent in the year following the flood. With the use of LW in from 1993 to 1996, cranberry grower participants in our study reduced insecticide sprays by 24% and reduced fungicide applications by 30% compared to standard practice bogs without effect on crop quality. LW increased mortality of Rubus sp. weeds so that their spread in a cranberry bed was checked. However, the weed population did not decrease over time. Effects of the flood on cranberry growth and productivity were examined. With changes in rate and timing of fertilizer inputs, growth was similar to that on control beds. However, following an abnormally mild winter and drought conditions in 1995, crops on LW bogs were reduced, sometimes severely, compared to the controls. Crop was not affected in 1993, 1994, or 1996. On a LW bog, it is possible to reduce insecticide use by up to 60%, fungicide use by up to 50%, and nitrogen use by 30%. Reductions and outcomes vary depending on seasonal conditions but, with careful management and weather monitoring, this practice remains a strong option for a sustainable cranberry production system.

Cranberry tipworm (Dasyneura vaccinii Smith) lays its eggs in the upright tips of cranberry (Vaccinium macrocarpon Ait.) plants. Feeding damage by newly hatched maggots leads to characteristic cupping of leaves in the upright tip. This damage is readily apparent to growers and has led to concern that damaged tips would not form terminal flower buds for the following season. Insecticide sprays and cultural practices intended to control this insect are generally ineffective. While studying the incidence of return bloom in cranberry uprights (Strik, B. C., et al. 1991. HortScience 26:1366-1367) heavy cranberry tipworm injury with little apparent effect on yield was noted. We initiated a three year study to examine the potential for cranberry plants to recover from tipworm injury and found that cranberry plants recover completely (no effect on flower bud production) from tipworm injury as long as the injury occurs before mid-August. Only 25% recovery from late-season infestations was found. However, such infestations seldom affected more than 5% of the upright tips. Based on our data, we calculated a maximum 6% loss of flower buds to cranberry tipworm in a year of high late-season infestations.

In commercial cranberry (Vaccinium macrocarpon Ait.) production, flooding is used as a cultural practice for harvest and for winter protection. In addition, after the withdrawal of the winter flood, cranberry bogs may be reflooded in the spring, a practice known as holding “late water” (LW). This practice was used by early cranberry growers in Massachusetts to avoid spring frost and to promote keeping quality in the harvested fruit. Recently, LW has been “rediscovered” as a cultural tool with the potential for reducing inputs of chemical pesticides and fertilizers. We have begun to document the effects of LW on pest populations and on cranberry plants to provide growers with a solid basis for deciding whether to use this cultural practice. In 1993, 11 LW bogs were studied and compared to control bogs. All of the bogs showed acceptable levels of insect and disease damage on the fruit at harvest. The average number of pesticide applications for the LW bogs vs. controls was 0.9 vs. 2.6 for insecticides and 1.3 vs. 2.8 for fungicides.

The two major determinants in sustainable cranberry production are productivity and preservation of water quality. Productivity and water quality were studied using composted chicken manure (CM) and fish hydrolysate fertilizer (FH). In whole bog field trials, soluble granular fertilizer (SG) was replaced with organic fertilizer. At all locations receiving FH, cranberry yields were maintained or improved. The yield results from bogs receiving the CM were mixed, partially due to the quality of the experimental sites. Based on water samples taken from bogs receiving FH, there was no P output and less NH output than from bogs receiving SG. Leaching properties of CM, FH, and SG in cranberry soils were investigated in the laboratory. Concentrations of N03-, P04-, and K+ were greatest in the leachate from columns receiving SG, indicating that organic fertilizers are less likely to lead to the leaching of nutrients into cranberry bog water.

The dispersion of eggs of the apple maggot fly, Rhagoletis pomonella (Walsh), among fruits sampled from two Crataegus mollis (Torr. et Gr.) Scheele hawthorn trees changed over the season, showing first an aggregated dispersion, subsequently a random dispersion, and finally an even dispersion. We suggest that eggs initially were aggregated because when host fruits were very hard and green (mid-August), females deposited eggs in the few sites that could be penetrated with the ovipositor. After the fruit ripened (September), eggs were dispersed evenly, suggesting that under conditions of abundant suitable fruits, females avoid ovipositing in fruit already containing an egg, probably in response to the host-marking pheromone deposited by females following egg-laying. As a result of the placement of eggs, most ripe fruits contained a single egg, thus larvae should have been assured ample developmental resources and minimal intraspecific interactions. Before fruit ripening, there were no significant distributional differences of eggs between the two trees or between the upper and lower half of the canopy. For the entire season, distribution among the tree quadrants was similar. As the season progressed, differences between the trees and crown levels within one of the trees appeared. We conclude that any dispersion study of a species that uses host discrimination cues should consider population density and comparative quality, quantity, and distribution of suitable available resources, as well as changes that may occur in these parameters over time.

At densities found in nature, competition among larvae of the frugivorous fruit fly Rhagoletis pomonella (Diptera: Tephritidae) was pronounced. In fruits of Crataegus mollis, a small native host of the fly, survivorship dropped sharply when > 1 larva developed per fruit. Multiple infestation also caused decreased size of pupae, which resulted in pro- longed maturation of females and lower daily fecundity. Our findings suggest that inter- ference competition occurs among rival R. pomonella larvae within the same fruit and that older larvae may be competitively dominant. In most instances, when 2 d separated the introduction of two larvae into unpicked fruits of Crataegus oxyacantha, a very small ornamental hawthorn, the first larva pupated while the subsequent larva failed to complete development. Rhagoletis pomonella marks its oviposition site with a contact pheromone. The amount of pheromone deposited following a single egg-laying in C. mollis fruit was sufficient to deter most females from laying more eggs. By avoiding marked fruits in which a larva is already developing, a female may conserve eggs and add measurably to her fitness. Because most C. mollis fruits can support more larvae to puparium formation than they actually do, it appears that the strategy of host marking by females and monopolization of fruit by larvae may leave some fruit resources unexploited.

Using behavioural and electrophysiological assay techniques, we identified the posterior half of the midgut as being a principal site of production of a major component of the oviposition-deterring, fruit-marking pheromone of female Rhagoletis pomonella flies. Following secretion into, and accumulation in, the gut lumen, this component is released, together with other gut contents, in the marking trail deposited during dragging of the ovipositor on the fruit surface after egg-laying, as well as in the faeces. Other components of the pheromone may be produced elsewhere.