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Featured researches published by Dean Polk.


Journal of Economic Entomology | 2002

Development and Implementation of a Reduced Risk Peach Arthropod Management Program in New Jersey

Atanas Atanassov; Peter W. Shearer; George C. Hamilton; Dean Polk

Abstract We implemented a 2-yr program to reduce organophosphorus and carbamate insecticide use and mitigate their associated risks as they relate to peach production in New Jersey and elsewhere. The main thrust integrated mating disruption with ground cover management practices to reduce oriental fruit moth, Grapholita molesta (Busck) (Lepidoptera: Tortricidae), and tarnished plant bug, Lygus lineolaris (Palisot de Beauvois) (Heteroptera: Miridae), abundance and damage. This Reduced Risk Peach Arthropod Management Program was compared with adjacent conventionally managed peach orchards. In 1999, we found 2.3 times fewer L. lineolaris and stink bugs (Euschistus servus (Say), E. tristigmus (Say), Acrosternum hilare (Say) (Heteroptera: Pentatomidae) and 2.0 times less heteropteran damaged peaches in reduced-risk orchards when compared with conventionally managed orchards. In 2000, we observed 4.9 times fewer heteropteran insects in reduced-risk orchards but damage levels were not significantly different between the two programs. In both years, G. molesta mating disruption gave at least 4 mo of noninsecticidal control of this major pest. The reduced-risk program provided a level of pest control that was equal to or better than conventional peach pest management programs while using fewer organophosporus and carbamate insecticides.


Environmental Entomology | 2015

Attraction of the invasive halyomorpha halys (Hemiptera: Pentatomidae) to traps baited with semiochemical stimuli across the United States

Tracy C. Leskey; Arthur M. Agnello; J. Christopher Bergh; Galen P. Dively; George C. Hamilton; Peter Jentsch; Ashot Khrimian; Grzegorz Krawczyk; Thomas P. Kuhar; Doo Hyung Lee; William R. Morrison; Dean Polk; Cesar Rodriguez-Saona; Peter W. Shearer; Brent D. Short; Paula M. Shrewsbury; James F. Walgenbach; Donald C. Weber; Celeste Welty; Joanne Whalen; Nik G. Wiman; Faruque U. Zaman

ABSTRACT A recent identification of the two-component aggregation pheromone of the invasive stink bug species, Halyomorpha halys (Stål), in association with a synergist, has greatly improved the ability to accurately monitor the seasonal abundance and distribution of this destructive pest. We evaluated the attraction of H. halys to black pyramid traps baited with lures containing the pheromone alone, the synergist methyl (2E,4E,6Z)-decatrienoate (MDT) alone, and the two lures in combination. Traps were deployed around areas of agricultural production including fruit orchards, vegetables, ornamentals, or row crops in Delaware, Maryland, North Carolina, New Jersey, New York, Ohio, Oregon, Pennsylvania, Virginia, and West Virginia from mid-April to mid-October, 2012 and 2013. We confirmed that H. halys adults and nymphs are attracted to the aggregation pheromone season long, but that attraction is significantly increased with the addition of the synergist MDT. H. halys adults were detected in April with peak captures of overwintering adults in mid- to late May. The largest adult captures were late in the summer, typically in early September. Nymphal captures began in late May and continued season long. Total captures declined rapidly in autumn and ceased by mid-October. Captures were greatest at locations in the Eastern Inland region, followed by those in the Eastern Coastal Plain and Pacific Northwest. Importantly, regardless of location in the United States, all mobile life stages of H. halys consistently responded to the combination of H. halys aggregation pheromone and the synergist throughout the entire season, suggesting that these stimuli will be useful tools to monitor for H. halys in managed systems.


Pest Management Science | 2015

IPM-CPR for peaches: incorporating behaviorally-based methods to manage Halyomorpha halys and key pests in peach.

