The Experts below are selected from a list of 306 Experts worldwide ranked by ideXlab platform
Wendell L. Roelofs - One of the best experts on this subject based on the ideXlab platform.
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Characterization of Z/E11- and Z9-desaturases from the obliquebanded leafroller moth, Choristoneura rosaceana.
Journal of insect science (Online), 2002Co-Authors: Marion O'connor, Wendell L. RoelofsAbstract:A (triangle up) 11-desaturase gene was cloned from the sex pheromone gland of the obliquebanded leafroller moth, Choristoneura rosaceana. The desaturase cDNA sequence spans 1300 nucleotides with an open reading frame encoding a 335 amino-acid protein, which has 81% identity to a Z/E11-desaturase of the redbanded leafroller moth, Argyrotaenia velutinana. A functional assay with a pYES2 yeast expression system demonstrated that the (triangle up) 11-desaturase exhibits unusual substrate and stereospecificities in producing a Z/E11 mixture (7:1) of only C14 acids. A metabolic Z9-desaturase also was cloned from fat body of this species, and proved to be in the class that produces more Z9-16:Acid than Z9-18:Acid.
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Characterization of Z/E11- and Z9-desaturases from the obliquebanded leafroller moth, Choristoneura rosaceana
Journal of Insect Science, 2002Co-Authors: Marion O'connor, Wendell L. RoelofsAbstract:Abstract A ▵11-desaturase gene was cloned from the sex pheromone gland of the obliquebanded leafroller moth, Choristoneura rosaceana. The desaturase cDNA sequence spans 1300 nucleotides with an open reading frame encoding a 335 amino-acid protein, which has 81% identity to a Z/E11-desaturase of the redbanded leafroller moth, Argyrotaenia velutinana. A functional assay with a pYES2 yeast expression system demonstrated that the ▵11-desaturase exhibits unusual substrate and stereospecificities in producing a Z/E11 mixture (7:1) of only C14 acids. A metabolic Z9-desaturase also was cloned from fat body of this species, and proved to be in the class that produces more Z9-16:Acid than Z9-18:Acid.
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Interference with the mate-finding communication system of the obliquebanded leafroller (Lepidoptera: Tortricidae) using synthetic sex pheromones
Environmental Entomology, 1996Co-Authors: D. S. Lawson, W. H. Reissig, Arthur M. Agnello, Jan P. Nyrop, Wendell L. RoelofsAbstract:Effect of atmospheric permeation with synthetic sex pheromone on the behavior and control of obliquebanded leafroller, Choristoneura rosaceana (Harris), was studied in small and large plots in commercial apple orchards. Synthetic sex pheromone significantly reduced the ability of male moths to locate pheromone-baited traps and tethered females; however, no differences were found among 3 pheromone rates. Location of pheromone dispensers within the tree canopy did not alter the number of males locating pheromone-baited traps and mating tethered females. Obliquebanded leafroller activity was greatest in the upper positions of the tree canopy and no edge effect was observed around perimeters of large disrupted blocks. The presence of gravid feral females, mated tethered females, high larval densities, and fruit damage within large pheromone disrupted blocks indicate obliqubanded Leafrollers mate in orchards treated with synthetic sex pheromone. However, fruit damage caused by obliquebanded leafroller larvae was similar in pheromone, pheromone plus insecticide, and insecticide treatments.
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Control of pheromone biosynthesis in mated redbanded leafroller moths
Archives of Insect Biochemistry and Physiology, 1993Co-Authors: Russell A. Jurenka, Gemma Fabriás, Sonny B. Ramaswamy, Wendell L. RoelofsAbstract:Mating in the redbanded leafroller moth, Argyrotaenia velutinana, causes a permanent decline in pheromone titers. Three hours following the termination of mating, phermone titers were significantly decreased from premating levels, and titers remained low for at least four days after mating. Pheromone titers were similar in females that had been decapitated or mated for twenty-four hours. In the redbanded leafroller moth, two peptides control pheromone production. The pheromone biosynthesis activating neuropeptide is produced in the brain and the pheromonotropic bursa peptide is produced in the corpus bursae. Both peptides stimulated pheromone biosynthesis in mated females and extracts prepared from brains and bursae of mated females contained pheromonotropic activity. However, severing the ventral nerve cord before mating prevented the decline in pheromone titer that occurred in mated females. Hemolymph collected during scotophase from mated females did not have pheromonotropic activity, whereas hemolymph collected during scotophase from virgin females contained activity. These results indicate that mating produces a signal sent by the ventral nerve cord to the brain to stop the release of pheromone biosynthesis activating neuropeptide. © 1993 Wiley-Liss, Inc.
