Objective 3: Determine the economic and physical feasibility of precision agriculture components as they relate to farming systems.

Over the last two years much of our research has addressed disease control through irrigation management and studies on interactions between seed quality, disease, and yield or seeding rate, irrigation, and yield. Precision planters are currently available and variable rate irrigation systems have also been developed and tested by industry. In studies with both wheat and grain sorghum, we have determined that it is probably not economically justified to purchase a high dollar precision planter for wheat or grain sorghum. With wheat, we determined that seed quality has no effect on the incidence or severity of common root rot of wheat or grain yield (manuscript submitted to Plant Disease). This being the case, it is unjustified to spend significantly higher prices for high quality wheat or a precision planter to plant lower quality wheat. Likewise, with grain sorghum, the plant has a tremendous capacity to tiller and can easily compensate for low planting rates. In our studies, at a given irrigation regime, no significant differences in yield existed between widely variable planting densities (Table 1). Therefore, it becomes irrelevant whether 50,000 or 60,000 seed are planted per acre and the expense of a precision planter is not justified.

With regard to use of variable rate irrigation for disease management, we have shown conclusively that increasing the interval between irrigations can reduce incidence and severity of soilborne diseases, of different crops. In a study with take-all of wheat, increasing the irrigation interval from every week to every other week significantly decreased disease and resulted in grain yields equal to those from plots irrigated every week (Fig. 6). Similar results with sugar beets were observed in a two-year study that will be published in the January issue of Plant Disease. In both studies, irrigation interval was more important than the total amount of irrigation water applied. The variable rate irrigation equipment developed by J. R. Simplot would have been ideal for use in pathogen infested fields. However, they never considered use of the equipment for disease management and they got out of the precision irrigation business because they determined that the systems were uneconomical (Terry Tindale - Personal Communication).

Objective 4: Develop and evaluate variable rate application technology.

In August 1999, we purchased an Accu-Pulse pesticide application system from Valmont Inc. This system has potential for use in precision application of pesticides and will be modified for this purpose. It has been installed on the center pivot at Bushland and will be tested in 2000.

Objective 5: Establish an effective network for technology transfer through the AgriPartners program.

C. Education/technology transfer:

Our main effort in education transfer was through presentations at Bushland and Etter field days. Our research has been well covered by local newspapers and we have been interviewed for television news broadcasts at least four times. Dr. Rush was invited to organize a workshop on PA to be held at Purdue University February 13-15, 1999 and presentations were given at this meeting. Below is a partial listing of field days attended where presentations on our PA research program were made.

• Piccinni, G. and C.M. Rush. 1998. Effect of Different Irrigation Regimes on Sugar Beet Growth in a Pathogen-infested Field. 1998 Bushland Ag Day
• Rush, C.M., G. Piccinni, and K. Burk. 1998. Effect of Irrigation Frequency of Take-all of Wheat. 1998 Bushland Ag Day
• Rush, C.M., G. Piccinni, G.J. Michels, S. Evett, D. Upchurch, K. Burk, L. New, A. Schneider and T. Marek. 1998. Precision Irrigation for Optimizing Crop Yields in Pathogen Infested Fields. 1998 Bushland Ag Day
• Devin, R., C. M. Rush, and L. New. 1999. Irrigated wheat production with partial pet using center pivot irrigation. Agri-Partners Annual Report 1998. pp. 124.
• Michels, G.J., G. Piccinni, C.M. Rush, D.A. Fritts, and J.K. Burk. 1999. Influence of Plant Population and Irrigation Regime on Greenbug Density in Grain Sorghum: A Precision Agriculture Research Project. 1999 Bushland Ag Day Report. AREC Publication 99-31. pp. 12.
• Piccinni, G., and C.M. Rush. 1999. Application of Precision Agriculture Technology for Managing Irrigation of Drought Tolerant Corn. 1999 North Plains Research Field Ag Day Report. AREC Publication 99-18. p 40-43
• Piccinni, G. and C.M. Rush. 1999. Application of Precision Agriculture Technology for Managing Irrigation of Sorghum at Several Planting Densities. 1999 North Plains Research Field Ag Day Report. AREC Publication 99-18. p 36-39
• Piccinni, G. and C.M. Rush. 1999. Irrigation Management of Sorghum at Several Planting Densities and Drought Tolerant Corn. 1999 Bushland Ag Day Report. AREC Publication 99-31. pp. 15-16
• Rush, C.M. 1999. Reducing Losses to Take-all of Wheat by Remote Sensing and Irrigation Management. 1999 North Plains Research Field Ag Day Report. AREC Publication 99-18. p 46-48
• Rush, C.M. 1999. Reducing Losses to Take-all of Wheat by Remote Sensing and Irrigation Management. 1999 Bushland Ag Day Report. AREC Publication 99-31. pp. 9-11

D. Milestones achieved:

Our first milestone was procurement of a center pivot irrigation system from Valmont and establishment of over 600 plots to address various aspects of biotic and abiotic stress interactions (Fig. 7). We purchased remote sensing equipment and developed methods for attaching IRT radiometers to the center pivot and recording spectral information on crop stress. We also developed a remote sensing system for use in the greenhouse. Aspects of our field and greenhouse research have been published in refereed journal articles (listed below). Our research has gained the interest of state and national commodity groups as evidenced by grants exceeding $100,000. Finally, our first graduate student involved in this project, Melissa Fahnert, completed requirements for the Master of Science Degree at WTAMU and received her degree in 1999.

