Ruth Hazzard - Academia.edu (original) (raw)
Papers by Ruth Hazzard
Journal of Economic Entomology, Oct 1, 2004
W hen customers flock to markets in search of sweet corn, they want it to be of the highest quali... more W hen customers flock to markets in search of sweet corn, they want it to be of the highest quality--sweet, fresh and worm-free. Yet, in ecological or organic production of sweet corn, achieving worm-free corn is one of
Plant Disease, 1997
To assess the accuracy of remote, real-time mathematical simulations of wetness duration and air ... more To assess the accuracy of remote, real-time mathematical simulations of wetness duration and air temperature, hourly measurements of wetness duration and air temperature at 18 sites in the United States and Canada from May to September 1995 were compared with simulations for these sites provided by SkyBit, Inc. SkyBit simulations of mean, maximum, and minimum daily air temperatures varied from on-site measurements by less than 0.7°C but underestimated the duration of wet periods by an average of 3.4 h/day. At five of six stations tested, SkyBit underestimates of wetness duration were significantly (P < 0.01) larger on days when no rain was measured than on rainy days, indicating that simulations of dew-period duration were much less accurate than simulations of rain-period duration. The vast majority of hours SkyBit misclassified as dry occurred either when entire wet periods were missed (59.3%) or when the onset of a wet period was detected late (28.4%). The results suggest that...
Three Organic Materials Review Institute (OMRI) listed foliar treatments for control of striped c... more Three Organic Materials Review Institute (OMRI) listed foliar treatments for control of striped cucumber beetle in cucumbers were compared at the University of Massachusetts Crops Research and Education Center in South Deerfield, MA. Each material was tested alone and in combination with the other materials. Treatments included spinosad (Entrust 80W), pyrethin (PyGanic EC 5.0), and kaolin clay (Surround WP). Control plots were treated with water. Untreated seeds of 'Marketmore' pickling cucumber were planted in a heated greenhouse on 29 Apr 2009 and transplanted into the field on 27 May using a RCB design with 8 treatments and 4 replicates. Each treatment plot consisted of a 1.22m bed of two rows, 0.46m apart and 4.57m long, separated from other plots by 1.83m. Beds were covered in black plastic with one run of drip irrigation centered between the rows. Treatments were applied on 1, 8, and 15 Jun, using a CO2 R&D backpack sprayer with a flat fan nozzle delivering 19.2 gpa wa...
In 2002 a long-term cucurbit crop systems pest and crop management evaluation was continued at NY... more In 2002 a long-term cucurbit crop systems pest and crop management evaluation was continued at NYSAES Geneva. This project is a continuation of a sweet corn systems project conducted 1995-1999. Systems are located in the same fields as the previous sweet corn evaluation meaning that land has now been managed under the particular systems for 8 years. A team of vegetable experts evaluated four systems for producing cucurbit crops including Conventional, IPM Present, IPM Future, and Organic. Commercial scale plots of cucumbers, melons, zucchini, and pumpkins were grown under these systems and compared on the basis of economic, environmental, and pest control efficacy factors. In addition, demonstrations of the systems were conducted on growers' farms in eastern New York, Ohio, and Massachusetts
Arthropod Management Tests, 2015
, white, savoy) j Brassica oleracea var. capitata cabbage root maggot | Delia radicum crucifer fl... more , white, savoy) j Brassica oleracea var. capitata cabbage root maggot | Delia radicum crucifer flea beetle | Phyllotreta cruciferae 4-(2,2-difluoro-1,3-benzodioxol-4-yl)-1H-pyrrole-3-carbonitrile; methyl N-(2,6-dimethylphenyl)-N-(methoxyacetyl)-D-alaninate; methyl (aE)-2-[[6-(2-cyanophenoxy)-4-pyrimidinyl]oxy]-a-(methoxymethylene)benzeneacetate þ 3-[(2-chloro-5-thiazolyl)methyl]tetrahydro-5-methyl-N-nitro-4H-1,3,5-oxadiazin-4-imine; 4-(2,2-difluoro-1,3-benzodioxol-4-yl)-1H-pyrrole-3-carbonitrile; methyl N-(2,6-dimethylphenyl)-N-(methoxyacetyl)-D-alaninate; methyl (aE)-2-[[6-(2-cyanophenoxy)-4pyrimidinyl]oxy]-a-(methoxymethylene)benzeneacetate þ 3-[(2-chloro-5-thiazolyl)methyl]tetrahydro-5-methyl-N-nitro-4H-1,3,5-oxadiazin-4-imine; (2E)-1-[(6-chloro-3-pyridinyl)methyl]-N-nitro-2-imidazolidinimine; 4-(2,2-difluoro-1,3-benzodioxol-4-yl)-1H-pyrrole-3-carbonitrile; methyl N-(2,6-dimethylphenyl)-N-(methoxyacetyl)-D-alaninate; methyl (aE)-2-[[6-(2-cyanophenoxy)-4-pyrimidinyl]oxy]-a-(methoxymethylene)benzeneacetate * This research was supported by industry gifts of pesticide products and research funding and by the National Institute of Food and Agriculture,
