Temperature-dependent fecundity and survival data was integrated into a matrix population model t... more Temperature-dependent fecundity and survival data was integrated into a matrix population model to describe relative Drosophila suzukii Matsumura (Diptera: Drosophilidae) population increase and age structure based on environmental conditions. This novel modification of the classic Leslie matrix population model is presented as a way to examine how insect populations interact with the environment, and has application as a predictor of population density. For D. suzukii,we examined model implications for pest pressure on crops. As case studies, we examined model predictions in three small fruit production regions in the United States (US) and one in Italy. These production regions have distinctly different climates. In general, patterns of adult D. suzukii trap activity broadly mimicked seasonal population levels predicted by the model using only temperature data. Age structure of estimated populations suggest that trap and fruit infestation data are of limited value and are insufficient for model validation. Thus, we suggest alternative experiments for validation. The model is advantageous in that it provides stage-specific population estimation, which can potentially guide management strategies and provide unique opportunities to simulate stage-specific management effects such as insecticide applications or the effect of biological control on a specific life-stage. The two factors that drive initiation of the model are suitable temperatures (biofix) and availability of a suitable host medium (fruit). Although there are many factors affecting population dynamics of D. suzukii in the field, temperature-dependent survival and reproduction are believed to be the main drivers for D. suzukii populations.
Brown marmorated stink bug, Halyomorpha halys (Stål), (Hemiptera: Pentatomidae) is an invasive po... more Brown marmorated stink bug, Halyomorpha halys (Stål), (Hemiptera: Pentatomidae) is an invasive polyphagous agricultural and urban nuisance pest of Asian origin that is becoming widespread in North America and Europe. Despite the economic importance of pentatomid pests worldwide, their feeding behavior is poorly understood. Electronically monitored insect feeding (EMIF) technology is a useful tool in studies of feeding behavior of Hemiptera. Here we examined H. halys feeding behavior using an EMIF system designed for high throughput studies in environmental chambers. Our objectives were to quantify feeding activity by monitoring proboscis contacts with green beans, including labial dabbing and stylet penetration of the beans, which we collectively define as 'probes'. We examined frequency and duration of 'probes' in field-collected H. halys over 48 hours and we determined how environmental conditions could affect diel and seasonal periodicity of 'probing' acti...
Temperature-related studies were conducted on Drosophila suzukii Matsumura (Diptera: Drosophilida... more Temperature-related studies were conducted on Drosophila suzukii Matsumura (Diptera: Drosophilidae: Drosophilini). From 10-28°C, temperature had a significant impact on blueberries, Vaccinium corymbosum L. (Ericales: Ericaceae), and cherries, Prunus avium (L.) L. 1755 (Rosales: Rosaceae), important commercial hosts of D. suzukii. Temperature had a significant influence on D. suzukii developmental period, survival, and fecundity, with decreasing developmental periods as temperatures increased to 28°C. At 30°C, the highest temperature tested, development periods increased, indicating that above this temperature the developmental extremes for the species were approached. D. suzukii reared on blueberries had lower fecundity than reared on cherries at all temperatures where reproduction occurred. The highest net reproductive rate (Ro) and intrinsic rate of population increase (rm) were recorded on cherries at 22°C and was 195.1 and 0.22, respectively. Estimations using linear and nonline...
Temperature-dependent fecundity and survival data was integrated into a matrix population model t... more Temperature-dependent fecundity and survival data was integrated into a matrix population model to describe relative Drosophila suzukii Matsumura (Diptera: Drosophilidae) population increase and age structure based on environmental conditions. This novel modification of the classic Leslie matrix population model is presented as a way to examine how insect populations interact with the environment, and has application as a predictor of population density. For D. suzukii, we examined model implications for pest pressure on crops. As case studies, we examined model predictions in three small fruit production regions in the United States (US) and one in Italy. These production regions have distinctly different climates. In general, patterns of adult D. suzukii trap activity broadly mimicked seasonal population levels predicted by the model using only temperature data. Age structure of estimated populations suggest that trap and fruit infestation data are of limited value and are insuffi...
