Herbicides In Soil Research Articles

EFFICIENCY OF APPLICATION OF SOIL HERBICIDES ON SUNFLOWER CROPS

The selection of the optimal scheme for the protection of sunflower crops is always relevant, since the protection of crops from weeds is very important and has a direct impact on the productivity of the crop. The goal is to determine the effect of soil herbicides on weediness of sunflower crops. Determining the effectiveness of various options for herbicide protection. Applied materials and methods: field experiment, laboratory, analysis, processing and generalization of data. The results of the application of different options of herbicide protection on the yield of sunflower of the right-bank forest-steppe of Ukraine are presented. It was determined that the experimental plots had a small-year type of weeding and an average degree of weeding. Among chemical protection, the best efficiency was recorded when using the soil herbicide Challenge at the rate of 5 l/ha, the efficiency compared to the control was 86.7%. It is worth noting that the efficiency of the reference herbicide Primekstra TZ Gold at the rate of 4.5 l/ha was 69.7%. The level of destruction of segetal vegetation on other variants of herbicide use ranged from 65.8% to 78.9% 14 days after application. The use of the drug Challenge at the rate of 2.5 l/ha in combination with Prometrex, Racer and Aspect Pro showed average efficiency and ranged from (61.0 to 55.3%). A decrease in the application rate of the drug Challenge - 2.5 l/ha in tank mixtures led to the growth of dicotyledonous weeds. It was established that the highest yield of 3.8 t/ha has the option of using the soil herbicide Challenge with a rate of 5.0 l/ha. In comparison with the control, an increase of 0.6 t/ha is recorded. A significantly lower level of sunflower productivity was obtained with the introduction of tank mixes Prometrex - 1.5 l/ha + Aspect Pro - 2.0 l/ha and Racer - 1.5 l/ha + Aspect Pro - 2.0 l/ha. A promising direction for further research is the study of the impact of herbicide protection on sunflower productivity and the effectiveness of segetal vegetation.

Eriochloa villosa in the Primorsky Territory of Russia and the search for soil herbicides to combat it in soybean crops

The work analyzes the results of monitoring the weed field flora of the Primorsky Territory. A tendency has been revealed to increase the occurrence and density of the woolly cupgrass Eriochloa villosa (Thunb ex Murray.) Kunth, which is difficult to control due to a number of competitive biological advantages and morphological features that determine its resistance to many herbicides. In experiments conducted in 2021–2022. in the Far Eastern Scientific Research Institute of Plant Protection, it was revealed that according to the main indicator -a decrease in the wet above-ground mass of experimental weed plants compared to the control, the most effective herbicides were Dual Gold 1.6 l/ha, Proponit 3.0 l/ha and tank mixtures Dual Gold 1.5 l/ha + Gesagard 2.5 l/ha, Dual Gold 1.5 l/ha + Zenkor Ultra 0.5 l/ha, Dual Gold 1.5 l/ha + Command 0.7 l/ha.

МЕРЫ БОРЬБЫ С СОРНОЙ РАСТИТЕЛЬНОСТЬЮ НА ПОСЕВАХ СОИ

In the forest-steppe zone of the Republic of North Ossetia-Alania on soybean crops (Iriston varieties), the effect of the soil herbicide Harness and insurance herbicides Galaxy Top, Illoxan, Frontier was studied. The aim of the research was to study the effect of various herbicides on the contamination of crops and the species composition of weed vegetation of promising soybean varieties in the conditions of the forest-steppe zone of the Russian Federation. Scientific novelty of research. The influence of various herbicides on the growth, development and productivity of promising soybean varieties has been studied; the effect of herbicides on the contamination of crops has been shown; The removal of basic nutrients by individual species of weeds has been established. Every year, more and more new herbicides appear on the market, so studying the properties of herbicides and their effect on weeds is an urgent task. The methodology. On the leached chernozems of the forest-steppe zone of the Russian Federation-Alania in 2020-2022, on the experimental fields of the SCNIIGPSH VNC RAS. The sowing method is wide–row (row spacing – 45 cm), with a seeding rate of 400 thousand germinating seeds per 1 hectare. The research area is hot, mostly well-humidified. The sum of temperatures is 3000-3200 °C. The climate of the described territory is continental, the absolute annual amplitude of air temperature fluctuations is 64 ° C. On the territory of the experiment, the soil is represented by medium-sized, heavy-loamy leached chernozem, underlain by pebbles. The soil is mechanically loamy, with a depth that turns into light and medium loamy- rocky. The authors found that chemical protection of crops from weeds in the forest-steppe zone should be carried out with combinations of herbicides Pivot 0.9 + Bazagran 1.1. At the same time, weed death reaches from 79.4 to 92.9%. After harvesting soybeans, the soil is quite suitable for the cultivation of any agricultural crop, since (in specified doses) herbicides do not accumulate in products and are safe for the environment.