Plants interact with a variety of other community members that have the potential to indirectly i... more Plants interact with a variety of other community members that have the potential to indirectly influence each other through a shared host plant. Arbuscular mycorrhizal fungi (AMF) are generally considered plant mutualists because of their generally positive effects on plant nutrient status and growth. AMF may also have important indirect effects on plants by altering interactions with other community members. By influencing plant traits, AMF can modify aboveground interactions with both mutualists, such as pollinators, and antagonists, such as herbivores. Because herbivory and pollination can dramatically influence plant fitness, comprehensive assessment of plant-AMF interactions should include these indirect effects. To determine how AMF affect plant-insect interactions, we grew Cucumis sativus (Cucurbitaceae) under five AMF inoculum treatments and control. We measured plant growth, floral production, flower size, and foliar nutrient content of half the plants, and transferred the other half to a field setting to measure pollinator and herbivore preference of wild insects. Mycorrhizal treatment had no effect on plant biomass or floral traits but significantly affected leaf nutrients, pollinator behavior, and herbivore attack. Although total pollinator visitation did not vary with AMF treatment, pollinators exhibited taxon-specific responses, with honey bees, bumble bees, and Lepidoptera all responding differently to AMF treatments. Flower number and size were unaffected by treatments, suggesting that differences in pollinator preference were driven by other floral traits. Mycorrhizae influenced leaf K and Na, but these differences in leaf nutrients did not correspond to variation in herbivore attack. Overall, we found that AMF indirectly influence both antagonistic and mutualistic insects, but impacts depend on the identity of both the fungal partner and the interacting insect, underscoring the context-dependency of plant-AMF interactions.
HortTechnology
Corn oil and Bacillus thuringiensis ssp. kurstaki (Bt) applied directly into the silk channel of ... more Corn oil and Bacillus thuringiensis ssp. kurstaki (Bt) applied directly into the silk channel of a corn ear has been shown to be an effective pesticide against corn earworm, Helicoverpa zea (CEW), and european corn borer, Ostrinia nubilalis (ECB). Field studies were conducted in 2000 and 2001 to determine the influence of application timing on ear quality at harvest. Two blocks of corn were planted during each year to observe treatment effects under varying populations of the two insect species. The treatment consisted of 0.5 mL (0.017 floz) of food grade corn oil containing a suspension of Bt at 0.08 g (0.003 oz) a.i. per ear applied directly into the silk channel at the husk opening. One treatment application was made on each silk day 3 through 11 from first silk; silk day 1 was the first day that 50% or more of ears had 2.5 cm (1 inch) of silk protruding from the husk. One treatment did not receive the oil + Bt suspension. All ears were harvested at milk stage, on silk day 25. Th...
HortTechnology
High demand for local produce year-round has led growers in the northeastern United States to exp... more High demand for local produce year-round has led growers in the northeastern United States to experiment with fall planting of bulbing onion (Allium cepa) for spring harvest. Over two seasons, we evaluated survival, bolting, and bulbing of several cultivars of fall-planted onion in two sites in New Hampshire. Plants were seeded in August and September, and transplanted in September and October into raised beds covered with black plastic mulch. Low tunnels covered with 1.25-oz/yard2 rowcover and one layer of 6-mil-thick clear polyethylene were installed over the plants in late fall. Harvest dates ranged from 19 Apr. to 6 June in 2012, and from 22 May to 2 July in 2013. All onion cultivars showed high percentages of survival (65% to 100%). Cultivar, planting date, and the interaction between the two had a significant effect on the percentage of bolting and bulb diameter at harvest. In general, those planted later exhibited lower percentages of bolting and slightly smaller bulbs at har...