Spotted Wing Drosophila (SWD), Drosophila suzukii (Diptera: Drosophilidae), is a devastating pest... more Spotted Wing Drosophila (SWD), Drosophila suzukii (Diptera: Drosophilidae), is a devastating pest that attacks susceptible stone and small fruit in all major production regions of the United States. D. suzukii first appeared on the west coast of the United States in 2008 and is believed to be native to Southeast Asia. SWD has a serrated ovipositor, allowing it to lay eggs in fully intact susceptible fruit rendering them unmarketable. Growers manage such damage by increased pesticide applications, primarily targeting gravid females to prevent them from ovipositing and damaging fruit. In order to determine whether these applications could be targeted more effectively, we examined the timing of oviposition over a 24 h period. Experimental conditions simulated seasonal daily temperatures swings and photoperiods for Corvallis, Oregon. Reproductive SWD females were exposed to these conditions and were allowed to oviposit into artificial media. We examined oviposition rates at regular inte...
Brown marmorated stink bug, Halyomorpha halys (Stål), (Hemiptera: Pentatomidae) is an invasive po... more Brown marmorated stink bug, Halyomorpha halys (Stål), (Hemiptera: Pentatomidae) is an invasive polyphagous agricultural and urban nuisance pest of Asian origin that is becoming widespread in North America and Europe. Despite the economic importance of pentatomid pests worldwide, their feeding behavior is poorly understood. Electronically monitored insect feeding (EMIF) technology is a useful tool in studies of feeding behavior of Hemiptera. Here we examined H. halys feeding behavior using an EMIF system designed for high throughput studies in environmental chambers. Our objectives were to quantify feeding activity by monitoring proboscis contacts with green beans, including labial dabbing and stylet penetration of the beans, which we collectively define as 'probes'. We examined frequency and duration of 'probes' in field-collected H. halys over 48 hours and we determined how environmental conditions could affect diel and seasonal periodicity of 'probing' acti...
We evaluated five herbivore-induced plant volatiles plus a male-produced pheromone as attractants... more We evaluated five herbivore-induced plant volatiles plus a male-produced pheromone as attractants for adult green lacewings in Washington apple orchards in 2008. We found at least five attractants or combinations of attractants were attractive to the three most abundant green lacewing species in our trials. Chrysopa nigricornis and Chrysopa oculata were attracted to the combination of methyl salicylate and iridodial with iridodial alone being the second best attractant. Chrysoperla plorabunda was found in lower numbers than C. nigricornis and C. oculata, but did exhibit a significant attraction to benzaldehyde. In mid-summer, we added the herbivore-induced plant volatile squalene to the study and found it to be exceedingly attractive, but only to male C. nigricornis. Whether alone or in combination, squalene attracted 4-5-fold more C. nigricornis than any other compound tested. Our data have revealed C. nigricornis to be an abundant orchard predator that can be readily monitored with squalene-baited traps. Despite the obvious promise of HIPVs in biological control programs, we urge caution in their deployment as large-scale attractants, at least until further studies have investigated potential disruption of natural enemy population dynamics.
Temperature-dependent fecundity and survival data was integrated into a matrix population model t... more Temperature-dependent fecundity and survival data was integrated into a matrix population model to describe relative Drosophila suzukii Matsumura (Diptera: Drosophilidae) population increase and age structure based on environmental conditions. This novel modification of the classic Leslie matrix population model is presented as a way to examine how insect populations interact with the environment, and has application as a predictor of population density. For D. suzukii, we examined model implications for pest pressure on crops. As case studies, we examined model predictions in three small fruit production regions in the United States (US) and one in Italy. These production regions have distinctly different climates. In general, patterns of adult D. suzukii trap activity broadly mimicked seasonal population levels predicted by the model using only temperature data. Age structure of estimated populations suggest that trap and fruit infestation data are of limited value and are insufficient for model validation. Thus, we suggest alternative experiments for validation. The model is advantageous in that it provides stage-specific population estimation, which can potentially guide management strategies and provide unique opportunities to simulate stage-specific management effects such as insecticide applications or the effect of biological control on a specific life-stage. The two factors that drive initiation of the model are suitable temperatures (biofix) and availability of a suitable host medium (fruit). Although there are many factors affecting population dynamics of D. suzukii in the field, temperature-dependent survival and reproduction are believed to be the main drivers for D. suzukii populations.