Brett R. Blaauw; Dean Polk; Anne L. Nielsen

BACKGROUND The invasive brown marmorated stink bug, Halyomorpha halys (Stål) (Hemiptera: Pentatomidae), has emerged as a key pest in mid-Atlantic peach production. Current management of H. halys has disrupted IPM programs by relying exclusively on frequent, repeated, season-long insecticide applications. We developed a behaviorally-based tactic termed IPM-CPR (Crop Perimeter Restructuring) that utilizes border sprays for H. halys, groundcover management for Lygus lineolaris (Palisot de Beauvois) (Hemiptera: Miridae) and mating disruption for Grapholita molesta (Busck) (Lepidoptera: Tortricidae). RESULTS IPM-CPR reduced insecticide usage by 25-61%. Generally there was less, and at times significantly less, catfacing injury (attributable to H. halys) in peaches in the IPM-CPR blocks relative to the standard, and minimal differences in injury due to G. molesta or L. lineolaris. These results suggest that perimeter applications of insecticides exploit the border-arrestment behavior of H. halys by controlling them at the orchard edge, reducing damage throughout the block. CONCLUSION IPM-CPR significantly reduces the area managed by growers for control of H. halys, while simultaneously managing key pests at levels equal to current grower standard practices. This approach brings IPM tactics back into the orchard system after disruption by the invasive H. halys and potentially supports beneficial insects.


Journal of Economic Entomology | 2014

Spatial Distribution of Brown Marmorated Stink Bug (Hemiptera: Pentatomidae) Injury at Harvest in Mid-Atlantic Apple Orchards

Shimat V. Joseph; Jonathan Stallings; Tracy C. Leskey; Greg Krawczyk; Dean Polk; Bryan Butler; J. Christopher Bergh

ABSTRACT Brown marmorated stink bug, Halyomorpha halys (Stål), injury to late-season apple cultivars was measured at harvest in 2011 and 2012 in commercial orchards in four mid-Atlantic states. In each orchard block, a border zone (adjacent to woods), an interior zone (near orchard center), and an intermediate zone (between border and interior zones) comprised 1–3 tree rows per zone, depending on block size. Just before commercial harvest, 10 fruit were sampled from the upper, middle, and lower third of the canopy from five trees in each zone. After 3–5 wk in cold storage, fruit were examined for external and internal injury, and severity of internal injury (number of injury sites per fruit) from H. halys. A zero-inflated negative binomial model accounted for significant variation among the orchards and showed that apples from the upper canopy of border zone trees had the highest probability of experiencing external and internal injury. A minor interaction was detected among the orchards and zones for injury prevalence and severity, but there was no evidence of an orchard showing less expected injury in the border zone compared with other zones. Adjusting for orchard-to-orchard variation, differences in injury distributions among the zones and canopies were primarily due to injury prevalence rather than expected injury severity. The implications of these results to scouting and managing H. halys in eastern apple orchards are discussed.


Journal of Economic Entomology | 2009

Optimization of Pheromone Deployment for Effective Mating Disruption of Oriental Beetle (Coleoptera: Scarabaeidae) in Commercial Blueberries

Cesar Rodriguez-Saona; Dean Polk; James D. Barry

ABSTRACT Cost is a potential limiting factor in the adoption of mating disruption to control oriental beetle, Anomala orientalis (Waterhouse) (Coleoptera: Scarabaeidae). A 3-yr study was conducted in 1-ha blueberry, Vaccinium corymbosum L, plots to test the possibility of lowering cost by reducing the number of point-source dispensers and pheromone [(Z)-7-tetradecen-2-one] concentrations, while maintaining mating disruption. Trap shutdown, as measured by the disruption index (DI), caged females, and sentinel potted-plants with tethered females were used to assess the success of mating disruption. Disrupted plots had DI values of ≥93% in all years, and a lower percentage of mated females, compared with control plots. However, DI values were ≥95% at ≥50 dispensers per ha. When 25 dispensers containing 0.05 g of active ingredient (AI) were used per hectare, the numbers of males in female cages and larvae in sentinel pots were similar to controls. Thus, dispenser density was critical for successful mating disruption of oriental beetles. Male oriental beetles approach the dispensers at all times of the day according to field observations, indicative of competitive attraction as a potential mechanism for mating disruption. However, at peak activity, greater male attraction was observed to dispensers containing 0.1 g of pheromone than 0.05 or 0.025 g, demonstrating the importance of pheromone rate. Although dispensers continued to emit pheromone for at least 7 wk in the field, emission rates dropped to levels close to 0 after 3 wk. We conclude that deployment of ≥50 dispensers/ha at ≥0.1 g (AI) per dispenser is the most effective rate for mating disruption of oriental beetle in blueberries.


Environmental Entomology | 2010

SPLAT-OrB reveals competitive attraction as a mechanism of mating disruption in oriental beetle (Coleoptera: Scarabaeidae).