Arthropod Management Tests
Sweet corn was planted 2 May in blocks of 4 rows by 25 feet. Each treatment was repeated 4 times ... more Sweet corn was planted 2 May in blocks of 4 rows by 25 feet. Each treatment was repeated 4 times in a RCB design. Blocks were separated by 15 feet. Insecticides were applied on 5, 11, and 18 Jul, beginning before tassels emerged. Biweekly treatments were also sprayed on 9, 16, and 22 Jul. ECB flights were monitored with two nylon Heliothis traps baited with a Trece’ pheromone lure (New York or Iowa strain). The CEW flight was monitored with a Heliothis trap with a Hereon Helicoverpa zea lure. Sprays were applied at 75 psi with a four row drop nozzle sprayer pulled (5 nozzles per row) behind a tractor. A hand held applicator delivered 0.5 ml per ear of a 1 ;20 mixture of Dipel ES and food-grade corn oil directly to the silks on 16 Jul. Plots were harvested on 29 Jul. Fifty ears per plot were rated for damage, and for presence of CEW and ECB. Two ratings are reported; Undamaged ears = no feeding on ear; undamaged kernels = no feeding on filled kernels, may have feeding on unfilled tip.
HortTechnology
Field studies were conducted in 2000 and 2001 to rate the efficacy and longevity of four pesticid... more Field studies were conducted in 2000 and 2001 to rate the efficacy and longevity of four pesticide treatments against corn earworm (Helicoverpa zea) larvae (CEW) in sweet corn (Zea mays). The four treatments used were 1) corn oil, 2) Bacillus thuringiensis ssp. kurstaki (Bt), 3) oil + Bt, and 4) an untreated plot. All treatments were applied on silk day 5. Silk day 1 was the first day that more than 50% of the ears had 2.5 cm (1 inch) or more silks emerging from the husk using a hand-held pump applicator. Two first-instar CEW larvae were placed directly into silk channel of selected ears on 6 different days (days 3, 6, 9, 12, 15, and 18 after first silk). The same six ears were then harvested 4 days later. Untreated ears had more live CEW and higher levels of feeding damage than the other three treatments ears for all harvest days in both years. The number of CEW found per ear was lower when Bt was included in the treatment. The use of corn oil gave the lowest damage ratings on almo...
Environmental Entomology
Feeding responses that influence the effectiveness of a polyphagous endemic coccinellid, Coleomeg... more Feeding responses that influence the effectiveness of a polyphagous endemic coccinellid, Coleomegilla maculata (DeGeer), for biological control of Colorado potato beetle, Leptinotarsa decemlineata (Say), in potato were examined in the laboratory. Consumption rate, functional response, prey preference, and the effect of alternate prey were studied for C. maculata adult females feeding upon eggs of Colorado potato beetle; Myzus persicae (Sulzer) and corn pollen were alternate food sources. C. maculata females continuously supplied with eggs attacked an average of 20.8 eggs per 48 h, and introduction of M. persicae significantly reduced but did not eliminate egg feeding. Females starved for 24 h showed a Type II functional response to egg density when offered 10-70 eggs per 24 h in small cages at 26 ± 2°C. Data fit well to the Holling disk equation, which predicted maximum egg consumption of 31.5 eggs per 24 h. The functional response curve showed suppression of egg feeding at high egg densities when aphids were present as alternate prey, but no effect was evident at low egg densities. There was no change in functional response with corn pollen as the alternate food. When Colorado potato beetle eggs and aphids were available in equal numbers, females did not prefer either prey at low prey densities, but they preferred aphids over eggs at high densities. Eggs were an adequate (but not optimal) diet for larval development and adult oviposition relative to M. persicae or corn pollen. Some implications for ecology and effectiveness of C. maculata for control of Colorado potato beetle in potato are discussed.