Jay F Brunner - One of the best experts on this subject based on the ideXlab platform.
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Mating Disruption/SIR Codling moth and leafroller mating disruption evaluated using sprayable pheromones
2020Co-Authors: Betsy Valdez, Jay F BrunnerAbstract:The effect of sprayable pheromones (Suterra, Inc. and 3M Corp.) was evaluated for codling moth and obliquebanded leafroller in commercial orchards. Codling moth sprayable treatments were applied at varying rates (5, 10, 20 and 40 grams AI per acre) and compared with either a non-pheromone treated area or one treated with hand-applied dispensers (Isomate C+, 200 and 400 dpa, Pacific Biocontrol Corp.). Leafroller sprayable treatments were applied at four rates (1, 2.5, 10 and 20 grams AI per acre) and compared to a non-pheromone treated area at each location. Each treatment block was monitored with large delta-style traps baited with a standard load pheromone lure and/or a high-load (10X) pheromone lure. To determine female and male activity, the "DA" lure was used for codling moth and the acetic acid lure for leafroller. Females collected from the "DA" and acetic acid baited traps were dissected in the laboratory to determine mating status. Leafroller larval densities were evaluated throughout the season and fruit injury was evaluated at harvest. Codling moth fruit injury was evaluated after 1 st and 2 nd generations. Although codling moth and leafroller sprayable pheromone did reduce capture in most pheromone-baited traps, no consistent pattern of decreased larval populations or fruit injury was noted. Mating success for both codling moth and leafroller was not significantly different between treatments.
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parasitism of Leafrollers in washington fruit orchards is enhanced by perimeter plantings of rose and strawberry
Biological Control, 2012Co-Authors: Thomas R Unruh, Robert S Pfannenstiel, Catharine Peters, Jay F Brunner, Vincent P JonesAbstract:Abstract Pandemis pyrusana and Choristoneura rosaceana (Lepidoptera: Tortricidae) are dominant leafroller pests in fruit orchards in Washington State. Parasitism rates of orchard Leafrollers are low in spring and moderate in summer. In a previous study, parasitism rates of Leafrollers were high in two orchards adjacent to thickets of Rosa woodsii. Here we show that plantings of R. woodsii and strawberry can significantly increase parasitism rates of Leafrollers in adjacent orchards. In late summer of 2000, R. woodsii and strawberries were planted near four apple orchards and plantings were infested with the strawberry leafroller, Ancylis comptana, which overwinters as mature larvae on rose. In fall, these larvae were parasitized by Colpoclypeus florus (Hymenoptera: Eulophidae), a leafroller parasitoid of European origin that was recently discovered in central Washington. In the following spring of 2001, moderate rates of parasitism by C. florus were observed on P. pyrusana larvae placed along transects in apple orchards up to 200 m from three experimental plantings. Parasitism by C. florus increased in summer and was observed up to 500 m from the plantings. This pattern of parasitism by C. florus was observed through 2005 at one site. In contrast, little or no parasitism by C. florus was observed at these sites in 1999 and 2000 before planting of the rose habitats. Using a protein marking technique, self-marked C. florus originating from a marked rose planting were captured up to 100 m away in an adjacent orchard. We conclude that rose and strawberry plantings showed potential value as a sustainable landscape modification to improve biological control of Leafrollers in Washington fruit orchards.
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overwintering hosts for the exotic leafroller parasitoid colpoclypeus florus implications for habitat manipulation to augment biological control of Leafrollers in pome fruits
Journal of Insect Science, 2010Co-Authors: Thomas R Unruh, R.s Pfannenstiel, Jay F BrunnerAbstract:Thirty sites of managed and native habitats were surveyed for Leafrollers (Lepidoptera: Tortricidae) in the apple producing region of central Washington State and northern Oregon from September through November 1997–2000 to discover species that supported overwintering by the parasitoid Colpoclypeus florus (Walker) (Hymenoptera: Eulophidae). C. florus, a species introduced from Europe, requires medium to large host larvae late in autumn on which to overwinter, and few leafroller species display this biology. Over the four years, five potential C. florus hosts were collected, including: Ancylis comptana (Froelich), Xenotemna pallorana (Robinson), and Syndemis sp. (Tortricidae), Filatima sp. (Gelechiidae), and Caloptilia burgessiellia (Zeller) (Gracillariidae). Of these, A. comptana, Syndemis sp., and Filatima sp. have been confirmed as overwintering hosts for C. florus. During the four years, the Syndemis sp. was rare and observed at only one location feeding on redosier dogwood, Cornus sericea L. (Cornales: Cornaceae) although, at this location, many of the larvae collected were parasitized by C. florus. Filatima sp. was common in the Yakima valley feeding on balsam poplar, Populus balsamifera L. ssp. trichocarpa (Torr. & Gray ex Hook) Brayshaw (Malpighiales: Salicaceae) but was rarely parasitized. A. comptana, however, was collected at many locations in central Washington and was frequently found as an overwintering host for C. florus. A. comptana was found feeding on two Rosaceae: Wood's rose, Rosa woodsii Lindl., and strawberry, Fragaria ananassa Duchesne (Rosales: Rosaceae). Based on the number of host larvae collected, A. comptana appears to be the primary overwintering host for C. florus in Washington. Introduction of A. comptana populations to near-orchard habitats may facilitate biological control of Leafrollers that are orchard pests.