Cesar Rodriguez-Saona; Dean Polk; Robert Holdcraft; Durairaj Chinnasamy; Agenor Mafra-Neto

ABSTRACT This study compared the efficacy of SPLAT-OrB, a new pheromone formulation for oriental beetle mating disruption that can be mechanically applied, with hand-applied plastic dispensers in commercial blueberry fields. Both formulations were tested at 2.5 and 5 g of the major sex pheromone component (Z)-7-tetradecen-2-one per hectare, and evaluated by measuring trap shutdown, mating success of caged females, and the number of grubs in sentinel blueberry pots baited with tethered females. All pheromone-treated plots had fewer male captures in traps and lower mating success of caged females compared with untreated plots. SPLAT-OrB, and plastic dispensers at the higher rate, also reduced the number of grubs in sentinel pots. To understand the mechanism of mating disruption in oriental beetle, males were observed approaching the pheromone sources in disrupted plots. In addition, male oriental beetle captures were quantified in plots treated with varying SPLAT-OrB dollop densities per ha. Consistent with predictions for competitive attraction, field observations revealed males approaching the pheromone source and male captures decreasing concavely with increasing dollop density. In a mark-release-recapture study, male oriental beetles responded to SPLAT-OrB dollops and plastic dispensers at least 60 m from the source. Additionally, SPLAT-OrB emitted pheromone that was attractive to male oriental beetles for >5 wk; however, emission rates and attraction dropped rapidly during the first 3–4 wk. This study demonstrates the feasibility of using SPLAT-OrB for oriental beetle mating disruption as an alternative to hand-applied plastic dispensers, and conclusively reveals that a principal mechanism is the competitive attraction of males.


Journal of Applied Entomology | 2014

Long-term evaluation of field-wide oriental beetle (Col., Scarabaeidae) mating disruption in blueberries using female-mimic pheromone lures

Cesar Rodriguez-Saona; Dean Polk; Robert Holdcraft; Albrecht M. Koppenhöfer

The oriental beetle, Anomala orientalis (Waterhouse) (Col., Scarabaeidae), is the most important root‐feeding pest of blueberries and turfgrass in New Jersey, USA. Previous studies showed that mating disruption is a feasible option for oriental beetle management; however, assessing its efficiency can be challenging, and little is known on its long‐term effects. Accordingly, we conducted studies to investigate low‐dose pheromone lures equivalent to oriental beetle females (i.e. female mimics) as easy‐to‐use indicators of mating disruption success, determine the distance at which oriental beetle males respond to female‐mimic lures and assess the long‐term (3‐year) effects of mating disruption on oriental beetle populations in entire blueberry fields. Our studies showed that rubber septa baited with 0.3 μg of the oriental beetle sex pheromone (Z)‐7‐tetradecen‐2‐one attract similar numbers of males as compared with virgin females and can thus be used as a female mimic. The range of attraction of this lure was found to be also similar to virgin females and <30 m. In blueberries, mating disruption provided 87% inhibition of oriental beetle populations (trap shutdown) over a 3‐year period. Oriental beetle male captures in disrupted fields were threefold higher along the field edges than in the field interiors, indicating movement of males from nearby areas into the pheromone‐treated fields. In addition, mating disruption reduced male attraction to female‐mimic lures by 93% in all 3 years and reduced the number of larvae in sentinel potted plants in 1 of 2 years. These results show for the first time that mating disruption provides consistent long‐term field‐wide control of oriental beetle populations and that female‐mimic pheromone lures can be used as a new tool to assess oriental beetle mating disruption success.


Pest Management Science | 2013

Lethality of reduced-risk insecticides against plum curculio (Coleoptera: Curculionidae) in blueberries, with emphasis on their curative activity

Cesar Rodriguez-Saona; John C. Wise; Dean Polk; Tracy C. Leskey; Christine Vandervoort