Http Dx Doi Org 10 1603 029 102 0331, May 28, 2009
Striped cucumber beetle, Acalymma vittatum F., is the primary insect pest of cucurbit crops in th... more Striped cucumber beetle, Acalymma vittatum F., is the primary insect pest of cucurbit crops in the northeastern United States. Adult beetles colonize squash crops from field borders, causing feeding damage at the seedling stage and transmitting bacterial wilt Erwinia tracheiphila Hauben et al. 1999. Conventional control methods rely on insecticide applications to the entire field, but surrounding main crops with a more attractive perimeter could reduce reliance on insecticides. A. cittatum shows a marked preference for Blue Hubbard squash (Cucurbita maxima Duchesne) over butternut squash (C. moschata Poir). Given this preference, Blue Hubbard squash has the potential to be an effective perimeter trap crop. We evaluated this system in commercial butternut fields in 2003 and 2004, comparing fields using perimeter trap cropping with Blue Hubbard to conventionally managed fields. In 2003, we used a foliar insecticide to control beetles in the trap crop borders, and in 2004, we compared systemic and foliar insecticide treatments for the trap crop borders. We found that using a trap crop system reduced or eliminated the need to spray the main crop area, reducing insecticide use by up to 94% compared with conventional control methods, with no increase in herbivory or beetle numbers. We surveyed the growers who participated in these experiments and found a high level of satisfaction with the effectiveness and simplicity of the system. These results suggest that this method of pest control is both effective and simple enough in its implementation to have high potential for adoption among growers.
Arthropod Management Tests, 2015
Environmental Entomology, 1991
Mortality to the egg stage of Colorado potato beetle, Leptinotarsa decemlineata(Say), from endemi... more Mortality to the egg stage of Colorado potato beetle, Leptinotarsa decemlineata(Say), from endemic predators was assessed in unsprayed plots within commercial potato fields in western Massacusetts in 1986 and 1987. Direct measurement of recruitment into the egg stage and of lossesto predation gave estimates of total stage-specific mortality for each generation of Colorado potato beetle and daily mortality rates. Abundance of endemic egg predators was measured through direct observation and trapping. Coleomegilla maculata (DeGeer), a coccinellid, was the most abundant predator and the only one consistently present whenever Colorado potato beetle eggs were in the field. Total mortality to eggs from predation was 39.9% in the second generation of 1986 and 37.8% and 58.1% in the first and second generations of 1987, respectively. Daily mortality rate did not change significantly during large fluctuations in prey density. Results suggest that C. maculata can contribute to the control of both early and late generations of Colorado potato beetle and efforts to conserve this natural enemy will help reduc;:ethe need for chemical control.
Journal of Economic Entomology, Oct 1, 2004
W hen customers flock to markets in search of sweet corn, they want it to be of the highest quali... more W hen customers flock to markets in search of sweet corn, they want it to be of the highest quality--sweet, fresh and worm-free. Yet, in ecological or organic production of sweet corn, achieving worm-free corn is one of
Plant Disease, 1997
To assess the accuracy of remote, real-time mathematical simulations of wetness duration and air ... more To assess the accuracy of remote, real-time mathematical simulations of wetness duration and air temperature, hourly measurements of wetness duration and air temperature at 18 sites in the United States and Canada from May to September 1995 were compared with simulations for these sites provided by SkyBit, Inc. SkyBit simulations of mean, maximum, and minimum daily air temperatures varied from on-site measurements by less than 0.7°C but underestimated the duration of wet periods by an average of 3.4 h/day. At five of six stations tested, SkyBit underestimates of wetness duration were significantly (P < 0.01) larger on days when no rain was measured than on rainy days, indicating that simulations of dew-period duration were much less accurate than simulations of rain-period duration. The vast majority of hours SkyBit misclassified as dry occurred either when entire wet periods were missed (59.3%) or when the onset of a wet period was detected late (28.4%). The results suggest that...
Three Organic Materials Review Institute (OMRI) listed foliar treatments for control of striped c... more Three Organic Materials Review Institute (OMRI) listed foliar treatments for control of striped cucumber beetle in cucumbers were compared at the University of Massachusetts Crops Research and Education Center in South Deerfield, MA. Each material was tested alone and in combination with the other materials. Treatments included spinosad (Entrust 80W), pyrethin (PyGanic EC 5.0), and kaolin clay (Surround WP). Control plots were treated with water. Untreated seeds of 'Marketmore' pickling cucumber were planted in a heated greenhouse on 29 Apr 2009 and transplanted into the field on 27 May using a RCB design with 8 treatments and 4 replicates. Each treatment plot consisted of a 1.22m bed of two rows, 0.46m apart and 4.57m long, separated from other plots by 1.83m. Beds were covered in black plastic with one run of drip irrigation centered between the rows. Treatments were applied on 1, 8, and 15 Jun, using a CO2 R&D backpack sprayer with a flat fan nozzle delivering 19.2 gpa wa...
