|ALARC Highlights Winter/Spring 2013|
Featured Recent Accomplishment
Uptake and Accumulation of Pharmaceuticals by Nasturtium Irrigated with Water Containing 20 Different Human Drugs. The use of reclaimed municipal sewage for irrigation can be seen as a potential new source of water in arid and semi-arid regions of the world. However, reclaimed water contains very low concentrations of pharmaceuticals including prescription and over-the-counter drugs. One potential obstacle to reusing reclaimed water for irrigation of food crops is the uptake of these drugs and the introduction of these compounds into the human food chain. The source of pharmaceuticals in reclaimed water includes everything from disposing of unused prescription drugs down the drain to excretion of unmetabolized drugs by individuals using the drugs for therapeutic purposes. In addition, most wastewater treatment plants are not designed to remove pharmaceuticals from raw sewage.
To investigate the potential for drug uptake and accumulation, nasturtiums (Figure 1) were irrigated with solutions containing 20 different drugs (Table 1) at very high concentrations for 90 days and harvested to determine the mass of drug accumulated.
In general it was found that the highest drug concentrations were found in the roots and leaves. The high concentrations in the roots can be attributed to being in contact with the drug in the soil solution. High concentration of the drugs in the leaves would also be expected due to evaporation of water taken up by the plant. The drugs are carried through the plant in translocated water and then would be left behind and accumulated in the leaves as this water evaporates through the leaf surface. The accumulation in the leaves has implications for irrigating leafy vegetables, like lettuce, for human consumption.
Table 1. Pharmaceutical compounds used in the plant uptake experiment and the mass of compound accumulated in the whole plant.
Total drug uptake was greatest for the topical anesthetic lidocaine with 78.5% of the applied drug accumulating in the plant; no uptake was found for the antibiotics oxytetracycline and triclosan. Nine of the compounds accumulated less than 1% of the applied compound and only three of the compounds had accumulations greater than 10%. Lidocaine, carbamazepine and diphenhydramine accumulation indicated that there is a potential hazard from these three drugs; however, the actual mass of these compounds in the entire plant is 10 to 50 times lower than a typical single recommended dose. Currently, ongoing experiments are in progress to measure the uptake of drugs from water at the much lower concentrations typically found in wastewater sources.
Contact: Clinton Williams (Clinton.firstname.lastname@example.org)
Other Recent Accomplishments
Bt resistance genes in pink bollworm.Transgenic Bt cotton, cotton that makes insecticidal proteins from the bacterium Bacillus thuringiensis (Bt) is an essential tool of the Pink Bollworm Eradication Program. Genes conferring resistance to Bt cotton are known to occur in the pink bollworm, and although control failures have not been observed in the U.S., field populations of Bt-resistant pink bollworm have appeared in other countries. In collaboration with colleagues from the University of Arizona, an ARS scientist in Maricopa, AZ showed that resistance to Bt cotton is genetically linked with changes in the pink bollworm cadherin gene, and that one such cadherin mutation involved an insertion of a mobile DNA element or "jumping gene." The ARS scientist also identified a new gene from the pink bollworm, bringing the total to four known cadherin mutations genetically linked to Bt resistance. Results implicate changes to the cadherin gene as the predominant mechanism of pink bollworm resistance to Bt cotton, and accentuate the importance of cadherin-based resistance monitoring to preservation of this critically important control technology. (Contact: Jeff.Fabrick@ars.usda.gov)
