Progress 10/01/19 to 09/30/20
Outputs
Target Audience:The primary audience for this project was row crop growers and their consultants. This audience was reached through numerous talks at extension meetings and through posting results on the Mississippi Crop Situation blog. A secondary audience was the scientific community. Oral presentations are given at entomological meetings and numerous refereed manuscripts were published during the course of this project. A third audience includes students that took the classes that I teach (graduate and undergraduate students) and student workers in my research program. Data from this project were incorporated into my formal and informal teaching to these students. Changes/Problems:
Nothing Reported
What opportunities for training and professional development has the project provided?Under this CRIS, 3 M.S. students conducted their graduate research. These students have taken graduate courses, attended scientific and grower meetings, as well as being mentored on research methods, analysis and presentation. Additionally, 3 undergraduate students were employed and received research experience by collecting field data, conducting bioassays and rearing insects. How have the results been disseminated to communities of interest?Research findings were shared with extension colleagues and incorporated into extension blogs and papers as appropriate. Presentations have been made at meetings for growers and crop consultants in Mississippi and at regional and national scientific meetings. What do you plan to do during the next reporting period to accomplish the goals?More studies are planned to build on the sweetpotato variety trial, wireworm and cucumber beetle monitoring and the resistance monitoring of bollworm and soybean looper. In addition, continued research for effective rearing methods of redbanded stink bug will be a priority if insects can be collected. Research will also be initiated to identify physical and chemical properties associated with sweetpotato resistance.
Impacts
What was accomplished under these goals?
The overall impact of this project is that the soybean industry (growers/regulators/crop protection industry/extension) has more complete knowledge of how insects are impacting soybean production nationally. Furthermore there is current information on the susceptibility of key pests to widely used insecticides, so any degradation in susceptibiltiy will be detected before resulting in field control failures. New management tools are being developed in sweetpotato and soybean that will potentially decrease the costs of insect management in these crops. Obj. 1: A trial was conducted during 2020 that compared pheromone trapping methodologies in field cages for their efficiency in trapping soybean looper moths. Large and small field cages at 2 densities comparing commercial lures, live females and a control were compared. Lures were more attractive to male moths than females. Higher density infestations typically caught more moths than lower density infestations, but a lower percentage of the moths released. A sweetpotato variety trial was continued from previous years, with the goal of identifying varieties/line that show more insect resistance. Data from the 2018 and 2019 growing seasons showed that 'Murasaki' and several breeder lines had less insect damage, but they also yielded less than most commercial varieties. Data from 2020 is not yet compiled. A new project for 2020 was developing a sampling protocol in soybean using a drone. A modified sweep net was attached to a drone to facilitate insect sampling. Correlations were made to standard manual sweep net and drop cloth sampling methods. Sweep net sampling with a drone in a pass up to 150 ft long is feasible and all pest insects were captured at some level, but generally at lower numbers than in a manual set of 25 sweeps. Correlations have not yet been analyzed to determine the potential of this tool for sampling the numerous insect pests found in southern soybean fields. Obj. 2: Research regarding insecticide efficacy and resistance levels were studied on sweetpotato insects, soybean looper, bollworm, and tarnished plant bug during 2020. For sweetpotato insects, research consisted of comparing currently registered insecticides for control Lepidoptera. For soybean looper, research focused on susceptibility to chlorantraniliprole, spinosad and methoxyfenozide. Populations were collected from numerous states and Puerto Rico and reared 2 or more generations until all assays could be performed. Assays were conducted to determine resistance levels compared to two laboratory colonies. While the Puerto Rico colony was resistant to everything, none of the other populations showed resistance to any of the insecticides. Bollworm research focused on susceptibility to transgenic Bt crops, chlorantraniliprole, and indoxacarb. Bollworm feeding damage was observed in transgenic Bt corn and cotton expressing multiple Cry genes at levels approaching the non-Bt varieties, but corn and cotton varieties expressing Vip3A had little to no bollworm injury. For monitoring resistance to diamides and oxadiazines, populations were collected from across the southeastern US and reared 2 or more generations until all assays could be performed. No populations showed resistance to these chemical classes. Tarnished plant bug is the target of numerous insecticide applications in cotton, so monitoring susceptibility to key insecticides is a priority. During 2020, tarnished plant bug susceptibilities to an experimental insecticide were monitored on multiple populations collected from throughout Mississippi. Obj. 3: Insect movement and population dynamics research was continued on bollworm and tobacco budworm, weekly monitoring pheromone traps placed across a 3-county area throughout the growing season. A second project was expanded to monitor wireworms and cucumber beetles in sweetpotatoes using several pheromone lures in addition to continuing wireworm monitoring throughout the year using a bait trap. Obj. 4: Adult redbanded stink bugs were collected to attempt to rear them.under laboratory conditions. A few eggs were laid and several eggs hatched, but none of these nymphs were successfully reared to adults. Colonies of tarnished plant bug, soybean looper, and bollworm were reared using established protocols to provide insects as a baseline for insecticide resistance and efficacy assays.