In 2002 a long-term cucurbit crop systems pest and crop management evaluation was continued at NY... more In 2002 a long-term cucurbit crop systems pest and crop management evaluation was continued at NYSAES Geneva. This project is a continuation of a sweet corn systems project conducted 1995-1999. Systems are located in the same fields as the previous sweet corn evaluation meaning that land has now been managed under the particular systems for 8 years. A team of vegetable experts evaluated four systems for producing cucurbit crops including Conventional, IPM Present, IPM Future, and Organic. Commercial scale plots of cucumbers, melons, zucchini, and pumpkins were grown under these systems and compared on the basis of economic, environmental, and pest control efficacy factors. In addition, demonstrations of the systems were conducted on growers' farms in eastern New York, Ohio, and Massachusetts
Arthropod Management Tests, 2015
, white, savoy) j Brassica oleracea var. capitata cabbage root maggot | Delia radicum crucifer fl... more , white, savoy) j Brassica oleracea var. capitata cabbage root maggot | Delia radicum crucifer flea beetle | Phyllotreta cruciferae 4-(2,2-difluoro-1,3-benzodioxol-4-yl)-1H-pyrrole-3-carbonitrile; methyl N-(2,6-dimethylphenyl)-N-(methoxyacetyl)-D-alaninate; methyl (aE)-2-[[6-(2-cyanophenoxy)-4-pyrimidinyl]oxy]-a-(methoxymethylene)benzeneacetate þ 3-[(2-chloro-5-thiazolyl)methyl]tetrahydro-5-methyl-N-nitro-4H-1,3,5-oxadiazin-4-imine; 4-(2,2-difluoro-1,3-benzodioxol-4-yl)-1H-pyrrole-3-carbonitrile; methyl N-(2,6-dimethylphenyl)-N-(methoxyacetyl)-D-alaninate; methyl (aE)-2-[[6-(2-cyanophenoxy)-4pyrimidinyl]oxy]-a-(methoxymethylene)benzeneacetate þ 3-[(2-chloro-5-thiazolyl)methyl]tetrahydro-5-methyl-N-nitro-4H-1,3,5-oxadiazin-4-imine; (2E)-1-[(6-chloro-3-pyridinyl)methyl]-N-nitro-2-imidazolidinimine; 4-(2,2-difluoro-1,3-benzodioxol-4-yl)-1H-pyrrole-3-carbonitrile; methyl N-(2,6-dimethylphenyl)-N-(methoxyacetyl)-D-alaninate; methyl (aE)-2-[[6-(2-cyanophenoxy)-4-pyrimidinyl]oxy]-a-(methoxymethylene)benzeneacetate * This research was supported by industry gifts of pesticide products and research funding and by the National Institute of Food and Agriculture,
Plants interact with a variety of other community members that have the potential to indirectly i... more Plants interact with a variety of other community members that have the potential to indirectly influence each other through a shared host plant. Arbuscular mycorrhizal fungi (AMF) are generally considered plant mutualists because of their generally positive effects on plant nutrient status and growth. AMF may also have important indirect effects on plants by altering interactions with other community members. By influencing plant traits, AMF can modify aboveground interactions with both mutualists, such as pollinators, and antagonists, such as herbivores. Because herbivory and pollination can dramatically influence plant fitness, comprehensive assessment of plant-AMF interactions should include these indirect effects. To determine how AMF affect plant-insect interactions, we grew Cucumis sativus (Cucurbitaceae) under five AMF inoculum treatments and control. We measured plant growth, floral production, flower size, and foliar nutrient content of half the plants, and transferred the other half to a field setting to measure pollinator and herbivore preference of wild insects. Mycorrhizal treatment had no effect on plant biomass or floral traits but significantly affected leaf nutrients, pollinator behavior, and herbivore attack. Although total pollinator visitation did not vary with AMF treatment, pollinators exhibited taxon-specific responses, with honey bees, bumble bees, and Lepidoptera all responding differently to AMF treatments. Flower number and size were unaffected by treatments, suggesting that differences in pollinator preference were driven by other floral traits. Mycorrhizae influenced leaf K and Na, but these differences in leaf nutrients did not correspond to variation in herbivore attack. Overall, we found that AMF indirectly influence both antagonistic and mutualistic insects, but impacts depend on the identity of both the fungal partner and the interacting insect, underscoring the context-dependency of plant-AMF interactions.