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Comparison of Delayed Female Mating on Reproductive Biology of Codling Moth and Obliquebanded Leafroller
Environmental Entomology, 2008Co-Authors: Vincent P Jones, Nik G. Wiman, Jay F BrunnerAbstract: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 field-based adult longevity estimates showed that codling moth females experiencing >2-d delay in mating resulted in decreases in population density or extinction within two generations. In contrast, obliquebanded leafroller females delayed
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resistance and cross resistance in populations of the Leafrollers choristoneura rosaceana and pandemis pyrusana in washington apples
Journal of Insect Science, 2006Co-Authors: John E Dunley, Jay F Brunner, M D Doerr, Elizabeth H BeersAbstract:Insecticide bioassays of the Leafrollers, Choristoneura rosaceana (Harris), and Pandemis pyrusana Kearfott (Lepidoptera: Tortricidae), were used to investigate resistance and cross-resistance between azinphosmethyl and other insecticides. Comparisons of field-collected populations with susceptible laboratory colonies of both leafroller species were made in 1996-97, prior to registration and field introduction of several of insecticides, and were re-tested in 2000-2001 following several years of use in the field. Insecticides tested included azinphosmethyl, chlorpyrifos, methyl parathion, tebufenozide, methoxyfenozide, spinosad, indoxacarb, acetamiprid, Bacillus thuringiensis, and azadirachtin. Azinphosmethyl-susceptible laboratory colonies were used for comparison to field populations. Resistance to azinphosmethyl was found in all populations of C. rosaceana (5.2-26.8 fold) and P. pyrusana (8.4-24.9 fold) collected from commercial orchards. Cross-resistance between azinphosmethyl and the insect growth regulators tebufenozide and methoxyfenozide was found in all but one population of the two leafroller species. No cross-resistance was found to chlorpyrifos. Some of the populations tested were cross-resistant to spinosad and indoxacarb, but the responses to these materials were more variable.
Vincent P Jones - One of the best experts on this subject based on the ideXlab platform.
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Longevity of the Adult Codling Moth, Cydia pomonella, and the Obliquebanded Leafroller, Choristoneura rosaceana, in Washington Apple Orchards
Journal of Insect Science, 2020Co-Authors: Vincent P Jones, Nik G. WimanAbstract: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.
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parasitism of Leafrollers in washington fruit orchards is enhanced by perimeter plantings of rose and strawberry
Biological Control, 2012Co-Authors: Thomas R Unruh, Robert S Pfannenstiel, Catharine Peters, Jay F Brunner, Vincent P JonesAbstract:Abstract Pandemis pyrusana and Choristoneura rosaceana (Lepidoptera: Tortricidae) are dominant leafroller pests in fruit orchards in Washington State. Parasitism rates of orchard Leafrollers are low in spring and moderate in summer. In a previous study, parasitism rates of Leafrollers were high in two orchards adjacent to thickets of Rosa woodsii. Here we show that plantings of R. woodsii and strawberry can significantly increase parasitism rates of Leafrollers in adjacent orchards. In late summer of 2000, R. woodsii and strawberries were planted near four apple orchards and plantings were infested with the strawberry leafroller, Ancylis comptana, which overwinters as mature larvae on rose. In fall, these larvae were parasitized by Colpoclypeus florus (Hymenoptera: Eulophidae), a leafroller parasitoid of European origin that was recently discovered in central Washington. In the following spring of 2001, moderate rates of parasitism by C. florus were observed on P. pyrusana larvae placed along transects in apple orchards up to 200 m from three experimental plantings. Parasitism by C. florus increased in summer and was observed up to 500 m from the plantings. This pattern of parasitism by C. florus was observed through 2005 at one site. In contrast, little or no parasitism by C. florus was observed at these sites in 1999 and 2000 before planting of the rose habitats. Using a protein marking technique, self-marked C. florus originating from a marked rose planting were captured up to 100 m away in an adjacent orchard. We conclude that rose and strawberry plantings showed potential value as a sustainable landscape modification to improve biological control of Leafrollers in Washington fruit orchards.
