Application of agricultural pesticides is very inefficient; a large proportion of the chemical does not reach the intended insect, weed or disease target and enters the environment as non-point source pollution. This project tests a new way to formulate pesticides such that less chemical is wasted during the application process. As a consequence less chemical will need to be applied for a given level of efficacy so there will be less to enter the environment as pollution. A second consequence will be reduced production cost of the chemical. OBJECTIVES: This project is a feasibility study to confirm that we can formulate pesticides such that they are biologically more efficient. We will develop and validate a device and process for formulating pesticides that will increase their biological efficiency at least two-fold. We will build this device and license it to pesticide manufacturers for a revenue-based royalty. The method promises to make pesticides less expensive to manufacture as well as increase the efficacy per unit mass of chemical. To determine the feasibility we will test the following four hypotheses: Hypothesis 1: There is an optimum particle size distribution that maximizes the efficacy of a water insoluble active ingredient applied by hydraulic nozzle. Hypothesis 2: The optimum size distribution of a water insoluble active ingredient that maximizes efficacy reduces the amount (mass) of active ingredient required for pest control by a factor of two to five compared to the standard formulation. Hypothesis 3: The optimum size distribution of a water insoluble active ingredient that maximizes efficacy reduces the knockdown time compared to the standard formulation. Hypothesis 4: The optimum size distribution of a water insoluble active ingredient that maximizes efficacy reduces off-target drift compared to the standard formulation. APPROACH: Experiments will use a high concentration wettable powder formulation of deltamethrin as the control against which we will compare three deltamethrin Extended Powders (EPs). The EPs will be separated from the parent (Decis 80WP) using a patented Vortak separator. The three particle size distributions will be: Large fraction (mean larger than the parent, variance the same as or less than the parent); Medium fraction (mean approximately the same as the parent, variance less than the parent); Small fraction (mean and variance both less than the parent). All four treatments (Parent WP and three EPs) will be sprayed using a contained track sprayer onto beans and artificial diet. Insects (2nd instar Spodoptera exigua) will be exposed for timed increments up to 36 hours, in accordance with industry protocols for knockdown and mortality testing of AIs and formulations. Assessment of the four treatments will be by a standard insecticide efficacy trial employing probit analysis of the four treatments at three application rates. Two parameters will be estimated from the mortality data: LD95, the least amount of chemical required for 95% mortality, and KT95, the time required (knockdown time) to achieve 95% mortality. Drift will be estimated using a proprietory drift model with measured size distributions of the parent WP and the three EPs as input. Further experiments will be conducted using other pesticides as time and money permits