Brown marmorated stink bug, Halyomorpha halys Stål, is an invasive, herbivorous insect species th... more Brown marmorated stink bug, Halyomorpha halys Stål, is an invasive, herbivorous insect species that was accidentally introduced to the United States from Asia. First discovered in Allentown, PA, in 1996, H. halys has now been reported from at least 40 states in the United States. Additional invasions have been detected in Canada, Switzerland, France, Germany, Italy, and Lichtenstein, suggesting this invasive species could emerge as a cosmopolitan pest species. In its native range, H. halys is classified as an outbreak pest; however, in North America, H. halys has become a major agricultural pest across a wide range of commodities. H. halys is a generalist herbivore, capable of consuming Ͼ100 different species of host plants, often resulting in substantial economic damage; its feeding damage resulted in US$37 million of losses in apple in 2010, but this stink bug species also attacks other fruit, vegetable, field crop, and ornamental plant species. H. halys has disrupted integrated pest management programs for multiple cropping systems. Pesticide applications, including broad-spectrum insecticides, have increased in response to H. halys infestations, potentially negatively influencing populations of beneficial arthropods and increasing secondary pest outbreaks. H. halys is also challenging because it affects homeowners as a nuisance pest; the bug tends to overwinter in homes and outbuildings. Although more research is required to better understand the ecology and biology of H. halys, we present its life history, host plant damage, and the management options available for this invasive pest species.
ABSTRACT Brown marmorated stink bug, Halyomorpha halys (Stål) is a highly destructive invasive pe... more ABSTRACT Brown marmorated stink bug, Halyomorpha halys (Stål) is a highly destructive invasive pest of annual and perennial crops in the eastern United States and is an increasing threat to agriculture in the Pacific Northwest. Flight mills were used to examine flight capacity of H. halys in order to better understand its invasive characteristics. Specifically, we examined generational, sexual, and phenotypical effects on flight distance, frequency, velocity, and diel flight patterns of field-collected H. halys from two seasons. There was a clear dichotomy in total flight distance for insects that flew 5 km or less and those that flew more than 5 km in 24 h. The tendency for long distance flight of H. halys changed over the course of a given season, peaking at the end of the growing season. Summer generation H. halys flew farther and faster than overwintered adults, but not as frequently. Males and females had similar numbers of flights, but females went farther. Pre-flight weight of insects was correlated flight activity of adults in terms of speed, frequency, and distance. Overwintered H. halys lost a greater proportion of their pre-flight body weight during the assay than did the summer generation adults. Despite many limitations extrapolating flight mill data to the field, this study nonetheless provided evidence that H. halys has the capacity for long distance flight, particularly in the summer generation. The nutritional status and fat reserves of overwintered versus summer generation adults are discussed as potential explanations for the flight patterns found in this study.
The longevity of adult codling moth (Cydia pomonella (L.) Lepidoptera: Tortricidae) and obliqueba... more The longevity of adult codling moth (Cydia pomonella (L.) Lepidoptera: Tortricidae) and obliquebanded leafroller (Choristoneura rosaceana (Harris) Lepidoptera: Tortricidae) held in shaded vials in the tree canopy was measured during the normal flight periods during 2004 and 2005. In both years all codling moths were dead by 130 degree-days (DD) (21 d) in the spring and 121 DD (8 d) in the summer. On a degree-day basis, data were similar across sex, generation, and year, and a common curve adequately predicted the survival distribution. For the obliquebanded leafroller, there were longevity differences between the sexes, but not between generations or years. Use of empirical quantile-quantile plots showed that the female obliquebanded leafroller lived an average of 32% longer than males. Maximum longevity observed in these studies for obliquebanded leafrollers was 117 DD (11 d) across both generations. The implications of these data for population biology studies and quarantine requirements are discussed.
