Source: UNIVERSITY OF CALIFORNIA, RIVERSIDE submitted to NRP
MINIMIZING THE NEGATIVE IMPACTS OF NEW INVASIVE SPECIES AND POLLUTANTS ON SUSTAINABLE CROP PRODUCTION IN CALIFORNIA
Sponsoring Institution
National Institute of Food and Agriculture
Project Status
COMPLETE
Funding Source
HATCH
Reporting Frequency
Annual
Accession No.
0207204
Grant No.
(N/A)
Cumulative Award Amt.
(N/A)
Proposal No.
(N/A)
Multistate No.
(N/A)
Project Start Date
Oct 1, 2011
Project End Date
Sep 30, 2016
Grant Year
(N/A)
Program Code
[(N/A)]- (N/A)
Recipient Organization
UNIVERSITY OF CALIFORNIA, RIVERSIDE
(N/A)
RIVERSIDE,CA 92521
Performing Department
Entomology, Riverside
Non Technical Summary
Until recently, sustainable low input IPM strategies for vegetable production had been widely adopted. However, these recent gains are at immediate risk because of the development of large populations of the potato psyllid and the losses associated with the transmission of a plant pathogen. The U.S. potato industry, a nearly $4 billion dollar crop in 2008, has been devastated by the appearance of this pathogen, known as 'zebra chip'. The insect and pathogen have spread to major production areas across the U.S. The losses are likely to increase as Korea, Argentina, and Brazil have established quarantine restrictions on U.S. potatoes. Tomato growers in Baja California, Mexico lost 85% of their tomatoes in 2001, and growers in San Diego Co, Ca lost 50% of their crops in 2003. In Ontario, Canada, greenhouse tomato growers experienced major losses. The potato psyllid was found in potato fields in Minnesota for the first time in 2007. A recent introduction into New Zealand has resulted in major losses in both peppers and tomatoes. Thus, the problem appears to be increasing in both geographic scope and economic importance. Using established procedures and novel strategies, we will develop new approaches to controlling the pest. These include 'green' approaches and plant resistance, as well as using chemistries selected for low mammalian and environmental toxicity. The benfits will be substantial. Consumers will be subjected to reduced potential pesticide residues on food, farm woirkers will be exposed to less pesticide residue, and growers will produce crops more economically, thus improving their profits. Finally, increased pesticide usage associated with psyllids and other new invasive pests, coupled with the use of ground water supplies contaminated with a variety of pollutants, have resulted in significant contamination of agricultural runoff water from fields. Very few studies have been conducted that investigate the effects of these pollutants on insects of importance in agriculture. Consider the example of selenium (Se). Se naturally enters the food chain through water and accumulates in drainage areas where evaporation concentrates soluble salts. Within the western USA, high Se levels around the Salton Sea and Kesterson National Wildlife Refuge have resulted in symptoms of Se intoxication of animals including lameness, hair loss, developmental retardation, malformation, and death. However these are not just localized problems; approximately 160,000 ha of agricultural land in the San Joaquin Valley of CA are affected by salinity and high water tables, a combination which has been correlated with high Se concentrations in this region. Unfortunately, very little is known regarding the effects of selenium accumulation in plants on the lower part of the food chain such as insects or how to deal sustainably with this problem. The effects are almost certainly greater on lower life forms than on mammals and avians. Additional studies designed to address these pollution problems are necessary to understanding both the impact of pollutants on agriculture and agriculture's effects on critical adjacent habitats.
Animal Health Component
(N/A)
Research Effort Categories
Basic
(N/A)
Applied
(N/A)
Developmental
(N/A)
Classification

Knowledge Area (KA)Subject of Investigation (SOI)Field of Science (FOS)Percent
1330320113010%
1330430113010%
2111499113010%
2151430113010%
2151460113010%
2161499113050%
Knowledge Area
133 - Pollution Prevention and Mitigation; 211 - Insects, Mites, and Other Arthropods Affecting Plants; 215 - Biological Control of Pests Affecting Plants; 216 - Integrated Pest Management Systems;

Subject Of Investigation
1499 - Vegetables, general/other; 1460 - Tomato; 0320 - Watersheds; 0430 - Climate; 1430 - Greens and leafy vegetables;

Field Of Science
1130 - Entomology and acarology;
Goals / Objectives
1. Epidemiological studies 1.1a Determine acquisition and inoculation access time required for potato psyllid to effectively transmit Ca, Liberibactor psyllarosus (CLp) to and induce disease in potato, tomato, and pepper plants 1.1b Conduct a survey of key weed/non-crop hosts supporting psyllids 1.1c Document if the weed/non-crop hosts in 1.1b also support Candidatus Liberibacter psyllaurous 2. Monitoring psyllid populations 2.1. Determine the within-plant preferences of psyllids at various stages of crop growth 2.2. Determine the within-field distributions of psyllids 2.3. From 2.1 and 2.2, create an efficient sampling strategy for psyllids 3. Development of an IPM program 3.1. Chemical strategies: 3.1a. Document any pesticide resistance development in populations of psyllids from Texas and California to at least the three most common chemical pesticides. 3.1b. Examine new green pesticides for control of the psyllid and determine economic viability of pesticide use strategies 3.1c. Examine pesticides for effects on the transmission of Ca. Liberibacter psyllaurous 3.2. Biological control strategies: 3.2a. Conduct a survey of natural enemies that attack the potato psyllid in California 3.3 Cultural control strategies: 3.3a. Characterize the amount of variation of Candidatus Liberibacter psyllaurous within and among populations of potato psyllid 3.3b. Determine if any of the most commonly planted cultivars of potatoes and peppers in CA provide significant resistance to the potato psyllid 3.4. Develop economically viable IPM strategies 4. Determine how key pollutants will influence plant-herbivore interactions in sustainable agriculture. Outputs: Research on the potato psyllid has allowed us to begin development of area-wide integrated pest management programs. We are investigating new chemistries, resistant plant varieties, and entirely novel new strategies for insect management. Presentations will be made to to scientific societies, growers, and others in California, the USA, and other countries. Publications will be placed in scientific journals and other outlets.
Project Methods
1.1a: After psyllid exposure, the insects will be removed from the test plants and then tested for CLp by qPCR to confirm infection. Statistical analyses will be conducted using ANOVA followed by an appropriate post-hoc test (SAS 2002). 1.1b. The percent of psyllids that are pathogen positive on various species of plants will be calculated. The data will be analyzed with PROC GLM in SAS. 1.1c. Host plants will be sampled from populations at different locations throughout California collected during the completion of objective 1.1b. The percentage data of plants within species containing Ca. Liberibacter psyllarous from each sample location and date will be analyzed with PROC GLM in SAS. 2.1.: Potatoes, tomatoes and peppers will be planted at university field stations in CA. Data and statistical analyses will follow the established protocols of Trumble (1982) and Shelton and Trumble (1990). 2.2. The within-field distributions will be calculated using the data collected in 2.1. Statistical analyses will follow the established procedures of Trumble (1994). 2.3. From 2.1 and 2.2, create an efficient sampling strategy for psyllids (after Brewer and Trumble 1991). Objective 3.1a. Document if the intensive use of imidacloprid, spinosad and spiromesifen has generated resistance. The insecticide LC50 values and the relevant 95% fiducial limits will be determined using Proc Probit procedure in SAS. Objective 3.1b. Costs and economic analyses of the programs will be determined using established techniques (Trumble 1998). Data analysis will be by ANOVA. Objective 3.1c Feeding bioassays will be conducted using methods similar to Liu and Trumble (2004). Behaviors will be analyzed between treatments with ANOVA. Objective 3.2a. Dynamics of natural enemies across time and space will be compared to the phenology of the psyllid in the crops and weeds. Objective 3.3a. Psyllids will be sampled from populations at different locations throughout California collected during the completion of objective 1.1a. Data will be analyzed with PROC GLM in SAS. Objective 3.3b.. This research will be conducted in cooperation with Dr. R. Novy of the USDA in Washington State and Dr. C. Miller at Texas A&M. Statistical analysis will be by ANOVA (see Liu et al. 2006). Objective 3.4. IPM programs will be field validated on the UC field stations. Economic analyses will be conducted using the procedures of Trumble (1998). 4. The influence of environmental pollutants on crop-herbivore relationships will be studied both in the laboratory and in the field. For studies with metalloids, initial research will focus on the the impact of plant accumulation of pollutants on pollination by honey bees. For water pollutants such as selenium, arsenic, and hexavalent chromium, plants will be grown in sand culture. All tests will be analyzed by ANOVA with appropriate transformations or typical non-parametric techniques. Studies on the changes in form and species of pollutants such as Se and arsenic as they move through crop plant and insect systems will be determined using commercial labs, the new spectrometer in Environmental Sciences, and with the Stanford Synchrotron (after Vickerman et al 2004).