Assessing the effect of organic amendments on the degradation of profoxydim in paddy soils: Kinetic modeling and identification of degradation products

The fate and behavior of herbicides can be altered in an unpredictable way when organic amendments are added to soil as a beneficial management tool. The objective of this work was to investigate the effect exerted by the addition of two different organic amendments (alperujo compost and biochar) to soil in the degradation of one of the most relevant new generation rice herbicides, profoxydim. In unamended soils, the degradation of profoxydim was quite fast and was governed by both chemical (DT50steril soil = from 1.52 to 9.21 days) and microbial (DT50nonsterile soil = from 0.47 to 0.53 days) processes.Alperujo- and biochar-amended soils significantly increased the persistence of the herbicide in both soils, especially in the presence of biochar, due to the high capacity absorption of this amendment, increasing DT90 from 1.92 to 3.54 days for DT90unamended to 41.02–48.41 days for DT90biochar amended. Different kinetics models applied to fit the observed dissipation datasets showed that a HS biphasic model fits well with the dissipation of profoxydim in amended and unamended soils.For the first time, five degradation products (DPs) were identified by HPLC-QTOF-MS/MS in soil and a degradation pathway was described. Main DP was generated via oxidation of the sulfur atom to give rise to the corresponding sulfoxide derivative, with this DP being more persistent than the active substance.These outcomes can be very useful for the assessment of the environmental risk associated with the use of profoxydim in rice crops and the application of organic amendments as potential measures for minimizing the risk of contamination of natural water resources.

Reduced irrigation impact on soil-applied herbicide dissipation and rotational crop response

Abstract Soil-applied herbicides are important for controlling weeds in many crops but risk damage to susceptible rotational crops if they persist. Field studies were conducted in Powell, WY, from 2015 through 2017 to evaluate the effect of reduced water availability on soil-applied herbicide dissipation. Eight soil-applied herbicides, applied to dry bean or corn, were exposed to three season-long irrigation treatments (100%, 85%, and 70% of estimated crop evapotranspiration [ETc]) by overhead sprinkler. Soil samples were collected to a depth of 10 cm from 0 to 140 d after application, and soil herbicide concentrations were quantified using gas or liquid chromatography and mass spectrometry. Herbicide concentrations were regressed over time to produce a soil half-life estimate for each herbicide and irrigation treatment. Reduced irrigation decreased dry bean yield by up to 77% and corn yield by up to 50%. After adjusting for precipitation, the lowest irrigation treatment received 78% and 76% as much water as the full irrigation treatment in 2015 and 2016, respectively. This significantly increased the soil half-life of imazethapyr but did not increase the soil half-life of atrazine, pyroxasulfone, saflufenacil, ethalfluralin, trifluralin, or pendimethalin. Reduced irrigation did not increase carryover injury to rotational crops from these herbicides 1 yr after application. Instead, carryover response was determined by the inherent persistence of individual herbicides. Imazethapyr (0.1 kg ai ha−1) injured rotational sugar beet, and isoxaflutole (0.1 kg ai ha−1) injured rotational dry bean. Pyroxasulfone (0.2 kg ai ha−1), atrazine (2.0 kg ai ha−1), saflufenacil (0.1 kg ai ha−1) + dimethenamid-P (0.6 kg ai ha−1), ethalfluralin (0.8 kg ai ha−1), trifluralin (0.6 kg ai ha−1), and pendimethalin (1.1 kg ai ha−1) did not injure rotational crops regardless of irrigation treatment. Drought stress sufficient to cause up to 77% crop yield loss did not increase soil-applied herbicide carryover.