Publications
- Type:
Journal Articles
Status:
Awaiting Publication
Year Published:
2020
Citation:
Reisig, D. D., D. Cook, J. Greene, M. Caprio, J. Gore, F. Musser and F. Reay-Jones. 2020. Vertical and temporal distribution of Helicoverpa zea (Lepidoptera: Noctuidae) larvae in determinate and indeterminate soybean. Bull. Entomol. Res.(in press) https://doi.org/10.1017/S0007485320000619.
- Type:
Journal Articles
Status:
Published
Year Published:
2020
Citation:
Catchot, B., C. J. H. Anderson, J. Gore, R. Jackson, K. Rakshit, F. Musser and N. Krishnan. 2020. Novaluron prevents oogenesis and oviposition by inducing ultrastructural changes in ovarian tissue of young adult Lygus lineolaris. Pest Manag. Sci. 76(12): 4057-4063. https://doi.org/10.1002/ps.5960.
- Type:
Journal Articles
Status:
Published
Year Published:
2020
Citation:
Dorman, S. J., A. D. Gross, F. R. Musser, B. D. Catchot, R. H. Smith, D. D. Reisig, F. P. F. Reay-Jones, J. K. Greene, P. M. Roberts, and S. V. Taylor. 2020. Resistance monitoring to four insecticides and mechanisms of resistance in Lygus lineolaris Palisot de Beauvois (Hemiptera: Miridae) populations in southeastern USA cotton. Pest Manag. Sci. 76 (12): 3935-3944. https://doi.org/10.1002/ps.5940.
- Type:
Journal Articles
Status:
Published
Year Published:
2020
Citation:
Reisig, D. D., D. Cook, J. Greene, M. Caprio, J. Gore, F. Musser and F. Reay-Jones. 2020. Location of Helicoverpa zea (Lepidoptera: Noctuidae) larvae on different plant parts of determinate and indeterminate soybean. Bull. Entomol. Res. 110: 725-731 https://doi.org/10.1017/S0007485320000280.
- Type:
Journal Articles
Status:
Published
Year Published:
2020
Citation:
Bateman, N., A. L. Catchot, J. Gore, D. R. Cook, F. R. Musser and J. T. Irby. 2020. Effects of planting date for soybean growth, development, and yield in the southern USA. Agronomy 10:596. https://doi.org/10.3390/agronomy10040596 .
- Type:
Journal Articles
Status:
Published
Year Published:
2020
Citation:
Crow, W., J. Gore, A. L. Catchot, D. R. Cook, S. D. Stewart, N. J. Seiter, G. Studebaker, G. Lorenz, D. Kerns, S. Brown, M. M. Jones, F. Musser, and T. Towles. 2020. Termination of insecticide applications for tarnished plant bug (Hemiptera: Miridae) management in cotton. J. Cotton Sci. 24(1): 17-26. https://www.cotton.org/journal/2020-24/1/17.cfm
- Type:
Other
Status:
Published
Year Published:
2020
Citation:
Crow, W., A. Catchot, J. Gore, D. Cook, F. Musser, G. Lorenz, N. Bateman, B. Thrash. G. Studbaker, S. Brown, T. Towles, D. Kerns and S. Stewart. 2020. Terminating tarnished plant bug insecticide applications. MSU Extension Service Publ. 3457. https://extension.msstate.edu/sites/default/files/publications/publications/P3457_web.pdf.
