Dr. John D. Lea-CoxProfessor; Nursery Research and Extension SpecialistEmail: jlc@umd.edu |
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Education and Experience:
- University of Maryland, College Park (1996 - present).
- National Research Council Research Associate, Kennedy Space Center, FL (1993-1996).
- Ph.D. Plant Physiology from the University of Florida (1993).
- M.S. Horticulture from the University of Natal, South Africa (1989).
- Nursery Manager, Amanzi Estates, Uitenhage, South Africa (1983-1986).
- B.S. (Hons) in Horticulture from the University of Natal, South Africa (1983).
Area of Specialization:
I am the Research and Extension specialist for the Nursery industry in Maryland. My expertise is primarily in the areas of water and nutrient management to reduce the environmental impacts of our production practices. However, my interests are very broad and currently include general plant physiology, plant water relations, plant pathology, soilless substrates, water and nutrient modeling, production system dynamics, green roof systems and wireless sensor networks.
I am leading a five-year USDA Specialty Research Crops Initiative Sensor Networks grant (2009-2014). This $5.16M national coordinated agricultural project, combined with an additional $5.21M in matching funding from industry members, state institutions and other grant sources, brings together a multidisciplinary group of engineers, plant scientists, economists and extension specialists from five universities and two commercial companies to develop the next generation of precision water management tools, marrying plant science with economics, engineering and technology. These tools will allow growers to precisely monitor plant water use to allow better control of irrigation water and nutrient applications, and increase the profitability and efficiency of commercial plant producers. More information on this projct can be found at http://www.smart-farms.net
We have also partnered with Dr. Chuan Hong at Virginia Tech on research into Integrated Management of Zoosporic Pathogens and Pond Irrigation Water Quality. To date, this project has identified four known species that were not previously documented in irrigation water, and named two new species (P. irrigata and P. hydropathica). We have also assessed the pathogenicity of some existing and new taxa of Phytophthora species recovered from irrigation water. We have clearly demonstrated that bait choices, deployment method and exposure time affect the recovery of Phytophthora species from containment basins and subsequently formulated a protocol that provides the most effective and consistent detection of these pathogens in aquatic environments. This research has led to another five-year $2.7M SCRI Pathogen Management Grant (2010-2014) that seeks to learn how water quality parameters impact pathogen survival, design structural changes in irrigation pond systems and document the economic impact of waterborne pathogens and control methods.
We have also established a Sustainable Green Roof Systems Program that is focused primarily on developing low-impact sustainable substrates and providing tools to monitor the performance of green roofs for urban stormwater mitigation. This project also forms part of the SCRI sensor network grant. Lastly, but perhaps most importantly, I have a keen interest in developing effective web-based Knowledge Centers and e-learning courses, so that we can engage our undergraduate students in ongoing research, more effectively reach out to non-traditional audiences and develop better international partnerships.
University Courses:
- PLSC 430: Water and Nutrient Management Planning (Elective: 3 Credits)
- PLSC 432: Greenhouse Crop Production (Elective: 3 Credits)
- PLSC 460: Capstone - co-instructor with Dr. Scott Glenn (Coordinator)
- PLSC 461-4: Cultural Management for Nursery and Greenhouse Operations (4 credits)
I am the coordinator for this elective modular course - Cultural Management of Nursery and Greenhouse Operations; (1 credit per module x 4 = 4 Credits). This class is co-taught by Dr. Andrew Ristvey (PLSC 461 - Substrates) and Dr. David Ross (PLSC 462 - Irrigation Management and PLSC 463 - Surface Water Management) and myself (PLSC 464 - Nutrient Management)
Current Research Projects:
- Wireless Sensor Networks for Precision Water and Nutrient Applications [see www.smart-farms.net for more details]
- Integrated Management of Zoosporic Pathogens and Irrigation Water Quality [see www.irrigation-pathogens.info for more details]
- Modeling Stormwater Runoff and Efficiency of Extensive Green Roof Systems
Continuing and Recently Completed Extension Education Projects:
- Water and Nutrient Management Programs Nursery and Greenhouse Producers in Maryland
- A Knowledge Center for Water, Nutrient and Crop Health Management [see www.waternut.org for more details and access to the Knowledge Center Modules]
- Providing Online Access to the Journal of Environmental Horticulture
Current PostDoctoral Research Associates:
- Dr. Jongyun Kim - Modeling the Water Use of Antirrhinum cultivars
- Dr. John Majsztrik - Characterizing the Adoption and Economic Benefits of Sensor Technology Use in the Nursery and Greenhouse Industry
Current Graduate Students
- Olyssa Starry (PhD Candidate) - Modeling Stormwater Runoff and Efficiency of Extensive Green Roof Systems
Former Graduate Students
- John Majsztrik (PhD, 2011) - Modeling Nitrogen, Phosphorus and Water Dynamics in Greenhouse and Nursery Production Systems
- Lorelly Solano (MS, 2010) - Investigating Crumb Rubber Amendments for Extensive Green Roof Substrates
- Félix Arguedas-Rodriguez (MS, 2009) - Calibrating Capacitance Sensors to Estimate Water Content, Matric Potential and Electrical Conductivity in Soilless Substrates
- Matthew Stevens (MS, 2005) - Sustainability of Cold-Climate Strawberry Production Systems
- Andrew Ristvey (PhD, 2004) - Water and Nutrient Dynamics in Container-Nursery Production Systems
- Huijun Shang (MS, 2003) - An Investigation of Early Morning Temperature Change (DIF) and Red/Far-Red Ratio on the Morphological Development of Antirrhinum majus (L.) (Snapdragon)
- Jason Murray (MS, 2001) - Using Time Domain Reflectometry to Schedule Irrigation in Soilless Substrates
Awards and Honors:
- Excellence in Extension. 2010. University of Maryland Alumni Association. October, 2010. College Park, MD.
- Outstanding Extension Educator. 2009. American Society for Horticultural Science. ASHS National Meeting, July, 2009. St. Louis, MO.
- Extension Materials Award: Best Website. American Society for Horticultural Science National Conference. July, 2009. St. Louis, MO.
- American Society of Agricultural and Biological Engineers, Blue Ribbon Award: Educational Aids - Innovative Extension Methods or Impact Assessment. ASABE International Meeting, June, 2009. Reno, NV.
- Integrated Research and Extension Award of Excellence. 2009. College of Agriculture and Natural Resources, University of Maryland. May, 2009. College Park, MD.
- Northeast Region International Service Award. 2008. Epsilon Sigma Phi National Extension Honor Society. September, 2008. Indianapolis. IN.
- Northeast Region Distinguished Team Award. 2007. Epsilon Sigma Phi National Extension Honor Society. October, 2007. Charleston, SC.
- Visiting Professor. 2005. Universidad de Costa Rica, San Pedro, Costa Rica.
- ADEC Education Programs Award. 2002. American Distance Education Consortium Meeting. April, 2002. Columbus, OH.
- WebCT International Exemplary Course Award. 2001. June, 2001. Vancouver, BC. Canada.
- Teaching with Technology Award. 2001. Office of Information Technology, University of Maryland. March, 2001. College Park, MD.
- Northeast Region Distinguished Team Award. 2000. Epsilon Sigma Phi National Extension Honor Society. November, 2000. Salt Lake City, UT.
- Gold Award. 2000. Distance Education and Instructional Design Category, Educational Project. Agricultural Communicators in Education (ACE). July, 2000. US Agricultural Communicators Congress, July 2000. Washington, D.C.
- Outstanding Professional Skill Award. 2000. Agricultural Communicators in Education (ACE). US Agricultural Communicators Congress, July 2000. Washington, D.C.
- Distance Education Fellow. 2000/01. Web Initiative in Teaching (WIT). University System of Maryland. May, 2000. College Park, MD.
- Maryland State Team Award. 2000.Maryland Tau Chapter of Epsilon Sigma Phi, National Extension Honor Fraternity. March, 2000. College Park, MD.
- University of Maryland Outstanding Teacher Award. 1999. - College of Agriculture and Natural Resources, University of Maryland. May, 1999. College Park, MD.