Magnetic porous carbon material derived from imine-linked covalent organic frameworks for magnetic solid phase extraction of trace chlorine-containing herbicides in soil

Here, imine-linked covalent organic frameworks coated Fe3O4 microspheres were fabricated and employed as the self-template to prepare magnetic porous carbon material. The magnetic solid phase extraction (MSPE) performance of such magnetic covalent organic frameworks derived porous carbons (CMCOFs) were studied for the first time, and the improved MSPE performance was verified. The variations of chemical and material properties in the carbonization processes were studied, and it was found that the CMCOFs carbonated at 400°C exhibited highest adsorption efficiencies for chlorine-containing herbicides due to the formation of nitrile components at this stage. The CMCOFs retained high adsorption efficiencies (above 90 %) to chlorine-containing herbicides at wide pH range (3–12) and high salt concentration. The CMCOFs-based MSPE coupled with HPLC technique was in good potential for analysis of trace chlorine-containing herbicides in soil samples. Under the optimized conditions, this approach displayed short extraction and elution time (5 and 8 min) and low limits of detection (0.35–5.5 ng/mL) for chlorine-containing herbicides. The recoveries of spiked analytes and the relative standard deviations in real soil samples were 81.86 %–110.9 % and less than 5.92 %, respectively. This study provides an efficient method for the analysis of trace chlorine-containing herbicides in complex samples, as well as give some inspiration on material modulation by controlled carbonization to achieve improved sorption performances.

Spatial distribution and ecological-health risks associated with herbicides in soils and crop kernels of the black soil region in China

Herbicides are vital inputs for food production; however, their associated risks and hazards are pressing concerns. In black soil, the cumulative toxic effects of compound herbicides and potential risks to humans are not yet fully understood. Thus, this study conducted a comprehensive investigation to assess herbicide residue characteristics and the associated ecological health risks in representative black soil regions where major food crops (maize, soybean, and rice) are cultivated. Findings revealed that the soil harbored a collective presence of 29 herbicides, exhibiting total concentrations ranging from 111.92 to 996.14 μg/kg dry weight (dw). This can be attributed to the extensive use of herbicides over the years and their long half-lives, which results in the accumulation of multiple herbicide residues in the soil. Similarly, the total herbicide levels in maize, soybean, and rice kernels were 1173–61,564, 1721–9342, and 3775–8094 ng/kg dw, respectively. Multiple herbicide residues at all monitored sites were attributed to continuous crop barriers in soybean fields and the adoption of soybean and maize crop rotations. Notably, herbicides pose ecological risks in the black soil region, exhibiting high-risk levels of 79 %, 24 %, and 14 % at the sites monitored for oxyfluorfen, clomazone, and butachlor, respectively. Carcinogenic atrazine exhibited low- and medium-risk levels in 34 % and 63 % of soil samples, respectively. These results can serve as a scientific basis for establishing herbicide residue thresholds in agricultural soils within black soil areas and for implementing effective control measures to prevent herbicide contamination in agricultural ecosystems.

Ultrasound-assisted extraction followed by liquid chromatography coupled to tandem mass spectrometry for the simultaneous determination of multiclass herbicides in soil.