- Type:
Journal Articles
Status:
Published
Year Published:
2020
Citation:
Bateman, N. R., G. M. Lorenz, B. C. Thrash, J. Gore, M. O. Way, B. E. Wilson, L. A. Espino and F. R. Musser. 2020. 2017 Rice insect losses in the United States. Midsouth Entomol. 13: 24-32. http://midsouthentomologist.org.msstate.edu/.
- Type:
Journal Articles
Status:
Published
Year Published:
2020
Citation:
Musser, F. R., A. L. Catchot, Jr., S. P. Conley, J. A. Davis, C. DiFonzo, J. Greene, G. M. Lorenz, D. Owens, D. D. Reisig, P. Roberts, T. Royer, N. J. Seiter, R. Smith, S. D. Stewart, S. Taylor, K. Tilmon, R. T. Villanueva and M. O. Way. 2020. 2019 soybean insect losses in the United States. Midsouth Entomol. 13:1-23. http://midsouthentomologist.org.msstate.edu/.
|
Progress 10/01/18 to 09/30/19
Outputs
Target Audience:The primary audiencefor this project wasrow crop growers and their consultants. Thisaudiencewasreached through numerous talks at extension meetings and through posting results on the Mississippi Crop Situation blog. A secondary audience was the scientific community. Oral presentations are given at entomological meetings and numerous refereed manuscripts werepublished during the course of this project. A third audience includes students that tookthe classes that I teach (graduate and undergraduate students) and student workers in my research program. Data from this project were incorporated into my formal and informal teaching to these students. Changes/Problems:
Nothing Reported
What opportunities for training and professional development has the project provided?Under this CRIS, 2 M.S. studentsconducted their graduate research. These students have taken graduate courses, attended scientific and grower meetings, as well as being mentored on research methods, analysis and presentation. Additionally, 3 undergraduate students and 1 graduate student were employed and received research experience by collecting field data, conducting bioassays and rearing insects.. How have the results been disseminated to communities of interest?Research findings are shared with extension colleagues and incorporated into extension blogs and papers as appropriate. Presentations have been made at meetings for growers and crop consultants in Mississippi and at regional and national scientific meetings. What do you plan to do during the next reporting period to accomplish the goals?More studies are planned to build on the sweetpotato variety trial, wireworm and cucumber beetle monitoring and the resistance monitoring of bollworm and soybean looper. Assays will also be conducted to explore sub-lethal impacts of the experimental insecticide on tarnished plant bug. In addition, continued research for effective rearing methods of redbanded stink bug will be a priority if insects can be collected. Research will also be initiated to identify physical and chemical properties associated with sweetpotato resistance.
Impacts
What was accomplished under these goals?
Research was initiated or continued on management of several key insect pests of southern row crops. Obj. 1: A trial was conducted during 2019 that compared two trap designs and three commercial pheromone lures for their efficiency in trapping soybean looper moths. Both trap designs caught moths equally well, but the green bucket trap was easier to use than the delta trap with a sticky card. One of the commercial lures was inferior to the other 2, which were equal to each other. A sweetpotato variety trial was continued and expanded from previous years, with the goal of identifying varieties/line that show more insect resistance. Data from the 2018 growing season showed that 'Murasaki' and several breeder lines had less insect damage, but they also yielded less than most commercial varieties. Data from 2019 is not yet compiled. Obj. 2: Research regarding insecticide efficacy and resistance levels were studied on sweetpotato insects, soybean looper, bollworm, and tarnished plant bug during 2019. For sweetpotato insects, research consisted of comparing currently registered insecticides to a new active ingredient for control of the direct, underground stages of wireworms and cucumber beetles. For soybean looper, research focused on susceptibility to chlorantraniliprole, spinosad and methoxyfenozide. Populations were collected from Arkansas, Tennessee, Mississippi, Virginia, North Carolina, and South Carolina and reared for 2 generations. Assays were conducted to determine resistance levels compared to a laboratory colony. None of the populations showed high levels of resistance to any of the insecticides. Bollworm research focused on susceptibility to transgenic Bt crops and chlorantraniliprole. As reported in 2018, bollworm feeding damage was observed in transgenic Bt corn and cotton expressing