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Mark E. Whalon - One of the best experts on this subject based on the ideXlab platform.

  • Comparing the Emergence of Northern Strain Plum Curculio Larvae From Multiple Fruit Varieties
    Journal of economic entomology, 2014
    Co-Authors: R. D. Selby, Mark E. Whalon
    Abstract:

    ABSTRACT Increasing restrictions on chemical pesticide use in orchards have encouraged the use of alternative strategies to control the northern strain of the plum curculio, Conotrachelus Nenuphar (Herbst). Some of these strategies target larvae as they emerge from fruit, so existing models for larval emergence from fruit were evaluated for accuracy while examining the effect of multiple larvae and fruit type on emergence timing. Larval head width growth rate was established and used to gauge larval development. Larval emergence timing, quantified as degree—days (base 11.1°C), was recorded in tart cherries on trees, and emergence timing was recorded in multiple apple varieties both in cyclical field conditions and in constant laboratory conditions. Ovipositing females and fruit were isolated, so larvae in a fruit were all siblings. Adult emergences from pupation in soil were recorded in the laboratory and compared with existing model predictions. Model predictions did not accurately reflect the timing of ...

  • Behavioral and electroantennogram responses of plum curculio, Conotrachelus Nenuphar, to selected noxious plant extracts and insecticides
    Journal of insect science (Online), 2014
    Co-Authors: A. Gӧkçe, Lukasz L. Stelinski, D. R. Nortman, W. W. Bryan, Mark E. Whalon
    Abstract:

    Behavioral and electroantennogram responses of plum curculio, Conotrachelus Nenuphar (Herbst) (Coleoptera: Curculionidae), adults were tested for several methanolic plant extracts and organically approved insecticides. Plant extracts were evaluated for their potential as antifeedants or oviposition deterrents. These extract responses were also compared to those elicited by the non-neurotoxic, organic irritant-insecticide kaolin clay. Both sexes of plum curculio exhibited antennal response as measured by electroantennogram, which ranged from 0.2 to 1.1 mV, to plant extracts and the organic irritant/insecticide, with the greatest response to the extract of rough cocklebur, Xanthium strumarium L. (1.1 mV). No choice tests were conducted to compare feeding and oviposition by plum curculio on untreated apples or on apples treated with one of the extracts or the insecticide. The insecticide pyrethrum and extracts of X. strumarium and greater burdock, Arctium lappa L., significantly reduced feeding. Also, pyrethrum, A. lappa, Humulus lupulus L. (common hop), X. strumarium, and Verbascum songaricum Schrenk extracts completely inhibited egg deposition. In no-choice assays, the effects of kaolin clay with incorporated plant extracts on plum curculio feeding and oviposition were monitored as complementary tests. A. lappa—kaolin, H. lupulus—kaolin, and X. strumarium—kaolin mixtures significantly reduced the feeding of plum curculio compared to the control or kaolin clay alone. Each of the plant extract—kaolin mixtures evaluated, with the exception of Bifora radians Bieberstein (wild bishop), completely inhibited plum curculio oviposition as compared to controls.

  • novel life stage targets against plum curculio Conotrachelus Nenuphar herbst in apple integrated pest management
    Pest Management Science, 2007
    Co-Authors: John C. Wise, Eric J. Hoffmann, Ki Duk Kim, Christine Vandervoort, Ayhan Gokce, Mark E. Whalon
    Abstract:

    In this study the authors employed the plant-insect-chemistry (PIC) triad to investigate two novel life stage targets against the plum curculio (PC), Conotrachelus Nenuphar (Herbst), in apple integrated pest management (IPM). Laboratory treated apple bioassays were used to determine if the insect growth regulator (IGR) insecticides novaluron and tebufenozide have physiological effects on PC larvae following adult exposure. Curative activity bioassays were conducted for IGR, neonicotinoid, oxidiazine and organophosphate insecticides on PC larvae post-infestation, and fruit penetration profiles of insecticides were developed. The results revealed that novaluron exhibits activity on PC larvae via vertical transmission following exposure of mated females to treated substrate. Surface treatments of azinphos-methyl, thiacloprid and thiamethoxam to preinfested fruit resulted in significant reductions in larval emergence. For all compounds, 50% or more of the total recovered active ingredient was from apple skin, and for azinphos-methyl, indoxacarb and thiamethoxam it was greater than 80%. For azinphos-methyl, novaluron, methoxyfenozide and thiacloprid, however, active ingredient was recovered from every section of the apple, from skin to core. Implications for twenty-first century IPM are discussed.