Progress 10/01/11 to 09/30/16

Outputs
Target Audience:Target audiences include scientists and growers. Many presentations were were provided for growers and scientists in California, Idaho, Oregon, Utah, Illinois, and Washington, D.C. Trumble also participated in radio interviews (NPR) andnewspaper interviews. The pollution studies were reported in newspapers and radio. All of these presentations were designed to inform key people (scientists and growers) and to modify behaviors to help minimize problems. Changes/Problems: Nothing Reported What opportunities for training and professional development has the project provided?Deborah De La Riva, Ning Di, Kai Zhang and Marcus Pennington were graduate students in the Trumble lab. Issac Esquival, Christopher Tran, and Haley Drew were undergraduates being trained in various aspects of the research project. K. Hladun and S. Prager were post doctoral scientists in the Trumble lab and developed many new skills applicable across the STEM fields How have the results been disseminated to communities of interest?The primary outlet has been journal articles. We have also given numerous presentations to scientists, grower groups, beekeepers, and extension personnel. As part of the outrearch to lay people, Trumble has appeared in NPR news discussing the effects and control of the potato psyllid. What do you plan to do during the next reporting period to accomplish the goals? Nothing Reported

Impacts
What was accomplished under these goals? Epidemiological goals 1a, 1b, and 1c were largely accomplished and published in 2012, and monitoring and within plant distributions (objectives 2-2.1) were largely completed in 2013. Monitoring goals accomplished in 2014 included the development and publication of sequential sampling plans for psyllids on tomatoesthat varies with crop age and developmental stage. This complements our earlier sudies on sampling for psyllids in potatoes and bell peppers, which were published in the previous two reporting periods. In 2015 we completed studies on how the presence of other pathogens influence psyllid distribution and Zebra Chip transmission in tomatoes. Collectively, these studies are allowing the development of an area-wide approach to psyllid management. Development of an IPM program (goal 3) has continued, with the determination of additional resistance levels for neonicitinoids in California and Texas. This work has now been published and is permitting growers to select the most appropriate chemical control strategies for their regions. No additional studies on biocontrol agents were conducted since this goal was accomplished and published during the earlier reporting periods. We also completed and published a study on host plant preferences of psyllids and how this influences intercrop movements in 2016. Research on plant resistance is continuing even though we did characterize and publish the susceptibility and resistance levels of a variety of potato plant lines during the current reporting period. Some of these lines were promising enough that our cooperators in the USDA and at Texas A&M University are sending us additional plant lines for assessment. We have examined how key pollutants will influence social insects of economic importance (goal #4). In 2014-2017 hese studies included documentation (and publication) of effects of selenium on the surivival and development of an invasive species of ant that is causing millions of dollars in damage across the USA. We published extensively on the effects of pollutants (particularly metal contaminants) on honey bees and how phameceuticals in reclaimed water affect the development, survival and microbiome of a medically important mosquito.

Publications

  • Type: Journal Articles Status: Published Year Published: 2016 Citation: Hladun, K.R., N. Di, T.-X. Liu, and J.T. Trumble. 2016. Metal contaminant accumulation in the hive: consequences for whole colony health and brood production in the honey bee (Apis mellifera L.). Environmental Toxicology and Chemistry. 35: 322-329.
  • Type: Journal Articles Status: Published Year Published: 2016 Citation: Burden, C. M., C. Elmore, K. R. Hladun, J. T. Trumble, and B. H. Smith. 2016. Acute exposure to selenium disrupts associative conditioning and long-term memory recall in honey bees (Apis mellifera L.). Ecotoxicology and Environmental Safety 127: 7179.
  • Type: Journal Articles Status: Published Year Published: 2016 Citation: Pennington, M.J., S.M. Prager, W.E. Walton, and J.T. Trumble. 2016. (Culex quinquefasciatus) larval microbiomes vary with instar and exposure to common wastewater contaminants. Nature Scientific Reports 6:21969 | DOI: 10.1038/srep21969.
  • Type: Journal Articles Status: Published Year Published: 2016 Citation: Di, N., K. R. Hladun, K. Zhang, T.-X. Liu, and J. T. Trumble. 2016. Laboratory bioassays on the impact of cadmium, copper and lead on the development and survival of honeybee (Apis mellifera L.) larvae and foragers. Chemosphere 152: 530-538.
  • Type: Journal Articles Status: Published Year Published: 2016 Citation: De La Riva, D., and J. T. Trumble. 2016. Selenium exposure results in reduced reproduction in an invasive ant species and altered competitive behavior for a native ant species. Environmental Pollution 213: 888-894.
  • Type: Journal Articles Status: Published Year Published: 2016 Citation: Prager, S. M., G. Kund and J.T. Trumble. 2016. Low-input, low-cost IPM program helps manage potato psyllid. California Agriculture 70(2):89-95. DOI: 10.3733/ca.v070n02p89. April-June 2016.
  • Type: Journal Articles Status: Published Year Published: 2016 Citation: Wu, F., Y. Cen, C. Wallis, J. T. Trumble, S. Prager, R. Yokomi, Z. Zheng, X. Deng, J. Chen, G. Liang. 2016. The complete mitochondrial genome sequence of Bactericera cockerelli and comparison with three other Psylloidea species. PLOS ONE | DOI:10.1371/journal.pone.0155318.
  • Type: Journal Articles Status: Published Year Published: 2017 Citation: De La Riva, D. G., K. R. Haldun, B. G. Vindiola, and J. T. Trumble. 2017. Arthropod communities in a selenium-contaminated habitat with a focus on ant species. Environmental Pollution 220: 234-241.


Progress 10/01/14 to 09/30/15

Outputs
Target Audience: Target audiences include scientists and growers. Many presentations were were provided for growers and scientists in California, Idaho, Oregon, Utah, Illinois, and Washington, D.C. Trumble also participated in radio interviews (NPR) andnewspaper interviews. The pollution studies were reported in newspapers and radio. All of these presentations were designed to inform key people (scientists and growers) and to modify behaviors to help minimize problems. Changes/Problems: Nothing Reported What opportunities for training and professional development has the project provided? Deborah De La Riva, Ning Di, Kai Zhang and Marcus Pennington are graduate students in the Trumble lab. Issac Esquival, Christopher Tran, and Haley Drew were undergraduates being trained in various aspects of the research project. K. Hladun and S. Prager were post doctoral scientists in the Trumble lab and developed many new skills applicable across the STEM fields. How have the results been disseminated to communities of interest? Many presentations have been made to scientists, growers, and public interest groups. Scientific papers have been published on many of the the key objectives of the project. What do you plan to do during the next reporting period to accomplish the goals? This project will likely conclude in September of 2016. We are continuing our studies on the potato psyllid and its control, with the goal of developing a comprehensive IPM program. We are also completing studies on the effects of various metals and metalloids on plants and on honey bees and ants that feed/pollinate these plants. Additional research designedto document the effects of pollutants found in reclaimed water on economically and ecologically important insects is in progress and will likely continue for somer time.

Impacts
What was accomplished under these goals? Epidemiological goals 1a, 1b, and 1c were largely accomplished and published in 2012, and monitoring and within plant distributions (objectives 2-2.1) were largely completed in 2013. Monitoring goals accomplished in 2014 included the development and publication of sequential sampling plans for psyllids on tomatoesthat varies with crop age and developmental stage. This complements our earlier sudies on sampling for psyllids in potatoes and bell peppers, which were published in the previous two reporting periods. In 2015 we completed studies on how the presence of other pathogens influence psyllid distribution and Zebra Chip transmission in tomatoes. Collectively, these studies are allowing the development of an area-wide approach to psyllid management. Development of an IPM program (goal 3) has continued, with the determination of additional resistance levels for neonicitinoids in California and Texas. This work has now been published and is permitting growers to select the most appropriate chemical control strategies for their regions. No additional studies on biocontrol agents were conducted since this goal was accomplished and published during the earlier reporting periods. We also completed and published a study on host plant preferences of psyllids and how this influences intercrop movements. Research on plant resistance is continuing even though we did characterize and publish the susceptibility and resistance levels of a variety of potato plant lines during the current reporting period. Some of these lines were promising enough that our cooperators in the USDA and at Texas A&M University are sending us additional plant lines for assessment. We have examined how key pollutants will influence social insects of economic importance (goal #4). In 2014 hese studies included documentation (and publication) of effects of selenium on the surivival and development of an invasive species of ant that is causing millions of dollars in damage across the USA. In 2015 we published extensively on the effects of pollutants (particularly metal contaminants) on honey bees and how phameceuticals in reclaimed water affect the development, survival and microbiome of a medically important mosquito.