multiple Cry genes at levels approaching the non-Bt varieties, but corn and cotton varieties expressing Vip3A had little to no bollworm injury. For monitoring resistance to diamides, vials coated with 20 ppm chlorantraniliprole were prepared and shipped to cooperators in the southern US between Virginia and Texas for testing with field-collected bollworm moths. This protocol was based on two years of lab and field testing which showed a high level of variability in populations. Results from 2019 assays have not been compiled. Questions remain as to how well bollworm adult susceptibility is correlated to larval susceptibility which is being addressed by David Kerns at Texas A&M. Tarnished plant bug is the target of numerous insecticide applications in cotton, so monitoring susceptibility to key insecticides is a priority. During 2019, tarnished plant bug susceptibilities to sulfoxaflor, imidacloprid and thiamethoxam and an experimental insecticide were monitored for the third year. Multiple populations from throughout Mississippi were successfully assayed for each insecticide. When combining all years of data, the range of susceptibility using LC50 estimates varied >60 fold for each of the commercially available insecticides. It is not known at this time how much of this variability is natural and how much is a result of selection for resistance. Research on the sub-lethal impacts of the insect growth regulator, novaluron, on adult tarnished plant bug were also continued. Previous electron micrographs of treated and untreated ovaries of newly emerged adults revealed that treatment reduced the production of yolk protein in the ovaries and compromised the integrity of immature eggs found in the ovaries. Novlauron treatment was applied to older females and the result was less visible changes in ovary development, which corresponds with previous research showing that exposure to older females does not impact egg production, but still reduces hatch rate. Obj. 3: Insect movement and population dynamics research was conducted on bollworm in Bt cotton, and wireworms and cucumber beetles in sweetpotatoes. The bollworm research compared movement of bollworm larvae when exposed to non-Bt, Bollgard 2, or Bollgard 3 cotton in field and lab settings. In the field trial, 3-day old larvae were placed in white flowers and vertical movement was recorded for several days. In the lab assay, neonate larvae were placed in the center of a petri dish containg leaf discs of all three cotton types. Every 24 hr, larval location and the amount of leaf feeding was recorded. In both assays, larvae moved away from both Bollgard 2 and Bollgard 3 tissues, indicating that larvae can sense the toxins before they ingest enough to kill them. There were not many differences between the response to Bollgard 2 and Bollgard 3 in these trials, likely due to using larvae from a lab colony. A new research project initiated during 2019 was monitoring wireworm and cucumber beetle larvae throughout the year. Bait (soaked wheat, corn and/or oats) was placed in a mesh bag and buried in a hole for a week. Unfortunately, no wireworm or larvae were collected at any time even though harvested sweetpotatoes at the end of the growing season showed evidence of populations. Obj. 4: Adult redbanded stink bugs were collected to attempt to rear them.under laboratory conditions. A few eggs were laid, but no insects developed from them, so little progress was made. Colonies of tarnished plant bug, tobacco thrips, soybean looper, bollworm and southern green stink bug continued to be reared using established protocols to provide insects as a baseline for insecticide resistance and efficacy assays.
Publications
- Type:
Journal Articles
Status:
Published
Year Published:
2019
Citation:
Olivi, B. M., J. Gore, F. R. Musser, A. L. Catchot, and D. R. Cook. 2019. Impact of simulated corn earworm (Lepidoptera: Noctuidae) kernel feeding on field corn yield. J. Econ. Entomol. 112(5) 2193-2198. https://doi.org/10.1093/jee/toz119
- Type:
Journal Articles
Status:
Published
Year Published:
2019
Citation:
Graham, S. H., F. Musser, A. L. Jacobson, A. Chitturi, B. Catchot and S. D. Stewart. 2019. Behavioral response of thrips (Thysanoptera: Thripidae) and tarnished plant bug (Hemiptera: Miridae) to a new Bt toxin, Bry 51Aa2.834_16 in cotton. J. Econ. Entomol. 112(4): 1695-1704. https://doi.org/10.1093/jee/toz058
- Type:
Conference Papers and Presentations
Status:
Published
Year Published:
2019
Citation:
Musser, F. R. and B. D. Catchot. 2019. Insecticide resistance monitoring: bollworms, loopers and tarnished plant bugs. In: Proc. Beltwide Cotton Conferences, New Orleans, LA, Jan. 8-10, 2019. National Cotton Council, Memphis, TN. Online: http://www.cotton.org/beltwide/proceedings.