HortTechnology
Corn oil and Bacillus thuringiensis ssp. kurstaki (Bt) applied directly into the silk channel of ... more Corn oil and Bacillus thuringiensis ssp. kurstaki (Bt) applied directly into the silk channel of a corn ear has been shown to be an effective pesticide against corn earworm, Helicoverpa zea (CEW), and european corn borer, Ostrinia nubilalis (ECB). Field studies were conducted in 2000 and 2001 to determine the influence of application timing on ear quality at harvest. Two blocks of corn were planted during each year to observe treatment effects under varying populations of the two insect species. The treatment consisted of 0.5 mL (0.017 floz) of food grade corn oil containing a suspension of Bt at 0.08 g (0.003 oz) a.i. per ear applied directly into the silk channel at the husk opening. One treatment application was made on each silk day 3 through 11 from first silk; silk day 1 was the first day that 50% or more of ears had 2.5 cm (1 inch) of silk protruding from the husk. One treatment did not receive the oil + Bt suspension. All ears were harvested at milk stage, on silk day 25. Th...
HortTechnology
High demand for local produce year-round has led growers in the northeastern United States to exp... more High demand for local produce year-round has led growers in the northeastern United States to experiment with fall planting of bulbing onion (Allium cepa) for spring harvest. Over two seasons, we evaluated survival, bolting, and bulbing of several cultivars of fall-planted onion in two sites in New Hampshire. Plants were seeded in August and September, and transplanted in September and October into raised beds covered with black plastic mulch. Low tunnels covered with 1.25-oz/yard2 rowcover and one layer of 6-mil-thick clear polyethylene were installed over the plants in late fall. Harvest dates ranged from 19 Apr. to 6 June in 2012, and from 22 May to 2 July in 2013. All onion cultivars showed high percentages of survival (65% to 100%). Cultivar, planting date, and the interaction between the two had a significant effect on the percentage of bolting and bulb diameter at harvest. In general, those planted later exhibited lower percentages of bolting and slightly smaller bulbs at har...
Arthropod Management Tests
Sweet corn was planted 2 May in blocks of 4 rows by 25 feet. Each treatment was repeated 4 times ... more Sweet corn was planted 2 May in blocks of 4 rows by 25 feet. Each treatment was repeated 4 times in a RCB design. Blocks were separated by 15 feet. Insecticides were applied on 5, 11, and 18 Jul, beginning before tassels emerged. Biweekly treatments were also sprayed on 9, 16, and 22 Jul. ECB flights were monitored with two nylon Heliothis traps baited with a Trece’ pheromone lure (New York or Iowa strain). The CEW flight was monitored with a Heliothis trap with a Hereon Helicoverpa zea lure. Sprays were applied at 75 psi with a four row drop nozzle sprayer pulled (5 nozzles per row) behind a tractor. A hand held applicator delivered 0.5 ml per ear of a 1 ;20 mixture of Dipel ES and food-grade corn oil directly to the silks on 16 Jul. Plots were harvested on 29 Jul. Fifty ears per plot were rated for damage, and for presence of CEW and ECB. Two ratings are reported; Undamaged ears = no feeding on ear; undamaged kernels = no feeding on filled kernels, may have feeding on unfilled tip.
HortTechnology
Field studies were conducted in 2000 and 2001 to rate the efficacy and longevity of four pesticid... more Field studies were conducted in 2000 and 2001 to rate the efficacy and longevity of four pesticide treatments against corn earworm (Helicoverpa zea) larvae (CEW) in sweet corn (Zea mays). The four treatments used were 1) corn oil, 2) Bacillus thuringiensis ssp. kurstaki (Bt), 3) oil + Bt, and 4) an untreated plot. All treatments were applied on silk day 5. Silk day 1 was the first day that more than 50% of the ears had 2.5 cm (1 inch) or more silks emerging from the husk using a hand-held pump applicator. Two first-instar CEW larvae were placed directly into silk channel of selected ears on 6 different days (days 3, 6, 9, 12, 15, and 18 after first silk). The same six ears were then harvested 4 days later. Untreated ears had more live CEW and higher levels of feeding damage than the other three treatments ears for all harvest days in both years. The number of CEW found per ear was lower when Bt was included in the treatment. The use of corn oil gave the lowest damage ratings on almo...
