Assessing glyphosate in water, marine particulate matter, and sediments in the Lagoon of Venice

Lagoon water, suspended particulate matter, and sediment samples from seven sites at Lagoon of Venice were collected from 2019 to 2021 in order to study the presence of the herbicide glyphosate (N-(phosphonomethyl)glycine), among the most widely used agricultural chemicals worldwide, but its occurrence in lagoon water environment has not been deeply investigated. The sites were selected considering a supposed diversity of inputs and of pollution levels. An analytical method based on ion chromatography coupled with tandem mass spectrometry was optimized and validated for lagoon water, marine particulate matter, and sediment samples. Maximum concentrations of glyphosate were 260 and 7 ng L−1 for lagoon water and suspended particulate matter, respectively, and 15 ng g−1 for sediment, with some spatial and temporal fluctuations. Our results demonstrate that glyphosate content in the Venice Lagoon mainly depends on external forcing from river inlets and agricultural lagoon activities.

Production Risk and the Early Adoption of Alternatives to Antibiotics: Evidence From Poultry Farmers in China

Excessive or unreasonable use of agricultural chemicals has caused a wide range of negative effects on the environment and residents' health. It is urgent to promote the reduction of the use of agricultural chemicals. Taking the use of veterinary antibiotics (hereafter antibiotics) in broiler breeding as an example, based on the data of 380 contract farmers, this paper first investigated the effects of production risk on farmers' decision-making on the use of alternatives to antibiotics and the amount of antibiotics in the initial stage of alternatives entering into the market. The results show that: (1) the fluctuation of mortality in the lag period has no significant influence on the adoption of alternatives, and farmers are concerned about the absolute or average level of mortality in the lag period. (2) The mortality rate lagged three phases had a significant positive impact on the adoption of alternatives. On average, the mortality rate lagged three phases increased by 0.01, and the likelihood of farmers adopting substitutes in the early stage increased by 0.670%. (3) The production risk plays an important role in regulating the effects of alternatives. When using alternatives, the mortality rate of lagging three phases is higher, the higher the dosage of antibiotics and the lower the mortality rate in the early stage, suggesting that higher production risk would result in using alternatives for the purpose of reducing the production risk rather than reducing the use of antibiotics. Thus, to realize the effect of alternatives in reducing agricultural chemicals, the prerequisite is to improve the production risk management ability of farmers.

Potassium phosphite enhances the antagonistic capability of Bacillus amyloliquefaciens to manage tomato bacterial wilt

Bacterial wilt caused by Ralstonia solanacearum is a distributed and worldwide soil-borne disease. The application of biocontrol microbes or agricultural chemicals has been widely used to manage tomato bacterial wilt. However, whether and how agricultural chemicals affect the antagonistic ability of biocontrol microbes is still unknown. Here, we combined potassium phosphite (K-Phite), an environmentally friendly agricultural chemical, and the biocontrol agent Bacillus amyloliquefaciens QPF8 (strain F8) to manage tomato bacterial wilt disease. First, K-Phite at a concentration of 0.05% (w/v) could significantly inhibit the growth of Ralstonia solanacearum. Second, 0.05% K-Phite enhanced the antagonistic capability of B. amyloliquefaciens F8. Third, the greenhouse soil experiments showed that the control efficiency for tomato bacterial wilt in the combined treatment was significantly higher than that of the application of B. amyloliquefaciens F8 or K-Phite alone. Overall, our results highlighted a novel strategy for the control of tomato bacterial wilt disease via application and revealed a new integrated pattern depending on the enhancement of the antagonistic capability of biocontrol microbes by K-Phite.

Influences of Organic Volatile Compounds on the Secondary Organic Carbon of Fine Particulate Matter in the Fruit Tree Area

Three combined investigations were conducted to examine the sources of PM2.5 in agricultural areas. The first was the measurement of PM2.5 and gaseous compounds in the greenhouse, which is a relatively closed system, while the second was the analysis of pesticide components used in agricultural areas. Finally, the physical and chemical properties of PM2.5 were analyzed in an orchard area and compared with the results of the greenhouse and agricultural chemical analyses. As a result, this research was able to confirm the source of emission and characteristics of PM2.5 originating from the agricultural area. Volatile organic compounds (VOCs) in agricultural areas are emitted by agricultural chemicals, and the discharged agricultural chemicals are first absorbed into the soil, and then released into the air by evaporation. Finally, the secondary products of PM2.5 in agricultural areas were estimated to have positive relationships with the VOCs from agricultural chemicals, and NH3 from fertilizers. The photochemical reactions of VOCs and NH3 were responsible for the impact on secondary products.

Agrochemical Usage Inventory and Measured Residues in Streams Within an Off-Season Durian Production Region of Thailand

Rising demand for off-season durian production in Thailand has led to increased agrichemical use and potential environmental and health concerns. In this study, we surveyed 117 farmers and collected water samples from 11 villages in Krungching Sub-district. Overall, 108 agrochemicals were listed as being used in off-season durian production, but we focused on residual concentrations of the persistent herbicides glyphosate and paraquat in surface water. We applied a pollution release and transfer registry for 2016 to determine an application rate of 288,149 kg/year for these agrichemicals. These were primarily detected during the dry season, and not the wet season. This reporting system can be used to develop seasonal environmental surveillance and monitoring tools for more sustainable use of agrochemical substances in off-season durian production in environmentally sensitive areas such as the Krungching River watershed, especially during the first stage of cultivation (dry season), in order to ensure the use of agricultural chemicals under appropriate circumstances. Further studies are needed to better understand the full diversity of persistent agrochemical substance usage and disposal, in order to reorient agricultural activities to focus on local needs and capabilities as part of efforts to implement more sustainable agriculture in Thailand.

2021–2022 Florida Citrus Production Guide: Best Management Practices for Soil-Applied Agricultural Chemicals

Reviewed March 2021. There are no changes in recommendation from 2020.