- Type:
Other
Status:
Published
Year Published:
2019
Citation:
Reisig, D., D. Kerns, J. Gore and F. Musser. 2019. Managing pyrethroid- and Bt-resistant bollworm in southern U.S. cotton. Crops & Soils magazine Jan-Feb 2019, pp. 30-35. http://dx.doi.org/10.2134/cs2019.52.0108.
|
Progress 10/01/17 to 09/30/18
Outputs
Target Audience:The primary audiences for this project are row crop growers and their consultants. These audiences were reached through numerous talks at extension meetings and through posting results on the Mississippi Crop Situation blog. A secondary audience was the scientific community. Oral presentations are given at entomological meetings and numerous refereed manuscripts will be published during the course of this project. A third audience includes students that take the classes that I teach (graduate and undergraduate students) and student workers in my research program. Data from this project are incorporated into my formal and informal teaching to these students. Changes/Problems:
Nothing Reported
What opportunities for training and professional development has the project provided?Two graduate students worked under this project. These students have taken graduate courses, attended scientific and grower meetings, as well as being mentored individually on research methods,analysis, and presentation. Additionally, 3 undergraduate students have obtained significant research experience by collecting field data, conducting bioassays, and rearing insects. How have the results been disseminated to communities of interest?Research findings are shared with extension colleagues and incorporated into extension blogs and papers as appropriate. Presentations have been made at meetings for growers and crop consultants in Mississippi and at regional and national scientific meetings. What do you plan to do during the next reporting period to accomplish the goals?
Nothing Reported
Impacts
What was accomplished under these goals?
Research was initiated or continued on management of several key insect pests of southern row crops. Obj. 1: Action threshold research was conducted during 2017 on the wireworm-Diabrotica-Systena flea beetle (WDS) complex in sweet potato. Threshold research on the WDS complex was completed at two locations in Mississippi. An incorporated layby application and foliar applications using various thresholds were compared for insect damage on sweet potato on harvest dates ranging from 50- 120 days after transplanting. Adult insect pressure was primarily Diabrotica, but potato damage at harvest did not correspond to adult densities. Based on the size of the holes in the potato, most of the injury appears to be from wireworms, but few wireworm adults were observed at either location. A related trial conducted in 2017 and 2018 examined host plant resistance as a potential tool for sweet potato insect management. Several commercial varieties were compared to several lines received from breeders. The variety 'Murasaki' consistently had the least insect damage, but yields were also poor for this variety. 2018 data is not yet compiled. Obj. 2: Research regarding insecticide efficacy and resistance levels were studied on soybean looper, bollworm, and tarnished plant bug during 2018. For soybean looper, research focused on susceptibility to chlorantraniliprole, spinosad and methoxyfenozide. Populations were collected from Mississippi, Virginia, North Carolina and South Carolina and reared for 2 generations. Useable data from the North Carolina population could not be generated, but all other populations were similar to a laboratory colony in regards to susceptibility to all 3 insecticides. Bollworm research focused on susceptibility to transgenic Bt crops and chlorantraniliprole. Bollworm feeding damage was observed in transgenic Bt corn and cotton expressing multiple Cry genes at levels approaching the non-Bt varieties, but corn and cotton varieties expressing Vip3A had little to no bollworm injury. For monitoring resistance to diamides, research focused on developing a treated vial assay protocol to screen moths for resistance. This would be quicker and easier than traditional larval assays and would facilitate screening a large number of populations across the U.S. Vials can be prepared in advance and efficacy remains stable, even when kept under warm temperatures