Herbicidal Properties Research Articles

Traditional uses, phytochemistry and biological activities of <i>Cotula cinerea</i> Del: A review

Cotula cinerea Del. belongs to the family Asteraceae. It is widely used in the traditional medicinal system for the treatment of various ailments such as colic, cough, diarrhea, digestive disorders, rheumatism, urinary and pulmonary infections, fever and headaches. Cotula cinerea contains a wide range of phytochemical compounds such as saponins, essential oils, tannins, flavonoids, steroids, and terpenoids. This paper reviews information pertaining its traditional uses, phytochemistry and biological activities such as antibacterial, antifungal, antioxidant, herbicidal, anti-diarrheal and analgesic properties. It is hoped that the information presented here might stimulate further studies that will possibly lead to development of therapeutic agents from this plant. Keywords: Asteraceae, Cotula cinerea , Traditional uses, Phytochemistry, Biological activities

Effects of 2,4-Di-tert-butylphenol and selected herbicides which induced lipid peroxidation on quantum yield and membrane integrity of weedy plants under dark and light conditions

2,4-Di-tert-butylphenol (2,4-DTBP) has herbicidal properties that cause lipid peroxidation on plant tissues. The present study aimed at examining the phytotoxic effects of 2,4-DTBP compared to that of selected herbicides which induced lipid peroxidation based on quantum yield (Φ) and membrane integrity of two bioassay weed species namely Oldenlandia verticillata and Leptochloa chinensis under light and dark conditions. Laboratory assays showed reduced Φ of 2,4-DTBP- and dinoterb-treated leaf discs within the first 3 h of the dark incubation period, with further decrease during the subsequent 15 h dark period and 6 h light period. Diuron drastically reduced the Φ of the bioassay species throughout the incubation period. The Φ of glufosinate-treated O. verticillata leaf discs was marginally reduced and decreased further upon light exposure; it had no effect on the Φ of L. chinensis. Fluridone, isoxaflutole, clomazone and oxyfluorfen also had negligible effect on Φ, whereas paraquat caused a rapid reduction in Φ upon light exposure for both bioassay species. 2,4-DTBP, paraquat and dinoterb induced electrolyte leakage during the dark incubation period; this was further increased in the presence of light for O. verticillata and L. chinensis. For both bioassay species, glufosinate caused a marked amount of electrolyte leakage, whereas diuron, fluridone, isoxaflutole, clomazone and oxyfluorfen had negligible effect on ion leakage. These results suggested that 2,4-DTBP has herbicidal activity comparable to that of dinoterb without dependence on light.

Toxicity of formulants and heavy metals in glyphosate-based herbicides and other pesticides.

The major pesticides of the world are glyphosate-based herbicides (GBH), and their toxicity is highly debated. To understand their mode of action, the comparative herbicidal and toxicological effects of glyphosate (G) alone and 14 of its formulations were studied in this work, as a model for pesticides. GBH are mixtures of water, with commonly 36-48% G claimed as the active principle. As with other pesticides, 10-20% of GBH consist of chemical formulants. We previously identified these by mass spectrometry and found them to be mainly families of petroleum-based oxidized molecules, such as POEA, and other contaminants. We exposed plants and human cells to the components of formulations, both mixed and separately, and measured toxicity and human cellular endocrine disruption below the direct toxicity experimentally measured threshold. G was only slightly toxic on plants at the recommended dilutions in agriculture, in contrast with the general belief. In the short term, the strong herbicidal and toxic properties of its formulations were exerted by the POEA formulant family alone. The toxic effects and endocrine disrupting properties of the formulations were mostly due to the formulants and not to G. In this work, we also identified by mass spectrometry the heavy metals arsenic, chromium, cobalt, lead and nickel, which are known to be toxic and endocrine disruptors, as contaminants in 22 pesticides, including 11 G-based ones. This could also explain some of the adverse effects of the pesticides. In in vivo chronic regulatory experiments that are used to establish the acceptable daily intakes of pesticides, G or other declared active ingredients in pesticides are assessed alone, without the formulants. Considering these new data, this assessment method appears insufficient to ensure safety. These results, taken together, shed a new light on the toxicity of these major herbicides and of pesticides in general.