Transgenic crop has no effect on important insect predator. Transgenic crops producing the target-specific insecticidal proteins of Bacillus thuringiensis (Bt) have been widely adopted and cultivated on millions of hectares globally. However, there remain concerns about the ecological risk associated with these crops, specifically to non-target organisms. An ARS scientist in Maricopa, AZ, and researchers at Cornell University, ARS in Ames, IA, and Agroscope in Zurich, Switzerland showed that the biology of a common predatory lady beetle was not affected by ingestion of Bt-resistant prey fed on Bt-maize over two generations. Use of Bt-resistant prey instead of susceptible prey overcame a common problem with such assays by ensuring any observed effects were caused by the Bt toxin instead of by poor prey quality. Results are valuable to governmental authorities responsible for regulating transgenic crops, other scientists, and a general public concerned about the environmental effects of biotechnology. (Contact:Steve.Naranjo@ars.usda.gov)
A molecular approach to studying arthropod predation. Understanding predator-prey interactions of the arthropod predator community is essential for pinpointing ecosystem services provided by natural enemies. An ARS scientist in Maricopa, AZ, developed, optimized, and utilized a suite of prey-specific DNA-based assays to analyze the gut contents of the cotton predator community. The targeted insects included an herbivore pest (sweetpotato whitefly), a strict predator (collops beetle), an omnivorous pest (lygus bug), and an omnivorous predator (big-eyed bug). Gut analyses showed that the strict predator and both omnivores fed substantially on whiteflies. However, the two omnivores also fed on each other. Whitefly and lygus were more frequently eaten by insect predators than by spiders, whereas the two beneficial species (big-eyed bug and collops beetle) were fed upon by both insect and spider predators. This study serves as a model to demonstrate the utility of DNA-based methods in elucidating complex food web interactions. (Contact:James.Hagler@ars.usda.gov)
Elevated atmospheric CO2 and drought effects on leaf gas exchange properties of barley. Atmospheric CO2 concentration is rising, predicted to cause global warming and alter precipitation patterns. Uncertainty exists about how barley production will be affected by elevated atmospheric CO2 under ample and reduced water supply. ARS researchers from Maricopa, AZ and Potsdam-Institute for Climate Impact Research, Germany fumigated open-field barley plots with CO2 to 180 ppm above ambient levels of 370 ppm. This facilitated drought avoidance by reducing water loss through leaves, which conserved water and enabled leaves to transpire for a longer period into a drought, resulting in a 28% reduction in drought-induced, midafternoon depression in photosynthesis rate. The season-long average dry weight increased by 14%, under elevated CO2, whereas deficit irrigation reduced it by 7%. Overall, effects of elevated-CO2 on gas exchange properties enhanced growth of barley. (Contact:Gary.Wall@ars.usda.gov)
Factors inhibiting photosynthesis under heat and drought stress. Heat and drought stress reduce crop yield by inhibiting photosynthesis. In collaboration with the University of Arizona, ARS scientists in Maricopa, AZ, used high-throughput phenotyping methods to determine which photosynthesis related mechanisms in pima cotton are most sensitive to a combination of heat and drought stress in the field. Varieties differed in their response to drought with the more drought sensitive varieties exhibiting greater susceptibility to heat stress. The biochemical basis for this increased susceptibility to heat stress was identified as a metabolic limitation caused by inactivation of the carbon dioxide fixing enzyme Rubisco. The insights gained from the high-throughput methods developed in this study can be used to guide breeding and selection for more heat and drought tolerant cotton. (Contact:Mike.Salvucci@ars.usda.gov)
Identification of genes controlling cuticle formation. The plant cuticle is under genetic control, and is a major determinant of crop drought stress tolerance. ARS scientists in Maricopa, AZ, identified sequences of two new genes controlling cuticle metabolism, and whose products also regulate whole plant transpiration rates, and plant water conservation. Information generated in these studies sheds light on the cellular function of genes involved in cuticle synthesis, as well and the role of physico-chemical properties of the cuticle as a barrier to water loss. These genes have excellent potential to be used in crop improvement to breed for more drought tolerant crops, and work is now underway to test this potential in the important oilseed Camelina. (Contact:Matt.Jenks@ars.usda.gov)