Publications

  • Type: Journal Articles Status: Published Year Published: 2015 Citation: Hladun, K.R., D. R. Parker, and J. T. Trumble. 2015. Cadmium, copper and lead accumulation and bioconcentration in the vegetative and reproductive organs of Raphanus sativus: Implications for plant function and pollination. Journal of Chemical Ecology DOI 10.1007/s10886-015-0569-7.
  • Type: Journal Articles Status: Published Year Published: 2015 Citation: Pennington, M. J., N. G. Rivas, S. M. Prager, W. E. Walton, and J. T. Trumble. 2015. Pharmaceuticals and personal care products alter the holobiome and development of a medically important mosquito. Environmental Pollution 203:199-207.
  • Type: Journal Articles Status: Published Year Published: 2015 Citation: Rubio-Covarrubias, O.A., M.A. Cadena-Hinojosa, R. Flores-L�pez, J.E. Munyaneza, S. M. Prager and J. T. Trumble. 2015. Assessing zebra chip resistance of advanced potato clones under field conditions in the Toluca valley, Mexico. Revista Latinoamericana de la Papa 19: 20-30
  • Type: Journal Articles Status: Published Year Published: 2015 Citation: Prager, S. M., C. Wallis, and J.T. Trumble. 2015. Indirect effects of one plant pathogen on the transmission of a second pathogen and the behavior of its potato psyllid vector. Environmental Entomology. http://dx.doi.org/10.1093/ee/nvv081
  • Type: Journal Articles Status: Published Year Published: 2015 Citation: Wu F, Deng X, Liang G, Wallis C, Trumble JT, Prager S, Chen J. 2015. De novo genome sequence of Candidatus Liberibacter solanacearum from a single potato psyllid in California. Genome Announc 3(6):e01500-15. doi:10.1128/genomeA.01500-15.
  • Type: Journal Articles Status: Published Year Published: 2016 Citation: Hladun, K.R., N. Di, T.-X. Liu, and J.T. Trumble. 2015. Metal contaminant accumulation in the hive: consequences for whole colony health and brood production in the honey bee (Apis mellifera L.). Environmental Toxicology and Chemistry. 10.1002/etc.3273


Progress 10/01/13 to 09/30/14

Outputs
Target Audience: Target audiences include scientists and growers. Many presentations were given to scientific groups during meetings in the USA,and Canada Many other presentations were provided for growers and scientists in California, Pennsylvania, Tennessee, Missouri and Texas. Trumble also participated in radio interviews (NPR) andnewspaper interviews. The pollution studies were reported on many websites, including Science Live. All of these presentations were designed to inform key people (scientists and growers) and to modify behaviors to help minimize problems. Changes/Problems: Nothing Reported What opportunities for training and professional development has the project provided? Deborah De La Riva and Marcus Pennington are graduate students in the Trumble lab. Issac Esquival, Christopher Tran, and Haley Drew were undergraduates being trained in various aspects of the research project. K. Hladun and S. Prager are post doctoral scientists in the Trumble lab and are developing many new skills applicable across the STEM fields. How have the results been disseminated to communities of interest? Many presentations have been made to scientists, growers, and public interest groups. Scientific papers have been published on many of the the key objectives of the project. What do you plan to do during the next reporting period to accomplish the goals? We are continuing our studies on the potato psyllid and its control. We are also completing studies on the effects of various metals and metalloids on plants and on honey bees and ants that feed/pollenate these plants. Additional research has begun on looking at the effects of pollutants found in reclaimed water on economically and ecologically important insects.

Impacts
What was accomplished under these goals? Epidemiological goals 1a, 1b, and 1c were largely accomplished and published in 2012, and monitoring and within plant distributions (objectives 2-2.1) were largely completed in 2013. Monitoring goals accomplished include the development and publication of a sequential sampling plan for psyllids on tomatoes that varies with crop age and developmental stage. This complements our earlier sudies on sampling for psyllids in potatoes and bell peppers, which were published in the previous two reporting periods. Collectively, these studies are allowing the development of an area-wide approach to psyllid management. Development of an IPM program (goal 3) has continued, with the determination of additional resistance levels for neonicitinoids in California and Texas. This work has now been published and is permitting growers to select the most appropriate chemical control strategies for their regions.No additional studies on biocontrol agents were conducted since this goal was accomplished and published during the earlier reporting periods. We also completed and published a study on host plant preferences of psyllids and how this influences intercrop movements. Research on plant resistance is continuing even though we did characterize and publish the susceptibility and resistance levels of a variety of potato plant lines during the current reporting period. Some of these lines were promising enough that our cooperators in the USDA and at Texas A&M University are sending us additional plant lines for assessment. We have examined how key pollutants will influence social insects of economic importance (goal #4). These studies included documentation (and publication) of effects of selenium on the surivival and development of an invasive species of ant that is causing millions of dollars in damage across the USA. Our other studies on the effects of metals on social insects are continuing.

Publications

  • Type: Journal Articles Status: Published Year Published: 2014 Citation: De La Riva, D. G., B. G. Vindiola, T. N. Casta�eda, D. R. Parker and J. T. Trumble. 2014. Impact of selenium on mortality, bioaccumulation and feeding deterrence in the invasive Argentine ant, Linepithema humile (Hymenoptera: Formicidae). Science of the Total Environment 481:446-452.
  • Type: Journal Articles Status: Published Year Published: 2014 Citation: Prager, S.M., C. D. Butler, and J. T. Trumble. 2014. A binomial sequential sampling plan for the psyllid Bactericera cockerelli Sulc (Hemiptera: Triozidae) in tomato (Solanum lycopersicum). Journal of Economic Entomology 107: 838-845.
  • Type: Journal Articles Status: Published Year Published: 2014 Citation: Arp, A, J. E. Munyaneza, J. M. Crosslin, J T. Trumble, and B. Bextine. 2014. A global comparison of Bactericera cockerelli (Hemiptera: Triozidae) microbial communities. Environmental Entomology 43: 344-352.
  • Type: Journal Articles Status: Published Year Published: 2014 Citation: Prager, S. M., I. Esquivel and J. T. Trumble. 2014. Factors influencing host plant choice performance in Bactericera cockerelli. PLoS ONE: 9(4): e94047. doi:10.1371/journal.
  • Type: Conference Papers and Presentations Status: Other Year Published: 2014 Citation: Trumble, J.T and K. Hladun. 2014. Metal pollutants and their impact on pollinators: Examining behavior, survival, and ecology. International Society of Chemical Ecology, Champaign IL
  • Type: Conference Papers and Presentations Status: Published Year Published: 2013 Citation: Prager, S. I. Esquivel, and J.T. Trumble. 2014. Patterns of host plant use in Bactericera cockerelli. Proc. of the 13th Annual Zebra Chip Reporting Session, San Antomnio TX. pp. 103-107.
  • Type: Conference Papers and Presentations Status: Published Year Published: 2013 Citation: Novy, R.G., S. Prager, J.C. Miller, B. Vindeola, and J.T. Trumble. 2013. Characterization of potato breeding clones to determine mechanisms confering observed resistance/tolerance to zebra chip disease. Proc. of the 13th Annual Zebra Chip Reporting Session, San Antomnio TX. pp. 38-42.
  • Type: Conference Papers and Presentations Status: Other Year Published: 2013 Citation: Hladun, K. and J.T. Trumble. 2013. From in vitro to field: Examining the toxic effects of soil-borne pollutants on honey bees. Entomological Society of America, Austin TX.
  • Type: Conference Papers and Presentations Status: Other Year Published: 2013 Citation: De La Riva, D., and J.T. Trumble. 2013. Consequences of chronic ingestion of a selenium-contaminated diet on the Argentine ant, Linepithema humile. Entomological Society of America, Austin TX.
  • Type: Conference Papers and Presentations Status: Other Year Published: 2014 Citation: Trumble, J. T. and C. Mogren. 2014. Overview of pollution effects on insect behaviors in aquatic systems and movement of arsenic between aquatic and terrestrial systems. International Society of Chemical Ecology, Champaign IL.
  • Type: Conference Papers and Presentations Status: Published Year Published: 2013 Citation: Prager, S., B. Vindeola, G. Kund, F.J. Byrne, and J. T. Trumble. 2013. An update on resiustance and the use of neonicatinoids to manage zebra chip and potato psyllids. 2013. Proc. of the 13th Annual Zebra Chip Reporting Session, San Antomnio TX. pp. 72-75.