Temperature-related studies were conducted on Drosophila suzukii Matsumura (Diptera: Drosophilida... more Temperature-related studies were conducted on Drosophila suzukii Matsumura (Diptera: Drosophilidae: Drosophilini). From 10 Ð28ЊC, temperature had a signiÞcant impact on blueberries, Vaccinium corymbosum L. (Ericales: Ericaceae), and cherries, Prunus avium (L.) L. 1755 (Rosales: Rosaceae), important commercial hosts of D. suzukii. Temperature had a signiÞcant inßuence on D. suzukii developmental period, survival, and fecundity, with decreasing developmental periods as temperatures increased to 28ЊC. At 30ЊC, the highest temperature tested, development periods increased, indicating that above this temperature the developmental extremes for the species were approached. D. suzukii reared on blueberries had lower fecundity than reared on cherries at all temperatures where reproduction occurred. The highest net reproductive rate (R o ) and intrinsic rate of population increase (r m ) were recorded on cherries at 22ЊC and was 195.1 and 0.22, respectively. Estimations using linear and nonlinear Þt for the minimum, optimal, and maximum temperatures where development can take place were respectively, 7.2, 28.1, and 42.1ЊC. The r m values were minimal, optimal, and maximal at 13.4, 21.0, and 29.3ЊC, respectively. Our laboratory cultures of D. suzukii displayed high rates of infection for Wolbachia spp. (Rickettsiales: Rickettsiaceae), and this infection may have impacted fecundity found in this study. A temperature-dependent matrix population estimation model using fecundity and survival data were run to determine whether these data could predict D. suzukii pressure based on environmental conditions. The model was applied to compare the 2011 and 2012 crop seasons in an important cherry production region. Population estimates using the model explained different risk levels during the key cherry harvest period between these seasons.
Delay of mating was examined as a possible mechanism for population decreases associated with mat... more Delay of mating was examined as a possible mechanism for population decreases associated with mating disruption for codling moth, Cydia pomonella L., and obliquebanded leafroller, Choristoneura rosaceana (Harris) (Lepidoptera: Tortricidae). We examined the effect of delaying female mating 0, 2, 4, or 6 d while holding male age constant on life table parameters of both species. We found that increasing delays in mating were accompanied by two responses: (1) an increase in the percentage of sterile pairs and (2) a reduction in net reproductive rate and population growth unrelated to sterility. On a percentage basis, obliquebanded leafroller population growth was more strongly affected than codling moth. However, the net fertility rate of obliquebanded leafroller was nearly eight-fold higher than that of codling moth, so that obliquebanded leafroller females that experienced a 4-d delay in mating had nearly the same reproductive rate as codling moth females that experienced no delay. Leslie matrix simulations using life tables with Þeld-based adult longevity estimates showed that codling moth females experiencing Ͼ2-d delay in mating resulted in decreases in population density or extinction within two generations. In contrast, obliquebanded leafroller females delayed Ͻ6 d showed rapid population growth that decreased as female age at mating increased; only the 6-d delay treatment resulted in decreased population levels. Our results indicate that obliquebanded leafroller females must on average experience a much longer delay in mating to signiÞcantly reduce population growth compared with codling moth females, suggesting that delay of mating likely plays a greater role in codling moth mating disruption than for obliquebanded leafroller.
We evaluated five herbivore-induced plant volatiles plus a male-produced pheromone as attractants... more We evaluated five herbivore-induced plant volatiles plus a male-produced pheromone as attractants for adult green lacewings in Washington apple orchards in 2008. We found at least five attractants or combinations of attractants were attractive to the three most abundant green lacewing species in our trials. Chrysopa nigricornis and Chrysopa oculata were attracted to the combination of methyl salicylate and iridodial with iridodial alone being the second best attractant. Chrysoperla plorabunda was found in lower numbers than C. nigricornis and C. oculata, but did exhibit a significant attraction to benzaldehyde. In mid-summer, we added the herbivore-induced plant volatile squalene to the study and found it to be exceedingly attractive, but only to male C. nigricornis. Whether alone or in combination, squalene attracted 4-5-fold more C. nigricornis than any other compound tested. Our data have revealed C. nigricornis to be an abundant orchard predator that can be readily monitored with squalene-baited traps. Despite the obvious promise of HIPVs in biological control programs, we urge caution in their deployment as large-scale attractants, at least until further studies have investigated potential disruption of natural enemy population dynamics.
