Brief Summary of Minutes of Annual Meeting

WERA060 SAES-422: Brief Summary of Meeting Minutes (26-Mar-2009 to 27-Mar-2009) The following contributions to discussion were made by individual participants: Andy Wyenandt, Extension Specialist in Vegetable Pathology, Rutgers University updated the group on the fungicide resistance management guide for vegetable crop production that plant pathologists in the mid-Atlantic region have distributed since 2007. In 2008, approximately 2,000 guides were distributed to growers in the region and beyond. No grower survey was done in 2008 and a journal article was written for publication in Crop Management online (published in 3/09). Al Fournier, IPM Program Manager with University of Arizona, provided a presentation on measuring adoption of cross-commodity guidelines for whitefly management in Arizona Peter Ellsworth, IPM Coordinator with University of Arizona attended part of the meeting and participated in group discussions. Six publications / presentations related to resistance management (listed below) were published by Arizona WERA-060 participants since the last reporting period. Scott Nissen, Weed Scientist, Colorado State University, discussed a newly discovered resistance mechanism in higher plants. Dr. Todd Gaines, a recent graduate of the Weed Science program at Colorado State University, worked with glyphosate resistant Palmer amaranth that was recently discovered in a glyphosate-tolerant cotton field in Georgia by Dr. Stanley Culpepper. Dr. Culpepper and has team of university and USDA researchers determined that resistance was not the result of altered glyphosate absorption, translocation or metabolism. Dr. Gaines evaluated several other possible resistance mechanisms at the molecular level and determined that glyphosate resistance was due to a significant increase in EPSPS number. EPSPS is the target site for glyphosate. This increased copy number resulted in higher levels of the target enzyme, which conferred a high level of resistance in Palmer amaranth. Gene amplification has been found to confer resistance in insects, but has never been report in plants. Dr. Gaines was advised by Dr. Phil Westra, Weed Scientist, Colorado State University. Group discussion: The group had an in depth discussion relating to industry policies on the use of transgenic seeds for research purposes and the limitations that researchers face in using these products for developing sound resistance management principles. Suggestions were made that were passed on to industry contacts. Plans for upcoming meetings and activities also were discussed. Mark Whalon (Michigan State University) was elected chair. The 2010 meeting will be in Michigan.

The pink bollworm (PBW) eradication program is in full swing in Arizona and appears to be quite successful so far. In 2008 zero grower sprays for PBW were reported and 98.25% of upland cotton planted was Bt varieties. According to Dr. Tabashniks lab, no PBW resistance alleles have been detected either through PCR or conventional bioassays. Recent work in Arizona has helped to harmonize 2 apparently contradictory datasets regarding resistance to pyroproxifen. Evaluations conducted by Dr. Dennehys and now Dr. Lis lab indicate the development of resistance to pyroproxifen among native whiteflies. However, Dr. Ellsworths detailed examination of field performance through precision field-based bioassays have been unable to detect any performance loss in Arizona. Modeling and empirical results with a resistant strain of whiteflies by Dr. Crowder has shown the dynamics of resistance over time and in comparison to apparent changes to field densities. These data suggest that an incipient and growing level of resistance to pyriproxyfen can occur simultaneous with rather small, and perhaps undetectable, changes in seasonal, maximal whitefly densities. At present, pyriproxyfen is used on less than 15% of the cotton acreage in Arizona. Stakeholder need has been identified and a goal set to update and advance the cross-commodity management guidelines to incorporate new chemistries for whitefly control, including the diamides and the ketoenols. Development of cockroach resistance monitoring and management programs for indoxacarb gel baits (FL). Identification of negative cross-resistance factors in mosquitoes and other dipterans (FL). Development of molecular (RNAi-based) pesticides for management of resistance to conventional chemical pesticides (FL). Housefly insecticide resistance monitoring statewide and Florida dairies. Insecticide resistance monitoring and development of resistance management strategies for chinch bugs in Florida turf. Development of proactive resistance management strategies for invasive chili thrips in Florida. Routine monitoring of European corn borer populations at diagnostic concentrations have indicated that this target pest species of transgenic maize remains susceptible to Cry1Ab and Cry1F toxins. Laboratory selections for resistance to both Cry1F and Cry1Ab in European corn borer have resulted in significant levels of resistance. Additional strains from field populations have been identified and are currently being characterized with regard to inheritance, fitness, and biochemical basis of resistance. Experiments have been initiated to document the ability of Bt resistant European corn borer strains to utilize transgenic plant tissues. Preliminary results indicate that although survival is significantly reduced, it appears that development of the resistant strains on transgenic plants is possible. The genes for putative Bt toxin receptors are being cloned and sequenced and immunohistochemical localization of receptors has been initiated. For western corn rootworms, we have identified a specific resistance associated mutation for cyclodiene resistance that we will use to further our understanding of the population genetics and invasiveness of this species. Studied have been initiated to utilize RNA interference assays to assess gene function and identify potential target sites for novel control strategies

Publications: Alves, A.P., W.J. Allgeier, and B.D. Siegfried. 2008. Effects of the synergist S,S,S  tributyl phosphorotrithioate on indoxacarb toxicity and metabolism in the European corn borer, Ostrinia nubilalis (Hübner). Pestic. Biochem. Physiol 90: 2630. Buss, E. A. 2008. Biological control in the landscape. Florida Pest Pro Magazine 4 (4): 16-19. Buss, E. A. and P. Ruppert. 2008. Southern chinch bug management, 2007. Arthropod Pest Management Tests, vol. 33: 1 pg. Buss, E. A. and P. Ruppert. 2008. Southern chinch bug field trial, 2007. Arthropod Pest Management Tests, vol. 33: 1 pg. Chaskopoulou, A., S.N. Nguyen, R.M. Pereira, M.E. Scharf and P.G. Koehler. 2009. Toxicities of 31 volatile low molecular weight compounds against Aedes aegypti and Culex quinquefasciatus. Journal of Medical Entomology 46: 328-334. Crespo, A.L.B., T.A. Spencer, E. Nekl, and B.D. Siegfried. 2008. Comparison and validation of methods to quantify Cry1Ab from Bacillus thuringiensis for standardization of insect bioassays. Appl. Environ. Microbiol. 74: 130-135. Gaines, T., W. B. Henry, P. D. Byrn, P. Westra, S. J. Nissen, and D. L. Shaner. 2008. Jointed Goatgrass (Aegilops cylindrical) by Imidazolinone-Resistant Wheat Hybridization Under Field Conditions. Weed Science. 56:32-36. Hutchison, W.D., E.C. Burkness, S.J. Fleischer, et al. (2007-present). ZEA-MAP and PestWatch for Corn Earworm IRM and Moth Flight Mapping in North America: A Private-Sector, Public Partnership. On-line: http://www.vegedge.umn.edu/ZeaMap/zeamap.htm Hutchison, W.D., E.C. Burkness, B. Jensen, B.R. Leonard, J. Temple, D.R. Cook, R.A. Weinzierl, R.E. Foster, T.L. Rabaey, and B.R. Flood. 2007. Evidence for decreasing Helicoverpa zea susceptibility to pyrethroid insecticides in the Midwestern U.S. Plant Health Progress. (doi:10.1094/PHP-2007-0719-02-RV), On-line: http://www.plantmanagementnetwork.org/pub/php/symposium/hzea/ Magalhaes, L.C., B.W. French, T.E. Hunt, and B.D. Siegfried. 2008. Development of methods to evaluate susceptibility of soybean aphid to imidacloprid and thiamethoxam at lethal and sublethal concentrations. Entomol. Exp. Appl. 128: 330-336. Meihls, L.N., M. L. Higdon, B.D. Siegfried, N.J. Miller, T.W. Sappington, M.R. Ellersieck, T.A. Spencer, and B.E. Hibbard. 2008. Rapid evolution of resistance to Bt corn by western corn rootworm: evidence for multiple resistance mechanisms? Proc. Nat. Acad. Sci. 49: 19177-19182. Nowatzki, T.M., S.A. Lefko, R.R. Binning, S.D. Thompson, T.A. Spencer, and B.D. Siegfried. 2008. Validation of a novel resistance monitoring technique for corn rootworm (Coleoptera: Chrysomelidae) and Event DAS-59122-7 maize. J. Appl. Entomol. 