WinSRFR 4.1 released to the public and Natural Resources Conservation Service (NRCS). The performance of gravity (surface) irrigation, the prevalent method of on-farm water application in the U.S. and worldwide, typically is low but can be substantially improved if systems are designed and/or operated based on hydraulic engineering principles. Researchers at ARS in Maricopa, AZ released Version 4.1 of WinSRFR, a surface-irrigation software program that can be used to analyze field evaluation data, estimate field infiltration properties, analyze design alternatives, optimize operations, and conduct simulation studies. The new software features an updated simulation engine (SRFR) that was reprogrammed using a design layout, which includes a modern graphical diagnostic and debugging tool. New functionalities include simulation with the Green-Ampt infiltration equation and surge irrigation modeling. Intended users include university extension agents, farm advisors, irrigation consultants, and NRCS irrigation specialists. (Contact:Eduardo.Bautista@ars.usda.gov)
Microbial content and activity in vegetative filter strips receiving antibiotics from soil applied animal manure. Vegetative filter strips are land areas of indigenous or planted vegetation providing a buffer between agricultural land and surface water bodies. The use of these strips has been proposed to prevent the runoff of antibiotics to surface water from manure-amended fields. However, antibiotics in runoff water entering the filter strips may adversely affect soil microbial populations and interfere with the filter strips ability to provide long-term treatment. Scientists in Maricopa, AZ measured the development of antibiotic resistance in soil microbial populations from existing vegetative filter strips. The presence of veterinary antibiotics did not affect soil microbial communities and use of vegetative filter strips may not be adversely affected by application of manures containing antibiotics to agricultural fields. These results provide further evidence that vegetative filter strips can provide sustainable improvements in surface water quality. (Contact:Clinton.Williams@ars.usda.gov)
Recent Journal PublicationsAsiimwe, P., Naranjo, S.E., Ellsworth, P.C. 2013. Relative influence of plant quality and natural enemies on the seasonal dynamics of Bemisia tabaci in cotton. Journal of Economic Entomology 106: 1260-1273. (PDF)
Brent, C.S., Klok, C., Naranjo, S.E. 2013. Effect of diapause status and gender on activity, metabolism and starvation resistance in the plant bug Lygus hesperus Knight. Entomologia Experimentalis et Applicata (in press) (PDF)
Byers, J.A. 2012. Modelling female mating success during mass trapping and natural competitive attraction of searching males or females. Entomologia Experimentalis et Applicata 145: 228-237. (PDF)
Chapman, K., Dyer, J., Mullen, R. 2013. Why don't plant leaves get fat? Plant Science 207: 128-134. (PDF)
Hagler, J.R., Blackmer, F. 2013. Identifying inter-and intraguild predator feeding activity of an arthropod predator assemblage. Ecological Entomology 38: 258Ð271. (PDF)
Hagler, J.R., Blackmer, F., Krugner, R., Groves, R.L., Morse, J.G., Johnson, M.W. 2013. Gut content examination of the citrus predator assemblage for the presence of Homalodisca vitripennis remains. Biocontrol 58:341-349. (PDF)
Henderson, J.N., Hazra, S., Dunkle, A.M., Salvucci, M.E., Wachter R.M. Biophysical characterization of higher plant Rubisco activase. 2013. Biochemica et Biophysica Acta: Proteins and Proteomics 1834: 87-97. (PDF)
Hull, J.J., Geib, S.M., Walk, T., Fabrick, J.A., Brent, C.S. 2013. Sequencing and de novo assembly of the western tarnished plant bug (Lygus hesperus) transcriptome. PLoS One. 8 (1): e55105. (PDF)
Kelly, J.L., Hagler, J.R., Kaplan, I. 2012. Employing immunomarkers to track dispersal and trophic relationships of piercing-sucking predator, Podisus maculiventris (Hemiptera: Pentatomidae). Environmental Entomology 41: 1527-1533. (PDF)