in light. Questions remain as to how well bollworm adult susceptibility is correlated to larval susceptibility. Tarnished plant bug is the target of numerous insecticide applications in cotton, so monitoring susceptibility to key insecticides is a priority. During 2018, tarnished plant bug susceptibility to sulfoxaflor, imidacloprid and thiamethoxam was monitored as initiated during 2017. At least eight populations from throughout Mississippi were successfully assayed for each insecticide. When combining both years of data, the range of susceptibility using LC50 estimates varied 60, 297, and 3133 fold for sulfoxaflor, imidacloprid, and thiamethoxam, respectively. It is not known at this time how much of this variability is natural and how much is a result of selection for resistance. Research on the sub-lethal impacts of the insect growth regulator, novaluron, on adult tarnished plant bug were also continued. Electron micrographs of treated and untreated ovaries revealed that treatment reduced the production of yolk protein in the ovaries and compromised the integrity of immature eggs found in the ovaries. This is most pronounced when females are exposed within 24 hr of adult emergence, but the viability of eggs is reduced within a few days of exposure, regardless of female age. The impact of a single exposure of novaluron on female fecundity and egg hatch rate persists throughout the life of the adult. Obj. 3: Pheromone trapping of bollworm and tobacco budworm continued as done previously in several counties in major agricultural production areas to understand population dynamics of these moths and to alert growers when major infestations should be anticipated. Obj. 4: Research was planned for developing a rearing system for redbanded stink bug. However, a colony was not available from the field, so no research on this area was performed during 2018. Colonies of tarnished plant bug, tobacco thrips, soybean looper, bollworm and southern green stink bug continued to be reared using established protocols to provide insects as a baseline for insecticide resistance and efficacy assays.
Publications
- Type:
Book Chapters
Status:
Published
Year Published:
2018
Citation:
Greene, J. K., J. A. Baum, E. P. Benson, C. S. Bundy, W. A. Jones, G. G. Kennedy, J. E. McPherson, F. R. Musser, F. P. F. Reay-Jones, M. D. Toews, and J. F. Walgenbach. 2018. General Insect Management. pp. 729-774. In: J. E. McPherson (ed.), Invasive Stink Bugs and Related Species (Pentatomoidea): Biology, Higher Systematics, Semiochemistry, and Management. CRC Press, Boca Raton, FL.
- Type:
Journal Articles
Status:
Awaiting Publication
Year Published:
2018
Citation:
North, J. J. Gore, A. Catchot, D. Cook, D. Dodds, and F. Musser. Quantifying the impact of excluding insecticide classes from cotton integrated pest management programs in the U.S. Mid-South. J. Econ. Entomol. https://doi.org/10.1093/jee/toy339
- Type:
Journal Articles
Status:
Awaiting Publication
Year Published:
2018
Citation:
Darnell-Crompton, C., A. Catchot, D. Cook, J. Gore, D. Dodds, S. Morsello and F. Musser. Neonicotinoid insecticide resistance in tobacco thrips (Thysanoptera: Thripidae) of Mississippi. J. Econ. Entomol. https://doi.org/10.1093/jee/toy298
- Type:
Journal Articles
Status:
Awaiting Publication
Year Published:
2018
Citation:
Etheridge, B., J. Gore, A. Catchot, D. Cook, F. Musser and E. Larson. Influence of temperature on the efficacy of foliar insecticide sprays against sugarcane aphid (Hemiptera: Aphididae) populations in grain sorghum. J. Econ. Entomol. https://doi.org/10.1093/jee/toy315
- Type:
Journal Articles
Status:
Published
Year Published:
2018
Citation:
Fleming, D., F. Musser, D. Reisig, J. Greene, S. Taylor, M. Parajulee, G. Lorenz, A. Catchot, J. Gore, D. Kerns, S. Stewart, D. Boykin, M. Caprio and N. Little. 2018. Effects of transgenic Bacillus thuringiensis cotton on heliothine counts, plant damage and cotton yield: a meta-analysis, 1996-2015. PLoS ONE 13(7): e0200131 https://doi.org/10.1371/journal.pone.0200131
- Type:
Journal Articles
Status:
Published
Year Published:
2018
Citation:
Bilbo T.R., F. P. F. Reay-Jones, D. D. Reisig, F. R. Musser, J. K. Greene. 2018. Effects of Bt corn on the development and fecundity of corn earworm (Lepidoptera: Noctuidae). J Econ Entomol. 111(5):2233-2241 https://doi.org/10.1093/jee/toy203.