An analytical methodology based on ultrasound-assisted extraction (UAE) followed by liquid chromatography coupled to tandem mass spectrometry (LC-MS/MS) has been developed for the identification and quantification of 9 authorized herbicides in soil (dimethenamid-P, imazamox, S-metolachlor, nicosulfuron, pendimethalin, prosulfuron, bentazone, terbuthylazine, and mesotrione). Preliminary experiments dealing with solvent extraction, theextraction technique, and herbicide response comparison in soil, with and without organic amendments, were carried out with the purpose of obtaining high sample throughput and sensitivity. UAE and thesolvent mixture water:methanol demonstrated higher efficiency and they were selected as sample treatment and extraction solvent, respectively. Critical parameters affecting UAE were optimized by experimental design. In the present research, the extraction technique used in the official EPA microwave-assisted extraction (MAE) methodology (United States Environmental Protection Agency) and UAE optimized methodology were compared. The results indicated that the developed method showed better efficacy since microwave extraction gave very poor responses for nicosulfuron and prosulfuron. The temperature extraction was also optimized; room temperature wasthe most suitable to work with. Under the optimized conditions, the proposed UAE-LC-MS/MS method was assessed in terms of linearity (R2 ≥ 0.9912), accuracy (recoveries around 100%), and precision (relative standard deviation, RSD < 13%). The absence of significant matrix effects allowed quantification in real samples by external calibration with standards prepared in water:methanol. Method sustainability was also evaluated using the metric tool AGREEPrep. Finally, the analysis of real contaminated samples revealed the presence of 7 out of the 9 studied herbicides with S-metolachlor at high concentrations in all samples.

Impact of soil residual auxin herbicide on seedling emergence and biomass differs between soil types, water pulse event, and seedling species

Synthetic‐auxin herbicides are often used to control woody plants and aid in grassland restoration. Seed‐based restoration is common alongside herbicide applications and there may be unintended effects of these herbicides on dryland plants at the seed and seedling stages. Additionally, abiotic conditions at the time of herbicide application may influence herbicide–soil–plant interactions. We conducted a greenhouse study to examine the effects of a common shrub‐control herbicide mix and its interaction with soil type and a post‐herbicide water pulse on common desert plant seeds and seedlings. In this greenhouse study, we found that a subset of species responded negatively to soil residual herbicide activity of a mixture of aminopyralid, clopyralid, and triclopyr at the seed and seedling stages. Species sensitive to soil herbicide residues were primarily shrub and forb species that are often the target species of herbicide applications for woody plant control, such as honey mesquite (Prosopis glandulosa) and creosote bush (Larrea tridentata). However, two shrub species (four‐wing saltbush [Atriplex canescens], soaptree yucca [Yucca elata]) and one perennial grass species (Arizona cottontop [Digitaria californica]), which are used in dryland restoration projects, were found to be particularly sensitive to soil residual herbicide activity. Thus, if using these herbicides to control woody plants and restore herbaceous vegetation via active seeding or relying on the in situ seed bank, considerations should be given to what species are used in the seed mix, what species are already present in the soil seed bank, and other details of the circumstances of herbicide application.

Effectiveness of graminicide application in chickpea crops in the Eastern Forest-Steppe of Ukraine

Goal. To determine the effect of herbicides, in particular graminicides with different active ingredients, on the weediness of crops and the yield of chickpea seeds in the conditions of the Eastern Forest-Steppe of Ukraine.&#x0D; Methods. Field, measuring and weighing, statistical.&#x0D; Results. Under conditions of the Eastern Forest-Steppe of Ukraine, 27 species of weed plants were found in chickpea crops (annual cereals — 3 species, annual dicots — 17 species, perennial dicotyledonous — 7 species). Annual cereal weeds dominated in number (76.4%), and annual dicot weeds (44.3%) in terms of raw mass. The highest technical efficiency against annual cereal weeds, when applied during the budding stage of chickpea, was provided by the graminicide Lemur, EC (hyzalofop-P-tefuryl, 40 g/ l) — 1.5 l/ ha (by the number and raw mass of cereals, 99.2 and 98.3%, respectively), and the lowest efficiency was provided by the graminicide Selenite, EC (clethodim, 120 g/ l) — 1.0 l/ ha (79.4 and 71.8%, respectively). Tank mixture of soil herbicides Panda, EC (pendimethalin, 330 g/ l) — 3.5 l/ ha + Steals, EC (flurochloridone, 250 g/ l) — 2.0 l/ ha, which was applied in the pre-emergence period, controlled only the number of annual dicot weeds (technical efficiency was 62.1—79.0%), which was associated with a number of factors (the presence of resistant weed species in the crops, different soil moisture during the application period by years, the use of the minimum recommended doses of herbicides). The studied herbicides did not affect perennial dicot weeds. Combining soil herbicides with graminicides reduced the total number of weeds by 73.2—87.9%, and their raw weight by 22.4—43.0%. The highest economic efficiency (0.28 t/ ha) was provided by the composition of the preparations Panda, EC — 3.5 l/ ha + Steals, EC — 2.0 l/ ha (tank mixture) + Queen Star Max, EC (hyzalofop-P-ethyl, 125 g/ l) — 0.8 l/ ha.&#x0D; Conclusions. In the absence of the effect of the studied herbicides on perennial dicot weeds and the insufficient effect of soil herbicides on annual dicot species, despite the high effectiveness of graminicides against cereals, it was not possible to obtain significant increase in the yield of chickpea seeds (from 0.13 to 0.28 t/ ha).