Kimball, B.A. 2013. Comment on 'Improving ecophysiological simulation models to predict the impact of elevated CO2 concentration on crop productivity' by X. Yin. Annals of Botany doi:10.1093/aob/mct130. (PDF)
Park, S., Gidda, S.K., James, C.N., Horn, P.J., Knuu, N., Seay, D.C., Keereetaweep, J., Chapman, K.D., Mullen, R.T., Dyer, J.M. 2013. THe alpha/beta hydrolase CGI-58 and peroxisomal transport protein PXA1 coregulate lipid homeostasis and signaling in Arabidopsis. Plant Cell 25: 1726-1739. (PDF) (Recommended by the Faculty of 1000)
Rajangam, A.S., Gidda, S.K., Craddock, C., Mullen, R.T., Dyer, J.M., Eastmond, P.J. 2013. Molecular characterization of the fatty alcohol oxidation pathway for wax-ester mobilization in germinated jojoba seeds. Plant Physiology 161:72-80. (PDF)
Sivakoff, F.S., Rosenheim, J.A., Hagler, J.R. 2012. Relative dispersal ability of a key agricultural pest and its predators in an annual agroecosystem. Biological Control 63: 296-303. (PDF)
Spurgeon, D.W., Cooper, W.R. 2012. Disinfestation of Beauveria bassiana from adult Lygus hesperus using ultraviolet-C radiation. Southwestern Entomologist 37: 449-457. (PDF)
Spurgeon, D.W., Cooper, W.R. 2013. Sweepnet captures of Lygus hesperus (Hemiptera:Miridae) adult genders and age-classes in cotton. Journal of Entomological Science (in press) (summary)
Swezey, S., Nieto, D., Hagler, J.R., Pickett, C., Bryer, J., Machtley, S. 2013. Dispersion, distribution and movement of Lygus spp. (Hemiptera:Miridae) in trap-cropped organic strawberries. Environmental Entomology (in press) (summary)
Thorp, K.R., French, A.N., Rango, A. 2013. Effect of image spatial and spectral characteristics on mapping semi-arid rangeland vegetation using multiple endmember spectral mixture analysis (MESMA). Remote Sensing of Environment. 132:120-130. (PDF)
Tian, J.C., Wang, X.P., Long, L.P., Romeis, J., Naranjo, S.E., Hellmich, R.L., Wang, P., Earle, E.D., Shelton, A.M. 2013. Bt crops expressing Cry1Ac, Cry2Ab and Cry1F do not harm the green lacewing, Chrysoperla rufilabris. PLoS One 8(3): e60125. (PDF)
Tian, J.C., Collins, H.L., Romeis, J., Naranjo, S.E., Hellmich, R.L., Shelton, A.M. 2012. Using field-evolved resistance to Cry1F maize in a lepidopteran pest to demonstrate no adverse effects of Cry1F on one if its major predators. Transgenic Research21:1303-1310. (PDF)
White, J.W., Hunt, L.A., Boote, K.J., Jone, J.W., Koo, J., Soonho, K., Porter, C., Wilkins, P.W., Hoogenboom, G. 2013. Integrated description of agricultural field experiments and production: the ICASA version 2.0 data standards. Computers and Electronics in Agriculture 96:1-12. (PDF)
Current Grant Awards (*new)
*Sustainable Management Practices for Bagrada Bug, USDA Specialty Crop Block Grant Program (through University of Arizona) (PI Steve Castle) 2013-2015.
*Assessment of Pheromone Interactions Between the Sexes of the Whitefly Bemisia tabaci, Binational Agricultural Research and Development Fund (BARD) (PI John Byers) 2013-2014
*Evaluation of the Cropgro-Cotton Model for Arizona Cotton Production Systems, Cotton Incorporated (PI Kelly Thorp) 2013-2014.
*Use of Agrotain in Improving Nitrogen Fertilizer Management in Surface-Irrigated Cotton, Koch Agronomic Services, LLC (PI Kevin Bronson) 2013.
*Applying Proximal Sensing to Enhance Upland Cotton Yield Trials, Cotton Incorporated (PI Andy French) 2013.
*Role of Omega-3 Fatty Acid Desaturase Genes in Cold Temperature Tolerance of Cotton, Cotton Incorporated (PI John Dyer) 2012-2013.
*Evaluating and Predicting H2O Consumption by Irrigated Agriculture in Israel and US: Inverse Biophysical Modeling Utilizing Spaceborne Imagery, Binational Agricultural Research and Development Fund (BARD) (PI Andy French) 2012-2015.
Accelerated Development of Commercial Hydrotreated Renewable Jet (HRJ) Fuel from Redesigned Oil Seed Feedstock Supply Chains, USDA-NIFA/DOE Biomass Research and Development Initiative (PI T. Isbell, Co-PIs Matt Jenks, Mike Gore, D. Long, D. Archer, S. Frey, D. Galloway, T. Tomlinson) 2012-2016.
Securing the Future of Natural Rubber: An American Tire and Bio-energy Platform from Guayule, USDA-NIFA/DOE Biomass Research and Development Initiative (PI H. Colvin, Co-PIs Mike Gore, C. McMahan, Matt Jenks, A. Halog, J. Mitchell, P. Zorner, Collaborator, Doug Hunsaker) 2012-2016.