Environmental Entomology
Feeding responses that influence the effectiveness of a polyphagous endemic coccinellid, Coleomeg... more Feeding responses that influence the effectiveness of a polyphagous endemic coccinellid, Coleomegilla maculata (DeGeer), for biological control of Colorado potato beetle, Leptinotarsa decemlineata (Say), in potato were examined in the laboratory. Consumption rate, functional response, prey preference, and the effect of alternate prey were studied for C. maculata adult females feeding upon eggs of Colorado potato beetle; Myzus persicae (Sulzer) and corn pollen were alternate food sources. C. maculata females continuously supplied with eggs attacked an average of 20.8 eggs per 48 h, and introduction of M. persicae significantly reduced but did not eliminate egg feeding. Females starved for 24 h showed a Type II functional response to egg density when offered 10-70 eggs per 24 h in small cages at 26 ± 2°C. Data fit well to the Holling disk equation, which predicted maximum egg consumption of 31.5 eggs per 24 h. The functional response curve showed suppression of egg feeding at high egg densities when aphids were present as alternate prey, but no effect was evident at low egg densities. There was no change in functional response with corn pollen as the alternate food. When Colorado potato beetle eggs and aphids were available in equal numbers, females did not prefer either prey at low prey densities, but they preferred aphids over eggs at high densities. Eggs were an adequate (but not optimal) diet for larval development and adult oviposition relative to M. persicae or corn pollen. Some implications for ecology and effectiveness of C. maculata for control of Colorado potato beetle in potato are discussed.
Http Dx Doi Org 10 1603 029 102 0331, May 28, 2009
Striped cucumber beetle, Acalymma vittatum F., is the primary insect pest of cucurbit crops in th... more Striped cucumber beetle, Acalymma vittatum F., is the primary insect pest of cucurbit crops in the northeastern United States. Adult beetles colonize squash crops from field borders, causing feeding damage at the seedling stage and transmitting bacterial wilt Erwinia tracheiphila Hauben et al. 1999. Conventional control methods rely on insecticide applications to the entire field, but surrounding main crops with a more attractive perimeter could reduce reliance on insecticides. A. cittatum shows a marked preference for Blue Hubbard squash (Cucurbita maxima Duchesne) over butternut squash (C. moschata Poir). Given this preference, Blue Hubbard squash has the potential to be an effective perimeter trap crop. We evaluated this system in commercial butternut fields in 2003 and 2004, comparing fields using perimeter trap cropping with Blue Hubbard to conventionally managed fields. In 2003, we used a foliar insecticide to control beetles in the trap crop borders, and in 2004, we compared systemic and foliar insecticide treatments for the trap crop borders. We found that using a trap crop system reduced or eliminated the need to spray the main crop area, reducing insecticide use by up to 94% compared with conventional control methods, with no increase in herbivory or beetle numbers. We surveyed the growers who participated in these experiments and found a high level of satisfaction with the effectiveness and simplicity of the system. These results suggest that this method of pest control is both effective and simple enough in its implementation to have high potential for adoption among growers.
Arthropod Management Tests, 2015
Environmental Entomology, 1991
Mortality to the egg stage of Colorado potato beetle, Leptinotarsa decemlineata(Say), from endemi... more Mortality to the egg stage of Colorado potato beetle, Leptinotarsa decemlineata(Say), from endemic predators was assessed in unsprayed plots within commercial potato fields in western Massacusetts in 1986 and 1987. Direct measurement of recruitment into the egg stage and of lossesto predation gave estimates of total stage-specific mortality for each generation of Colorado potato beetle and daily mortality rates. Abundance of endemic egg predators was measured through direct observation and trapping. Coleomegilla maculata (DeGeer), a coccinellid, was the most abundant predator and the only one consistently present whenever Colorado potato beetle eggs were in the field. Total mortality to eggs from predation was 39.9% in the second generation of 1986 and 37.8% and 58.1% in the first and second generations of 1987, respectively. Daily mortality rate did not change significantly during large fluctuations in prey density. Results suggest that C. maculata can contribute to the control of both early and late generations of Colorado potato beetle and efforts to conserve this natural enemy will help reduc;:ethe need for chemical control.