Investigation of the Transport and Sorption Behaviors of Atrazine and Metribuzine herbicides in Agricultural Soils of the Gölcük Plain

Pestisitler zararlı organizmaları engellemek, kontrol altına almak, ya da zararlarını bertaraf etmek için kullanılan tarım ilaçlarıdır. Dünyada 3 milyon tona, ülkemizde 30 bin tona ulaşan pestisit tüketimi ürün verimliliği açısından yararlı olsa da aşırı dozda ve bilinçsiz kullanımı neticesinde gıdalarda, toprak, su ve havada insan ve hayvan sağlığı için tehlike arz etmektedir. Dünyada kullanılan tarım ilaçlarının dağılımında herbisitler % 47 ile ilk sırada yer alırken, bunu % 29 ile insektisitler izlemekte, fungisitlerin ise % 19’luk bir payı bulunmaktadır. Atrazin ve metribüzin en çok kullanılan triazin herbisit türlerinden olup yabancı otlara karşı mücadele ederek ürün verimliliğini artırmayı amaçlamaktadır. Bu herbisitler, ulusal ve uluslararası kullanım sonucunda içme sularında ve su ortamında kirlilik açısından sorun teşkil etmektedir. Çevrede geniş alanda kullanımı ve dayanımından ötürü bu tür bileşiklerin taşınımı ve davranışı oldukça önemli olup özellikle Kocaeli civarında literatürde yapılmış herhangi bir çalışma bulunmamaktadır. Yapılacak çalışmanın amacı, atrazin ve metribüzin herbisitlerinin Gölcük Ovası civarındaki farklı türdeki tarım topraklarında tutunma ve taşınma davranışlarının incelenmesidir. Bu çalışma kapsamında bir seri kolon deneyleri gerçekleştirilmiştir. Atrazin ve metribüzin herbisitlerinin fiziksel ortama olan tutunma-geri bırakma davranışının bu tür kirleticilerle kirlenmiş toprakların risk değerlendirmesi için önemli etkileri olup, bu toprakların düzenlenmesinde, yönetilmesinde ve ıslahında oldukça önem arz etmektedir.

Sorption, leaching, and degradation of dicamba in two Brazilian soils: A study into soil layers

Understanding the behavior in soil of soluble and mobile herbicides, such as dicamba, is essential for efficient weed management. Thus, the objective of the research was to understand the sorption, leaching and degradation processes of dicamba along the profile of two Brazilian soils (Oxisol and Ultisol). The Oxisol collected is a very deep soil, the A horizon was collected in a layer of 0.10 m deep, the B horizon 2.0 m and the C horizon ranging from 5.0 to 6.0 m. In contrast, the Ultisol presents a difference between the most superficial horizons, the A horizon was collected at a depth of 0.10 m, the B horizon at around 1.0 m depth and the C horizon at a depth of 2.0–3.0 m. A High-Performance Liquid Chromatography (HPLC) was used to determine the herbicide in the soil solution. The Freundlich sorption coefficient (Kf) values of dicamba ranged from 0.53 to 0.88 mg (1-1/n) L1/n kg−1 in Oxisol and 0.25–0.69 mg (1-1/n) L1/n kg−1 in Ultisol, indicating a low sorption capacity of the herbicide in all profiles. The dicamba mobility index was higher in the Ultisol, ranging from 4.22 to 65.8 compared to the Oxisol, which ranged from 0.46 to 8.10. The degradation half-life time (DT50) of dicamba was short (∼4 days) in the A horizon of both soils compared to the other horizons. Moreover, persistence in the B and C horizons was higher in Oxisol (182 and > 250 days) compared to Ultisol (85.6 and 52.1 days, respectively). The sorption and mobility index of dicamba showed a correlation with soil pH and DT50 values, depending on the organic matter (OM) content. The recommendation of use of dicamba should consider the physical and chemical attributes of the soil as an alternative to reduce the risk of environmental contamination.