Temperature-dependent fecundity and survival data was integrated into a matrix population model t... more Temperature-dependent fecundity and survival data was integrated into a matrix population model to describe relative Drosophila suzukii Matsumura (Diptera: Drosophilidae) population increase and age structure based on environmental conditions. This novel modification of the classic Leslie matrix population model is presented as a way to examine how insect populations interact with the environment, and has application as a predictor of population density. For D. suzukii,we examined model implications for pest pressure on crops. As case studies, we examined model predictions in three small fruit production regions in the United States (US) and one in Italy. These production regions have distinctly different climates. In general, patterns of adult D. suzukii trap activity broadly mimicked seasonal population levels predicted by the model using only temperature data. Age structure of estimated populations suggest that trap and fruit infestation data are of limited value and are insufficient for model validation. Thus, we suggest alternative experiments for validation. The model is advantageous in that it provides stage-specific population estimation, which can potentially guide management strategies and provide unique opportunities to simulate stage-specific management effects such as insecticide applications or the effect of biological control on a specific life-stage. The two factors that drive initiation of the model are suitable temperatures (biofix) and availability of a suitable host medium (fruit). Although there are many factors affecting population dynamics of D. suzukii in the field, temperature-dependent survival and reproduction are believed to be the main drivers for D. suzukii populations.
Brown marmorated stink bug, Halyomorpha halys (Stål), (Hemiptera: Pentatomidae) is an invasive po... more Brown marmorated stink bug, Halyomorpha halys (Stål), (Hemiptera: Pentatomidae) is an invasive polyphagous agricultural and urban nuisance pest of Asian origin that is becoming widespread in North America and Europe. Despite the economic importance of pentatomid pests worldwide, their feeding behavior is poorly understood. Electronically monitored insect feeding (EMIF) technology is a useful tool in studies of feeding behavior of Hemiptera. Here we examined H. halys feeding behavior using an EMIF system designed for high throughput studies in environmental chambers. Our objectives were to quantify feeding activity by monitoring proboscis contacts with green beans, including labial dabbing and stylet penetration of the beans, which we collectively define as 'probes'. We examined frequency and duration of 'probes' in field-collected H. halys over 48 hours and we determined how environmental conditions could affect diel and seasonal periodicity of 'probing' acti...
Temperature-related studies were conducted on Drosophila suzukii Matsumura (Diptera: Drosophilida... more Temperature-related studies were conducted on Drosophila suzukii Matsumura (Diptera: Drosophilidae: Drosophilini). From 10-28°C, temperature had a significant impact on blueberries, Vaccinium corymbosum L. (Ericales: Ericaceae), and cherries, Prunus avium (L.) L. 1755 (Rosales: Rosaceae), important commercial hosts of D. suzukii. Temperature had a significant influence on D. suzukii developmental period, survival, and fecundity, with decreasing developmental periods as temperatures increased to 28°C. At 30°C, the highest temperature tested, development periods increased, indicating that above this temperature the developmental extremes for the species were approached. D. suzukii reared on blueberries had lower fecundity than reared on cherries at all temperatures where reproduction occurred. The highest net reproductive rate (Ro) and intrinsic rate of population increase (rm) were recorded on cherries at 22°C and was 195.1 and 0.22, respectively. Estimations using linear and nonline...
Temperature-dependent fecundity and survival data was integrated into a matrix population model t... more Temperature-dependent fecundity and survival data was integrated into a matrix population model to describe relative Drosophila suzukii Matsumura (Diptera: Drosophilidae) population increase and age structure based on environmental conditions. This novel modification of the classic Leslie matrix population model is presented as a way to examine how insect populations interact with the environment, and has application as a predictor of population density. For D. suzukii, we examined model implications for pest pressure on crops. As case studies, we examined model predictions in three small fruit production regions in the United States (US) and one in Italy. These production regions have distinctly different climates. In general, patterns of adult D. suzukii trap activity broadly mimicked seasonal population levels predicted by the model using only temperature data. Age structure of estimated populations suggest that trap and fruit infestation data are of limited value and are insuffi...