Progress 01/01/13 to 09/30/13

Outputs
Target Audience: The target audiences for the research conducted in 2013 include growers, scientists, and undergraduate students. Specifically for growers, we presented talks to commodity boards such as the California Potato Board, the Califonia Pepper Commission, the California Celery Research Board, and the Annual Zebra Chip Reporting Session in San Antonio Texas. For scientists, we published numerous scientific papers, and made national and international presentations at meetings of the Entomological Society of America,the American Phytopathological Society, the Annual Meeting of the International Society of Chemical Ecology, a special meeting of the Western Region IPM Invasive species Working Group, and the California Department of Food and Agriculture. Undergraduate students, as well as post doctoral scientists were reached by training in the laboratory (internships for undergraduates) and through inclusion on research that resulted in their authorships on peer-reviewed publications. Changes/Problems: Nothing Reported What opportunities for training and professional development has the project provided? This project has provided training and opportunities for professional development at several levels. First, at least five undergraduate students have learned how to conduct research and data analysis. Several of these participates at a high enough level that they becamne co-authors on peer-reviewed publications. Second, several technicians received training in state-of-the-art scientific trechniques and were given the opportunitry to present their work at national scientific meetings. These technicians are also co-authors on many of our scientific, peer-reviewed publications. Third, three graduate students, including one that achieved their PhD in 2013, completed training in analytical analyses that include ICP-MS spectrophotometry of selenium, cadmium and lead. One completed and published research on micro-X-ray absorbtion spectroscopic analyses of arsenic localization and biotransformation within an insect, as well as trophic movements of arsenic from aquatic to terrestrial systems. All of these students gave numerous presentations and participated in grant writing and other academic activities critical for their career development. Fourth, a postdoctoral scientist was provided training (ICP-MS spectrophotometry, experimental design and data analyses)and professional development activities (presentations, grant writing) that resulted in a publications documenting effects of selenium accumulation on phytotoxicity herbivory and pollenation ecology of a key weed species. Because she developed critical data on honey bee mortalitty factors, her environmental work has been in considerable demand for national and international presentations. Finally, an Assistant Scientist(one step above post doctoral scientist)employed on the project has been given opportunities to learn grant writing skills critical to his career advancement, completed a series of studies on insecticide resistance management of a new pest and pathogen of potatoes, learned new analytical skills while developing and publishing binomial sequentrial sampling plans for insects, and given many presentations on all of these topics at national and international meetings. All of these individuals have learned necessary skills for collaborating with scientists across scientificdisciplinesand the skills needed for writing scientific presentations, reports to granting agencies, and transferring their data to diverse groups of interested parties including laymen, growers and scientists. How have the results been disseminated to communities of interest? Our research results have been transferred to scientists via many presentations at national and international scientific meetings. Our studies on selenium effects on honeybees and pollination ecology have been reported in numerous newspaper stories and online outlets, resulting in exposure to honey producers as well as the general public. Growers have been informed of our studies on agricultural pests through presentations and reports to commodity boards such as the California Potato Commission, the California Pepper Commission, and the California Celery Research Advisory Board. In addition, our extensive participation in the Annual Zebtra Chip Research Meetings has transferred information to growers, scientists and laymen interested in the introduction, epidemiology, sampling, and control of a new invasive species attacking potato crops in the western United States. Also, by participating in a documentary made by The Public Broadcast System (KQED Science video and NPR), our research describing the challanges of managing this invasive pest has reached many growers and members of the genreal public. This video is available online at KQED Science and on the Trumble lab website (http://faculty.ucr.edu/~john/Trumble.html). What do you plan to do during the next reporting period to accomplish the goals? We will continue to give presentations, generate research reports and produce publications that will educate scientists, growers and the general public about our reseach activities and results.

Impacts
What was accomplished under these goals? Epidemiological goals 1a, 1b, and 1c were largely accomplished and published in 2012, but we continued to sample weeds and potential non-crop hosts for psyllids and the associated pathogen during this reporting period. Monitoring goals accomplished include the development and publication of a sequential sampling plan for psyllids on bell peppers that vaies with crop age and developmental stage. This complements our earlier sudies on sampling for psyllids in potatoes, which was published in the previous reporting period. Considerable research on within-plant and within-field distributions of psyllids in tomatoes will result in a binomial sequential sampling plan in the next reporting period. Collectively, these studies are allowing the development of an area-wide approach to psyllid management. Development of an IPM program (goal 3) has continued, with the determination of current resistance levels for neonicitinoids in California and Texas. This work has now been published and is permitting growers to select the most appropriate chemical control strategies for their regions. Considerable work on using 'green chemistries' for psyllid control were accomplished and published during the last reporting period, but new studies of repellants and rotational stratiges were conducted during this reporting period. No additional studies on biocontrol agents were conducted since this goal was accomplished and published during the earlier reporting periods. Research on plant resistance is continuing even though we did characterize and publish the susceptibility and resistance levels of a variety of potato plant lines during the current reporting period. Some of these lines were promising enough that our cooperators in the USDA and at Texas A&M University are sending us additional plant lines for assessment. We have examined how key pollutants will influence plant-herbivore interactions in sustainable agriculture and in medically-important insects (goal #4). These studies included documentation (and publication) of effects of selenium accumulation on herbivory and pollination ecology in radish, the effects of selenium on development and survival of the honey bee, movement of arsenic from aquatic to terestrial habitats, distribution and fate of arsenic in insects, and how Bacillus thuringiensis will interact with arsenic to affect larval mosquito development in farm ponds and similar ecosystems.

Publications

  • Type: Journal Articles Status: Published Year Published: 2013 Citation: Prager, S.M., Vindiola, B., Kund, G.S., Byrne, F. J. and Trumble, J.T. 2013. Considerations for the use of neonicotinoid pesticides in management of Bactericera cockerelli (Sulk) (Hemiptera: Triozidae). Crop Protection 54: 84-91.
  • Type: Journal Articles Status: Published Year Published: 2013 Citation: Hladun, K.R., O. Kaftanoglu, D. Parker, K. Tran, and J. T. Trumble. 2013. Effects of selenium on development, survival and accumulation in the honey bee (Aphis mellifera L.). Environmental Toxicology and Chemistry 32: 2584-2592.
  • Type: Journal Articles Status: Published Year Published: 2013 Citation: Mogren, C.L., W.E. Walton, and J.T, Trumble. 2013. Tolerance to individual and joint effects of arsenic and Bacillus thuringiensis subsp. israelensis or Lysinibacillus sphaericus in Culex mosquitoes. Insect Science. DOI: 10.1111/1744-7917.12046.
  • Type: Journal Articles Status: Published Year Published: 2013 Citation: Diaz-Montano J., B. G. Vindiola, N. Drew, R. G. Novy, J. C. Miller Jr., and J. T. Trumble. 2013. Resistance of selected potato genotypes to the potato psyllid (Hemiptera: Triozidae). American Journal of Potato Research. DOI 10.1007/s12230-013-9356-6.
  • Type: Journal Articles Status: Published Year Published: 2013 Citation: Mogren, C.L., W. E. Walton, D. Parker, and J. T. Trumble. 2013. Trophic transfer as a route of arsenic movement from aquatic to terrestrial environments. PLOS ONE 8(6) e67817. doi:10.1371/journal.pone.0067817.
  • Type: Journal Articles Status: Published Year Published: 2013 Citation: Mogren, C. L., S. Webb, W.E. Walton and J.T. Trumble. 2013. Micro x-ray absorption spectroscopic analysis of arsenic localization and biotransformation in Chironomus riparius Meigen (Diptera: Chironomidae) and Culex tarsalis Coquillett (Culicidae). Environmental Pollution 180: 78-83.
  • Type: Journal Articles Status: Published Year Published: 2013 Citation: Prager, S. M. , C. D. Butler, and J. T. Trumble. 2013. A sequential binomial sampling plan for potato psyllid (Hemiptera: Triozidae) on bell pepper (Capsicum annum). Pest Management Science DOI: 10.1002/ps.3475.
  • Type: Conference Papers and Presentations Status: Published Year Published: 2013 Citation: Prager, S.M.. Esquivel, I. and Trumble, J.T. 2013. Patterns of host plant use in Bactericera cockerelli. 2013 SCRI Zebra Chip Annual Reporting Session, San Antonio TX. (Proceedings)
  • Type: Journal Articles Status: Published Year Published: 2013 Citation: Hladun, K. R., D. R. Parker, K. D. Tran, and J. T. Trumble. 2013. Effects of selenium accumulation on phytotoxicity, herbivory, and pollination ecology in radish (Raphanus sativus L.). Environmental Pollution 172: 70-75.
  • Type: Conference Papers and Presentations Status: Published Year Published: 2013 Citation: Prager, S.M. and Trumble, J.T. 2013. Status of Vegetable Pests in Southern California and Management of Pysllids on Solanaceous Vegetable Crops. 2013. Annual Meeting of the Entomological Society of America, Austin, TX (Abstract).
  • Type: Conference Papers and Presentations Status: Published Year Published: 2013 Citation: Novy, R.G., Prager, S.M. Miller, Jr., J.C., Vindeola, B. and J.T. Trumble. 2013. Characterization of potato breeding clones to determine mechanisms conferring observed resistance/ tolerance to zebra chip disease. 2013 SCRI Zebra Chip Annual Reporting Session, San Antonio TX. (Proceedings)
  • Type: Conference Papers and Presentations Status: Published Year Published: 2013 Citation: Trumble, J.T., Prager, S.M., Vindiola, B., Kund, G.S., Byrne, F. J. 2013. An update on resistance and use of neonicotinoids to manage zebra chip and potato psyllids. 2013 SCRI Zebra Chip Annual Reporting Session, San Antonio TX. (Proceedings)
  • Type: Conference Papers and Presentations Status: Published Year Published: 2013 Citation: Vindiola, B., Kund, G.S., Prager, S.M, and Trumble, J.T. 2013. Investigations of potato psyllid repellents. Annual Meeting of the Pacific Branch of the ESA. South Lake Tahoe, CA. (Abstract)