Enhancing butachlor degradation in soil by bioaugmentation of butachlor-degrading bacteria and mung bean cultivation

Butachlor has been extensively used to control weeds globally. In this study, the degradation performances of butachlor in soil by attenuation, augmentation with Pseudomonas sp. But1 and Pseudomonas sp. But, and mung bean (Vigna radiata L.) cultivation were determined. The results showed that the overall degradation rates in soil over 30 days were as follows: sterilized soil &lt; non-sterilized soil &lt; mung bean cultivation &lt; bioaugmentation. The dissipation of the herbicide in non-sterilized soil was observed to be 58.3 ± 5.5%, while butachlor was completely removed from soil with both bioaugmentation and mung bean cultivation after 30 days. Moreover, mung bean cultivation stimulated rhizospheric bacteria growth and enhanced the degradation. These results showed that both bioaugmentation and mung bean cultivation significantly increased the butachlor degradation in soil.

Adsorption Behavior and Residue Degradation of Triazine Herbicides in Soil Amended with Rice Straw Biochar

The removal of or decrease in pesticide residues in soil has attracted considerable attention, due to the serious pollution of pesticides in soil. The purpose of the study was to explore the adsorption behavior of biochar on pesticides and the impact on the degradation of pesticide residues in soil, providing a basis for the remediation of soil by biochar. Biochars were prepared via pyrolysis of rice straw at a high temperature (300 °C, 400 °C, 500 °C, 600 °C). The individual and competitive adsorption of three triazine herbicides, prometryn, atrazine, and simazine, on biochar was investigated, and the degradation of the herbicide residues in biochar-added soil was determined. The selected herbicides presented similar adsorption characteristics to rice straw biochar, and the amount of herbicides adsorbed increased with higher preparation temperature and the amount of biochar. The rice straw biochar adsorbed the studied herbicides simultaneously, and the adsorption amount decreased as follows: simazine &gt; atrazine &gt; prometryn. The competition adsorption of the selected herbicides on the biochar presented a lower adsorption affinity than that when they are adsorbed individually. The adsorption isotherm was best fitted by the Freundlich model. The half-lives of prometryn, atrazine, and simazine were 9.8~12.6 d, 5.2~8.1 d, and 3.7~5.6 d, respectively. Biochar addition increased the degradation of the evaluated herbicides in soil. The rice straw biochar could be the potential sorbents that can be implemented for the removal of pesticides.

Planting into a living cover crop alters preemergence herbicide dynamics and can reduce soybean yield

AbstractCereal rye cover crop (cereal rye) and preemergence (PRE) herbicides are becoming common practices for managing herbicide-resistant weeds in soybean production. Adopting these two practices in combination raises concerns regarding herbicide fate in soil, given that the cereal rye biomass can intercept the herbicide spray solution, preventing it from reaching the soil. Delaying cereal rye termination until soybean planting (planting green) optimizes biomass accumulation but might also increase PRE interception. To better understand the dynamics between cereal rye and PRE herbicides, a field experiment was conducted to evaluate two soil management practices (tillage and no-till) and two cereal rye termination practices in the planting-green system (glyphosate [1,260 g ae ha−1] and roller-crimper) on the spray deposition and fate of PRE herbicides and soybean yield. The spray deposition was assessed by placing water-sensitive paper cards on the soil surface before spraying the PRE herbicides (sulfentrazone [153 g ai ha−1] + S-metolachlor [1,379 g ai ha−1]). Herbicide concentration in soil (0 to 7.6 cm) was quantified 25 d after treatment (DAT). The presence of no-till stubble and cereal rye biomass reduced the spray coverage compared to tillage at PRE application, which reflected in a reduction in the concentration of both herbicides in soil 25 DAT. Soybean yield was reduced in all three years when the cereal rye was terminated with a roller-crimper but only reduced in one year when terminated with glyphosate. Our findings indicate that mainly cereal rye biomass reduced the concentration of PRE herbicides in the soil due to the interception of the spray solution during application. Although higher cereal rye biomass accumulation can provide better weed suppression according to the literature, farmers should be aware that the biomass can lower the concentration of PRE herbicides reaching the soil, thus intensifying field scouting to ensure that weed control is not being negatively affected.

