|A506 Life Sciences Building - LSU
Baton Rouge, LA 70803
We communicate with our stakeholders using several methods as part of our program on invasive species and biological control. We cooperate closely with several federal, state, and local institutions working with invasive species management. Thanks to the LSU AgCenter Communications office we have developed websites, factsheets, webinars, short videos, and how-to manuals on invasive species. Graduate students in the laboratory participate actively in the development of non-technical communications as part of their career program.
For more information about outreach efforts, please visit our LSU AgCenter Invasive Species website.
Nutrients enhance the negative impact of an invasive floating plant on water quality and a submerged macrophyte
Wahl, C.F., Diaz, R., and Kaller, M. 2021. Journal of Aquatic Plant Management. In Press.
Adult cold tolerance and potential North American distribution of Myllocerus undecimpustulatus undatus (Coleoptera: Curculionidae)
Neal, A., Diaz, R., Qureshi, J. and Cave R. D. 2021. Biological Invasions. In Press: https://link.springer.com/article/10.1007/s10530-021-02601-9
Climate Mismatch Between Introduced Biological Control Agents and Their Invasive Host Plants: Improving Biological Control of Tropical Weeds in Temperate Regions
Harms, N., Knight, I., Pratt, P., Diaz, R. 2021. Insects. In Press: https://www.mdpi.com/2075-4450/12/6/549
Nutrients enhance the negative impact of an invasive floating plant on water quality and a submerged macrophyte
Wahl, C.F., Diaz, R., and Kaller, M. 2021. Journal of Aquatic Plant Management. In Press.
Invasive floating fern limits aerial colonization and alters community structure of aquatic insects
Wahl, C.F., Diaz, R., and Kaller, M. Wetlands. In Press: https://link.springer.com/article/10.1007/s13157-021-01457-y
Invasion of floating fern alters freshwater macroinvertebrate community structure with implications for bottom-up processes
Wahl, C.F., Kaller, M, and Diaz R. 2021. Hydrobiologia. In Press: https://link.springer.com/article/10.1007/s10750-021-04571-4
First report of dasheen mosaic virus infecting taro (Colocasia esculenta) in Louisiana
Escalante, C., Galo, D., Diaz, R. and Valverde, R. 2021. Plant Disease. In Press: https://doi.org/10.1094/PDIS-04-21-0854-PDN
Multiple Potential Stressors and Dieback of Phragmites australis in the Mississippi River Delta, USA: Implications for Restoration
Cronin, J. Johnson, J., and R. Diaz. 2020. Wetlands. DOI: 10.1007/s13157-020-01356-8
A review of the causes and consequences of geographical variability in weed biological control successes
Harms, N., J. Cronin, Diaz, R. and R. Winston. 2020. Biological Control. DOI: 10.1016/j.biocontrol.2020.104398
Investigating Plant Phenotype, Salinity, and Infestation by the Roseau Cane Scale as Factors in the Die-Back of Phragmites australis in the Mississippi River Delta, USA
Knight, I., J. Cronin, M. Gill, J. A. Nyman, B. Wilson, and R. Diaz. 2020. Wetlands. DOI: 10.1007/s13157-020-01307-3
Wahl,C., Diaz, R. and J. Ortiz. 2020. Aquatic Invasions In Press.
Wahl, C. and R. Diaz. 2020. Biocontrol Science and Technology 30: 569-580
Reid, M., Coetzee, J. A., Hill M. P., Diaz, R., Gettys, L. A., Cuda, J. P. and C. S. Reid. 2020. Florida Entomologist 103: 54-63.
Cozad, L. A., Diaz, R. and C. R. Mudge. 2019. Florida Entomologist 102:701-707.
Cozad, L. A., Mudge, C., and R. Diaz. 2019. Journal of Aquatic Plant Management 57: 62-68
Wahl, C.* and R. Diaz. 2019. Southeastern Naturalist 18: N41-N44.
Wang, Z., Chen, Y. and R. Diaz. 2019. Environmental Entomology 48: 641-648.
Cozad, A., Diaz, R. and C. Mudge. 2019. Biocontrol Science and Technology https://doi.org/10.1080/09583157.2019.1608512
Wang, Z., Chen, Y. and R. Diaz. 2019. Florida Entomologist 102: 181-186.
Wang, Z., Chen, Y., Diaz, R. and R. A. Laine. 2019. Journal of Insect Physiology 112: 1-8.
Wahl, C. , Mudge, C. and R. Diaz. 2018. Journal of Aquatic Plant Management 56: 113-119.