Production of Phytotoxic Metabolites with Bioherbicidal Activities from Lasiodiplodia pseudotheobromae Produced on Different Agricultural Wastes Using Solid-State Fermentation

This study was carried out to optimize and enhance the production of phytotoxic metabolites from Lasiodiplodia pseudotheobromae (C1136) for its herbicidal properties using solid-state fermentation with various agricultural wastes available in Nigeria. The results obtained showed that banana peel (10.12 ± 0.10 g/100 g) and wheat bran (9.89 ± 0.11 g/100 g) had the highest protein content. Banana peel was observed to have the highest value of phosphorus (0.30 ± 0.05 g/100 g), closely followed by wheat bran (0.23 ± 0.06 g/100 g). Higher values of arginine contents were obtained for rice bran (3.06 ± 0.06 g/100 g), groundnut wastes (2.98 ± 0.08 g/100 g) and wheat bran (2.38 ± 0.08 g/100 g). These values are significant (p < 0.05). Endoamylase (64 U/g), exoamylase (50 U/g), isoamylase (43 U/g), protease (15 U/g), xylanase (12 U/g), cellulose (4.8 U/g) enzymes that were obtained from groundnut waste showed the best activities when compared to other substrates. It was observed that as the concentration of the extract increases so also are the radicle length, shoot length and germination rate on the tested seeds. Leaf necrosis assay showed that the phytotoxic metabolite from strain C1136 produced the largest necrotic area (3.2 ± 0.2 mm) on Amaranthus hybridus leaves when grown on groundnut waste. In comparison, the necrotic area of (2.5 ± 0.2 mm) was observed for Echinochloa crus-galli leave from phytotoxic metabolites grown on pineapple waste. The efficacy of the phytotoxic metabolites produced from strain C1136 in this study potends a strong solution for the environmental and human health challenges alludes to chemical herbicides.

Fifty Years of (Benz)oxaphospholene Chemistry.

The first synthesis of benzoxaphospholenes dates back to the 1960s. Since then, the structural variety of reported (benz)oxaphospholenes has steadily increased. Organophosphorus compounds have caught the interest of synthetic chemists for a couple of decades now because of their interesting biological properties. Oxaphospholenes, in particular, could serve as carbohydrate mimetics, and benzoxaphospholenes have been reported to possess bactericidal, insecticidal, herbicidal, and fungistatical properties. Transesterification reactions and addition of phosphorus nucleophiles to carbonyl compounds were reaction types that led to the production of the first (benz)oxaphospholenes. When it was discovered that allenylphosphonates could easily be obtained from propargyl alcohols and dialkyl halophosphites, the electrophile-induced cyclization reaction of these allenylphosphonate precursors resulted in a huge boom in the amount of reports on oxaphospholene synthesis. To this day, this method is still frequently used. Ring-closing metathesis and Horner-Wadsworth-Emmons reactions have also proven their potential for the preparation of oxaphospholenes. In recent years, Pd, Rh and Au-catalysis have made their entry, generating (benz)oxaphospholenes from a wide variety of simple substrates. A couple of miscellaneous methods are summarized at the end of the Review.

Herbicidal and fungistatic properties of fluorine analogs of phenoxyacetic herbicides

Aryloxy fluoroacetic acids 3a-3h – fluorine analogs of phenoxyacetic herbicides 2,4-D, MCPA, 2,4,5-T, and 4-CPA were efficiently synthesized in 29–88% yield, using appropriate phenols and either bromodifluoro- or bromofluoroacetic acid in the presence of sodium hydride as a base and in either dioxane or THF as solvents. Fluorine derivatives of 2,4-D (3a, 3b) show herbicidal activity against three weed species. Parent herbicides 2,4-D, MCPA, 2,4,5-T, 4-CPA, monofluorine derivatives of MCPA (3d) and 2,4,5-T (3f) show fungistatic activity against phytopatogenic fungi species Phytophtora cactorum.