Progress 01/01/12 to 12/31/12

Outputs
OUTPUTS: We have completed a series of projects dealing with the invasive potato psyllid and the accumulation of the pollutant selenium in an weed species. The potato psyllid research has examined 1) the potential for biological control, 2) developed sampling programs for the psyllid that will help growers avoid unnecessary pesticide applications 3) investigated the repellency of some essential oils, and 4), determined the effects of common insecticides on a key parasite of psyllid nymphs. In addition we have examined the behavioral effects of chemicals on psyllids that demonstrate why some pesticides can reduce transmission of a key pathogen at levels that do not kill the psyllid. In other experiments, we have documented 1) the survival, reproduction, and arsenic body burdens in Chironomus riparius exposed to arsenate and phosphate, and 2) the effects of selenium on survival and behaviors of honey bees. The results of our work have been disseminated through publications, reports on PBS, numerous meetings with scientists and growers in California, Pennsylvania, Missouri, Tennessee, Texas, and Europe. Powerpoint reports have also been made available to growers at most these locations. This research has been presented to scientists at the Entomological Society of America, the Ecological Society of America, and many other outlets. PARTICIPANTS: C. Butler was PhD student in the Trumble lab. K. Hladun and S. Prager are post doctoral scientists in the Trumble lab. Undergraduates include Issac Esquival, Khoa Dang Vu Tran, Jessica May, Tracy Vendrell, and Nichole Drew are undergraduates being trained in various aspects of the research. D. Parker is a collaborator in the Environmental Sciences Department at UCR; T. Liu, and L. Peng are collaborators at Texas A&M University (now at The Northwest Agric and Forestry University in China); F. Byrne and K. Visscher are collaborators in the Department of Entomology at UCR; and Brian Smith and Julie Mustard are faculty at the Arizona State University. Partner groups include Texas Agrilife, The California Potato Commission, the California Pepper Commission, the US Potato Commission and the California Celery Research and Marketing Board. TARGET AUDIENCES: Target audiences include scientists and growers. Many presentations were given to scientific groups during meetings in the USA, South Korea, Lithuania, and France. Many other presentations were provided for growers and scientists in California, Pennsylvania, Tennessee, Missouri and Texas. Trumble also participated in radio interviews (NPR) and television interviews (PBS). The pollution studies were reported on many websites, including Science Live. All of these presentations were designed to inform key people (scientists and growers) and to modify behaviors to help minimize problems. PROJECT MODIFICATIONS: There have been no substantial changes in the research approach or rationale.

Impacts
The objectives of one study were to determine the repellency of essential oils to the potato psyllid. The results suggested that the inclusion of repellents into an IPM program for the psyllid would improve psyllid control and provide substantial economic benefit. In a second study we report on the the effects of beneficial insects on psyllid control. In our pollution studies, our main objective this year was to extend the previous results on accumulation of Se in two Brassicaceae species to determine if the levels sequestered would affect honey bee survival and behavior. The results were substantial, with major reductions in survival of both foragers and larvae, and substantial changes in critical behaviors of adult bees. This study provides crucial information about where some of the highest concentrations of Se are found in two phytoremediators, and may sheds light on the potential risks pollinators may face when foraging upon these accumulating plants. We also determined that arsenic, which is common in some streams on the west coast of the USA, is concentrating in bodies of some common midges. This work has implications for the transfer of arsenic to higher trophic levels.

Publications

  • Diaz-Montano, J. and J. T. Trumble. 2012. Behavioral Responses of the potato psyllid (Hemiptera: Triozidae) to volatiles from dimethyl disulfide and plant essential oils. Journal of Insect Behavior. DOI: 10.1007/s10905-012-9350-8.
  • Butler, C.D. and J. T . Trumble. 2012. Identification and impact of natural enemies of Bactericera cockerelli in southern California. Journal of Econiomic Entomology 105: 1509-1519.
  • Liu, T., Y. Zhang, L. Peng, P. Rojas,and J.T.Trumble. 2012. Risk Assessment of Selected Insecticides on Tamarixia triozae (Hymenoptera: Eulophidae), a Parasitoid of Bactericera cockerelli (Hemiptera: Trizoidae). Journal of Economic Entomology 105: 490-496.
  • Mogren, C.L., G. R. von Kiparski, D. Parker, and J. T.Trumble. 2012. Survival, reproduction, and arsenic body burdens in Chironomus riparius exposed to arsenate and phosphate. Science of the Total Environment 425: 60-65.
  • Hladun, K.R., B. H. Smith, J. Mustard, J. T. Trumble. 2012. Selenium toxicity to honey bee (Apis mellifera L.) pollinators: Effects on behaviors and survival. PLoS One. 7:334137; doi:10.1371/journal.pone.0034137.
  • Butler, C.D., and J. T. Trumble. 2012. Spatial dispersion and binomial sequential sampling for the potato psyllid (Hemiptera: Triozidae) on potato. Pest Management Science. 68: 865-869.
  • Butler, C.D., G.P. Walker and J.T. Trumble. 2012. Feeding disruption of potato psyllid, Bactericera cockerelli, by imidacloprid as measured by electrical penetration graphs. Entomologia Experimentalis et applicata 142:247-257.
  • Butler, C.D., and J. T. Trumble. 2012. Bactericera cockerelli (Sulc) (Hemiptera: Triozidae): life history, relationship to plant diseases, and management strategies. Terrestrial Arthropod Reviews 5: 87-111.


Progress 01/01/11 to 12/31/11

Outputs
OUTPUTS: We have completed a series of projects dealing with the invasive potato psyllid and the accumulation of the pollutant selenium in an weed species. The potato psyllid research has examined the potential for biological control and developed sampling programs for the psyllid that will help growers avoid unnecessary pesticide applications. In addition we have examined the behavioral effects of chemicals on psyllids that demonstrate why some pesticides can reduce transmission of a key pathogen at levels that do not kill the psyllid. Other experiments, we have documented the accumulation of selenium in an invasive weed species. PARTICIPANTS: K. Hladun and C. Butler are PhD students in the Trumble lab. D. Parker is a collaborator in the Environmental Sciences Department at UCR; J. Munyaneza, M. Keremane, R. Lee and R. Novy are collaborators at the USDA; T. Liu, C. Miller Jr., and L. Peng are collaborators at Texas A&M University; and F. Byrne is a collaborator in the Department of Entomology at UCR. TARGET AUDIENCES: Target audiences include scientists and growers. Many presentations were given to scientific groups during meetings in the USA, France, and New Zealand. Many other presentations were provided for growers in Claifornia, New Zealand, and Texas. PROJECT MODIFICATIONS: No major changes were made in the project.

Impacts
The objectives of one study were to determine the effects of potato germplasm on adult potato psyllid behavior and transmission of Ca. L. psyllaurous. A total of twenty-two potato (Solanum tuberosum L.) breeding clones and varieties were examined. Plant genotype significantly affected the occurrence and duration of psyllid probing, the duration of psyllid cleaning, resting and the amount of time psyllids spent off the potato leaflet as well as transmission of Ca. L. psyllaurous. I a second study we describe, for the first time, new records of hyperparasitism that could influence the use of biological controls against the psyllid. We also investigated the use of repellents, and found several that growers are now using. For the psyllid, one of our studies examined the impact of pesticides on psyllid behaviors that influence transmission of the pathogen. In our pollution studies, our main objective was to investigate the accumulation of Se in two Brassicaceae species chosen for their potential as phytoremediators of Se contaminated soils. Nectar and pollen in S. pinnata contained up to 150ppm wet weight and 12900 ppm dry weight when irrigated with 8 uM selenate. Se levels in nectar (110 ppmwet weight) and pollen (1700 ppm dry weight) were not as high in B. juncea. Floral display width, petal area and seed pod length were significantly reduced in the 13 uM selenate Se treatment in B. juncea. S. pinnata floral traits and seeds were unaffected by the Se treatments. This study provides crucial information about where some of the highest concentrations of Se are found in two phytoremediators, and may shed light on the potential risks pollinators may face when foraging upon these accumulating plants.