  • Pyriproxyfen activates reproduction in prediapause northern strain plum curculio (Conotrachelus Nenuphar Herbst)
    Pest management science, 2007
    Co-Authors: Eric J. Hoffmann, Joshua Vanderjagt, Mark E. Whalon
    Abstract:

    Field-collected, prediapause northern strain plum curculio, Conotrachelus Nenuphar (Herbst), adults were treated with the juvenile hormone analogue pyriproxyfen to assess effects on reproductive development. Adults of this pest have an obligate winter reproductive diapause and do not reach reproductive maturity until after spring emergence. Topical (1.0 µL) doses of 10, 1.0 and 0.1 µg µL−1 pyriproxyfen induced oocyte development and reproductive maturation in all treated females as assessed by dissection. There was no increased mortality in treated beetles, and control insects showed no reproductive maturation. Treatment of prediapause males and females with 1.0 µg µL−1 of topical pyriproxyfen or exposure to residues on fruit induced successful egg laying and F1 emergence; F1 pupation success in topical treatments and residue exposure was 47 and 59% respectively. Filial adults require re-exposure to initiate reproductive development. Treatment protocols with pyriproxyfen will allow researchers to culture the northern strain, instead of relying exclusively on the non-diapausing southern strain. Copyright © 2007 Society of Chemical Industry

  • Reproductive Development of Northern and Southern Strains of Plum Curculio (Coleoptera: Curculionidae)
    Journal of economic entomology, 2004
    Co-Authors: Eric J. Hoffmann, Andrea B. Coombs, Mark E. Whalon
    Abstract:

    Abstract Laboratory-reared southern and field-collected northern strains of plum curculio, Conotrachelus Nenuphar (Herbst), were sampled to examine the relationship between degree-day (DD) accumulation and female reproductive development, as measured by mating status, oocyte size, and number of oocytes. The overall goal was to generate an objective degree-day model for predicting damage potential that could be applied to various host commodities rather than relying on separate biofix models for each crop. Adult beetles were dissected to measure mating status, maximum oocyte size, and number of oocytes. Southern strain beetles reared at 25°C initiated mating 9 d after eclosion and did not require mating to induce oocyte development. By 20 d posteclosion, unmated females had significantly higher egg loads compared with mated females of the same age. Logistic regression analysis suggests that southern and northern strain beetles had a stable maximum oocyte length of 62 and 72 μm, respectively. Northern strai...

Tracy C Leskey - One of the best experts on this subject based on the ideXlab platform.

  • A Review of the Biology, Ecology, and Management of Plum Curculio (Coleoptera: Curculionidae)
    Journal of Integrated Pest Management, 2020
    Co-Authors: Timothy P Lampasona, Tracy C Leskey, Cesar Rodriguez-saona, Anne L Nielsen
    Abstract:

    Abstract The plum curculio, Conotrachelus Nenuphar Herbst (Coleoptera: Curculionidae), is an insect native to the Americas that is a serious pest of stone and pome fruits in the United States and Canada. Failure to effectively manage this insect may result in up to 85% damaged fruit at harvest, as well as early season fruit abortion. Conotrachelus Nenuphar is oligophagous, feeding and ovipositing on many Rosaceous plants, including apple, peach, plum, cherry, quince, and pear. Additionally, C. Nenuphar in limited geographic ranges utilizes alternate hosts such as highbush blueberry (Ericaceae) and Muscadine grape (Vitaceae). Despite its long history as a pest, integrated pest management (IPM) lags behind similarly damaging native fruit pests. Although significant progress has been made on the identification of attractive lures for monitoring C. Nenuphar adults, development of behaviorally based management strategies, and biological control with entomopathogenic nematodes, growers continue to rely heavily on top-down chemical inputs to manage this pest. Most of the research to date comes from studies done in apples where alternative management practices for C. Nenuphar have, to some extent, been adopted; however, less IPM-based information is available for other susceptible crops. In this review, we summarize the history, biology, ecology, behavior, and control of C. Nenuphar and future directions for IPM research.