- Type:
Journal Articles
Status:
Published
Year Published:
2018
Citation:
Bibb, J., D. Cook, A. Catchot, F. Musser, S. D. Stewart, B. R. Leonard, G. D. Buntin, D. Kerns, T. W. Allen and J. Gore. 2018. Impact of corn earworm (Lepidoptera: Noctuidae) on field corn (Poales: Poaceae) yield and grain quality. J. Econ. Entomol. 111(3): 1249-1255. https://doi.org/10.1093/jee/toy082
- Type:
Journal Articles
Status:
Published
Year Published:
2018
Citation:
North, J., J. Gore, A. Catchot, S. Stewart, G. Lorenz, F. Musser, D. Cook, D. Kerns, and D. Dodds. 2018. Value of neonicotinoid insecticide seed treatments in mid-south cotton (Gossypium hirsutum [Malvales: Malvaceae]) production systems. J. Econ. Entomol. 111(1): 10-15. https://doi.org/10.1093/jee/tox324
- Type:
Theses/Dissertations
Status:
Published
Year Published:
2018
Citation:
McRight, B. Evaluation of kudzu bug as a pest of Mississippi soybean production systems. M.S. thesis. Mississippi State University.
|
Progress 08/15/17 to 09/30/17
Outputs
Target Audience:The primary audiences for this project are row crop growers and their consultants. These audiences were reached through numerous talks at extension meetings and through posting results on the Mississippi Crop Situation blog. A secondary audience was the scientific community. Oral presentations are given at entomological meetings and numerous refereed manuscripts will be published during the course of this project. A third audience includes students that take the classes that I teach (graduate and undergraduate students) and student workers in my research program. Data from this project are incorporated into my formal and informal teaching to these students. Changes/Problems:
Nothing Reported
What opportunities for training and professional development has the project provided?Undergraduate students are employed to conduct the research which provides them an opportunity to learn about scientific inquiry in general and about specific insects and their behavior and management strategies. How have the results been disseminated to communities of interest?Research results are beingreported in extension and scientific meetings. What do you plan to do during the next reporting period to accomplish the goals?The kudzu bug research results are being written as a Master's thesis which should be completed and defended early in 2018. More studies are planned to build on the sweetpotato threshold and variety trials and the resistance monitoring of bollworm, soybean looper, and tarnished plant bug. In addition, continued research for effective rearing methods of redbanded stink bug will be a priority during 2018.
Impacts
What was accomplished under these goals?
Research was initiated or continued on management of several key insect pests of southern row crops. Obj. 1: Action threshold research was planned during 2017 on the wireworm-Diabrotica-Systena flea beetle (WDS) complex in sweet potato. Threshold research on the WDS complex was completed at two locations in Mississippi. An incorporated layby application and foliar applications using various thresholds were compared for insect damage on sweet potato on harvest dates ranging from 50- 120 days after transplanting. Adult insect pressure was primarily Diabrotica, and harvest data suggest that foliar applications were not effective in reducing insect damage to potatoes even though they suppressed adult densities. The layby application applied three weeks after transplanting however did reduce potato injury. Based on the size of the holes in the potato, most of the injury is believed to be from wireworms, but few wireworm adults were observed at either location. A related trial examined host plant resistance as a potential tool for sweet potato insect management. The variety 'Murasaki' consistently had the least insect damage (mainly from wireworm), but yields were also the poorest, so this variety may be a good candidate for breeder crosses, but is not commercially acceptable. More potential was found with 'Bayou Belle', which had the second least amount of insect damage and yielded as much or more than all other varieties. Obj. 2: Research regarding insecticide efficacy and resistance levels were studied on soybean looper, bollworm, tobacco budworm, tarnished plant bug, and kudzu bug during 2017. For soybean looper, research focused on susceptibility to chlorantraniliprole, a diamide insecticide. Two populations were collected and reared so the F1 generation could be tested. Both populations had levels of susceptibility similar to baseline levels established when diamides were introduced. Bollworm research was focused on susceptibility to transgenic Bt crops and chlorantraniliprole. Feeding damage was observed in transgenic Bt corn expressing Cry1A.105 and Cry 2Ab (VT2Pro). A collection was made and testing of the F1 