Browsing by Author "Reisig, Dominic"

Now showing 1 - 4 of 4
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    Effects of transgenic Bacillus thuringiensis cotton on insecticide use, heliothine counts, plant damage, and cotton yield: A meta-analysis, 1996-2015
    Fleming, Daniel; Musser, Fred; Reisig, Dominic; Greene, Jeremy K.; Taylor, Sally V.; Parajulee, Megha; Lorenz, Gus; Catchot, Angus; Gore, Jeffrey; Kerns, David; Stewart, Scott; Boykin, Deborah; Caprio, Michael; Little, Nathan (PLOS, 2018-07-19)
    The primary management tactic for lepidopteran pests of cotton in the United States of America (USA) is the use of transgenic cotton that produces Bacillus thuringiensis Berliner (Bt) toxins. The primary target pests of this technology are Helicoverpa zea (Boddie) and Heliothis virescens (F.) in the eastern and central Cotton Belt of the USA. Concerns over the evolution of resistance in H. zea to Bt toxins and scrutiny of the necessity of Btcrops has escalated. We reviewed published and unpublished data from field trials of Btcotton in the eastern and central Cotton Belt of the USA through 2015 to evaluate the effectiveness of Bt cotton (Bollgard, Bollgard II, WideStrike, WideStrike 3, and TwinLink). Btcotton reduced insecticide usage, reduced heliothine pest numbers and damage, and provided a yield benefit, but Bollgard II and WideStrike efficacy declined in the Midsouth over the period evaluated. In the Southeastern region, heliothine damage remained constant through 2015, but yield benefits declined from 2010 until 2015. Resistance of H. zea to several Bttoxins is the most plausible explanation for the observed changes in Btcotton efficacy. The introduction of new Bttoxins such as found in Widestrike 3 and Twinlink may preserve the benefits of Bt crops. However, while both Widestrike 3 and Twinlink had less damage than Widestrike, damage levels of both were similar to Bollgard II.
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    Extended Sentinel Monitoring of Helicoverpa zea Resistance to Cry and Vip3Aa Toxins in Bt Sweet Corn: Assessing Changes in Phenotypic and Allele Frequencies of Resistance
    Dively, Galen P.; Kuhar, Tom P.; Taylor, Sally V.; Doughty, Helene; Holmstrom, Kristian; Gilrein, Daniel O.; Nault, Brian A.; Ingerson-Mahar, Joseph; Huseth, Anders; Reisig, Dominic; Fleischer, Shelby; Owens, David; Tilmon, Kelley; Reay-Jones, Francis; Porter, Pat; Smith, Jocelyn; Saguez, Julien; Wells, Jason; Congdon, Caitlin; Byker, Holly; Jensen, Bryan; DiFonzo, Chris; Hutchison, William D.; Burkness, Eric; Wright, Robert; Crossley, Michael; Darby, Heather; Bilbo, Tom; Seiter, Nicholas; Krupke, Christian; Abel, Craig; Coates, Brad S.; McManus, Bradley; Fuller, Billy; Bradshaw, Jeffrey; Peterson, Julie A.; Buntin, David; Paula-Moraes, Silvana; Kesheimer, Katelyn; Crow, Whitney; Gore, Jeffrey; Huang, Fangneng; Ludwick, Dalton C.; Raudenbush, Amy; Jimenez, Sebastian; Carrière, Yves; Elkner, Timothy; Hamby, Kelly (MDPI, 2023-06-25)
    Transgenic corn and cotton that produce Cry and Vip3Aa toxins derived from Bacillus thuringiensis (Bt) are widely planted in the United States to control lepidopteran pests. The sustainability of these Bt crops is threatened because the corn earworm/bollworm, Helicoverpa zea (Boddie), is evolving a resistance to these toxins. Using Bt sweet corn as a sentinel plant to monitor the evolution of resistance, collaborators established 146 trials in twenty-five states and five Canadian provinces during 2020–2022. The study evaluated overall changes in the phenotypic frequency of resistance (the ratio of larval densities in Bt ears relative to densities in non-Bt ears) in H. zea populations and the range of resistance allele frequencies for Cry1Ab and Vip3Aa. The results revealed a widespread resistance to Cry1Ab, Cry2Ab2, and Cry1A.105 Cry toxins, with higher numbers of larvae surviving in Bt ears than in non-Bt ears at many trial locations. Depending on assumptions about the inheritance of resistance, allele frequencies for Cry1Ab ranged from 0.465 (dominant resistance) to 0.995 (recessive resistance). Although Vip3Aa provided high control efficacy against H. zea, the results show a notable increase in ear damage and a number of surviving older larvae, particularly at southern locations. Assuming recessive resistance, the estimated resistance allele frequencies for Vip3Aa ranged from 0.115 in the Gulf states to 0.032 at more northern locations. These findings indicate that better resistance management practices are urgently needed to sustain efficacy the of corn and cotton that produce Vip3Aa.
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    Magnitude and Extent of Helicoverpa zea Resistance Levels to Cry1Ac and Cry2Ab2 across the Southeastern USA
    Reisig, Dominic; Buntin, G. David; Greene, Jeremy K.; Paula-Moraes, Silvana V.; Reay-Jones, Francis; Roberts, Phillip; Smith, Ron; Taylor, Sally V. (MDPI, 2023-03-07)
    After resistance is first detected, continued resistance monitoring can inform decisions on how to effectively manage resistant populations. We monitored for resistance to Cry1Ac (2018 and 2019) and Cry2Ab2 (2019) from southeastern USA populations of Helicoverpa zea. We collected larvae from various plant hosts, sib-mated the adults, and tested neonates using diet-overlay bioassays and compared them to susceptible populations for resistance estimates. We also compared LC50 values with larval survival, weight and larval inhibition at the highest dose tested using regression, and found that LC50 values were negatively correlated with survival for both proteins. Finally, we compared resistance rations between Cry1Ac and Cry2Ab2 during 2019. Some populations were resistant to Cry1Ac, and most were resistant to CryAb2; Cry1Ac resistance ratios were lower than Cry2Ab2 during 2019. Survival was positively correlated with larval weight inhibition for Cry2Ab. This contrasts with other studies in both the mid-southern and southeastern USA, where resistance to Cry1Ac, Cry1A.105, and Cry2Ab2 increased over time and was found in a majority of populations. This indicates that cotton expressing Cry proteins in the southeastern USA was at variable risk for damage in this region.
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    Soybean producers guide
    Vann, Rachel; Everman, Wesley; Holshouser, David L.; Huseth, Anders; Reisig, Dominic; Thiessen, Lindsey (U.S. Department of Agriculture Forest Service, Southern Research Station, 2021-11-01)
    This is 1 of 23 guides to help Southeastern U.S. producers of economically important agricultural commodities build resilience to, prepare for, and recover from hurricane impacts. All guides can be found on the USDA Southeast Climate Hub.