E. Publications:

Journal Articles:

• Harveson, R. M. and C. M. Rush. 1998. Characterization of Fusarium Root Rot Isolates from Sugar Beet by Growth and Virulence at Different Temperatures and Irrigation Regimes. Plant Disease 82:1039-1042.
• Michels, Jr., G. J., G. Piccinni, C. M. Rush, and D. A. Fritts. 1999 Sensing Greenbug (Homoptera: Aphididae) Infestations In Winter Wheat With Infrared Transducers. Southwestern Entomology 24: (in press).
• Piccinni, G., and C.M. Rush. 2000. Determination of Optimum Irrigation Regime and Water Use Efficiency of Sugar Beet Grown in Pathogen Infested Soil. Plant Disease 84: (accepted).
• Piccinni, G., C.M. Rush, K.M. Vaughn, and Lazar, M. D. 2000. Lack of Relationship Between Susceptibility to Common Root Rot and Drought Tolerance Among Several Closely Related Wheat Lines. Plant Disease 84: (in press).
• Brewton, R. G., L. Lee, and C. M. Rush. 1999. Detection of genetic diversity in beet soilborne mosaic virus (BSBMV) in the central United States; identification of single-strand conformation polymorphisms (SSCP). In: The American Society of Sugar Beet Technologists Proceedings from the 30th Annual Meeting - Agriculture. Pages 205-209.
• Piccinni, G., J. M. Shriver, and C. M. Rush. 2000. The relationship between seed size, planting date, and common root rot in hard red winter wheat. Plant Disease 84: (submitted).
• Shriver, J.M., C.M. Rush, and B.A. Stewart. 1999. The effect of seed size and planting date on common root rot in wheat grown in the Texas Panhandle. WTAMU Div. of Ag. Res. Report. 1999-2

Abstracts:

• Burk, J.K., T.W. Proffitt, G. Piccinni, G.J. Michels, and C.M. Rush. 1998. Development of an Automated System for Infrared Detection of Plant Stress in Greenhouse Studies. Phytopathology 88:S12
• Fahnert, M.L., G. Piccinni, C.M. Rush, and L.L. New. 1998. Effects of different irrigation regimes on sugar beet growth in a pathogen infested field. Phytopathology 88:S27
• Piccinni, G. and C.M. Rush. 1998. Water use efficiency and disease severity of sugar beet grown in pathogen-infested soil. Phytopathology 88:S71
• Brewton, R. G. and C. M. Rush. 1999. Detection of genetic diversity in beet soilborne mosaic virus (BSBMV) in the central United States; identification of single-strand conformation polymorphisms (SSCP). American Society of Sugar Beet Technologists Proc. 36:54
• Piccinni, G., M. L. Fahnert, and C. M. Rush. 1999. Management of soilborne pathogens by managing irrigation of sugar beet. American Society of Sugar Beet Technologists Proc. 36:84
• iccinni, G. and C. M. Rush. 1999. Implementation of precision agriculture technology for disease management. The American Phytopathological Society – Pacific Division. (In Press)
• Piccinni, G. and C. M. Rush. 1999. Water use efficiency and disease severity of sugar beet grown in pathogen-infested soil. American Society of Sugar Beet Technologists Proc. 36:85
• Rush, C. M., G. Piccinni, and J. K. Burk. 1999. Development of a disease management system using precision agriculture technology. American Society of Sugar Beet Technologists Proc. 36:89
• Piccinni, G., J. K. Burk, C. M. Rush, and J. G. Michels. 1999. Development of an automated system for infrared detection of plant stress. Agronomy Abstracts 1999: 109.

