Location:2009 Annual Report
1a. Objectives (from AD-416)
1) Improve existing aerial application technologies to maximize efficiency and biological efficacy of crop production and protection compounds with minimal spray drift and impact to non-target systems. Subobjective 1A: Develop and implement standard procedures for evaluating drift reduction technologies (DRTs) and assessing biological impacts of sprays in crop canopies. Subobjective 1B: Develop and optimize the use of autonomous unmanned aerial vehicles (UAVs) for pest control. Subobjective 1C: Assess biological impacts of spray drift. 2) Develop remote sensing and variable rate aerial application systems that enhance detection, prevention, and control of plant diseases, nutritional deficiencies, or insect damage in annual and perennial crops. Subobjective 2A: Characterize spatial variability of crop conditions using multispectral imaging to develop treatment maps for use with site-specific aerial application systems. Subobjective 2B: Integrate remote sensing and variable rate aerial application technologies to optimize crop management strategies. Subobjective 2C: Develop sensors that rapidly and/or remotely detect pest presence, crop condition, spray droplets, and volatile organic compounds. Subobjective 3D: Adapt autonomous unmanned aerial vehicles (UAVs) for remote sensing of crop conditions. 3) Develop, enhance, and implement decision support systems that improve user ability to select and operate application equipment and schedule spray treatments that optimize biological efficacy. Subobjective 3A: Correlate aerial spray dispersion model estimates with off-target biological effects and in-swath deposition. Subobjective 3B: Develop and implement crop growth and management decision systems to optimize aerial applications.
1b. Approach (from AD-416)
Utilizing engineering and biological principles, laboratory and field studies will be conducted to evaluate the effects of various aerial application parameters, such as spray formulation and droplet size spectrum, on aerial application efficiency and biological efficacy. Efforts will focus on the integration of remote sensing and variable rate application systems to maximize the efficacy of crop production materials while minimizing any off-target impact from these sprays. Decision support systems will be developed that help applicators, farmers, and crop consultants in making the correct treatment decisions to protect a crop from pests. This project will develop and implement new and improved aerial application technologies for safe, efficient, and sustainable crop production and protection.
3. Progress Report
Work under this project during FY 2009 resulted in significant progress in improving the efficacy of crop production and protection materials, enhancing the use of remote sensing and precision application in crop production systems, and spray droplet movement modeling. Tests were conducted in high-speed and low-speed wind tunnels to determine the levels of spray drift mitigation from a number of spray nozzles and formulations. These projects support the EPA Drift Reduction Technology Program. The Unmanned Aerial Vehicles (UAV) and other USDA-owned aircraft were fitted with multispectral cameras to take airborne images of crops and to locate and identify weeds and disease states in corn, cotton, and sorghum fields, and in pecan groves. Project scientists characterized the deposition and efficacy of aerial applications of glyphosate (a broad-spectrum herbicide) on broadleaf and grassy weeds when applied at two different spray rates and droplet sizes with conventional hydraulic nozzles, rotary atomizers, and electrostatic nozzles. Aerial applicators will be able to use this information to select aerial nozzles that will allow them to achieve maximum efficacy. For detection of spider mites on cotton, GreenSeeker™ technology was evaluated to detect differences between uninfested and heavily-spider mite-infested cotton. Project scientists continue to routinely serve as experts in the aerial application industry and were sought out for advice and consultation by industry and academic research personnel; and by officials with the EPA, Dept. of Homeland Security, Dept. of Defense, USDA-APHIS, and numerous State representatives from around the nation.
1. Improved spray drift reduction technologies: With increasing environmental awareness and associated concerns with potential off-target movement of applied crop protection products, aerial applicators will soon be facing pesticide label enforced buffer zones. These buffer zones potentially reduce the treatable area of crop production fields by requiring field-edge strips that remain untreated in an effort to increase the downwind distance from the application swath to the field edge. New technologies are needed that will reduce spray drift from aerial and ground application as compared to conventional application systems. In cooperation with the U.S. EPA Office of Pesticide Programs, project scientists provided definitive assessments of protocols that can be used to test potential drift reduction technologies (DRTs). The work also involved both low- and high-speed wind tunnel testing protocols for ground and aerial DRTs, including assessments of various spray nozzles and the droplet sizes produced. This accomplishment is critical in providing the aerial application industry with scientifically sound information, protocols, and new technology to assure ongoing compliance with evolving regulatory requirements.
2. Airborne imaging system detects root rot in cotton fields: Project scientists integrated a multispectral camera with specifically designed camera control to develop a cost-effective airborne remote sensing system for detection of disease states/pest infestations in growing crops. The system consistently produced precise and easily interpretable images of the seasonal spread of root rot in a commercial cotton field. Through the rapid identification of this disease from an aerial platform, the area could be treated to limit the crop damage. This accomplishment is important because it provides new technology for more efficient detection and assessment of disease/pest infestation states in important U.S. crops, which will greatly aid aerial applicators in protecting crops in an environmentally sensitive manner.
3. New spray nozzles improve herbicide application efficiency: The broad-spectrum herbicide glyphosate is widely used for weed control in genetically engineered glyphosate-resistant crops such as cotton, corn, and soybeans. Due to the rising cost of glyphosate, aerial applicators need new spray technologies that will allow them to optimize the efficiency of spray applications so that effective weed control can be achieved with a minimum amount of glyphosate required. Project scientists developed definitive deposition/efficacy information on glyphosate sprays applied through conventional hydraulic nozzles, as compared to new rotary atomizer and electrostatic nozzle technology. The work clearly showed that the new nozzles are superior in many respects, including increased herbicide efficacy, and reduced amounts of liquid spray required which permits significant reduction in aircraft energy consumption and application time. These benefits result in lowering of application costs and enhancement in environmental sensitivity.
4. Multispectral optical sensor detects spider mite damage in cotton: Spider mites have become key pests of cotton and can completely defoliate a crop, but recent advances in portable optical sensors may provide a tool that growers and crop consultants can use to combat this menace. The GreenSeeker Handheld Optical Sensor was used to detect and quantify spider mite damage in cotton. The sensor accurately detected mite damage within three days of mite infestation. Validation of the efficacy of the Sensor in detecting and monitoring mite damage in cotton, accomplished by this work, provides crop consultants, growers, and others with a relatively low-cost and highly portable instrument to detect spider mite infestations in cotton fields and make the appropriate spray application to limit the damage to the crop from the mites. Information provided by the Sensor will permit use of site-specific control measures that target only appropriate areas within the larger field, which will improve control efficiency, minimize costs, and minimize environmental effects.
Hoffmann, W.C., Fritz, B.K., Lan, Y. 2009. Evaluation of a proposed drift reduction technology high-speed wind tunnel testing protocol. Journal of ASTM International. 6:doi:10.1520/JAI102122.