Knight, I., Wilson, B. E., Gill, M., Aviles, L., Cronin, J. T., Nyman, J. A., Schneider, S. A. and R. Diaz. 2018. Biological Invasions 10: 2739-2744.
Burckhardt, D., Cuda, J. P., Diaz, R., Overholt, W. A., Prade, P., Queiroz, D., Vitorino, M. D. and G. S. Wheeler, G. S. 2018. Florida Entomologist 101: 178-188.
Cozad, L. A., Harms, N., Russell, A. D., De Souza, M. and R. Diaz. 2018. Journal of Aquatic Plant Management 56: 1-12.
Smith. M., Overholt, W. A., Lake, E., Diaz, R., Manrique, M., Hight, S., Rohrig, E., Minteer, C., Wheeler, G., Rayamajhi, M., Bowers, K. and C. Kerr. 2018. Biocontrol Science and Technology 28: 293-306.
Battharai, G., Diaz, R., Manrique, V., Turechek, W., Buss, L., Stange, B. and W. A. Overholt. 2017. Biocontrol Science and Technology 27: 703-722.
Russell, A., Johnson, S., Cibils, X., McKay, F., Moshman, L., Madeira, P., Blair, Z. and R. Diaz. 2017. Biological Control 107: 41-49.
Comparative evaluation of development and reproductive capacity of two biotypes of Lilioceris cheni (Coleoptera: Chrysomelidae), Biological Control Agents of Air Potato (Dioscorea bulbifera) in Florida
Manrique, V., Lake, E. Smith, M., Diaz, R., Franko, C., Pratt, P. D., Rayamajhi, M. B. and W. Overholt. 2017. Annals of the Entomological Society of America 110: 310-316.
Wang, Z., Moshman, L., Kraus, E. C., Wilson, B. E., Acharya, N. and R. Diaz. 2016. Insects DOI: 10.3390/insects7040077
Wang, Z., Chen, Y., Gu, M. Vafaie, E., Merchant, M. and R. Diaz. 2016. Insects 7: 78. DOI: 10.3390/insects7040078
Prade, P., Diaz, R., Vitorino, M., Cuda, J. P., Kumar, P., Gruber, B. and W. A. Overholt. 2016. Biocontrol Science and Technology 26: 23-34.
Wheeler, G. S., McKay, F., Vitorino, M., Manrique, V., Diaz, R. and W. A. Overholt. 2016. Southeastern Naturalist 15(Sp8): 15-34.
Diaz, R., Romero, S., Roda, A. and W. A. Overholt. 2015. Florida Entomologist 98: 389-393.
Murrel, A. M., Pepper, A. E., Hodnett, G., Goolsby, J. A., Overholt, W. A., Racelis, A. E., Diaz, R. and P. E. Klein. 2015. Molecular Ecology 24: 2177-2193.
Diaz, R., Dickey, A., Shatters, R. G., Manrique, V., and Overholt, W. A. 2015. Florida Entomologist 28: 776-779.
Overholt, W., Diaz, R., Rosskopf, E., Green, S. J. and W. A. Overholt. 2015. PLoS ONE 10(7):e0132248. doi:10.1371/journal.pone.0132248
Diaz, R., Manrique, V., Munyaneza, J. E., Sengoda, V. G., Adkins, S., Hendricks, K., Roberts, P. and W. A. Overholt. 2014. Entomologia Experimentalis et Applicata 154: 1-14.
Stratman, K., Overholt, W. A., Cuda, J. P., Mukherjee, A., Diaz, R., Netherland, M. D., and Wilson, P.C. 2014. Journal of Insect Science 14: 1, 10.1093/jisesa/ieu015
Manrique, V., Diaz, R., Condon, T., and W. A. Overholt. 2014. BioControl 59: 761–770.
Diaz, R., Moscoso, D., Manrique, V., Williams, D. and W. A. Overholt. 2014. . Biocontrol Science and Technology 24: 536-553.
Diaz, R., Manrique, V., Hibbard, K., Fox, A., Roda, A., Gandolfo, D., McKay, F., Medal, J., Hight, S. and W. A. Overholt. 2014. Florida Entomologist 97: 179-190.
Manrique, V., Diaz, R., Erazo, L., Reddi, N., Wheeler, G. S., Williams, D. and W. A. Overholt. 2014. Biocontrol Science and Technology 24: 518-535.
Diaz, R., Menocal, O., Montemayor, C. and W. A. Overholt. 2013. Annals of the Entomological Society of America 106: 491-502.
Davis, D., Diaz, R. and W. A. Overholt. 2013. Journal of the Lepidopterists' Society 67: 35-41.