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Comparison of Delayed Female Mating on Reproductive Biology of Codling Moth and Obliquebanded Leafroller
Environmental Entomology, 2008Co-Authors: Vincent P Jones, Nik G. Wiman, Jay F BrunnerAbstract: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 field-based adult longevity estimates showed that codling moth females experiencing >2-d delay in mating resulted in decreases in population density or extinction within two generations. In contrast, obliquebanded leafroller females delayed
Lisa A Berndt - One of the best experts on this subject based on the ideXlab platform.
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Effects of alyssum flowers on the longevity, fecundity, and sex ratio of the leafroller parasitoid Dolichogenidea tasmanica
Biological Control, 2020Co-Authors: Lisa A Berndt, Steve D. WrattenAbstract:A laboratory experiment assessed the effect of floral food resources on the longevity, fecundity, and sex ratio of Dolichogenidea tasmanica (Cameron) (Hymenoptera: Braconidae), a parasitoid of Leafrollers (Lepidoptera: Tortricidae). Alyssum (Lobularia maritima (L.), Brassicaceae) plants with flowers were compared with plants without flowers, with water available in both treatments. Adult parasitoids were provided with an excess of second-instar larval hosts, which were then reared to determine the composition of the F1 parasitoid generation. Female parasitoids with access to alyssum flowers lived, on average, seven times longer than those without flowers. Male longevity was three times greater with, than without flowers. The lifetime realised fecundity of D. tasmanica was also significantly increased in the presence of flowers, although this was a consequence of the increase in longevity, rather than an increase in daily fecundity. Without flowers, offspring sex ratios were strongly male biased, but when females had access to flowers an approximately equal sex ratio was produced. These results are discussed in relation to the use of flowers in agroecosystems for the conservation biological control of leafroller pests.
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the influence of floral resource subsidies on parasitism rates of Leafrollers lepidoptera tortricidae in new zealand vineyards
Biological Control, 2006Co-Authors: Lisa A Berndt, S D Wratten, S L ScarrattAbstract:Abstract Biological control of pests in agroecosystems may be enhanced by the use of habitat manipulation techniques to provide floral and other ‘resource subsidies’ for natural enemies. This was examined in vineyards by adding flowering buckwheat ( Fagopyrum esculentum Moench) and assessing the effect of this on the parasitism rate of leafroller (Lepidoptera: Tortricidae) larvae. Leafroller larvae were collected from vines in plots with and without buckwheat flowers at two commercial vineyards in Marlborough, New Zealand. At one vineyard, the parasitism of these pests was increased by more than 50% when buckwheat flowers were present. At the other, buckwheat had no effect, however leafroller populations were lower and insecticides had been used in part of the experiment. The presence of buckwheat did not reduce leafroller abundance during the two months of the study. These results show that habitat manipulation, by providing floral resource subsidies for parasitoids, can enhance parasitism rate. However, the value of this technique for reducing damage done by Leafrollers in the vineyard system studied remains to be determined.
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Effects of buckwheat flowers on leafroller (Lepidoptera: Tortricidae) parasitoids in a New Zealand vineyard
Agricultural and Forest Entomology, 2002Co-Authors: Lisa A Berndt, Steve D. Wratten, Paul G. HassanAbstract:Abstract 1 The provision of floral resources in agricultural ecosystems can potentially enhance biological control of pests by providing nutrients to parasitoids. To test this, the effect of buckwheat Fagopyrum esculentum Moench flowers on leafroller parasitoids was investigated in a New Zealand vineyard. 2 Relative abundance of parasitoids was assessed with yellow sticky traps in buckwheat and control plots. Male Dolichogenidea tasmanica (Cameron) (Hymenoptera: Braconidae) were significantly more abundant in the presence of buckwheat. No significant result was found for female D. tasmanica or either sex of Glyptapanteles demeter (Wilkinson) (Hymenoptera: Braconidae), the other leafroller parasitoid caught. 3 The relative parasitism rate of Leafrollers by D. tasmanica was assessed with a leafroller release and recover technique. No difference in parasitism was found between buckwheat and control plots. 4 The sex ratio (% males) of D. tasmanica emerging from recovered leafroller larvae was significantly lower in the presence of buckwheat than in control plots on one of the two release dates. Possible reasons for this increase in female production are discussed.