Dual Fumigant and Herbicide Use Optimizes Replanting Preparation in a Virus- and Nematode-Affected Vineyard

Summary Goal: An exploratory study evaluated best-management techniques for replanting a commercial vineyard suffering from both a high incidence of Grapevine leafroll associated virus-3 and high densities of northern root-knot nematode ( Meloidogyne hapla ). The grower had two goals: to reduce the density of plant-parasitic nematodes, which can delay establishment of young vines, using a pre-plant fumigant, and to reduce survival of virus-infected vine tissue by applying an herbicide to the foliage prior to vine removal. Key Findings: Fall-applied metam sodium reduced densities of M. hapla in the following growing season. Its herbicidal properties also resulted in high root mortality. In cases where vines survived, only a few shoots (and suckers) emerged, displaying typical morphology. Fall-applied foliar glyphosate significantly reduced shoot and sucker regrowth, but did not kill root tissue. In the few instances where shoots and suckers grew the following spring, that tissue expressed typical symptoms of glyphosate phytotoxicity. While low rates of abnormal growth would eliminate much of the aerial reservoir of virus, the presence of live roots indicates that rogue vines and living root debris could contribute to infection of new, virus-free planting stock. Combining fumigant and foliar glyphosate was additive: nematode control, root mortality, and a lack of healthy shoot/crown sucker regrowth. Impact and Significance: This preliminary work showed that the combination of fall fumigation and foliar glyphosate application reduced nematode populations and vine survival. In situations where plant-parasitic nematodes are the sole issue facing replanting, fumigation alone suffices. Where virus alone is the impetus for replanting, fall-applied foliar glyphosate may provide sufficient overall vine mortality, with a caveat of low root mortality and its attendant risk of root-feeding vectors spreading the virus to new planting stock.

ACCERBATIN, a small molecule at the intersection of auxin and reactive oxygen species homeostasis with herbicidal properties.

The volatile two-carbon hormone ethylene acts in concert with an array of signals to affect etiolated seedling development. From a chemical screen, we isolated a quinoline carboxamide designated ACCERBATIN (AEX) that exacerbates the 1-aminocyclopropane-1-carboxylic acid-induced triple response, typical for ethylene-treated seedlings in darkness. Phenotypic analyses revealed distinct AEX effects including inhibition of root hair development and shortening of the root meristem. Mutant analysis and reporter studies further suggested that AEX most probably acts in parallel to ethylene signaling. We demonstrated that AEX functions at the intersection of auxin metabolism and reactive oxygen species (ROS) homeostasis. AEX inhibited auxin efflux in BY-2 cells and promoted indole-3-acetic acid (IAA) oxidation in the shoot apical meristem and cotyledons of etiolated seedlings. Gene expression studies and superoxide/hydrogen peroxide staining further revealed that the disrupted auxin homeostasis was accompanied by oxidative stress. Interestingly, in light conditions, AEX exhibited properties reminiscent of the quinoline carboxylate-type auxin-like herbicides. We propose that AEX interferes with auxin transport from its major biosynthesis sites, either as a direct consequence of poor basipetal transport from the shoot meristematic region, or indirectly, through excessive IAA oxidation and ROS accumulation. Further investigation of AEX can provide new insights into the mechanisms connecting auxin and ROS homeostasis in plant development and provide useful tools to study auxin-type herbicides.