Spotted Wing Drosophila (SWD), Drosophila suzukii (Diptera: Drosophilidae), is a devastating pest... more Spotted Wing Drosophila (SWD), Drosophila suzukii (Diptera: Drosophilidae), is a devastating pest that attacks susceptible stone and small fruit in all major production regions of the United States. D. suzukii first appeared on the west coast of the United States in 2008 and is believed to be native to Southeast Asia. SWD has a serrated ovipositor, allowing it to lay eggs in fully intact susceptible fruit rendering them unmarketable. Growers manage such damage by increased pesticide applications, primarily targeting gravid females to prevent them from ovipositing and damaging fruit. In order to determine whether these applications could be targeted more effectively, we examined the timing of oviposition over a 24 h period. Experimental conditions simulated seasonal daily temperatures swings and photoperiods for Corvallis, Oregon. Reproductive SWD females were exposed to these conditions and were allowed to oviposit into artificial media. We examined oviposition rates at regular inte...
Brown marmorated stink bug, Halyomorpha halys (Stål), (Hemiptera: Pentatomidae) is an invasive po... more Brown marmorated stink bug, Halyomorpha halys (Stål), (Hemiptera: Pentatomidae) is an invasive polyphagous agricultural and urban nuisance pest of Asian origin that is becoming widespread in North America and Europe. Despite the economic importance of pentatomid pests worldwide, their feeding behavior is poorly understood. Electronically monitored insect feeding (EMIF) technology is a useful tool in studies of feeding behavior of Hemiptera. Here we examined H. halys feeding behavior using an EMIF system designed for high throughput studies in environmental chambers. Our objectives were to quantify feeding activity by monitoring proboscis contacts with green beans, including labial dabbing and stylet penetration of the beans, which we collectively define as 'probes'. We examined frequency and duration of 'probes' in field-collected H. halys over 48 hours and we determined how environmental conditions could affect diel and seasonal periodicity of 'probing' acti...
We evaluated five herbivore-induced plant volatiles plus a male-produced pheromone as attractants... more We evaluated five herbivore-induced plant volatiles plus a male-produced pheromone as attractants for adult green lacewings in Washington apple orchards in 2008. We found at least five attractants or combinations of attractants were attractive to the three most abundant green lacewing species in our trials. Chrysopa nigricornis and Chrysopa oculata were attracted to the combination of methyl salicylate and iridodial with iridodial alone being the second best attractant. Chrysoperla plorabunda was found in lower numbers than C. nigricornis and C. oculata, but did exhibit a significant attraction to benzaldehyde. In mid-summer, we added the herbivore-induced plant volatile squalene to the study and found it to be exceedingly attractive, but only to male C. nigricornis. Whether alone or in combination, squalene attracted 4-5-fold more C. nigricornis than any other compound tested. Our data have revealed C. nigricornis to be an abundant orchard predator that can be readily monitored with squalene-baited traps. Despite the obvious promise of HIPVs in biological control programs, we urge caution in their deployment as large-scale attractants, at least until further studies have investigated potential disruption of natural enemy population dynamics.
Temperature-dependent fecundity and survival data was integrated into a matrix population model t... more Temperature-dependent fecundity and survival data was integrated into a matrix population model to describe relative Drosophila suzukii Matsumura (Diptera: Drosophilidae) population increase and age structure based on environmental conditions. This novel modification of the classic Leslie matrix population model is presented as a way to examine how insect populations interact with the environment, and has application as a predictor of population density. For D. suzukii, we examined model implications for pest pressure on crops. As case studies, we examined model predictions in three small fruit production regions in the United States (US) and one in Italy. These production regions have distinctly different climates. In general, patterns of adult D. suzukii trap activity broadly mimicked seasonal population levels predicted by the model using only temperature data. Age structure of estimated populations suggest that trap and fruit infestation data are of limited value and are insufficient for model validation. Thus, we suggest alternative experiments for validation. The model is advantageous in that it provides stage-specific population estimation, which can potentially guide management strategies and provide unique opportunities to simulate stage-specific management effects such as insecticide applications or the effect of biological control on a specific life-stage. The two factors that drive initiation of the model are suitable temperatures (biofix) and availability of a suitable host medium (fruit). Although there are many factors affecting population dynamics of D. suzukii in the field, temperature-dependent survival and reproduction are believed to be the main drivers for D. suzukii populations.