  • olfactometer responses of plum curculio Conotrachelus Nenuphar herbst coleoptera curculionidae to host plant volatiles synthetic grandisoic acid and live conspecifics
    Journal of Insect Behavior, 2017
    Co-Authors: Virginia Hock, Tracy C Leskey, Gérald Chouinard, Daniel Cormier, Eric Lucas, Aijun Zhang
    Abstract:

    The plum curculio Conotrachelus Nenuphar (Herbst) (Coleoptera: Curculionidae) is a major pest of pome and stone fruit, but will also attack other fruits. Males produce the aggregation pheromone grandisoic acid; emitting only the (+)-enantiomer which is attractive to both sexes of the univoltine and multivoltine strains, while the synthetic racemic mixture contains optical isomers with equal amounts of (+)- and (−)-enantiomers. Synergy between odours can increase trap captures and improve monitoring techniques, therefore tests were performed in a dual-choice olfactometer with odours attractive to plum curculios according to literature to determine 1) under what physiological conditions (mating status, age, starvation period) these odours are attractive or repulsive, 2) if the (+)-enantiomer or the odour of live males synergizes with host plant volatiles, and 3) if there is a difference in response between plum curculio strains. Females were exposed to: benzaldehyde; trans-2-hexenal; apples; extracts of: plums, apples, blueberries; grandisoic acid; and live males. Plum essence was found to be the most attractive host-plant odour for both immature and mature virgin females, and immature whole apples were attractive to starved females, while trans-2-hexenal, McIntosh apple essence, benzaldehyde along with the combination of benzaldehyde and plume essence was found to be repulsive. Starvation, age, and mated status all influence response to odours. No synergistic or additive affects were observed between any of the odour combinations tested, including the combination of both the natural and synthetic pheromone and plum essence or apples.

  • Evaluating Electrophysiological and Behavioral Responses to Volatiles for Improvement of Odor-Baited Trap Tree Management of Conotrachelus Nenuphar (Coleoptera: Curculionidae)
    Environmental entomology, 2014
    Co-Authors: Tracy C Leskey, Gérald Chouinard, Daniel Cormier, Virginia Hock, Kathleen Leahy, Daniel R. Cooley, Arthur Tuttle, Alan Eaton, Aijun Zhang
    Abstract:

    ABSTRACT Plum curculio, Conotrachelus Nenuphar (Herbst), one of the most important pests of apple in eastern and central North America, is usually managed in New England apple orchards by multiple full-block insecticide applications. Efforts to reduce insecticide inputs against plum curculio include using an “attract and kill” approach: odor-baited trap trees deployed in the perimeter row of apple orchards. The standard approach is based on baiting apple trees with two olfactory stimuli, the fruit volatile benzaldehyde and the aggregation pheromone of plum curculio, grandisoic acid. We attempted to improve attraction, aggregation, and retention of adult plum curculios within specific baited trap tree canopies within apple orchards using an additional host plant volatile found to be highly stimulating in electroantennogram studies, trans-2-hexenal. We also attempted to increase aggregation using increased release rates of grandisoic acid. We found that trans-2-hexenal did not provide increased aggregation ...

  • Establishing abiotic and biotic factors necessary for reliable male pheromone production and attraction to pheromones by female plum curculios Conotrachelus Nenuphar (Coleoptera: Curculionidae)
    Canadian Entomologist, 2014
    Co-Authors: Virginia Hock, Tracy C Leskey, Starker E. Wright, Gérald Chouinard, Daniel Cormier, Aijun Zhang, Eric Lucas, André Pichette
    Abstract:

    The plum curculio (PC), Conotrachelus Nenuphar Herbst (Coleoptera: Curculionidae), is a key pest of stone and pome fruit in North America. Though grandisoic acid (GA) was identified as a male-produced aggregation pheromone for this species, other components likely exist, as have been identified for various curculionids. To better determine these components, an understanding of the conditions necessary for optimum pheromone production and attraction is needed, this is essential for the improvement of monitoring techniques and to achieve better biological control. The goal of this study was to determine the biotic and abiotic factors influencing both the response to pheromones and pheromone production. Tests were conducted in a dual-choice still-air vertical olfactometer using live male PCs as odour sources and live females as responders, to determine which physiological factors (age, number of males, mating status) influenced female response to males. Head-space collections of GA production under various conditions (airflow rate and frequency, collection zone strata, variation of humidity, temperature, and presence of a harbourage) were also done, as were electroantennograms (EAG) using synthetic pheromone mixtures. Results revealed that for both strains, the odour of two virgin mature males elicited significantly greater and more consistent attraction from mature virgin females than other ages and numbers of males when compared with the control. Head-space collections indicate that male PC have increased production of GA under high humidity in the presence of fruit, indicating that these conditions are necessary for optimal pheromone production and collection. EAG studies revealed significant responses to GrandLures I, II, III/IV and to the positive enantiomer of GA, and the amplitude of the signal varied with concentration. Our data identify the optimal physiological state and conditions at which pheromone collections should be performed, and what physiological life stages respond to these stimuli. These results have implications for optimising monitoring tools for this serious crop pest. This species has a northern univoltine strain and a southern multivoltine strain, both of which were examined in this study.