F. Precision agriculture proposals submitted or funded:

1998

• Effect of soil moisture on Aphanomyces root rot & Rhizomania - Beet Sugar Development Foundation - $5,390.
• Application of Precision Agriculture Technology for Managing Irrigation of Sorghum at Several Planting Densities. Texas Grain Sorghum Board - $15,000.
• Application of Precision Agriculture Technologies for Irrigation of Sugar Beets in Pathogen Infested Soil - 1998 Sugar Beet Research. Western Sugar Research Committee - $21,000
• Application of Precision Agriculture Technologies for Position specific irrigation in pathogen infested soils. Texas Faculty Development Program - $95,000
• Proposal to Develop Integrated Control of Sorghum Ergot. USDA/CSREES/NRE - $30,000.
• Use of Precision Agriculture Technologies for control of Cotton Root Rot. Texas State Support Committee - $35,000.
• Application of Precision Agriculture Technologies for Irrigation of Sugar Beets in Pathogen Infested Soil - 1998 Sugar Beet Research. Holly Grower Research Committee - $21,000
• Application of Precision Agriculture Technology for Managing Irrigation of Drought Tolerant Corn. Texas Corn Producers Board - $15,000.
• Precision Application of Pesticides. Valmont Irrigation - $15,000.
• Development of an ?On Site? Integrated Pest management/Precision Agriculture Graduate Training Program. IGRET Pre-proposal– $1,725,842

1999

• Reducing losses to take-all of wheat by remote sensing and irrigation management. Texas Wheat Producers Board - $12,000.
• Ecology and epidemiology of wheat streak mosaic virus and High Plains disease of wheat. Texas Wheat Producers Board - $12,000.
• Application of precision agriculture technology for managing irrigation of drought tolerant corn. Texas Corn Producers Board - $15,000.
• Application of precision agriculture technology for managing irrigation of sorghum at several planting densities. Texas Grain Sorghum Board - $15,000.
• Optimization of crop water use efficiency in pathogen infested soils. USDA-NRI-Competitive Grant Program - $456,926.
• Population diversity and potential virulence of beet soil borne mosaic virus. USDA-NRI-Competitive Grant Program - $424,723.
• Remote sensing for detection and differentiation of biotic and abiotic stresses. USDA-Southern Region IPM - $99,864.
• Precision application of pesticides using the Valmont ACCU-PULSE chemigation system. Valmont - $10,000.
• Management of disease caused by soilborne plant pathogens. Resource21 - $6,000.
• Development of a variable rate irrigation-chemigation system for center pivots. THECB - ATP - $291,500.

G. Precision Agriculture meetings attended/papers (posters) presented:

During the last two years, we attended numerous meetings concerning precision agriculture. At each of these with the exception of the International Conference on Precision Agriculture, we presented at least one paper on our PA research. These were all published in various journals and proceedings and are listed in the publication section for abstracts above.

• Attended the 44th Annual Conference on Control of Soil Fungi (Precision Agriculture Session), Santa Maria, CA, March 31, 1998
• Attended the International Conference on Precision Agriculture, St. Paul, MN, July 20, 1998.
• Program Chair. Precision Agriculture. 17th Eastern Regional Conference on the Ecology of Root-Infecting Microorganisms (ERCERIM – 17) West Lafayette, Indiana, March 14-16, 1999.
• Piccinni, G. and C. M. Rush. 1999. Use of remote sensing and variable rate irrigation for management of take-all in hard red winter wheat. 17th Eastern Regional Conference on the Ecology of Root-Infecting Microorganisms, West Lafayette, Indiana, March 1999.
• Rush, C. M. and G. Piccinni. 1999. Rhizomania of Sugar Beet: Interactions between BNYVV, BSBMV, and Irrigation management. 17th Eastern Regional Conference on the Ecology of Root-Infecting Microorganisms, West Lafayette, Indiana, March 1999.

H. Other developments

For the most part, we made significant progress on each of our objectives during the first two years of this program. We also addressed new research areas (not included in our original objectives) in virus epidemiology, using some of the tools of precision agriculture such as GPS units and GIS computer software for mapping genomic variability in virus populations. However, we did have some problems and setbacks. These were primarily associated with equipment procurement and data analysis. The variable rate irrigation system that we had negotiated for with J. R. Simplot was never delivered. I believe that if I had continued private negotiations, I would have had better luck, but when we attempted to enlarge our association by including additional personnel and projects Simplot became more cautious and eventually backed out. Ultimately, they dropped their project with variable rate irrigation equipment and got out of the business but their system would have been an excellent research tool to demonstrate the potential for managing disease with precision application of irrigation.

We also had problems getting timely data analysis from Resource 21, with whom we established a cooperative project. They over flew our research plots weekly in 1998 but we only received spectral images long after harvest when the data was no longer as useful. We experienced similar analysis problems with the IRT data we collected from the center pivot. Originally, Dan Upchurch, USDA-ARS in Lubbock was generating maps for us but was unable to continue this level of cooperation when he took on the responsibilities of Laboratory Director of the new stress lab. We attempted to purchase software from the same company but found it was only available in an Apple format. The company attempted to help us by developing new software but the final product was never satisfactory. Additionally, we found that the IRT transducers we were using on the pivot were more sensitive than expected. They were not really suitable for the rugged treatment to which they were exposed and their accuracy greatly diminished after only one year of field use.

Through these difficulties, we learned valuable lessons about dealing with industry, how to set up future experiments, and the type of information we can realistically expect to provide to farmers in the near future. Each failure or problem we experienced in our research is one that farmers in our area can now easily avoid, thereby saving both time and money.