2010 Annual Report
1a.Objectives (from AD-416)
Develop and refine boll weevil monitoring tactics to enhance suppression or eradication efforts. Develop improved and novel methods for elucidating the biology and ecology of southern green stink bugs. Improve current management strategies for cotton fleahopper through development of ecologically interpretable monitoring methods, elucidation of dispersal strategies in relation to the environment, and improved understanding of cotton fleahopper/cotton plant interactions. Identify and characterize neuropeptide hormones of arthropod pests and develop biostable, bioavailable mimics that can disrupt critical life processes to provide effective and environmentally sensitive pest control.
1b.Approach (from AD-416)
Studies will be conducted to investigate effects of diet on pheromone production by boll weevils, effects of the trap environment on boll weevil colonization patterns and captures in traps, and methods to locate and manage sources of weevil re-infestations. New methods will be developed to determine the reproductive/physiological development of southern green stink bugs and their utilization of wild host plants and crops. Dissections to identify reproductive/physiological characteristics and neuropeptide chemistry/biostable mimic technology will combine to reveal basic southern green stink bug biology and mechanisms for their behavior and ecology. This information will help determine the timing and approaches to manage southern green stink bug populations. Various pest sampling technologies and techniques will be evaluated relative to a reference sampling method in cotton to determine an efficient and effective sampling technology. Cotton fleahopper dispersal from uncultivated plants and colonization of early-season cotton fields will be determined relative to weather and physiological characteristics of the host plants. Plant stage-dependent feeding and oviposition activity, and consequent instar- or stage-dependent plant injury will be defined. Completion of the research will result in new sampling technologies and cotton fleahopper management guidelines. Knowledge of the role of neuropeptides will be developed which will lead to the development of neuropeptide mimics that resist degradation by enzymes in the digestive tract, hemolymph, and tissues. Research will be conducted to identify neuropeptides, and to develop and evaluate neuropeptide mimics that can regulate diuresis, ecdysis, diapause, and reproduction as tools to study the biology of sucking bugs and as pest insect management agents.
This is the final report for this project, which will be replaced by a new project beginning in FY 2011. Work over the five years of this project resulted in significant advances in understanding the biology and ecology of field crop insect pests, and in development of more effective methods for detecting, monitoring, and controlling important field crop pests in the U.S. We evaluated a boll weevil lure with a new blend of weevil pheromone at locations in Mexico and Texas where low-density populations of weevils persist; this work will establish if the new lure is more effective than the standard lure in detecting low-density populations of weevils, which will be critical in the post-eradication era. We identified unique physical characteristics of pollen grains of various cotton types; this information will help to identify likely sources of weevil re-infestations when different cotton types are grown within large regions. Work on the cotton fleahopper established that reliable population estimates can be obtained by sampling only the terminal portion of plants, regardless of the time of day when plants are sampled. Project work established which insecticides used in fleahopper control are least detrimental to populations of beneficial insects. Work using screened cages established the effects of plant canopy temperature and plant development on fleahopper populations; this work provided foundational information to support our efforts to definitively establish the relationship between cotton fleahopper density and plant damage under field conditions. We used a commercially available "electronic nose" to detect boll weevil pheromone and cotton bolls infected with the pathogen Pantoea agglomerans, a causative agent of South Carolina Boll Rot, a cotton disease in the southeastern U.S. Further refinement of this device should provide a rapid method for detecting the presence of boll rot in cotton fields. Project work established the spectral reflectance patterns of cotton plants and other row crops using ground-based sensors; our goal is to develop practical and reliable remote-sensing systems for areawide detection of regrowth and volunteer cotton plants. Presence of such plants dramatically impacts upon the Boll Weevil Eradication Program by serving as unrecognized (and thus untreated) host plants that sustain boll weevil populations and reduce Eradication Program progress. Project scientists developed a user-friendly guide to easily and rapidly identify six species of brown stink bugs that can infest cotton and other row crops; this guide is being productively used by crop consultants, extension personnel, and others to make informed decisions concerning control of these important crop pests. Neuropeptide hormones previously unknown to science were identified in the nervous system of stink bugs, flies, and ticks that regulate critical life processes. Many neuropeptide mimics were developed and tested by project scientists to identify candidates for new pest control agents that effectively control insects and ticks with great selectivity and in exceedingly small amounts.
Transmission of pathogenic microbes by the southern green stink bug. Southern green stink bugs (SGSB) are known to transmit a pathogenic bacterium (Pantoea agglomerans) to cotton bolls, resulting in sufficient boll damage to seriously affect fiber production and quality. ARS researchers at College Station, Texas, who conducted the earlier work, have now shown that the SGSB can acquire (by feeding) and retain in its system two other bacterial pathogens (Pantoea ananatis, Klebsiella pneumoniae) and a known pathogenic fungus (Nematospora coryli). However, only N. coryli was transmitted to cotton bolls by the infected insect. This work provides important new information in understanding the potential of the SGSB to damage crops not only by active feeding, but by transmitting plant diseases as well. The work is important in guiding the development of control strategies to minimize overall SGSB damage to a number of southern row crops.