Brown marmorated stink bug, Halyomorpha halys Stål, is an invasive, herbivorous insect species th... more Brown marmorated stink bug, Halyomorpha halys Stål, is an invasive, herbivorous insect species that was accidentally introduced to the United States from Asia. First discovered in Allentown, PA, in 1996, H. halys has now been reported from at least 40 states in the United States. Additional invasions have been detected in Canada, Switzerland, France, Germany, Italy, and Lichtenstein, suggesting this invasive species could emerge as a cosmopolitan pest species. In its native range, H. halys is classified as an outbreak pest; however, in North America, H. halys has become a major agricultural pest across a wide range of commodities. H. halys is a generalist herbivore, capable of consuming Ͼ100 different species of host plants, often resulting in substantial economic damage; its feeding damage resulted in US$37 million of losses in apple in 2010, but this stink bug species also attacks other fruit, vegetable, field crop, and ornamental plant species. H. halys has disrupted integrated pest management programs for multiple cropping systems. Pesticide applications, including broad-spectrum insecticides, have increased in response to H. halys infestations, potentially negatively influencing populations of beneficial arthropods and increasing secondary pest outbreaks. H. halys is also challenging because it affects homeowners as a nuisance pest; the bug tends to overwinter in homes and outbuildings. Although more research is required to better understand the ecology and biology of H. halys, we present its life history, host plant damage, and the management options available for this invasive pest species.
ABSTRACT Brown marmorated stink bug, Halyomorpha halys (Stål) is a highly destructive invasive pe... more ABSTRACT Brown marmorated stink bug, Halyomorpha halys (Stål) is a highly destructive invasive pest of annual and perennial crops in the eastern United States and is an increasing threat to agriculture in the Pacific Northwest. Flight mills were used to examine flight capacity of H. halys in order to better understand its invasive characteristics. Specifically, we examined generational, sexual, and phenotypical effects on flight distance, frequency, velocity, and diel flight patterns of field-collected H. halys from two seasons. There was a clear dichotomy in total flight distance for insects that flew 5 km or less and those that flew more than 5 km in 24 h. The tendency for long distance flight of H. halys changed over the course of a given season, peaking at the end of the growing season. Summer generation H. halys flew farther and faster than overwintered adults, but not as frequently. Males and females had similar numbers of flights, but females went farther. Pre-flight weight of insects was correlated flight activity of adults in terms of speed, frequency, and distance. Overwintered H. halys lost a greater proportion of their pre-flight body weight during the assay than did the summer generation adults. Despite many limitations extrapolating flight mill data to the field, this study nonetheless provided evidence that H. halys has the capacity for long distance flight, particularly in the summer generation. The nutritional status and fat reserves of overwintered versus summer generation adults are discussed as potential explanations for the flight patterns found in this study.
The longevity of adult codling moth (Cydia pomonella (L.) Lepidoptera: Tortricidae) and obliqueba... more The longevity of adult codling moth (Cydia pomonella (L.) Lepidoptera: Tortricidae) and obliquebanded leafroller (Choristoneura rosaceana (Harris) Lepidoptera: Tortricidae) held in shaded vials in the tree canopy was measured during the normal flight periods during 2004 and 2005. In both years all codling moths were dead by 130 degree-days (DD) (21 d) in the spring and 121 DD (8 d) in the summer. On a degree-day basis, data were similar across sex, generation, and year, and a common curve adequately predicted the survival distribution. For the obliquebanded leafroller, there were longevity differences between the sexes, but not between generations or years. Use of empirical quantile-quantile plots showed that the female obliquebanded leafroller lived an average of 32% longer than males. Maximum longevity observed in these studies for obliquebanded leafrollers was 117 DD (11 d) across both generations. The implications of these data for population biology studies and quarantine requirements are discussed.
