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The number of effective herbicides available to farmers is steadily decreasing due to increasing herbicide resistance. It seems very important to address and effectively deal with the main weed management challenges (low crop yield and environmental pollution) by investigating the potential of newly introduced materials, such as biocompatible polymer-based nanoparticles. The current review aims to encourage agricultural or environmental researchers to conduct new research on the synthesis and application of modified herbicides, such as nanoherbicides, for application in weed management and to provide a comprehensive foundation on the topic. Such nanosystems could help with the promotion of the controlled release of active ingredients and extend their action time, resulting in a reduction in dose and application number; improve the physical and chemical characteristics of the herbicide to increase foliar adhesion; prevent degradation that results from environmental factors (such as sunlight, temperature, microorganisms, or pH); and decrease herbicide leaching and contamination of the environment. Furthermore, it has been indicated that some polymeric nanocarriers can penetrate biological barriers, including membranes and plant cell walls, and translocate across vascular tissues, resulting in a more efficient delivery of active ingredients. Poly(epsilon-caprolactone) is a biocompatible material that is easily decomposable by enzymes and fungi. PCL nanoparticles could be applied as nanocarriers of herbicides in agriculture due to their low toxicity, their potential for large-scale synthesis from inexpensive materials, their ability to dissolve herbicides, their high loading capacity, and their ability to help minimize the chemical decomposition of herbicides. [ABSTRACT FROM AUTHOR]

A method was developed to determine glyphosate, aminomethylphosphonic acid (AMPA), and glufosinate in soil. The worldwide use of this herbicide in agricultural activities, and its known negative effects on both the environment and health, have generated interest in the establishment of methodologies for its determination in several matrices at trace level. The development of analytical methods for the determination of glyphosate, AMPA, and glufosinate is challenging due to its present amphoteric properties, high solubility in water, low molecular weight, high affinity to the ions presents in the soil, and lack of chromophore groups in its structure, making its quantification difficult. The proposed method exhibits a linear range from 5.0 to 600 µg/kg with limits of detection of 1.37, 0.69 and 1.22 μg/kg, limits of quantification of 4.11, 2.08, and 3.66 μg/kg for glyphosate, AMPA, and glufosinate, respectively, and adequate repeatability and reproducibility (coefficients of variation <8.0% and recovery percentages between 93.56% and 99.10%). The matrix effect was calculated for each analyte, proving to be a good alternative for the determination of these contaminants. The described method was applied to 46 soil samples collected from crop fields in Hidalgo, Mexico, with concentrations varying from not detected to 4.358 μg/kg (for AMPA). [ABSTRACT FROM AUTHOR]

Brazil is the country which has produced the most coffee for over 150 years, and to achieve high productivity, pesticides are the most common control measure for pests. Due to the need to adopt less impactful control practices, natural enemies or insecticides of botanical origin have been studied as alternatives to synthetic insecticides. However, botanical pesticides can negatively affect some natural enemies, and the effect depends on the formulation and concentration. The objective of this study was to estimate the survival of green lacewing larvae, Chrysoperla externa (Hagen), exposed to different doses of neem-based products, whose active ingredient is azadirachtin (Azamax®: 0 (control treatment with distilled water), 12, 24, 36, 48, 60, 72, 84, 96, and 108 mg a.i. L−1; Organic neem®: 0, 3.3, 6.6, 9.9, 13.2, 16.5, 19.8, 23.1, and 26.4 mg a.i. L−1; Natuneem®: 0, 3.8, 7.5, 10.5, 15.0, 18.8, 22.5, 26.3, 30.0, and 33.8 mg a.i. L−1), using a parametric approach. Predator larvae were exposed to neem-based insecticides and evaluated for 20 days. Survival curves estimated by the models—Log-logistic for Azamax®, Weibull for Organic neem®, and Log-normal for Natuneem®—demonstrated an inverse relationship between increasing doses and survival time. These concluded that the application dose should be less than 84 mg a.i. L−1 for Azamax®, 19.8 mg a.i. L−1 for Organic neem®, and 26.3 mg a.i. L−1 for Natuneem® to keep 50% of the green lacewings alive for 13 days, which is the average time for the larval cycle of C. externa. [ABSTRACT FROM AUTHOR]

Mollisols are a fundamental component of global agricultural production. In the Argentine Pampas region, 65% of the Mollisols belong to Argiudoll great group. These soils have an agricultural aptitude, with limitations given mainly by varying thickness of the top horizon A as a result of the severity of water erosion depending on its site in the landscape layered on an argillic B horizon. Over the last three decades, Pampean agriculture has been widespread because of a modern technological matrix characterized by transgenic crops, and increasing use of fertilizers and pesticides. Large changes have taken place in crop sequence composition, toward the disappearance of pastures and the rapid expansion of soybean monoculture due to the upward trend of the international price of this commodity. This review contributes to an alertness regarding the significance of the soil degradation problem, in terms of decline in soil fertility and structural condition, decrease in size of soil aggregates, surface and subsurface compaction, decrease in organic carbon content, soil and water contamination, reduction of infiltration rate and structure stability, causing an increase in water losses through surface runoff and water erosion and lost ecosystem services. Additionally, a set of sustainable land management practices and legal aspects is shown. [ABSTRACT FROM AUTHOR]