132: 177-188. Pereira, E.J.G., N.P. Storer, and B.D. Siegfried. Inheritance of Cry1F resistance in laboratory-selected European corn borer and its survival on transgenic corn expressing the Cry1F toxin. Bull. Entomol. Research (doi:10.1017/S0007485308005920). Pereira, E.J.G., B.A. Lang, N.P. Storer, and B.D. Siegfried. 2008. Selection for Cry1F resistance in the European corn borer and cross resistance to other Cry toxins. Entomol. Exper. Appl. 126: 115-121. Song, C. and M.E. Scharf. 2009. Mitochondrial impacts of insecticidal formate esters in insecticide resistant and susceptible Drosophila melanogaster. Pest Management Science 65: 697-703. Song, C. and M.E. Scharf. 2008. Formic acid: a neurologically-active, hydrolyzed metabolite of insecticidal formate esters. Pesticide Biochemistry and Physiology 92: 77-82. Song, C. and M.E. Scharf. 2008. Neurological disruption by low molecular weight compounds from the heterobicyclic and formate ester classes. Pesticide Biochemistry and Physiology 92: 92-100. Seyran, M., Stevenson, K. L., and Brenneman, T. B. 2008. Baseline sensitivity of Fusicladium effusum to azoxystrobin and in vitro toxicity of the alternative oxidase inhibitor, salicylhydroxamic acid (SHAM). Phytopathology 98:S144. Seyran, M., Stevenson, K. L., and Brenneman, T. B. 2008. Baseline sensitivity of Fusicladium effusum to thiophanate-methol, dodine, fentin hydroxide, and propiconazole using a microtiter plate assay. Phytopathology 98:S212. Stevenson, K. L., Langston, D. B. Jr., and Sanders, F. H. 2008. Baseline sensitivity and evidence of resistance to boscalid in Didymella bryoniae. Phytopathology 98:S151. Stevenson, K., Seyran, M., and Brenneman, T. 2008. University of Georgia Pecan Scab Fungicide Resistance Monitoring Project. The Pecan Grower 20(1):46-47. Woodward, J. E., Brenneman, T. B., Kemerait, R. C. Jr., Smith, N. B., Culbreath, A. K., and Stevenson, K. L. 2008. Use of resistant cultivars and reduced fungicide programs to manage peanut diseases in irrigated and nonirrigated fields. Plant Dis. 92:896-902. Wyenandt, A., Maxwell, N. and D. Ward. 2008. Fungicide programs affect 'practical' resistance development in cucurbit powdery mildew of pumpkin. HortScience. 43:1838-1845. Wyenandt, C.A., Everts, K.E., Mulrooney, R.L., and S.L. Rideout. 2008. Developing a fungicide resistance management guide for vegetable crops grown in the mid-Atlantic region. Phytopathology 98:S173. Zhou, X., M.M. Wheeler, F.M. Oi and M.E. Scharf. 2008. RNA interference in the termite R. flavipes through ingestion of double-stranded RNA. Insect Biochemistry and Molecular Biology 38: 805-815. Presentations: Ellsworth, P. Lygus Management: A Western Perspective. Presented by invitation at the Open Forum - Management of the Sucking Bug Complex across the Cotton Belt, 2008 Beltwide Cotton Conferences, Nashville, Tennessee. January 9, 2008. URL: http://ag.arizona.edu/crops/presentations/08Nashville_Western_Lygus_vFlo.pdf Ellsworth, P.C., A. Fournier and T.D. Smith. 2007 (rev. 9/08). Based on Ellsworth, P.C. and J.S. Jones. 2000. Arizona Cotton Insect Losses. Publ. No. AZ1183. University of Arizona, College of Agriculture and Life Sciences, Cooperative Extension, Tucson, Arizona. URL: http://cals.arizona.edu/crops/cotton/insects/cil/cil.html Ellsworth, P.C. & S.E. Naranjo. 50 years of the Integrated Control Concept: Moving the Concept and Implementation forward in Arizona. North Carolina State University Department of Entomology seminar, Raleigh, NC. April 13, 2009. URL: http://ag.arizona.edu/crops/presentations/09IPM_NCSU_50-yrsvF16lo.pdf Ellsworth, P.C. & S.E. Naranjo. IPM in Arizona Cotton: Successful adoption of selective controls for multiple key insect pests. Presented at 6th International IPM Symposium, Portland, OR. March 26, 2009. URL: http://ag.arizona.edu/crops/presentations/09IPMPortlandBiorationalvF7lo.pdf Ellsworth, P., J. Palumbo, A. Fournier & Y. Carriere. Cross-commodity Insecticide usage: Spatial Analysis of Management Practices, Control & Risks. Presented at WERA-069 WesternIPM Coordinators Meeting, Chino Hot Springs, Alaska. May 20, 2008. URL: http://ag.arizona.edu/crops/presentations/SpatialX-commodityFlo.pdf Palumbo, J., Fournier and T.D. Smith. 2008. Arizona Vegetable Insect Losses. University of Arizona, College of Agriculture and Life Sciences, Cooperative Extension, Tucson, Arizona. URL: http://ag.arizona.edu/crops/vegetables/insects/vegiloss.html