  • Using entomopathogenic nematodes for biological control of plum curculio, Conotrachelus Nenuphar: Effects of irrigation and species in apple orchards
    Biological Control, 2013
    Co-Authors: David I. Shapiro-ilan, Starker E. Wright, Daniel R. Cooley, Arthur Tuttle, Tracy C Leskey
    Abstract:

    Abstract The plum curculio, Conotrachelus Nenuphar , is a major pest of stone and pome fruit (e.g., apples, pears, peaches, cherries, etc.). Entomopathogenic nematodes ( Steinernema spp. and Heterorhabditis spp.) are virulent to ground-dwelling stages of C. Nenuphar and may be incorporated into an integrated management strategy. Two significant questions that must be addressed prior to implementation are: (1) which nematode is most effective in suppressing the target pest under field conditions? and (2) what is the impact of various irrigation levels on field efficacy? We addressed these questions by comparing the efficacy of two nematodes, Steinernema riobrave and Steinernema feltiae (two nematodes that showed the highest virulence in prior lab assays and field trials) and an untreated control, at three irrigation levels 0, 1 and 6 irrigation events applied during a two-week period post-application. C. Nenuphar larvae were added to mini-plots prior to treatment application. Treatment effects were assessed by comparing the number of C. Nenuphar adults emerging from each plot. The experiments were conducted at two field sites (apple orchards in Kearneysville, West Virginia and Belchertown, Massachusetts) in 2011 and 2012. Relative to the untreated check, S. riobrave caused 85.0% and 97.3% control in 2011 and 2012 in Massachusetts (respectively) and 100% control in West Virginia both years, whereas S. feltiae caused 0% and 84.6% control in 2011 and 2012 (respectively) in Massachusetts, and 78.2% and 69.7% control in West Virginia. The level of C. Nenuphar suppression caused by S. riobrave was higher than suppression by S. feltiae at both sites in 2011 (no differences were detected in 2012). Irrigation did not have a significant effect on C. Nenuphar suppression at both sites and in both years of the experiments. The lack of irrigation effects is an unusual finding for field applications using entomopathogenic nematodes, and may have been due to the level of precipitation and water-holding capacity in the field soils tested. The results of this study have positive implications for the potential of incorporating entomopathogenic nematodes into a C. Nenuphar management program.

Eric J. Hoffmann - One of the best experts on this subject based on the ideXlab platform.

  • plum curculio coleoptera curculionidae adult mortality and associated fruit injury after exposure to field aged insecticides on tart cherry branches
    Journal of Economic Entomology, 2010
    Co-Authors: Eric J. Hoffmann, Christine Vandervoort, John C. Wise
    Abstract:

    ABSTRACT Plum curculio, Conotrachelus Nenuphar (Herbst) (Coleoptera: Curculionidae), adults were exposed to field-aged residues of thiamethoxam, acetamiprid, thiacloprid, indoxacarb, or azinphos-methyl on tart cherry, Prunus cerasus L. variety Montmorency. At 1, 3, 7, and 14 d postapplication, fruit were sampled for chemical residues, and bioassays were used to assess beetle mortality and plant tissue injury. Azinphos-methyl had lethal activity within 1 d of exposure at all postapplication intervals and significant fruit protection extended to 14 d postapplication. All of the neonicotinoids had lethal activity at 3 d posttreatment, with acetamiprid activity extending to 7 d. Antifeedant and oviposition deterrent effects were seen with thiamethoxam and thiacloprid; damage incidence was significantly reduced in the absence of significant beetle mortality or intoxication. Thiamethoxam and acetamiprid penetrated into leaf and fruit tissue and were detected in the interior tissues at 14 d postapplication, but ...

  • Ovicidal Activity of Organophosphate, Oxadiazine, Neonicotinoid and Insect Growth Regulator Chemistries on Northern Strain Plum Curculio, Conotrachelus Nenuphar
    Journal of Insect Science, 2008
    Co-Authors: Eric J. Hoffmann, Samantha M. Middleton, John C. Wise
    Abstract:

    An in vitro method was developed for assessing ovicidal effects of the organophosphate azinphos-methyl, the neonicotioids thiacloprid, thiamethoxam and clothianidin, the oxadiazine indoxacarb and the insect growth regulators novaluron and pyriproxifen on the plum curculio, Conotrachelus Nenuphar (Herbst)(Coleoptera: Curculionidae). The baseline survivorship of this method was 88 percent. Plum curculio eggs were most sensitive to azinphos-methyl. Thiacloprid, clothianidin and the chitin synthesis inhibitor, novaluron, had LC50 values below 100 ppm. Thiamethoxam, indoxacarb and pyriproxifen were not ovicidal at 100 ppm. Octanol-water partitioning coefficients, log Kow, appeared to be an important indicator of ovicidal activity within the neonicotinoids. This new bioassay method eliminates the confounding of the insect-chemical and plant-chemical interactions and the results highlight the utility of a post-infestation curative approach to plum curculio management.