Publications

  • Butler, C.D., B. Gonzalez, K. Manjunath, R.F. Lee, R.G. Novy, C. Miller Jr., and J.T. Trumble. 2011. Behavioral responses of adult potato psyllid, Bactericera cockerelli (Hemiptera: Triozidae), to potato germplasm and transmission of Candidatus Liberibacter psyllaurous. Crop Protection 30: 1233-1238.
  • Butler, C.D. and J. T. Trumble. 2011. New records of hyperparasitism of Tamarixia triozae (Burks) by Encarsia spp. in California. Pan Pacific Entomologist. 87: 130-133.
  • Hladun, K. R., D. R. Parker and J. T. Trumble. 2011. Selenium accumulation in the floral tissues of two Brassicaceae species and its impact on floral traits and plant performance. Environmental and Expt. Botany 74: 90-97.
  • Peng, L. J. T. Trumble, J.E. Munyaneza, abd T.-X. Liu. 2011. Repellency of a kaolin particle film to tomato psyllid, Bactericera cockerelli (Homoptera: Psyllidae) on tomato under laboratory and field conditions. Pest Management Science 67: 815-824.
  • Butler, C. D., F. J. Byrne, M. L. Keremane, Richard F. Lee, and J. T. Trumble. 2011. Effects of Insecticides on Behavior of Adult Bactericera cockerelli (Hemiptera: Triozidae) and Transmission of Candidatus Liberibacter psyllaurous. J. Economic Entomology 104: 586-594.


Progress 01/01/10 to 12/31/10

Outputs
OUTPUTS: Research on the potato psyllid has allowed us to begin development of a comprehensive IPM program that uses the best available strategies in an areawide approach to management. . We have investigated new chemistries, biocontrol strategies, and putatively resistant plant varieties. The results of our work have been disseminated through publication, numerous meetings with scientists and growers in California, Texas, and New Zealand. Powerpoint reports have also been made available to growers at these locations. Research on pollutants, particularly selenium, has been presented to scientists at the Entomological Society of America, the Ecological Society of America, and many other outlets. PARTICIPANTS: The training opportunities have been substantial. Several post doctoral candidates, graduate students, and undergraduate students are employed and trained on this project. J. Munyaneza, J. M. Crosslin, R. Novy (all USDA in Washington State), C. Rush, D. Henne and C. Millar (from Texas A&M), and G. Walker, W. Walton and D. Parker (from UC Riverside) are actively cooperating on the project. Trumble's lab has J. Diaz as a post-doc, Casey Butler, K. Hladun and C. Mogren are graduate students, and J. Butler working as an undergraduate on the project. Partner organizations include the California Potato Board, the California Pepper Commission and the US Potato Commission. TARGET AUDIENCES: The target audiences for this research include scientists and growers.J. Trumble has made multiple presentations to scientists at Plant and Food Research of New Zealand. Grower extension presentations were made in California (the California Potato Board, the California Pepper Commission), and scientific presentations have been given at the Annual meeting of the Entomological Society of America), the Ecological Society of America, the Annual Zebra Chip Conference in Texas, and at many locations in New Zealand (including Mount Albert, Palmerston North, Havelock North and Pukekohe). PROJECT MODIFICATIONS: No major changes have been made in the direction or objectives of this project this year.

Impacts
For the psyllid research, the primary outcome has been a change in the understanding that many pesticides reduce transmission of the bacterial pathogen by the potato psyllid through repellency, not simply by killing the psyllid. This has led to a change in knowledge through an aggressive effort to disseminate the information to growers. Growers are beginning to change their pesticide use patterns from very intensive multiple applications using carbamates, organophosphates and pyrethroids, to a more sustainable approach using greener chemistries and application techniques. This more sustainable approach also allows us to manage the potential development of pesticide resistance. As a result we are beginning to see a change in conditions whereby fewer pesticide applications are made. This results in reduced costs to the grower and enhanced profitability, and as importantly, reduced farm worker and consumer exposure to agricultural chemicals. For the pollution research, we have highlighted the impacts of pollutants on insect behavior and documented the comparative importance of top-down (natural enemies) versus bottom-up (plant nutrition) factors on insect population regulation in polluted environments. Also, we have determined that climate change will likely result in major changes in distribution of a key parasitoid important in commecial agriculture.

Publications

  • Yang, X., Zhang, Y., Hua, L., Pang, Y., Munyaneza, J., Trumble, J.T., Liu, T. 2010. Repellency of a kaolin particle film to the potato psyllid, Bactericera cockerelli (Homoptera: Psyllidae). Crop Protection 29:1320-1324.
  • Mogren, C.L. and Trumble, J.T. 2010. The Impacts of Metals and Metalloids on Insect Behavior. Entomologia Experimentalis et Applicata 135: 1-17.
  • Butler, C. D., and J. T. Trumble. 2010. Predicting population dynamics of the parasitoid Cotesia marginiventris (Cresson) (Hymenoptera: Braconidae) resulting from novel interactions of temperature and selenium. Biocontrol Science and Technology 20: 391-406.


Progress 01/01/09 to 12/31/09

Outputs
OUTPUTS: Trumble, J.T. 2009. The Potato Psyllid: History, Population Genetics, and Management Department of Entomology, University of Florida, Lake Alfred, FL. Butler, C and J. T. Trumble. 2009. Sampling and IPM of psyllids. Citrus huanglongbing and zebra chip conference: Status of diseases and research opportunities. McAllen TX. Trumble, J. T. 2009. History, Range and Scope of the Potato Psyllid Problem. Citrus huanglongbing and zebra chip conference: Status of diseases and research opportunities. McAllen TX. Hladun, K. and J. T. Trumble. 2009. Selenium accumulation in the floral tissues of two Brassicaceae plant species: Implications for plant-pollinator interactions. Ecological Society of America Albuquerque, New Mexico. Hladun, K. and J. T. Trumble. Selenium accumulation in floral tissues of two phytoremediating Brassicaceae plant species: Implications for biotransfer to insect pollinators. 2nd Annual University of California Toxic Substances Research and Teaching Program Symposium. Berkeley CA. Trumble, J. T. 2009. The Geoffery Scudder Lecture: The challenges of Climate Change for Entomology, Agriculture, and the World's Food Supply. University of British Columbia, Canada British Columbia, Canada. Trumble, J. T. 2009. Challenges in a changing world: Climate change, entomology and agriculture. International Congress of Global Warming on Biodiversity of Insects: Management and Conservation. Coimbatore, India. Trumble, J.T. 2009. Interactions of selenium with other pollutants in aquatic and terrestrial food webs. Environmental Toxicology Seminar series. UC Riverside. Trumble, J. T. 2009. IPM practices in Celery. California Celery Research Board, Guadalupre CA. Trumble 2009. IPM in peppers. California Pepper Commission, Five Points, CA. PARTICIPANTS: Individuals: M. Sorensen, C. Butler, P. Jensen, and K. Hladun are graduate students. Liu, Jeske, Hu, Kang, Heinz, Beckage and Parker are collaborating faculty. Chase-Dunn, Morton, and Gilbert are undergraduate students. Gonzalez, Carson and Kund are technicians. Partner Organizations: Chinese Academy of Sciences, Texas A and M University, The California Celery Research Advisory Board, The California Pepper Commission, US Potato Commission, USDA, EPA. Training and profesional Development: all of the graduate and undergraduate students. TARGET AUDIENCES: Celery, potato, tomato and pepper growers. Growers and scientists in selenium-contaminated areas. PROJECT MODIFICATIONS: Nothing significant to report during this reporting period.

Impacts
Growers learned how to control psyllids, leafminers, Spodoptera species, etc. in several crops including potatoes, peppers, celery and tomatoes. Provided expanded information on resistant plant varieties, chemical control strategies with reduced toxicity materials, new biocontrol options for insect control, and improved sampling techniques. In addition, determined the effects of selenium on insect plant interactions dealing with pollinators. Finally, examined the effects of global warming on insects, integrated pest management practices and the global food supply.