BACKGROUND Historically, management of plum curculio, Conotrachelus nenuphar (Herbst), in highbush blueberries has focused on post-bloom broad-spectrum insecticide applications targeting the adults. Here, the efficacy of different classes of insecticides against various stages of C. nenuphar was compared, and a prebloom treatment with the chitin synthesis inhibitor novaluron in combination with a post-bloom insecticide application was tested. RESULTS Novaluron decreased the number of oviposition scars and eggs on fruit and reduced larval emergence by >60% when applied prebloom. Post-bloom applications of the oxadiazine indoxacarb and the organophosphate phosmet, but not the neonicotinoid acetamiprid, showed significant adulticidal activity. The neonicotinoids acetamiprid and thiamethoxam and phosmet showed significant curative activity on C. nenuphar larvae when applied topically to infested fruit, whereas the pyrethroid fenpropathrin, indoxacarb and novaluron were weaker curative agents. Residue profiles showed that acetamiprid and phosmet residues had the highest levels while fenpropathrin and novaluron had the lowest levels of fruit penetration. CONCLUSIONS In blueberries, novaluron showed anti-ovipositional/ovicidal activity, indoxacarb and phosmet showed adulticidal activity, while the neonicotinoids and phosmet showed best curative (larvicidal) control on C. nenuphar. A prebloom novaluron application in combination with a post-bloom treatment with an adulticidal/larvicidal insecticide is recommended for optimal multi-life-stage management of C. nenuphar.


Journal of Economic Entomology | 2010

Seasonal Abundance, Life History, and Parasitism of Caloptilia porphyretica (Lepidoptera: Gracillariidae), a Leafminer of Highbush Blueberry

James D. Barry; Cesar Rodriguez-Saona; Dean Polk; Aijun Zhang

ABSTRACT The leafminer Caloptilia porphyretica Braun (Lepidoptera: Gracillariidae), has become a frequent pest in commercial highbush blueberries, Vaccinium corymbosum L., in New Jersey, but little is known about its seasonal abundance, life history, and parasitism rates. Monitoring programs were conducted from 2003 to 2006 on seven blueberry farms to determine the relative abundance of this leafminer by using pheromone-baited traps and by sampling vegetative and flower/fruit clusters and new shoot growth. We found at least three distinct generations per year, with populations reaching their highest peak in the second generation. Laboratory studies characterized the life history of C. porphyretica and its parasitoid Pholetesor sp. prob. salalicus (Mason). The developmental period of C. porphyretica, from egg to adult, took 927, 838, and 912 degree-days (DD) at 20, 25, and 30°C, respectively, by using a developmental threshold of 4.8°C. This was equivalent to an average of 892 DD to complete development to adult, which compared with 870 and 880 DD between the first and second, and second and third generations, respectively, by using pheromone trap data averaged from 2004 to 2006. Although C. porphyretica populations varied greatly, the number of larvae in cluster and new shoot samples was highly correlated with the number of adults in traps. Field parasitism rate was ≈29%, with the braconid Pholetesor sp. the most abundant parasitoid. Ten of the 13 parasitoid species collected belonged to the family Eulophidae. When different ages of leafminers were exposed to Pholetesor sp., we found that the parasitoid attacks 9-15-d-old instars that reside in the mines of leaves.


Archive | 2014

Integrating Research and Extension for Successful Integrated Pest Management

Cesar Rodriguez-Saona; Dean Polk; Lukasz L. Stelinski

A successful integrated pest management (IPM) program requires the integration of both research and extension. Current restrictions on pesticide use have demanded research on reduced-risk practices. For instance, in the US, the US Environmental Protection Agency Food Quality Protection Act (EPA FQPA) of 1996 imposes restrictions and tolerance reassessments on the use of broad-spectrum insecticides. Reduced-risk pest management practices include the use of softer pesticides, mating disruption technologies, development of degree-day models, geo-spatial technologies, cultural and ground cover management, and methods that conserve biological control agents. Constant threats from newly introduced pests are a major obstacle for IPM implementation because they disrupt existing practices. In addition, increased economic pressures that growers face, such as increased pesticide and labor costs and grower market competition, provide another dimension to this situation. More than ever the integration of multiple pest management tactics is needed for the development and implementation of sustainable IPM programs. The adoption of new technologies into existing IPM programs will depend on a comprehensive extension program that combines traditional forms of communication (e.g., outreach presentations, on-farm demonstrations, newsletters, factsheets, etc.) with new internet-based tools (e.g., WebPages, blogs, and webinars). Here we discuss various ways in which research and extension efforts can be coordinated to develop a successful pest management program. In particular, we provide examples based on our own experiences in peaches, blueberries, citrus, and apples.

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Cesar Rodriguez-Saona

Tamil Nadu Agricultural University

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Tracy C. Leskey

Agricultural Research Service

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