Alternative hosts of the cotton fleahopper. The cotton fleahopper is an important insect pest of cotton that can live not only on cotton but on certain weedy plants as well. Knowing what these alternate hosts are is important in understanding the dynamics of fleahopper infestations in cotton and in developing effective, targeted control strategies. ARS researchers at College Station, Texas, cooperating with Texas A&M University colleagues, used a modern molecular biology technique (amplified fragment length polymorphism markers) to determine the genetic characteristics of fleahoppers collected from cotton and two weeds (horsemint, wooly croton). The fleahopper collections were made at several locations geographically isolated from each other and including wide variations in habitat type. The genetic analyses showed that in some locations, fleahopper populations living on weeds apparently did not contribute to cotton infestations. But in other locations they did. This work is important because it clearly shows that the cotton fleahopper exhibits different habits in different environments, and that monitoring protocols and control strategies for this pest, for maximum effectiveness, likely need to be specifically tailored to specific fleahopper populations and cotton production environments.
Hormones control water balance in the southern green stink bug. The southern green stink bug (SGSB) is an important pest in U.S. cotton, soybeans, and other crops; resistance of the insect to conventional insecticides used for its control is an ongoing concern. ARS researchers in College Station, Texas, in collaboration with British scientists, have established how neurohormones (small chains of amino acids) produced by the SGSB actively regulate the critical processes of water and mineral balance in the insect. The work involved several classes of neuropeptides and established important parameters for ongoing work to exploit neuropeptides in development of new technology to effectively and selectively control SGSB and other pest insects. The work is foundational to ongoing studies by project scientists and their international collaborators to develop versions of the natural neuropeptides that will be appropriate for environmentally sensitive control of pest insects and ticks, including the SGSB.
New aphicides based on neuropeptide hormone technology. Pest aphids cause hundreds of millions of dollars of crop damage every year, and many populations have already acquired resistance against the insecticides used for control. ARS researchers at College Station, Texas, in cooperation with British colleagues, developed an entirely new approach to the control of pest aphids. The technology is based on versions of natural aphid hormones (known as neuropeptides) that are modified in a manner such that they resist metabolism (inactivation) by natural aphid body enzymes. Natural neuropeptides in aphids and other insects regulate critical life processes such as water balance and digestion. Certain of the neuropeptide "mimics" developed by this work match or even exceed the potency of current insecticides used in aphid control. While the development of commercially viable neuropeptide technology for aphid control has not yet been realized, this accomplishment is foundational in moving the work forward, and in catalyzing interest and commitment to related work by other scientists in industry, academia, and government.
Spurgeon, D.W. and C.P.-C. Suh. 2009. Pheromone Production by the Boll Weevil (Coleoptera: Curculionidae) Fed Cotton Squares and Bolls. Journal of Entomological Science. 44:209-221.
Nachman, R.J., Pietrantonio, P.V. 2010. Interaction of mimetic analogs of insect kinin neuropeptides with arthropod receptors. In: Geary, T.G., Maule, A. G., editors. Neuropeptide Systems as Targets for Parasite and Pest Control. Austin, TX. Landes Bioscience. p. 86-98.
Esquivel, J.F. 2008. Observations and implications of the cotton fleahopper in Rapistrum rugosum. Journal of Entomological Science. 43:434-437.
Jones, G.D., Greenberg, S.M. 2009. Pollen contamination of boll weevil traps. Grana. 48:297-309.
Hallam, T.G., Raghaven, A., Kolli, H., Dimitrov, D.T., Federico, P., Qi, H., McCracken, G.F., Betke, M., Westbrook, J.K., Kennard, K., Kunz, T.H. 2009. Dense and sparse aggregations in complex motion: Video coupled with simulation modeling. Ecological Complexity. 7:69-75.
Esquivel, J.F., Esquivel, S.V. 2009. Identification of cotton fleahopper (Hemiptera: Miridae) host plants in Central Texas and compendium of reported hosts in the United States. Environmental Entomology. 38:766-780.
Esquivel, J.F. 2009. Stages of gonadal development of the southern green stink bug (Hemiptera: Pentatomidae): Improved visualization. Annals of the Entomological Society of America. 102:303-309.
Gillam, E.H., McCracken, G.F., Westbrook, J.K., Jensen, M.L., Balsley, B.B. 2009. Bats aloft: Variation in echolocation call structure at high altitudes. Behavioral Ecology-Sociobiology. 64:69-79.