Manrique, V., Diaz, R., Montemayor, C., Serrano, D. and R. D. Cave. 2012. Annals of the Entomological Society of America 105: 854-864.
Diaz, R., Manrique, V., He, Z. and W. A. Overholt. 2012. Biocontrol Science and Technology 22: 763-776.
Mukherjee, A., Diaz, R., Thom, M., Overholt, W. A. and J.P. Cuda. 2012. Biocontrol Science and Technology 22: 447-461.
Manrique, V., Diaz, R., and W. A. Overholt. 2012. BioControl 57: 581-589.
Diaz, R., Hibbard, K., Samayoa, A. and W. A. Overholt. 2012. Florida Entomologist 9: 228-232.
Manrique V., Diaz, R., Pogue, M. G., Vitorino, M. D. and W. A. Overholt. 2012. . Biocontrol Science and Technology 22: 163-185.
Diaz, R., Aguirre, C., Wheeler, G. S., Lapointe, S. L. and W.A. Overholt. 2011. Environmental Entomology 40: 1437-1447.
Overholt, W.A., Diaz, R., Hanson, M. and D. Williams. 2011. Aquatics 33: 6-7.
Manrique, V., Diaz, R., Hight, S. and W.A. Overholt. 2011. Biological Control 59: 354-360.
Burckhardt, D., Cuda, J. P., Manrique, V., Diaz, R., Overholt, W. A., Williams, D. A., Christ, L. R. and M.D. Vitorino. 2011. Florida Entomologist 94: 489-499.
Manrique, V., Diaz, R., Cuda, J. P. and W.A. Overholt. 2011. Invasive Plant Science and Management 4: 1-10.
Overholt, W.A., Diaz, R., Markle, L. and J.C. Medal. 2010. Biocontrol Science and Technology 20: 791-807.
Reddy, R., Manrique, V., Diaz, R. and W. A. Overholt. 2010. Biocontrol Science and Technology 20: 997-1000.
Medal, J., Bustamante, N, Overholt, W., Diaz, R., Stansly, P., Roda, A., Amalin, D., Hibbard, K., Gaskalla, R., Sellers, B. and J.P. Cuda. 2010. Florida Entomologist 93: 130-132.
Diaz, R., Overholt, W. A., Heard, T. A., Samayoa, A. and R. D. van Klinken. 2010. Biological Control 55: 219-224.
Diaz, R., Overholt, W. A., Cuda, J., Pratt, P. and A. Fox. 2009. BioControl 54: 307-321.
Cave, R. C., Sciacchetano, C. and R. Diaz. 2009. Florida Entomologist 92: 578-581.
Overholt, W.A., Diaz, R., Hibbard, K., Roda, A., Amalin, D., Fox, A., Hight, S. D., Medal, J., Stansly, P., Carlisle, B., Walter, J., Hogue, P., Gary, L., Wiggens, L., Kirby, C. and S. Crawford. 2009. Florida Entomologist 92:450-457.
Diaz, R., Overholt, W. A., Cuda, J. P., Pratt, P. and A. Fox. 2008. Annals of the Entomological Society of America 101: 604-612.
Temperature-dependent development, cold tolerance, and potential distribution of Gratiana boliviana (Coleoptera: Chrysomelidae), a biological control agent of tropical soda apple, Solanum viarum (Solanaceae)
Diaz, R., Overholt, W. A., Samayoa, S., Sosa, F., Cordeau, D. and J. Medal. 2008. Biocontrol Science and Technology 18: 193-207.
Overholt, W. A., Diaz, R., Markle, L. and J. Medal. 2008. Florida Entomologist 91: 121-123.
Temperature-dependent development and potential distribution of Episimus utilis (Lepidoptera: Tortricidae), a candidate biological control agent of Brazilian peppertree (Sapindales: Anacardiaceae) in Florida
Manrique, V., Cuda, J. P., Overholt, W. A. and R. Diaz. 2008. Environmental Entomology 37: 862-870.
Sellers, B., Diaz, R., Overholt, W. A. and K. Langeland. 2008. Journal of the Aquatic Plant Management Society 46: 189-192.
Diaz, R., Samayoa, A., Overholt, W. A. and A. Pitty. 2008. CEIBA 49: 133-134.
Diaz, R., Overholt, W. A. and K. Langeland. 2008. Invasive Plant Science and Management 1: 422-425.
Diaz, R., Knutson, A. and J. Bernal 2004. Journal of Economic Entomology 97: 222-229.
Wiedenmann, R. N., Diaz, R. and C. Sadof. 2004. Journal of the Kansas Entomological Society 77: 99–109.