Influence of herbicides on numbers and development Lumbricus terrestris

Unrestricted use of herbicides to control weeds in agriculture causes a decrease in sensitive individual populations of soil biota, among which Lumbricus terrestris should be noted. Because they make up a fairly significant part of the living biomass of the soil and play an important role in the functioning of the soil. The use of continuous-acting soil herbicides can cause not only 100% lethality, but also affect the functioning, growth, reproduction and habit of individuals of Lumbricus terrestris. The article has presented the results of field experiments and laboratory studies of the effect of soil herbicides of different chemical classes on the number and development of Lumbricus terrestris. The research results have established a negative effect on the development and number of individuals of the earthworm (Lumbricus terrestris) in the soil of the sunflower agrocenosis due to the use of herbicides. The number of earthworm individuals was reduced by 2.1 times when applying triazine herbicides (Gezagard) and 3.7 times when applying chloracetomids (Dual Gold, Harness) on the 30th day compared to the control. In addition, laboratory studies have proven that the use of soil herbicides in the recommended application rates activates the synthesis of glutathione-S-transferase in earthworms, and its content increases by 5.6–8.9% already after a day of contact with Harness and Dual Gold (1 min D), while in contact with the herbicide Gezagard the growth was 4.1% only on the 7th day of the experiment. Inhibition of earthworm acetylcholinesterase synthesis in contact with Harness and Dual Gold occurred on average by 43.0% already after 24 h and by 23.4% with Gezagard.

Soil herbicides in sunflower crops in the Eastern Forest-Steppe of Ukraine

Goal. To determine the influence of soil herbicides with different active substances on crop weediness and sunflower seed yield in the conditions of the Eastern Forest Steppe of Ukraine.&#x0D; Methods. Field, measuring and weighting, and statistical.&#x0D; Results. In 2019, with 13 mm of precipitation in the first period after applying soil herbicides, the effectiveness of herbicides in reducing the number and raw mass of weeds in sunflower crops was 60% and 45%, respectively, and in 2021 with 81 mm of precipitation, it was 89% and 95%. In 2021, there was phytotoxic suppression of culture plants by Kharnes, e.c. (acetochlor, 900 g/l), 2.5 l/ha. Despite this, Kharnes was the most effective in controlling the total number of weeds (91% and 96% for the first and second counts, respectively) and their raw mass (95%). Other preparations provided the following indicators: Proponit 720, EC (propisochlor, 720 g/l), 3.0 l/ ha (by quantity — 84% and 90%, by weight — 84%); Selefit, SC (promethrin, 500 g/l), 4.0 l/ha (by quantity — 79% and 81%, by weight — 70%); Prymekstra TZ Hold 500 SC (S-metolachlor, 312.5 g/l + terbuthylazine, 187.5 g/l), 4.5 l/ha (by quantity — 68% and 73%, by weight — 66%); Stomp 330, e.c. (pendimethalin, 330 g/l), 5.0 l/ha (by quantity — 51% and 63%, by weight — 60%); Komandyr, EC (clomazon, 480 g/l), 0.15 l/ha (26% and 52% by quantity, 37% by weight). Ambrosia artemisiifolia L. was resistant to the above soil herbicides. It was established that sunflower is a powerful competitor in agrophytocenosis. Its share in the total raw mass of agrophytocenosis, depending on the period of accounting, was from 65.8 to 82.0%, and in dry mass — from 61.8 to 80.2%. In addition, it was established that losses of the sunflower crop from weeds coincide with the specific share of weeds in the total mass of the agrophytocenosis. Soil herbicides provided the following increases in the yield of sunflower seeds (t/ha): Kharnes — 0.53; Proponit 720 — 0.46; Stomp 330 — 0.44; Prymekstra TZ Hold 500 SC and Selefit — 0.39; Komandyr — 0.17. It was found that sunflower was the most tolerant to Stomp 330, and the least — to Komandyr.&#x0D; Conclusions. In terms of the level of weed death in sunflower crops and the increase in the yield of its seeds, Kharnes was the best among soil herbicides, and Komandyr was the worst.