Jones, G.D., Greenberg, S.M. 2009. Cotton pollen retention in boll weevils, a laboratory experiment. Palynology. 33:157-165.
Nachman, R.J., Ben-Aziz, O., Davidovitch, M., Kaczmarek, K., Zabrocki, J., Williams, H., Strey, A.A., Altstein, M. 2010. A novel dihydromidazoline trans-pro mimetic analog is a selective PK/PBAN agonist. Frontiers in Bioscience. E2:195-203.
Suh, C.P., Westbrook, J.K. 2010. Relationship between population estimates of cotton fleahoppers (Hemiptera: Miridae) obtained by terminal and whole plant examinations. Journal of Entomological Science. 45:1-7.
Esquivel, J.F., Anderson, R.M., Droleskey, R.E. 2009. A visual guide to identification of Euschistus spp. (Hemiptera: Pentatomidae) in central Texas. Southwestern Entomologist. 34:485-488.
Nachman, R.J. 2009. Trans-pro isosteres in the development of non-selective and selective mimetic insect pyrokinin neuropeptide agonists: A mini-review. Pestycydy/Pesticides. 14:33-39.
Neupert, S., Russell, W.K., Predel, R., Russell, D.H., Nachman, R.J. 2009. The neuropeptidomics of Ixodes scapularis synganglion. Journal of Proteomics. 72:1040-1045.
Neupert, S., Russell, W.K., Russell, D.H., Lopez, J., Predel, R., Nachman, R.J. 2010. Neuropeptides in Heteroptera: Identification of allatotropin-related peptide and tachykinin-related peptides using MALDI-TOF mass spectrometry. Peptides. 30:483-488.
Kim, K.S., Jones, G.D., Westbrook, J.K., Sappington, T.W. 2010. Multidisciplinary Fingerprints: Forensic Reconstruction of an Insect Reinvasion. Journal of the Royal Society Interface. 7(45):677-686.
Medrano, E.G., Esquivel, J.F., Bell, A.A., Greene, J., Roberts, P., Bachelor, J., Marois, J.J., Wright, D.L., Nichols, R.L., Lopez, J. 2009. Potential for Nezara virdula (Hemiptera: Pentatomidae) to transmit bacterial and fungal pathogens into cotton bolls. Current Microbiology. 59:405-412.
Greenberg, S.M., Jones, G.D., Adamczyk Jr, J.J., Setamou, M., Liu, T., Armstrong, J.S., Coleman, R.J., Eischen, F.A. 2009. Reproductive potential of field-collected overwintering boll weevils (Coleoptera: Curculionidae) fed on pollen in the laboratory. Insect Science. 16(4):321-327.
Coast, G.M., Tebrugge, V.A., Nachman, R.J., Lopez, J., Aldrich, J.R., Lange, A., Orchard, I. 2010. Neurohormones implicated in the control of Malpighian tubule secretion in plant sucking Heteropterans: The stink bugs Acrosternum hilare and Nezara viridula. Peptides. 31:468-473.
Smagghe, G., Mahdian, K., Zubrzak, P., Nachman, R.J. 2010. Antifeedant activity and high mortality in the pea aphid Acyrthosiphon pisum (Hemiptera: Aphidae) induced by biostable insect kinin analogs. Peptides. 31:498-505.
Hariton, A., Ben-Aziz, O., Davidovitch, M., Zubrzak, P., Nachman, R.J., Altstein, M. 2009. Bioavailabilty of beta-amino acid and C-terminally derived PK/PBAN analogs. Peptides. 30:2174-2181.
Lodyga-Chruschinska, E., Oldziej, S., Sanna, D., Micera, G., Chruscinski, L., Kaczmarek, K., Nachman, R.J., Zabrocki, J., Sykula, A. 2009. Coordination ability of insect kinin analogs. Polyhedron. 28:485-492.
Poels, J., Birse, R.T., Nachman, R.J., Fichna, J., Janecka, A., Vanden Broeck, J., Nassel, D.R. 2010. Characterization and distribution of NKD, a receptor for Drosophila tachykinin-related peptide 6. Peptides. 30:545-556.
Kunz, T.H., Gauthreaux, Jr., S.A., Hristov, N.I., Horn, J.W., Jones, G., Kalko, E.K., Kelly, T.A., Larkin, R.P., Mccracken, G.F., Swartz, S.M., Srygley, R.B., Dudley, R., Westbrook, J. K. and Wikelski, M. 2008. Aeroecology: Probing and Modeling the Aerosphere. Integrative and Comparative Biology. 48(1):1-11.
Pucci, T.M., Jones, G.D. 2010. Interspecific mouthpart length variation and floral visitation in the parasitic wasp genus Agathirsia (Braconidae: Agathidinae). Annals of the Entomological Society of America. 103:566-573.