  • novel life stage targets against plum curculio Conotrachelus Nenuphar herbst in apple integrated pest management
    Pest Management Science, 2007
    Co-Authors: John C. Wise, Eric J. Hoffmann, Ki Duk Kim, Christine Vandervoort, Ayhan Gokce, Mark E. Whalon
    Abstract:

    In this study the authors employed the plant-insect-chemistry (PIC) triad to investigate two novel life stage targets against the plum curculio (PC), Conotrachelus Nenuphar (Herbst), in apple integrated pest management (IPM). Laboratory treated apple bioassays were used to determine if the insect growth regulator (IGR) insecticides novaluron and tebufenozide have physiological effects on PC larvae following adult exposure. Curative activity bioassays were conducted for IGR, neonicotinoid, oxidiazine and organophosphate insecticides on PC larvae post-infestation, and fruit penetration profiles of insecticides were developed. The results revealed that novaluron exhibits activity on PC larvae via vertical transmission following exposure of mated females to treated substrate. Surface treatments of azinphos-methyl, thiacloprid and thiamethoxam to preinfested fruit resulted in significant reductions in larval emergence. For all compounds, 50% or more of the total recovered active ingredient was from apple skin, and for azinphos-methyl, indoxacarb and thiamethoxam it was greater than 80%. For azinphos-methyl, novaluron, methoxyfenozide and thiacloprid, however, active ingredient was recovered from every section of the apple, from skin to core. Implications for twenty-first century IPM are discussed.

  • Pyriproxyfen activates reproduction in prediapause northern strain plum curculio (Conotrachelus Nenuphar Herbst)
    Pest management science, 2007
    Co-Authors: Eric J. Hoffmann, Joshua Vanderjagt, Mark E. Whalon
    Abstract:

    Field-collected, prediapause northern strain plum curculio, Conotrachelus Nenuphar (Herbst), adults were treated with the juvenile hormone analogue pyriproxyfen to assess effects on reproductive development. Adults of this pest have an obligate winter reproductive diapause and do not reach reproductive maturity until after spring emergence. Topical (1.0 µL) doses of 10, 1.0 and 0.1 µg µL−1 pyriproxyfen induced oocyte development and reproductive maturation in all treated females as assessed by dissection. There was no increased mortality in treated beetles, and control insects showed no reproductive maturation. Treatment of prediapause males and females with 1.0 µg µL−1 of topical pyriproxyfen or exposure to residues on fruit induced successful egg laying and F1 emergence; F1 pupation success in topical treatments and residue exposure was 47 and 59% respectively. Filial adults require re-exposure to initiate reproductive development. Treatment protocols with pyriproxyfen will allow researchers to culture the northern strain, instead of relying exclusively on the non-diapausing southern strain. Copyright © 2007 Society of Chemical Industry

  • Reproductive Development of Northern and Southern Strains of Plum Curculio (Coleoptera: Curculionidae)
    Journal of economic entomology, 2004
    Co-Authors: Eric J. Hoffmann, Andrea B. Coombs, Mark E. Whalon
    Abstract:

    Abstract Laboratory-reared southern and field-collected northern strains of plum curculio, Conotrachelus Nenuphar (Herbst), were sampled to examine the relationship between degree-day (DD) accumulation and female reproductive development, as measured by mating status, oocyte size, and number of oocytes. The overall goal was to generate an objective degree-day model for predicting damage potential that could be applied to various host commodities rather than relying on separate biofix models for each crop. Adult beetles were dissected to measure mating status, maximum oocyte size, and number of oocytes. Southern strain beetles reared at 25°C initiated mating 9 d after eclosion and did not require mating to induce oocyte development. By 20 d posteclosion, unmated females had significantly higher egg loads compared with mated females of the same age. Logistic regression analysis suggests that southern and northern strain beetles had a stable maximum oocyte length of 62 and 72 μm, respectively. Northern strai...