generation revealed high levels of resistance to both genes. For resistance to diamides, research focused on developing a method to screen moths for resistance as simpler method of screening many populations. It is not clear if this assay method is feasible as results from the first year of research were variable. More research will continue to determine what factors can influence the results of this assay method. Pyrethroid screening of tobacco budworm moths was continued during 2017 as has been conducted for many years. Resistance to pyrethroids has been documented many times, but levels still vary, and this routine monitoring program documents the changes in susceptibility over time. Tarnished plant bug is the target of numerous insecticide applications in cotton, so monitoring susceptibility to key insecticides is a priority. During 2017 tarnished plant bug susceptibility to sulfoxaflor, imidacloprid and thiamethoxam was monitored. Seven or eight populations from throughout Mississippi were successfully assayed for each insecticide. The range from the lowest to highest estimated LC50 for a population was about 20-fold for imidacloprid and sulfoxaflor, and this likely represents natural variability among susceptible populations. However, susceptibility in thiamethoxam was varied by nearly 200-fold, so it is possible that some of these populations were demonstrating some resistance to thiamethoxam. Research on the sub-lethal impacts of the insect growth regulator, novaluron, on adult tarnished plant bug were also tested. Reduced egg hatch was previously documented in the laboratory, and we were able to demonstrate this from field applications during 2017, providing an explanation for the observed benefits of novaluron applications before nymphs are present. Obj. 3: Insect movement and dispersal were monitored during 2017 for tobacco thrips, and tarnished plant bug. Tobacco thrips densities were monitored in cotton and other nearby hosts weekly from early May until late June using Berlese funnels and sticky cards. Some species of thrips were found on every host sampled every week, but tobacco thrips were predominantly found on cotton, fleabane and young soybean. A comparison of counts on sticky cards placed immediately above the plant canopy vs. a meter above the canopy suggests that the proportion of short distance movement (thrips on low cards) varies over time and host, with long distance movement (high cards) most common when hosts are becoming less attractive to hosts later in the summer. Tarnished plant bug densities in cotton and nearby habitats were monitored weekly from late June through the end of August using sweep nets within a 4-mile diameter in Noxubee County, MS. Tarnished plant bugs were never numerous in any host except in horseweed when it was flowering. Nymphs were found only in horseweed, verbena and pigweed, suggesting that these hosts are likely most important for tarnished plant bug reproduction during mid-summer Obj. 4: Research was undertaken to develop a rearing system for redbanded stink bug. Numerous diet ingredients and environmental conditions have been tested to find a system where we can produce a reliable supply of redbanded stink bugs for research. To date, we have not been able to keep them alive for more than a few weeks, and oviposition and egg hatch has been minimal. At present we are focused on creating the correct environment to get survival and reproduction on living soybean plants. Once this is achieved, then we will work on the foods critical to its diet. In addition to this rearing research, colonies of tarnished plant bug, tobacco thrips, soybean looper, bollworm and southern green stink bug are being reared using established protocols to provide insects as a baseline for insecticide resistance and efficacy assays
Publications
- Type:
Journal Articles
Status:
Awaiting Publication
Year Published:
2018
Citation:
North, J., J. Gore, A. Catchot, S. Stewart, G. Lorenz, F. Musser, D. Cook, D. Kerns, B. R. Leonard and D. Dodds. Value of neonicotinoid insecticide seed treatments in mid-south corn (Zea mays) production systems. J. Econ. Entomol. https://doi.org/10.1093/jee/tox278
- Type:
Journal Articles
Status:
Published
Year Published:
2017
Citation:
Little, N., K. C. Allen, R. Luttrell, A. Catchot, F. Musser, J. Gore and D. Cook. 2017. Supplemental control with diamides for Heliothines in Bt cotton. Southwest. Entomol. 42(1): 15-26.
- Type:
Journal Articles
Status:
Published
Year Published:
2017
Citation:
Fleming, D., N. Krishnan and F. Musser. 2017. Polygalacturonase gene expression and enzymatic activity in salivary glands of laboratory reared and wild populations of Lygus lineolaris (Hemiptera: Miridae). Eur. J. Entomol. 114: 16-24. http://dx.doi.org/10.14411/eje.2017.003
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