Publications

  • Sorensen, M.A., Chase-Dunn, C.M., Trumble, J.T. 2009. Chronic exposure to elevated levels of manganese and nickel is tolerated by a cosmopolitan detritivore, Megaselia scalaris (Loew) (Diptera: Phoridae) . Insect Science. Vol. 16: p.73-79.
  • Sorensen, M.A., Parker, D., Trumble, J.T. 2009. Pollutant accumulation by the invasive weed saltcedar (Tamarix ramosissima) and transfer to the biological control agent Diorhabda elongata (Coleoptera: Chrysomelidae). Environmental Pollution. Vol. 157: p.384-391. Jeske, J., Xu, H.K., Jensen, P.D., Trumble, J.T. 2009. Testing for the equality of EC50 Values in the presence of unequal slopes with application to toxicity of selenium types. Journal of Agricultural, Biological and Environmental Statistics 14:. p.469-483.
  • Butler, C.D., Trumble, J.T. 2010. Predicting population dynamics of the parasitoid Cotesia marginiventris (Cresson) (Hymenoptera: Braconidae) resulting from novel interactions of temperature and selenium. Biocontrol Science and Technology. Vol. 20: p.391-406.
  • Trumble, J.T. 2009. Natural Products used in Pest Control. Encyclopedia of Entomology (Second Edition). Editors: J. Capinera. Springer. p.2570-2574.
  • Trumble, J.T., Butler, C.D. 2009. Climate change will exacerbate California's insect pest problems. California Agriculture. Vol. 63: p.73-78.
  • Butler, C.D., Beckage, N., Trumble, J.T. 2009. Effects of terrestrial pollutants on insect parasitoids . Environmental Toxicology and Chemistry. Vol. 28: p.1111-1119.
  • Liu, T., Kang, L., Heinz, K., Trumble, J.T. 2009. Biological control of Liriomyza leafminers: Progress and prospects. CAB Reviews: Perspectives in Agriculture, Veterinary Science, Nutrition and Natural Resources . Vol. 4: p.1-16.
  • Kund, G., Carson, W.G., Trumble, J. 2009. Effect of insecticides on pepper insects, 2008. Arthropod Management Tests. Vol 34: E44. Arthropod Management Tests.
  • Kund, G., Carson, W.G., Trumble, J. 2009. Effect of insecticides on celery insects, 2007. Arthropod Management Tests. Vol 34: E20. Arthropod Management Tests.
  • Carson, W.G., Kund, G., Trumble, J. 2009. Effect of insecticides on tomato insects, 2008. Arthropod Management Tests. Arthropod Management Tests. Vol 34:E68. Arthropod Management Tests.


Progress 01/01/08 to 12/31/08

Outputs
OUTPUTS: The research was disseminated to both the scientific community and the appropriate stakeholders by publication and by presentations. The key presentations are listed as follows: Trumble. J.T. 2008. Plant resistance, and management strategies for the potato psyllid. 2008 Annual Zebra Complex Meeting. Dallas TX. Hansen, A.K., J.T. Trumble, R. Stouthamer, and T.D. Paine. 2008. A New Huanglongbing species, "Candidatus Liberibacter psyllaurous,"found to infect tomato and potato, is vectored by the psyllid Bactericera cockerelli (Sulc). Zebra Complex Meeting. Dallas TX. Trumble. J.T. 2008. Predicting parasitoid population dynamics resulting from novel interactions of climate change and selenium pollution. 56th Annual Meeting of the ESA. Reno NV. Trumble. J.T. 2008. Insect adaptibility to warming environments: Implications for natural resources and human livelihoods. Program Symposium entitled: An entomological perspective addressing challenges in the developing world: New frontiers in food and bio-security. 56th Annual Meeting of the ESA. Reno NV. Trumble. J.T. 2008. Implications of global climate change for pest management. UC Pest Management Coordinating Conference. University of California. Davis, CA. Trumble. J.T. 2008. Implications of global climate change for pest management. UC Pest Management Coordinating Conference. University of California. Davis, CA. Trumble. J.T. 2008. Ecology of the potato psyllid, a new invasive insect in California. Psyllid Yellows Workshop. College of Natural and Agricultural Sciences and the Citrus Research Board. Riverside, CA. Trumble. J.T. 2008. Interactions of selenium with other pollutants on aquatic and terrestrial food webs. 93d Annual Meeting. Ecological Society of America. Milwaukee, WI. Hladun, K. and J.T. Trumble. 2008. Selenium accumulation in floral tissues of Brassica junaceae: implications for pollentaion ecology. Ecological Society of America. Milwaukee, WI. Butler, C. and J.T.Trumble. 2008. Effects of metal contamination on bottom up and top down processes in insect plant interactions. Ecological explorations of plant elemental defenses. Ecological Society of America. Milwaukee, WI. Butler, C. and J. T. Trumble. 2008. Predicting parasitoid population dynamics resulting from novel interactions of climate change and anthropogenic pollutation. Annual Meeting of the Pacific Branch Entomological Society of America. Napa Valley, CA. Trumble. J.T. and M.A. Sorensen 2008.. Proposed protocol for testing the elemental defense hypothesis. Annual Meeting of the Pacific Branch Entomological Society of America. Napa Valley, CA. Trumble. J.T. 2008. Integrated pest management strategies for insects infesting Capsicum crops. Ventura Vegetable Production Meeting. Camarillo, CA. PARTICIPANTS: M. Sorensen, A. Hansen, K. Hladun, and . Butler are graduate students that were provided training by the project. John Trumble, T. Paine, and R. Stouthamer are faculty at the University of California Riverside Department of Entomology. TARGET AUDIENCES: The target audiences include ecologists and other scientists studying the effects of pollution on the food web, legislators requiring information on the impacts of pollutants, and growers seeking to understand the effects of pollutants on biological control agents in their agroecosystems. PROJECT MODIFICATIONS: Not relevant to this project.

Impacts
In the manuscript by Trumble and Sorenesen, we suggest that three falsifiable null hypotheses can be constructed to test the theory of elemental defense for Se-containing plants. The first hypothesis is that the fitness of a plant without Se and without herbivores is equal to the fitness of a plant without Se and in the presence of herbivores. Disproving the first null hypothesis demonstrates that herbivores have fitness effects for this plant.. The second hypothesis states that the fitness of a plant with Se and in the presence of herbivores is equal to the fitness of a plant without Se and in the presence of herbivores. Disproving the second null hypothesis demonstrates that the presence of Se has fitness consequences for herbivores. The third hypothesis predicts that the fitness of a plant with Se but without herbivores is equal to the fitness of a plant without Se and without herbivores. Note that failing to disprove this last hypothesis does not disprove the elemental defense hypothesis, but merely suggests that alternative hypotheses explaining Se hyperaccumulation should also be considered. In the Hansen et al. publication, a new huanglongbing (HLB) "Candidatus Liberibacter" species is genetically characterized, and the bacterium is designated "Candidatus Liberibacter psyllaurous." This bacterium infects the psyllid Bactericera cockerelli and its solanaceous host plants potato and tomato, potentially resulting in "psyllid yellowing." Host plant-dependent HLB transmission and variation in psyllid infection frequencies are found. In the Butler and Trumble publication, we examine the impact of pollutants on the bottom-up (host plant quality) and top-down (natural enemies) forces that influence the fitness and population dynamics of herbivores. A comprehensive literature search found 126 references which examined fitness components and population dynamics of 203 insect herbivores. One-hundred fifty-three of the 203 herbivores (75.4%) had fitness impacted due to bottom-up factors in polluted environments. In contrast, only 20 of the 203 (9.9%) had fitness significantly impacted due to top-down factors in polluted environments. The paucity of results for top-down factors impacting fitness does not necessarily mean that top down factors are less important, but rather that fewer studies include natural enemies. We provide a synthesis of available data by pollution type and herbivore guild, and suggest future research to address this issue.

Publications

  • Trumble, J. T. and M. A. Sorensen. 2008. Selenium and the elemental defense hypothesis. New Phytologist 177: 569 to 572.
  • Hansen, A.H., J. T. Trumble, R. Stouthamer, and T.D. Paine. 2008. New Huanglongbing (HLB) Candidatus species, C. Liberibacter psyllaurous, found to infect tomato and potato is vectored by the psyllid Bactericerca cockerelli (Sulc). Applied and Environmental Microbiology 74: 5862 to 5865. 


  • Butler, C.D. and J. T. Trumble. 2008. Effects of pollutants on bottom-up and top-down processes in insect-plant interactions. Environmental Pollution 156: 1 to 10.