Development of a MOF-based SPE method combined with GC-MS for simultaneous determination of alachlor, acetochlor and pretilachlor in field soil.

In this work, a rapid, highly selective, reusable and effective method was developed for simultaneous determination of alachlor, acetochlor and pretilachlor in field soil by GC-MS coupled with MIL-101 based SPE. Main factors affecting the SPE by using MIL-101 were optimized. Moreover, by comparing with the other commercial materials such as C18, PSA and Florisil, the MIL-101(Cr) exhibited excellent adsorption performance, which aimed at amide herbicides. On the other hand, method validation displayed excellent method performance, achieving good linearities with r2 ≥ 0.9921, limits of detection between 0.25-0.45μgkg-1, enrichment factors ≥ 89, matrix effect in the range of ± 20%, recoveries between 86.3% and 102.4%, and RSD lower than 4.38%. The developed method was successfully applied to the determination of amide herbicides in soil taken from the wheat, corn and soybean field at different depths, where the concentration of alachlor, acetochlor and pretilachlor were in the range of 0.62-8.04μgkg-1. It was demonstrated that the more depth of soil, the lower of three amide herbicides. This finding could be proposed a novel method to detect the amide herbicides in the agriculture and food industry.

The straw presence preceding soybean crop increases the persistence of residual herbicides

Background There is little information on how different soil cover systems influence the residual effect of pre-emergent herbicides used in soybean cultivation in Brazil. Objective The objective was to compare the persistence of different pre-emergent herbicides in a Latosolic Dystrophic Red Nitosol soil in the presence or absence of black oat straw on the soil surface. Methods The herbicides used were chlorimuron-ethyl (40.0 g ai ha-1), diclosulam (70.1 g ai ha-1), flumioxazin (100.0 ai g ha-1) and saflufenacil (70.0 [...]

Research Progress on the Remediation Technology of Herbicide Contamination in Agricultural Soils

Asthe most-used pesticides in the agricultural production process, herbicides are mainly applied to protect crops from weeds. However, with the increased global demand for food, the dosage of herbicides is rising annually, and the efficacy of herbicides is getting stronger, which can cause some environmental issues including the accumulation, migration and transformation, and toxic effects of herbicides in agricultural soils. According to the characteristics of herbicide contamination and regional agricultural production, developing green and low-carbon technologies to reduce the ecological risks of herbicides to the soil-crop systems is a current concern in the ecological environment field. In this paper, relevant studies in recent years on herbicide pollution management in agricultural soils were identified and reviewed, the research progress and application cases of remediation technologies for herbicide pollution was analyzed and demonstrated, and future research and development tendency regarding the remediation of herbicides pollution was also prospected. Current remediation technologies for herbicides mainly include bioremediation technologies (e.g., microbial remediation, enzyme remediation, and phytoremediation), adsorption, and immobilization technologies (e.g., biochar-based materials). The bioremediation technologieswere rather mature and had been applied to the herbicide-contaminated soil in fields. Additionally, many successful bioremediation cases have been reported. Moreover, in order to enhance the remediation effect on herbicide pollution in agriculture soils, remediation technologies have been gradually developed from a single model to a coupled model with physical,chemical, and biological technology, which can maximize the synergy of the multi-technology application.