Temperature-related studies were conducted on Drosophila suzukii Matsumura (Diptera: Drosophilida... more Temperature-related studies were conducted on Drosophila suzukii Matsumura (Diptera: Drosophilidae: Drosophilini). From 10 Ð28ЊC, temperature had a signiÞcant impact on blueberries, Vaccinium corymbosum L. (Ericales: Ericaceae), and cherries, Prunus avium (L.) L. 1755 (Rosales: Rosaceae), important commercial hosts of D. suzukii. Temperature had a signiÞcant inßuence on D. suzukii developmental period, survival, and fecundity, with decreasing developmental periods as temperatures increased to 28ЊC. At 30ЊC, the highest temperature tested, development periods increased, indicating that above this temperature the developmental extremes for the species were approached. D. suzukii reared on blueberries had lower fecundity than reared on cherries at all temperatures where reproduction occurred. The highest net reproductive rate (R o ) and intrinsic rate of population increase (r m ) were recorded on cherries at 22ЊC and was 195.1 and 0.22, respectively. Estimations using linear and nonlinear Þt for the minimum, optimal, and maximum temperatures where development can take place were respectively, 7.2, 28.1, and 42.1ЊC. The r m values were minimal, optimal, and maximal at 13.4, 21.0, and 29.3ЊC, respectively. Our laboratory cultures of D. suzukii displayed high rates of infection for Wolbachia spp. (Rickettsiales: Rickettsiaceae), and this infection may have impacted fecundity found in this study. A temperature-dependent matrix population estimation model using fecundity and survival data were run to determine whether these data could predict D. suzukii pressure based on environmental conditions. The model was applied to compare the 2011 and 2012 crop seasons in an important cherry production region. Population estimates using the model explained different risk levels during the key cherry harvest period between these seasons.
Delay of mating was examined as a possible mechanism for population decreases associated with mat... more Delay of mating was examined as a possible mechanism for population decreases associated with mating disruption for codling moth, Cydia pomonella L., and obliquebanded leafroller, Choristoneura rosaceana (Harris) (Lepidoptera: Tortricidae). We examined the effect of delaying female mating 0, 2, 4, or 6 d while holding male age constant on life table parameters of both species. We found that increasing delays in mating were accompanied by two responses: (1) an increase in the percentage of sterile pairs and (2) a reduction in net reproductive rate and population growth unrelated to sterility. On a percentage basis, obliquebanded leafroller population growth was more strongly affected than codling moth. However, the net fertility rate of obliquebanded leafroller was nearly eight-fold higher than that of codling moth, so that obliquebanded leafroller females that experienced a 4-d delay in mating had nearly the same reproductive rate as codling moth females that experienced no delay. Leslie matrix simulations using life tables with Þeld-based adult longevity estimates showed that codling moth females experiencing Ͼ2-d delay in mating resulted in decreases in population density or extinction within two generations. In contrast, obliquebanded leafroller females delayed Ͻ6 d showed rapid population growth that decreased as female age at mating increased; only the 6-d delay treatment resulted in decreased population levels. Our results indicate that obliquebanded leafroller females must on average experience a much longer delay in mating to signiÞcantly reduce population growth compared with codling moth females, suggesting that delay of mating likely plays a greater role in codling moth mating disruption than for obliquebanded leafroller.
We evaluated five herbivore-induced plant volatiles plus a male-produced pheromone as attractants... more We evaluated five herbivore-induced plant volatiles plus a male-produced pheromone as attractants for adult green lacewings in Washington apple orchards in 2008. We found at least five attractants or combinations of attractants were attractive to the three most abundant green lacewing species in our trials. Chrysopa nigricornis and Chrysopa oculata were attracted to the combination of methyl salicylate and iridodial with iridodial alone being the second best attractant. Chrysoperla plorabunda was found in lower numbers than C. nigricornis and C. oculata, but did exhibit a significant attraction to benzaldehyde. In mid-summer, we added the herbivore-induced plant volatile squalene to the study and found it to be exceedingly attractive, but only to male C. nigricornis. Whether alone or in combination, squalene attracted 4-5-fold more C. nigricornis than any other compound tested. Our data have revealed C. nigricornis to be an abundant orchard predator that can be readily monitored with squalene-baited traps. Despite the obvious promise of HIPVs in biological control programs, we urge caution in their deployment as large-scale attractants, at least until further studies have investigated potential disruption of natural enemy population dynamics.
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