Managing PierceÕs Disease in Arizona Vineyards, USDA Specialty Crop Block Grant Program through Arizona Department of Agriculture (PI Steve Castle) 2012-2014.
Identifying genetic markers associated with drought adaptive cuticle lipids in the bioenergy crop oilseed rape (Brassica napus), USDA-ARS Postdoctoral Associate Program (PI Matt Jenks) 2012-2014.
High-Throughput Phenotyping Using Portable LIDAR, Cotton Incorporated (PI Andy French with Co-PIs M. Gore, Cornell University and P. Andrade-Sanchez, University of Arizona) 2012-2013.
Impact of Bioenergy Crops on Pests, Natural Enemies and Pollinators in Agricultural and Non-Crop Landscapes, USDA-NIFA-AFRI (Co-PI James Hagler with T. Kring and R. Weidenman, University of Arkansas; B. McCornack, Kansas State University; K. Giles, Oklahoma State University) 2011-2016
Optimizing Applications of Plant-Systemic Insecticides against Vine Mealybug, USDA Specialty Crop Block Grant Program (through Univ. California, Riverside) (PI Steve Castle) 2011-2014.
Investigation into Effects of Soil Moisture Depletion on Vegetable Crop Uptake of Microcontaminants under Recycled Water Irrigation, USDA-NIFA-AFRI (PI Clinton Williams with C. Ray, University of Hawaii) 2011-2013
Optimizing Rubisco Regulation for Increased Photosynthetic Performance under Climate Change, DOE (PI Mike Salvucci) 2010-2013
Improving Nitrogen Fertilizer Management and Fate of Nitrogen in Surface Irrigated Cotton, Cotton Incorporated (PI Kevin Bronson) 2011-2013
Ecological and Agricultural Productivity Forecasting Using Root-Zone Soil Moisture Products Derived from the NASA SMAP Mission, NASA (Co-PI Kelly Thorp with W. Crow, USDA-ARS Beltsville [PI]; S. Moran, USDA-ARS Tucson; G. Nearing, University of Arizona; R. Reichle NASA) 2010-2014
Recent Professional Awards
Andrew Frenchreceived the 2013 Best Reviewer Award for the Journal of Irrigation and Drainage Engineering, awarded by Environmental and Water Resources Institute of the American Society of Civil Engineers
John Dyer recently published a paper in Plant Cell that was recommended by the Faculty of 1000. This unique honor is bestowed only on the top papers in all of biology. (PDF)
Current Editorial Appointments
Eduardo Bautistaserves as Associate Editor for Journal of Irrigation and Drainage Engineering published by the American Society of Civil Engineers
Colin Brent serves Subject Editor for Environmental Entomology published by the Entomological Society of America
Andrew French serves as an Associate Editor for Transactions of Geoscience & Remote Sensing published by the Institute of Electrical and Electronics Engineers, Inc.
James Hagler serves as Editor of the Journal of Insect Science, an independent journal published out of the University of Wisconsin
Steven Naranjo serves as Subject Editor for Environmental Entomology published by the Entomological Society of America; he also serves as Reviewing Editor of Frontiers of Plant Biotechnology published by Frontiers
Kelly Thorp serves as an Associate Editor for Transactions of the ASABE and Applied Engineering in Agriculture, both published by the American Society of Agricultural and Biological Engineers.
Jeff White serves as an Associate Editor for Crop Science, published by the Crop Science Society of America
Recent Events and Outreach
In November 2012 a delegation of Chinese water management specialists, led by Ms. Hu Yaqiong, Senior Research Engineer from the China Institute of Water Resources and Hydropower Research Center, visited ALARC. The delegation met with members of the Water Management and Conservation Research Unit to discuss ongoing research activities and identify potential opportunities for scientific cooperation under Annex X of the USDA-MOST Protocol. The group visited the Central Arizona Irrigation and Drainage District located in Eloy, AZ. This visit provided the provincial water managers with an opportunity to learn about water delivery rules and policy issues in the Western US, in particular about water pricing policies, how different water supplies are used by the District, water allocation mechanisms, and fee collection mechanisms. The group visited the University of Arizona, Maricopa Agricultural Center (MAC) in the afternoon, where they learned about extension programs in precision agriculture and water quality.