D.j. Rogers - One of the best experts on this subject based on the ideXlab platform.
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Understory influence on leafroller pupunations in Hawke's bay organic apple orchard
2020Co-Authors: D.j. Rogers, James T.s. Walker, I.c. Moen, F. Weibel, Peter L. Lo, L.m. ColeAbstract:Leafrollers (Tortricidae) were collected from apple foliage and understorey vegetation in six commercial organic apple orchards in Hawke’s Bay over one season. Assessments were made of plant species present in the understorey at the time of collection. All leafroller larvae were reared to adults on artificial diet to identify leafroller species and parasitoids. Nearly half (47%) of all Leafrollers collected in these orchards were located in the understorey, highlighting the importance of understorey and its management for the control of leafroller. Dock, clover and dandeliontype plants contributed 25% to the overall understorey, yet hosted 75% of the Leafrollers collected from the understorey. Dolichogenidea sp. was the most abundant parasitoid (79%) attacking Leafrollers found amongst the apple foliage, whereas Glyptapanteles demeter was dominant in the understorey (61%). Generally the number of Leafrollers in an orchard was proportional to the abundance of broadleaf weeds and inversely proportional to parasitis.
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use of mating disruption for control of new zealand Leafrollers in apple orchards
New Zealand Plant Protection, 2011Co-Authors: J T S Walker, D.j. Rogers, D M Suckling, P L Lo, Ashraf M Elsayed, T M Fraser, R M HornerAbstract:Leafrollers are important pests of apples and infested fruit can result in rejection of export consignments. Leafroller mating disruption using a pheromone blend with activity against three species was examined in 12 Hawke's Bay orchards over two seasons (2009- 10 and 2010-11). Pheromone dispensers (600/ha) and a single insecticide were applied to trees in early November, and subsequent insecticide use was based on leafroller pheromone trapping and thresholds. The pheromone blend substantially suppressed mating of virgin female lightbrown apple moth in treated orchards and reduced male catch in pheromone traps by up to 98% compared with the season prior to implementation. Insecticide use for leafroller control decreased accordingly, from 2.1-2.7 insecticides per block in 2008/09 to 1.0-1.8 in 2010/11. Leafroller control using mating disruption was acceptable, fruit damage varied from 0.3% to 0.16% and no leafroller larvae were found on fruit in both field assessments and phytosanitary inspections of packed cartons.
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Mortality of the leafroller parasitoid Dolichogenidea tasmanica (Hym: Braconidae) exposed to orchard pesticide residues.
New Zealand Plant Protection, 2004Co-Authors: I. C. Newman, J T S Walker, D.j. RogersAbstract:A laboratory bioassay was used to evaluate the effect of residues from 10 orchard pesticides on mortality of Dolichogenidea tasmanica, a parasitoid of Leafrollers. Adult parasitoids were caged in Petri dishes that had been sprayed with the field rate of the pesticides. Mortality was assessed over 7 days and classified using the laboratory criteria defined by the International Organization for Biological and Integrated Control of Noxious Animals and Plants. Residues of buprofezin, emamectin benzoate, lufenuron, tebufenozide and thiacloprid were harmless ( 99% mortality). The implications for leafroller control in pipfruit production programmes are discussed.
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UNDERSTOREY INFLUENCE ON LEAFROLLER POPULATIONS IN HAWKE'S BAY ORGANIC APPLE ORCHARDS
New Zealand Plant Protection, 2003Co-Authors: D.j. Rogers, James T.s. Walker, I.c. Moen, F. Weibel, Peter L. Lo, L.m. ColeAbstract:Leafrollers (Tortricidae) were collected from apple foliage and understorey vegetation in six commercial organic apple orchards in Hawke’s Bay over one season. Assessments were made of plant species present in the understorey at the time of collection. All leafroller larvae were reared to adults on artificial diet to identify leafroller species and parasitoids. Nearly half (47%) of all Leafrollers collected in these orchards were located in the understorey, highlighting the importance of understorey and its management for the control of leafroller. Dock, clover and dandeliontype plants contributed 25% to the overall understorey, yet hosted 75% of the Leafrollers collected from the understorey. Dolichogenidea sp. was the most abundant parasitoid (79%) attacking Leafrollers found amongst the apple foliage, whereas Glyptapanteles demeter was dominant in the understorey (61%). Generally the number of Leafrollers in an orchard was proportional to the abundance of broadleaf weeds and inversely proportional to parasitism.