Henry Y. Fadamiro - One of the best experts on this subject based on the ideXlab platform.

  • Behavioral Response of Plum Curculio, Conotrachelus Nenuphar, to Synthetic Fruit Volatile Lures and the Male-Produced Aggregation Pheromone
    Psyche: A Journal of Entomology, 2015
    Co-Authors: Clement Akotsen-mensah, Henry Y. Fadamiro
    Abstract:

    Plum curculio, Conotrachelus Nenuphar Herbst (Coleoptera: Curculionidae), is a key pest of stone and pome fruits in North America. The behavioral response of adults of different physiological states (sex, age, diet, and mating status) to three commercially available synthetic lures, benzaldehyde (BZ) and plum essence (PE), the male-produced aggregation pheromone, grandisoic acid (GA), or their combinations, was studied in the laboratory. Four choice olfactometer bioassays demonstrated significant attraction of both sexes to PE lure. Both BZ and GA lures were not attractive to plum curculio when tested as commercially formulated. PE had higher release rate (1.51 mg/hr) than BZ (0.36 mg/hr) and GA (ca. 0.04 mg/hr), suggesting that the higher attractiveness of PE may be due to its relatively higher release rates. Tests with combined lures showed a neutral effect of combining GA with PE and an inhibitory effect of combining BZ with PE. The physiological conditions of the weevils had no significant effect on their response to the lures. Olfactometer tests with pure 1,2,4-trichlorobenzene (TCB) confirmed that this compound was inhibitory to plum curculio. These results are discussed in relation to the contrasting field reports which implicated BZ + GA as an effective attractant for plum curculio.

  • Influence of Orchard Weed Management Practices on Soil Dwelling Stages of Plum Curculio, Conotrachelus Nenuphar (Coleoptera: Curculionidae)
    Florida Entomologist, 2012
    Co-Authors: Clement Akotsen-mensah, Robert T. Boozer, Henry Y. Fadamiro
    Abstract:

    ABSTRACT Plum curculio, Conotrachelus Nenuphar Herbst (Coleoptera: Curculionidae), is a key pest of peaches in the southeastern United States. Part of its life cycle, specifically, the pre-pupal, pupal and pre-adult stages are spent in the soil. Experiments were conducted in 2 peach orchards to evaluate the effects of some common orchard weed management practices on the development of the soil dwelling life stages of plum curculio. Four common orchard weed management practices (treatments) were evaluated in plots (3 m × 3 m) located under peach tree canopies: centipede grass, Eremochloa ophiuroides (Munro) understory (soil covered with centipede grass); weed free understory (bare soil, weeds removed with herbicide sprays); weedy (natural weeds) understory; and pine bark understory (soil covered with pine bark). Fewer numbers of adult plum curculio emerged from the centipede grass understory plots compared with weed free, weedy or pine bark treated understories. Similar results were obtained in the greenho...

  • Seasonal Occurrence and Development of Degree-Day Models for Predicting Activity of Conotrachelus Nenuphar (Coleoptera: Curculionidae) in Alabama Peaches
    Annals of the Entomological Society of America, 2011
    Co-Authors: Clement Akotsen-mensah, Robert T. Boozer, Arthur G. Appel, Henry Y. Fadamiro
    Abstract:

    ABSTRACT The plum curculio, Conotrachelus Nenuphar (Herbst) (Coleoptera: Curculionidae), is a key pest of peaches, Prunus persica (L.) Batsch, in North America. Captures of adult weevils in unbaited pyramid traps recorded annually from 2000 to 2008 in an unmanaged peach orchard in central Alabama were used to determine its seasonal occurrence and to develop predictive degree-day models. Spring migration of plum curculio began at bloom (early to mid-March). Linear, polynomial, and three-parameter Weibull functions were tested to describe the relationship between weekly trap capture and cumulative degree-day (DD). Criteria used to select the best models were the smallest Akaike information criterion and highest R2 values. A sixth-order polynomial function fitted best to seasonal trap captures and cumulative DDs and revealed two major seasonal peaks with the first (spring generation) and second (summer generation) peaks occurring at cumulative DDs of ≈245 and 1105 (base 10°C, biofix of 1 January), respective...