Progress 01/01/07 to 12/31/07

Outputs
OUTPUTS: Studies were completed inn two broad areas: control of invasive species and effects of pollutants on ecosystem function. In the first study, two genetically distinct potato psyllid populations [Bactericera cockerelli (Sulc) (Homoptera: Psyllidae)] were identified. An invasive population, ranging from Baja, Mexico to central California, was the result of a recent invasion, while the native population is endemic to Texas. The native (Texas) and invasive (California) populations were collected from tomato and pepper, respectively, and were examined on both hosts to test the comparative fitness of invasive populations. Our results indicated that on both plant hosts, psyllids from the native range demonstrated higher survivorship, a higher growth index, and shorter development times than the psyllids from invasive populations. These data were then used to evaluate a key hypothesis regarding invasive species. In a second study, Microplitis bicoloratus Chen (Hymenoptera:Braconidae:Microgastrinae), a new species of Microplitis from China and a solitary endoparasitoid of the larvae of the cotton leafworm, Spodoptera litura (Fabricius) (Lepidoptera: Noctuidae) was investigated. This parasitoid is the first to be successfully reared and evaluated in the laboratory as a potential agent for the biological control of S. litura in China. Oviposition, immature development, and the effects of parasitism on the development of S. litura were studied. In a third study, the effects of two widespread environmental pollutants, perchlorate and hexavalent chromium, were assessed on the efficacy of Bacillus thuringiensis subsp. israelensis (Bti) and Bacillus sphaericus (Bsph) against fourth instars of Culex quinquefasciatus Say (Diptera: Culicidae) in 24-h laboratory bioassays. In the presence of hexavalent chromium, improved suppression could be expected from Bacillus applications at the current label rates. However, because hexavalent chromium has been shown to affect many taxa, we propose that the potential exists for increased susceptibility of nontarget organisms to Bacillus products in polluted habitats. In the forth study, the southern house mosquito (Culex quinquefasciatus: Diptera), was used to test the individual and joint effects of dissolved sodium selenate (Se) and methyl mercury chloride (MeHg). We conducted ovipositional preference tests and 14-day chronic toxicity studies to determine lethal and sub lethal responses of C. quinquefasciatus to a range of Se and MeHg concentrations and mixtures. These are the first reported survival and developmental data for an aquatic insect exposed to MeHg and Se-MeHg mixtures. PARTICIPANTS: Participants fall into two categories. The following participants were students at the times the papers were written: Dr. Deguang Liu, Dr. Peter Jensen, and Dr. Mary Sorensen were PhD students in my laboratory, and Mr. Lou was a student in Dr. Pang's lab. This research provided extensive training experiences for all of these students. Dr. Walton is a Professor at UC Riverside and collaborated on the projects. Dr. Pang is a Professor at Sun Yat-Sen (Zhongshan) University, Guangzhou, China, and had the leading role on the paper by Lou. TARGET AUDIENCES: Studies on the invasive psyllid species were designed for both farmers and scientists. Farmers received information regarding movements and suppression of outbreak populations, while scientists were provided evidence that a key hypothesis regarding invasive species may not be reliable for invasive insect populations. The environmental toxicology research reported here was designed to provide scientists, government personnel (national, state and local), and the interested public with scientifically valid information regarding the effects of key pollutants on important ecosystems.

Impacts
The manuscripts on invasive species document important ecological and physiological differences between invasive and native populations of an aggressive new pest of potatoes, tomatoes and peppers. These data help to further define the current ecological hypotheses dealing with invasive species. In addition, the study on parasites is the first to provide evidence that a biological control agent could be suitable for controlling a major economic pest in China. The studies on environmental toxicology are the first to examine the independent and combined effects of selenium and mercury (both major pollutants in the USA) on insects. Similarly, the study describing the independent and combined effects of the wide spread pollutants perchlorate and hexavalent chromium on mosquito control strategies is the first study of this system. The results suggest that current control strategies may need to be modified in the vast region of the southern USA that is co-contaminated with these pollutants.

Publications

  • Liu, D. and J. T. Trumble. 2007. Comparative fitness of invasive and native populations of the potato psyllid (Bactericera cockerelli) Entomologica Experimentalis et applicata 123:35-42. 


  • Luo, K., J.T. Trumble, and Y. Pang. 2007. Life history of Microplitis bicoloratus on Spodoptera litura and implications for biological control. BioControl. 52:309-321.
  • Jensen, P. D. M. A. Sorensen, W. E. Walton, and J. T. Trumble. 2007. Lethal and sublethal responses of an aquatic insect Culex quinquefasciatus (Diptera: Culicidae) challenged with individual and joint exposure to dissolved sodium selenate and methyl mercury chloride. Environmental Toxicology 22:287-294. 


  • Sorensen, M. A., W. E. Walton, and J. T. Trumble. 2007. Impact of the inorganic pollutants perchlorate and hexavalent chromium on the efficacy of Bacillus sphaericus and Bacillus thuringiensis subsp. israelensis against Culex quinquefasciatus. J. Medical Entomology 44: 811-816


Progress 01/01/06 to 12/31/06

Outputs
Despite the important roles played by insects in most ecosystems, surprisingly little is known about how anthropogenic pollutants or their mixtures interact to affect insect populations. The independent and joint actions of selenate and methylmercury on a ubiquitous insect detritivore, Megaselia scalaris (Loew), were determined our first study. Ovipositing females did not distinguish between untreated food sources and those contaminated with toxic concentrations of selenate, methylmercury, or both chemicals in combination. Even at the highest concentrations of pollutants, no negative effects were observed for the egg stage. However, larval survival was significantly decreased and development significantly prolonged by selenate and methylmercury individually at low or intermediate ecologically relevant treatment levels. Potentiation was strongly evident because mixtures containing concentrations as little as only 1% of the respective individual median lethal tolerances (LC50s) caused significantly more mortality and delayed larval development than would be expected from the responses selenate and methylmercury elicit individually. However, survival and pupal development was not affected at any rate tested. Female fecundity was significantly decreased by methylmercury but not by selenate or mixture treatments. The relative toxicity to M. scalaris of each of the individual and joint treatments was selenate (LC50 = 260 lg/g) < methylmercury (LC50 = 22 lg/g) < the mixture at approximately 5% of the LC50 concentration of each of the components (12 lg/g selenate plus 1.0 lg/g methylmercury). The increased mortality and delayed larval development within sites contaminated by selenate, methylmercury, or combination of the two have substantial implications for the ecology, population dynamics, and sustainability of M. scalaris populations. If these results can be extrapolated to other arthropod detritivores, ecosystem food-web function may be substantially affected. In a second study, the effects of water contamination with perchlorate and hexavalent chromium [Cr (VI)] were assessed on the mosquito, Culex quinquefasciatus. The chronic (10-day) LC50s values for perchlorate and chromium were 74+/-8.0 mg/L and 0.41+/-0.15 mg/L, respectively. Relative Growth Index, a measure of growth and mortality rates in a population, was significantly reduced within 5 days for levels of perchlorate as low as 25 mg/L and for levels of chromium as low as 0.16 mg/L. Neither compound altered wing length of surviving adults. In combination, contaminants were synergistic, causing 14% more mortality than predicted. Acute (24-h) LC50 values for perchlorate and Cr (VI) were 17,000+/-3200 and 38+/-1.3 mg/L, respectively. Effects on mosquito larvae in contaminated environments are likely to be observed for Cr (VI) but not for perchlorate, which generally does not occur at levels as high as those shown here to affect larval mosquitoes.

Impacts
To our knowledge, this is the first study to examine the joint effects of selenate and methylmercury on any species of arthropod. Interestingly, the relationship between selenate and methylmercury was not antagonistic as would be predicted from previous studies on fish, birds, and mammals. Not only was the relationship not antagonistic, the two compounds had a significant potentiation effect, causing much greater toxicity than we would have expected from their individual toxicities. We speculate that the reason for the potentiation rather than antagonism may be because of the lack of Se dependent glutathione peroxidase in some insects, which acts as an important component of the antioxidant system in mammals. This work suggests that man-made pollutants will have a much greater effect on organisms at the bottom of the food chain that has been previously estimated. The second study also showed significant potentiation when two pollutants were combined. Thus, this pattern suggests that single pollutant tests may underestimate the impacts of pollutants when multiple compounds are present.

Publications

  • Sorensen, M. A., Jensen, P. D., Walton, W. E., and Trumble, J. T. 2006. Acute and chronic activity of perchlorate and hexavalent chromium contamination on the survival and development of Culex quinquefasciatus Say (Diptera: Culicidae). Environmental Pollution 144: 759-764.
  • Jensen, P. D., Johnson, L., and Trumble, J.T. 2006. Individual and joint action of selenate and methylmercury on the development and survival of an insect detritivore Megaselia scalaris (Diptera: Phoridae). Archives of Environ. Contamination 50: 523-530.