Overholt, W.A., Ewe, S. M. L., Diaz, R., Morgan, E. C. and O. E. Moeri. 2004. Florida Entomologist 87: 312–316.
Alleyne, M., Wiedenmann, R. N. and R. Diaz. 2001. Journal of Insect Physiology 47: 1419-1427.
We study invasive species impact on managed and natural ecosystems
and consider biological control the cornerstone of invasive species management.
Our laboratory is involved in research on invasive species which are in different stages of the invasion process. We have worked on detection techniques adapted to the life history of a range of species including emerald ash borer, crape myrtle bark scale, and roseau cane scale. We document the distribution and dispersal mechanisms of invasive species using field surveys, remote sensing, and citizen science.
Sampling methodologies are implemented to assess the impact of invasive species and they vary a lot. For example, we use drones to measure the coverage of aquatic weeds, and record the changes in dissolved oxygen, leaf chlorophyll content and photosynthesis, plant metabolites, among others. Due to the large diversity of species, we had worked in different habitats such as coastal wetlands, freshwater marshes, roadside disturbed habitats, forests, and urban settings.
Working with invasive species involves direct cooperation with our stakeholders including land managers of state parks, homeowners, farmers, aquatic weed managers, foresters, scientists, plant health regulators, conservationists, among others.
IMPROVING BIOLOGICAL CONTROL
Biological control is the use of natural enemies to reduce pest populations. Our laboratory is actively involved in classical biological control which is the use of host-specific natural enemies from the native range of the pest. International cooperation is at the core of our efforts. We enjoy facilitating the explorations of natural enemies of pests in USA, as welll as traveling to the native range of the organisms to find natural enemies! Because some invasive species occur over large regions, we have developed collaborative projects with several institutions in Southeastern U.S.A.
A new challenge on classical biological control is the climatic mismatch between agents and pests. Specifically, we work with subtropical weeds that are invading temperate regions such as water hyacinth, alligatorweed, giant salvinia, and parrot feather. We seek to understand the underlying problems of poor population growth of agents in the laboratory and in the field. We explore variation in life-history traits of existing populations by measuring thermal limits of agents, and search for new populations with desirable traits in the native range. Other approaches include habitat manipution to enhance overwintering survival, increase releases efforts early in the growing season, and integration with other control tactics based on site conditions.
Understanding fortuitous biological control has been fascinating. We discovered three non-native parasitoids of the roseau cane scale, native weevils attacking parrot feather and a non-native delphacid associated with a dieback of elephant ear. In next few years, we will be studying the relevance of these findings from an applied perspective.
Courses offer the theory and practice of Invasive Species Ecology and Biological Control. Efforts are made to have guest lectures with specialists with practical experience on the subjects. Using current research projects in the laboratory, we involve the students in discussions about the challenges and opportunities of using biological control. In addition, class assignments or activities are focus on benefiting directly the student's career. For example, we develop experiments or do review articles aimed for peer-reviewed journals, practice developing scientific presentations and oral communication skills, and write outreach materials related to key research projects. One of the goals is to motivate the student to dig deeper into topics that mean something to them!
After habitat loss, the impact of invasive species is the next most important threat to natural and managed ecosystems. In this course, the student will learn a brief history on the discipline of invasion ecology including the writing by Charles Elton and other workers who provided the foundation of the discipline.
The invasion process includes the transport, establishment, spread and impact of an organism. In addition, the course will cover different approaches to the study of invasive species including models of spread, risk assessment, impact measurement; and to manage invasive species including regulation, prevention, eradication, and control. Each class will be composed of a short lecture covering the theory, study cases, and in-class problem-solving exercises. Guest speakers working on invasive species in Louisiana will be invited to cover specific topics and provide experiences and different perspectives. Having a solid understanding on the process of a biological invasion will help students in the development of effective management programs.
The course will consist of two 1.5-hour lectures and/or discussion per week. Lectures will provide the fundamental concepts of each topic outlined below. Guest lectures will provide examples of invasive species and their management in Louisiana. Discussions will be summaries of key papers on invasion biology and will be led by students.
Biological control is the use of natural enemies including predators, parasitoids, weed feeders and entomopathogens for the reduction of pest densities. This course will focus on the concepts of biological control of insects, mites and weeds in natural and managed ecosystems. The student will learn about the history of biological control including critical pest management programs that provided the foundation of the discipline. The biology and diversity of natural enemies will be presented.