  • Field evaluation of reduced insecticide spray programs for managing plum curculio, Conotrachelus Nenuphar (Coleoptera: Curculionidae), in Alabama peaches.
    Pest management science, 2011
    Co-Authors: Clement Akotsen-mensah, Robert T. Boozer, Henry Y. Fadamiro
    Abstract:

    BACKGROUND: Plum curculio (PC), Conotrachelus Nenuphar (Herbst.), is an important pest of peaches in the southeastern United States. Commercially acceptable control of this insect is typically achieved by weekly or biweekly application of broad-spectrum conventional insecticides, resulting in 6–12 sprays per season. Experiments were conducted in a peach orchard in Alabama during 2007–2009 to compare the conventional calendar-based insecticide spray program involving weekly applications of phosmet with three different reduced spray programs using three targeted (well-timed) insecticide sprays (TIS) of phosmet, permethrin or thiamethoxam applied in an alternated fashion. RESULTS: All three TIS programs significantly reduced PC damage at harvest compared with the untreated control in two of the three years (2008 and 2009). Fruit damage due to stink bugs, which are emerging pests of peaches in the region, was also significantly reduced in the TIS programs in both years. In a separate trial in which one of the TIS programs (three targeted sprays of phosmet) was evaluated in a larger peach block in 2009, percentage fruit damage due to PC increased from < 1% in June to ∼4% in late July. CONCLUSION: All the TIS programs evaluated provided effective control of PC and represent potential alternatives to the conventional weekly spray program in peaches with concomitant reduction in insecticide usage and associated costs. However, an additional spray may be necessary for effective control of PC and stink bugs in late-season peach varieties. Copyright © 2011 Society of Chemical Industry

Dan L. Horton - One of the best experts on this subject based on the ideXlab platform.

  • Control of plum curculio, Conotrachelus Nenuphar, with entomopathogenic nematodes: Effects of application timing, alternate host plant, and nematode strain
    Biological Control, 2008
    Co-Authors: David I. Shapiro-ilan, Russell F. Mizell, Ted E. Cottrell, Dan L. Horton
    Abstract:

    Abstract In prior research, we established that soil applications of Steinernema riobrave in peach orchards that target plum curculio, Conotrachelus Nenuphar , larvae can result in high levels of control (78–100%). In this study, we investigated the potential of using entomopathogenic nematodes to control C. Nenuphar further by evaluating (1) field efficacy of late-term nematode applications, i.e., that target C. nenupha r after the onset of adult emergence, (2) control C. Nenuphar larvae in an alternate host, i.e., wild plum, Prunus angustifolia , and (3) laboratory virulence of different Steinernema carpocapsae and S. riobrave strains. In 2004 and 2005, late-term applications of S. carpocapsae (All strain) and S. riobrave (355 strain) in a peach orchard in Quincy, Florida failed to cause any measurable control. In field tests targeting C. Nenuphar larvae in a wild plum thicket (Byron, Georgia), S. riobrave (355 strain) caused 100% control (both years), and S. riobrave (3-8b strain) caused 98.6% and 87.9% control in 2005 and 2006, respectively. Applications in alternate hosts could reduce C. Nenuphar immigration into the orchard. Laboratory experiments detected differential virulence to C. Nenuphar larvae in S. carpocapsae (All strain) and six strains of S. riobrave ; among the most virulent were the 3-2, 3-3, and 355 strains of S. riobrave . Pathogenicity to adult C. Nenuphar in the laboratory was not detected in five S. riobrave strains, but was detected in four S. carpocapsae strains (All, Agriotos, Italian and Sal) but not in two others (Kapow and Mexican). We conclude that soil applications with entomopathogenic nematodes can cause high levels of C. Nenuphar control in peach or alternate hosts, but timing of application and the choice of nematode species or strain can be important.

  • Hosts of plum curculio, Conotrachelus Nenuphar (Coleoptera: Curculionidae), in Central Georgia.
    Environmental Entomology, 2006
    Co-Authors: David A. Jenkins, Ted E. Cottrell, Dan L. Horton, Amanda Hodges, Greg Hodges
    Abstract:

    Potential host plants for the larvae of plum curculio, Conotrachelus Nenuphar (Herbst) (Coleoptera: Curculionidae), in central Georgia's peach producing region were surveyed. This fruit-attacking curculionid is reported to have a broad host range, including many plants in the Rosaceae and other families. However, our collections indicated that in this region plum curculio largely is limited to peach (Prunus persica) and plum (P. angustifolia and P. umbellata). Abandoned peach orchards and wild plum thickets are important hosts for the spring generation of plum curculio and are sources of subsequent infestations of managed peach orchards. However, only abandoned peach orchards were available to the summer generation of plum curculio. May haw, Crataegus aestivalis, was also a host, but other species of Crataegus were not used. Although the plum curculio was reported to be a significant pest of blueberries (Vaccinium spp.) in North Carolina, New Jersey, and Delaware, they were only rarely used as a host in central Georgia. Apple (Malus domestica) and Asian pear (Pyrus pyrifolia), when available, were ovipositional hosts of plum curculio in central Georgia; however, no larvae emerged from these hosts. We report the first records of plum curculio developing in Vaccinium stamineum and Vitis rotundifolia. Our results are compared with a previous survey conducted in the northeastern United States, as well as to data reported in the literature.