In January 2013, Dr. Amy Landis from at Arizona State University visited ALARC with six of her graduate students. They are collaborating with member of the Water and Plant units at the Center, Cooper Tire & Rubber Company and the Yulex Corporation USDA/DOE Biomass Research and Development Initiative (BRDI) project. This project is studying and conducting research in the use of guayule for biofuel feedstock. Field tours were made of the new Water Management and Conservation Unit irrigation studies on guayule, including a sub-surface drip irrigated guayule field.
In January 2013, four USDA-NRCS specialists from Tucson, Phoenix and Douglas, AZ, and Portland, OR, visited the Water Management and Conservation Unit of ALARC to discuss Arizona nutrient management standards and the WinSRFR program. WinSRFR, developed by Water Unit scientists, is used by AZ-NRCS to evaluate proposals under the Environmental Quality Incentives Program (EQIP) for improving surface irrigation systems.
In February 2013, the EEO committee kicked off Black History month by presenting Dr. Martin Luther King's "I have a Dream" speech, and "The Bicycle Corps: America's Black Army on Wheels." The video told the story of the 25th Infantry's bicycle trip from Missoula, Montana to St. Louis, Missouri in 1897. The African American infantry took the trip to test a theory that the bicycle would replace the horse in transporting men for the Army.
In February 2013, students from the James Madison Preparatory School Biology sophomore class located in Tempe, Arizona toured the ALARC. The students have been studying Mendelian Genetics, agriculture, and ecological adaptations of various species to the environment. These tours gave the students an opportunity to experience a "day-in-the life" of research scientists, ranging from plant physiology, entomology, microbiology, water management and wastewater treatment.
Also in February, Western Ag in the Classroom (WAITC), a group of educators representing 10 western states as part of the Agriculture in the Classroom (AITC) toured ALARC. AITC was established in 1981 and is an educational program designed to supplement and enhance a teacher's curriculum. The strength of AITC comes from its grass roots organization and the educators that are part of the program. The group will be attending a conference in Loveland, CO, June 19, 2013 at the "Rendezvous in the Rockies" conference. The focus of rendezvous is to provide Ag-literacy, educate, and share their experiences and awareness with, educators, administrators, curriculum developers, career guidance counselors, agricultural science teachers, extension educators, university staff, and agricultural industry representatives by sharing methods for incorporating real-life agricultural applications into classroom style language.
May 2013 was the annual ALARC's Bring your Kids to Work day. This was a great opportunity for our kids to see, touch, and feel the science that their parents are conducting. The day was filled with wonderful activities that included a Farm Field Tour, Isolating their own DNA, Robotics-Lab Automation, a Greenhouse tour, Computer/Intranet programming, Insects under the Microscope, Thermal Imaging, and Polymers to Slime. It was a wonderful day for the kids, as well as the parents.
In June, 2013 ALARC hosted the Summer Ag Institute (SAI). The SAI is a group of K-12 teachers, who embark on a week-long tour throughout Arizona. This adventure is designed to teach them about food and fiber production, and help them incorporate that knowledge in the classroom curriculum. This experience is a great opportunity for the teachers to see the vital role agriculture plays in rural communities and the importance of the research being conducted at our center. The group had the opportunity to tour various labs in the three research units, as well as seeing the "Avenger", a high clearance tractor that is being adapted to carry four sets of sensors to measure crop canopy height, temperature and reflectance.
Also in June, a group of young boys visited our center, as well as nearby guayule fields. This tour was coordinated with a Mother's Awareness on School-Age kids (MASK) representative. The mission of MASK is to educate both the parents and children on the issues facing our youth and to empower children to make safe, and healthy choices. The boys interacted with our three research units, as well as a hands-on demonstration of Thermal Imaging.
Once again, ALARC is hosting a number of high school interns this summer as part the Undergraduate Bioscience Engagement Track (uBET) program administered by South Mountain Community College (an HSI). This program is funded by a grant from the USDA-NIFA and aims to increase STEM training in local high schools, particularly for minority students. Students work with mentor scientists for 8 weeks while gaining college credit and developing a poster on their research project.