The course will cover the implementation of biological control including the importation of natural enemies or classical biological control, the deliberate increase of natural enemies or augmentation biological control, and the preservation and enhancement of resources to favor natural enemies or conservation biological control. In addition, the students will learn about techniques to monitor and evaluate natural enemies, federal regulations and the importance of educating the stakeholders about biological control. Having a solid understanding of biological control will help students in the development of effective pest management programs.
The course will consist of two 1-hour lectures and one 2-hour laboratory or discussion per week. Lectures will provide the foundational concepts on each topic outlined in the course schedule below. Laboratories will consist on development of research project o discussions each week. Discussions will be summaries of review papers about biological control and will be led by students. There will be three assignments and a final term-paper.
Rodrigo leads the research program on biological control and invasive species.
Matthew received his Bachelor of Science from LSU in Biological Sciences with a marine science concentration. He oversees the organization and completion of surveys and collections of Phragmites in the Mississippi River Delta and in the surrounding areas of southeast Louisiana. This is accomplished in order to better determine the health of the Phragmites as well as the abundance of roseau cane scale insects.
Emilie Ann Eastman
Emilie Ann assists with Phragmites research, including field surveys in the Mississippi River Delta, colony maintenance, and lab processing of samples.In addition, she aids in research about the biological control of giant salvinia.
Ilgoo studies the phylogeny of the subfamily Cardiochilinae (Braconidae) which contains several parasitoid species of crop pests. In addition, Ilgoo assists with the identification of parasitoids of our projects.
Logan is completing his Masters degree in Biology from Eastern Illinois University, where he is looking at insect community dynamics in hazelnut agroecosystems. Logan will be maintaining the Giant Salvinia biocontrol project, ensuring the Salvinia weevil populations are healthy and available for harvest by state and local agencies
Hannah assists with the aquatic weed biocontrol program. Activities include sampling salvinia weevils and monitoring recovery of freshwater wetlands.
Fatima runs thermal ecology studies of Mexican rice borer (Eoreuma loftini), and assists with field and laboratory experiments.
Emily assists with sample processing including aquatic macroinvertebrates, salvinia weevils and roseau cane scale.
Korey has broad interests on conservation ecology in managed and natural systems. In partnership with the Coastal Wetlands Planning, Protection and Restoration Act (CWPPRA) and LSU AgCenter, Korey is responsible for managing the giant salvinia weevil mass-rearing operation and monitoring giant salvinia infestations across Southern Louisiana.
Keyla works with parasitoids of the roseau cane scale (Nipponaclerda biwakoensis), and assist with field and laboratory experiments.
Josh completed his Master’s of Science degree in Entomology at Michigan State University in 2020 where he identified the effects of heat waves on the interaction and development of potato plants, early blight, and the Colorado potato beetle. Josh will be studying the invasive Roseau cane scale and its role in the Phragmites “Roseau cane” die-off in the Mississippi River Delta.
Tanner studies the parasitoids of the roseau cane scale (Nipponaclerda biwakoensis) present in Louisiana. The three species, Astymachus lasallei, Neastymachus japonicus, and Boucekiella depressa, are potential biocontrol agents of the scale. Tanner received his master’s degree from the University of Georgia in 2020 studying insecticide resistance in sweetpotato whitefly, Bemisia tabaci.
Carlos studies the insect herbivores associated with Conyza spp. (Asteraceae) in the Southeastern United States.
Seth studied air potato beetle distribution in LA and MS, and the biology of the fortuitous biological control agent of parrotfeather.
Steven Woodley, PhD,
Steven worked on biological control of giant salvinia, specifically, on population dynamics and the impact of salinity on the salinia weevil.
Ian Knight, PhD, Postoctoral Associate
Ian managed the roseau cane scale project including field sampling, biological control, and host plant resistance projects.
Leslie Aviles, M. Sc.
Leslie studied the host range of the roseau cane scale and host plant resistance among Phragmites populations.
Giovana Matos, M. Sc.
Giovana studied the impact of commercial entomophatogens on the crapemyrtle bark scale and associated predators.
Balwinder Kaur, M. Sc.
Balwinder evaluated the establishment of parasitoids for the emerald ash borer.
Lori Moshman, M. Sc.
Lori measured the impact of row cover fabrics and crowding as methods to increase overwintering temperatures for salvinia weevils.
Zinan Wang, M. Sc.
Zinan studied the overwintering ecology of the crapemyrtle bark scale.
Alana Russell, M. Sc.
Alana compared the thermal ecology of the salvinia weevil from populations from Louisiana, Australia and Argentina.
Charlie Wahl, PhD
Charlie studied the impact of giant salvinia on macroinvertebrate communities in Louisiana.