  • INVERTEBRATE PREDATORS AND PARASITOIDS OF PLUM CURCULIO, Conotrachelus Nenuphar (COLEOPTERA: CURCULIONIDAE) IN GEORGIA AND FLORIDA
    Florida Entomologist, 2006
    Co-Authors: David A. Jenkins, David I. Shapiro-ilan, Ted E. Cottrell, Russ F. Mizell, Dan L. Horton
    Abstract:

    The extent of predation and parasitism on larvae of the plum curculio, Conotrachelus Nenuphar (Herbst) (Coleoptera: Curculionidae), was measured independently with several different experimental designs at sites in northern Florida and central Georgia. Experimental manipulation in Monticello, FL, and in Byron, GA, demonstrated equivocal impacts by predation. However, direct observations in Byron, GA, revealed that ants are the dominant invertebrate predators of plum curculio larvae, causing up to 62% mortality. Primary ant predators included Solenopsis invicta (Buren) (Hymenoptera: Formicidae) and Dorymyrmex bureni (Trager) (Hymenoptera: Formicidae). Predation may be more important later in the season when infested fruit does not abscise and plum curculio larvae must drop to the ground from the trees and spend a considerable time burrowing into the soil. This contrasts with the early season when infested fruit abscise and larvae crawl from the fruit directly into the soil, reducing their exposure to predators. Recorded parasites included Nealiolus curculionis (Fitch) (Hymenoptera: Braconidae) and Cholomyia inaequipes Bigot (Diptera: Tachinidae). Parasitism, particularly by N. curculionis, was common in northern Florida but rare in middle Georgia.

  • Dermal Efficacy Evaluation of New Insecticides for Control of Plum Curculio in Peaches
    International Journal of Fruit Science, 2005
    Co-Authors: Wheeler G. Foshee, Dan L. Horton, Robert T. Boozer, Eugene K. Blythe, Johnny T. Staples
    Abstract:

    Abstract Labeled rates of bifenthrin (Capture® 4EC, 112 mg a.i. ha-1), fipronil (Regent® 4SC, 280 mg a.i.-ha-1), malathion (Bonide® 50% Malathion, 560 mg a.i.-ha-1), thiacloprid (Calypso® 4EC, 288 mg a.i.-ha-1), thiamethoxam (Actara® 25WG, 87 mg a.i.-ha-1), and twice the labeled rates of these same insecticides, were examined (along with an untreated control) for dermal efficacy against plum curculio, Conotrachelus Nenuphar (Herbst) (Coleoptera: Curculionidae). Plum curculios treated with labeled rates of fipronil, bifenthrin, and malathion exhibited higher mortality (by no later than 96 hours post-application) than plum curculios left untreated or treated with labeled rates of thiamethoxam and thiacloprid. At 24 h post-application, malathion at the labeled rate, malathion at twice the labeled rate, and bifenthrin at twice the labeled rate resulted in > 90% efficacy. Fipronil at twice the labeled rate produced an acceptable level of control (≤90% mortality) by 48 h post-application. This rapid laboratory ...

  • Temperature-dependent development and prediction of emergence of the summer generation of plum curculio (Coleoptera: Curculionidae) in the southeastern United States.
    Environmental Entomology, 2004
    Co-Authors: Z. Lan, Harald Scherm, Dan L. Horton
    Abstract:

    Abstract Timely insecticide application against the summer generation (first field generation) of the plum curculio, Conotrachelus Nenuphar Herbst, is critical in the production of peach and other stone fruits in the southeastern United States. In the absence of monitoring tools that are effective during midseason when the adults of this generation emerge, a temperature-based emergence model would be useful as an alternative decision aid. In this study, we determined rates of larval development (from oviposition to peak emergence of larvae) and pupal development (from larval emergence to peak emergence of adults) for two populations of C. Nenuphar in constant temperatures ranging from ≈11–37°C, developed linear regression models to describe the relationships between developmental rate and temperature for both stages, and estimated degree-day requirements for completing development from these models. The lower threshold temperature was 11.1 and 8.7°C for larval and pupal development, respectively. The ther...