The objective of this study was to identify the main sources of variation in pesticide losses at field and catchment scales using the dual permeability model MACRO. Stochastic simulations of the leaching of the herbicide MCPA (4-chloro-2-methylphenoxyacetic acid) were compared with seven years of measured concentrations in a stream draining a small agricultural catchment and one year of measured concentrations at the outlet of a field located within the catchment. MACRO was parameterized from measured probability distributions accounting for spatial variability of soil properties and local pedotransfer functions derived from information gathered in field- and catchment-scale soil surveys. At the field scale, a single deterministic simulation using the means of the input distributions was also performed. The deterministic run failed to reproduce the summer outflows when most leaching occurred, and greatly underestimated pesticide leaching. In contrast, the stochastic simulations successfully predicted the hydrologic response of the field and catchment and there was a good resemblance between the simulations and measured MCPA concentrations at the field outlet. At the catchment scale, the stochastic approach underestimated the concentrations of MCPA in the stream, probably mostly due to point sources, but perhaps also because the distributions used for the input variables did not accurately reflect conditions in the catchment. Sensitivity analyses showed that the most important factors affecting MACRO modeled diffuse MCPA losses from this catchment were soil properties controlling macropore flow, precipitation following application, and organic carbon content.
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Acta Trop
December 2024
Centro de Investigación en Alimentación y Desarrollo, A. C. (CIAD), 83304 Hermosillo, Sonora, Mexico. Electronic address:
Int J Food Microbiol
December 2024
National Key Laboratory of Tropical Crop Breeding, School of Tropical Agriculture and Foresty, Hainan University, Haikou 570228, Hainan, China. Electronic address:
During storage and transportation, fruits and vegetables are susceptible to various pathogens, leading to quality degradation and significant economic losses. Currently, chemical pesticides are primarily used for control; however, their overuse poses serious threats to human health and causes environmental pollution. Biocontrol, known for its environmentally friendly characteristics, has been extensively studied.
View Article and Find Full Text PDFFront Insect Sci
December 2024
USDA-ARS Southern Insect Management Research Unit, Stoneville, MS, United States.
Soybean looper (SBL), (Walker 1858) (Lepidoptera: Noctuidae), is one of the most damaging insect pests of soybean, (L.) Merr., in the mid-south region of the United States, and causes significant economic losses to cotton, sunflower, tomato, and tobacco crops in the United States, Brazil, and Argentina.
View Article and Find Full Text PDFPest Manag Sci
December 2024
College of Plant Protection, Henan Agricultural University, Zhengzhou, China.
Background: Peanut stem rot, caused by Sclerotium rolfsii, has become increasingly prevalent in China, leading to significant yield losses in peanut production. To effectively manage peanut stem rot, we assessed the potential application of difenoconazole against peanut stem rot.
Results: Difenoconazole has a good inhibitory effect on the mycelial growth of S.
J Agric Food Chem
December 2024
College of Plant Protection, Northwest A&F University, Yangling 712100, Shaanxi, China.
Nitrogen-containing heterocycles have attracted attention for the development of chemicals because of their many types, high physiological activities, and ease of synthesis. Aphids are severe pests found worldwide that cause serious losses in crop yield and quality every year. In this study, a series of novel dienolone thiazole derivatives were synthesized using dienolone acetate as the parent molecule.
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