Emilio Gil1, Ramón Salcedo2,3, Agustí Soler4, Paula Ortega1, Jordi Llop1, Javier Campos1, Jordi Oliva5. 1. Department of Agri-Food Engineering and Biotechnology, Universitat Politècnica de Catalunya, Barcelona, Spain. 2. Department of Food, Agricultural and Biological Engineering, Ohio State University, Columbus, OH, USA. 3. Application Technology Research Unit (ATRU), Agricultural Research Service of the United States Department of Agriculture (USDA-ARS), Wooster, OH, USA. 4. Market Development EMEA, Bayer CropScience, Barcelona, Spain. 5. Field Solutions, Bayer CropScience, S.L., Barcelona, Spain.
Abstract
BACKGROUND: Leaf wall area (LWA) has been proposed as an appropriate dose expression for field testing of plant protection products (PPPs) applied via foliar spray in trellised grapes. However, its efficiency could change depending on the characteristics of the crop or the pesticide application equipment (PAE). Herein, three spray technologies were evaluated. A traditional air-assisted tractor-mounted sprayer was compared with two portable knapsack sprayers: a backpack mistblower and a backpack hydraulic sprayer. Trials were conducted in trellised wine grapes at three selected crop stages (BBCH 55, 65, 75) covering the main period of canopy development. In each canopy stage, leaf deposition and coverage were sampled for each technology. The tractor-mounted sprayer was working at 200 L ha-1 of LWA spray volume for the earliest stage and 370 L ha-1 for the other two. Three higher volume rates were used for backpack sprayers up to 800 and 1250 L ha-1 for the mistblower and the hydraulic system, respectively. RESULTS: Optimal LWA spray volumes differed among application devices in terms of efficiency and uniformity of deposition on the canopy. The efficiency of each spray application also was conditioned by the spray volume. CONCLUSION: LWA is useful for defining optimal spray volumes in trellised grapes. However, both canopy density and spray technology should be considered to assist this process. Field testing of PPPs and subsequent label recommendations should consider the relative efficiencies of corresponding experimental and conventional spray technologies.
BACKGROUND: Leaf wall area (LWA) has been proposed as an appropriate dose expression for field testing of plant protection products (PPPs) applied via foliar spray in trellised grapes. However, its efficiency could change depending on the characteristics of the crop or the pesticide application equipment (PAE). Herein, three spray technologies were evaluated. A traditional air-assisted tractor-mounted sprayer was compared with two portable knapsack sprayers: a backpack mistblower and a backpack hydraulic sprayer. Trials were conducted in trellised wine grapes at three selected crop stages (BBCH 55, 65, 75) covering the main period of canopy development. In each canopy stage, leaf deposition and coverage were sampled for each technology. The tractor-mounted sprayer was working at 200 L ha-1 of LWA spray volume for the earliest stage and 370 L ha-1 for the other two. Three higher volume rates were used for backpack sprayers up to 800 and 1250 L ha-1 for the mistblower and the hydraulic system, respectively. RESULTS: Optimal LWA spray volumes differed among application devices in terms of efficiency and uniformity of deposition on the canopy. The efficiency of each spray application also was conditioned by the spray volume. CONCLUSION: LWA is useful for defining optimal spray volumes in trellised grapes. However, both canopy density and spray technology should be considered to assist this process. Field testing of PPPs and subsequent label recommendations should consider the relative efficiencies of corresponding experimental and conventional spray technologies.
Authors: Muyesaier Tudi; Hairong Li; Hongying Li; Li Wang; Jia Lyu; Linsheng Yang; Shuangmei Tong; Qiming Jimmy Yu; Huada Daniel Ruan; Albert Atabila; Dung Tri Phung; Ross Sadler; Des Connell Journal: Toxics Date: 2022-06-19