Breaking apple dormancy using thidiazuron and air temperature effect on herbicide efficiency for ryegrass control

Thidiazuron can be used to promote sprouting induction in apples, found DE MARTIN et al. (2017). Authors concluded that the application of thidiazuron on ‘Daiane’ apples with a concentration of 125 and 250 mg L-1, added to mineral oil (3.5%), is a viable alternative to break gem dormancy with no negative impact on fruit production. The use of chemicals to break gem dormancy in apples is important if winter temperatures are not sufficiently low for dormancy overlapping (FRANCESCATTO 2014). The most common chemical used is hydrogen cyanamide, but it can be toxic for humans, especially for the applicators (HAWERROTH et al. 2010). Thus, this study reveals a less toxic alternative to break gem dormancy in ‘Daiane’ apples, guaranteeing similar production to the most commonly used chemical. The air temperature at the moment of herbicide spraying affects the efficiency of the chemical control of Italian ryegrass, found PEREIRA et al. (2017). Authors concluded that many grass killers are more efficient if application occurs at 20-22 oC. In addition, applications under temperatures of 30-34 oC are negatively affected, reducing the chemical control of ryegrass; moreover, the response can also be different among biotypes. Herbicide effect depends on many factors, including plant physiology, environmental conditions, application conditions etc., and those factors also influence each other (CARVALHO 2013). Air temperature (an environmental condition) can affect, for example, both plant physiology and herbicide properties. As herbicide absorption (also translocation and metabolism) is fundamental to herbicide action in plants, any factor affecting the movement of a plant killer into plant cells influences the chemical toxic action. Thus, the interaction among those factors is difficult to measure, so that any information on isolated effects is fundamental to establish efficient weed control programs.

2,4-Di-tert-butylphenol-induced leaf physiological and ultrastructural changes in chloroplasts of weedy plants

2,4-Di-tert-butylphenol (2,4-DTBP), a natural compound from plants, causes severe chlorosis and necrosis on Hedyotis verticillata and Leptochloa chinensis leaf blades by inducing oxidative stress through the generation of reactive oxygen species, leading to lipid peroxidation and membrane damage in leaf and root tissues. However, its effects on the physiology of photosynthesis through ultrastructural alterations in chloroplasts remain unclear. Therefore, this study examined the phytotoxic effects of 2,4-DTBP on chloroplast ultrastructure and leaf physiology of H. verticillata and L. chinensis in a 3-day assay. The results revealed that treating H. verticillata and L. chinensis seedlings with 2,4-DTBP significantly decreased shoot fresh weight on day 3 after treatment. 2,4-DTBP increased electrolyte leakage in H. verticillata, but no notable electrolyte leakage was detected in L. chinensis. Ultrastructural damage to chloroplasts was evident in both species, with a disorganised thylakoid system and undulating membranes, coupled with the absence of starch grains and an increased number of plastoglobuli. Damage to the chloroplast ultrastructure subsequently reduced the leaf greenness, quantum yield and stomatal conductance values. These results suggest that 2,4-DTBP has potent herbicidal properties that can alter chloroplast ultrastructure, thereby reducing physiological activity of these weedy plants.

Natural herbicide activity of Satureja hortensis L. essential oil nanoemulsion on the seed germination and morphophysiological features of two important weed species

The aim of the present study was to obtain an oil/water (O/W) nanoemulsion (NE) containing garden savory (Satureja hortensis) essential oil (EO) and evaluating its herbicidal activity against Amaranthus retroflexus and Chenopodium album. Gas chromatography (GC) and gas chromatography-mass spectrometry (GC-MS) were employed to determine the chemical composition of the EO. Carvacrol (55.6%) and γ-terpinene (31.9%) were the major EO components. Low energy method was applied, allowing achievement of EO nanodroplets. The NE also presented low polydispersity, and the mean droplet was below 130nm even after storage for 30d. Laboratory tests showed that the NE at different concentrations (100, 200, 400, 800, and 1000μL.L−1) significantly (P≤0.05) reduced the germination indices and the seedling's growth in dose-response. The inhibitory effect was the greatest at 800μL.L−1 NE. Overall, root length was more inhibited as compared to shoot length. Post-emergence application of NE at different concentrations (1000, 2000, 3000, 4000 and 5000μL.L−1 of EO) on 2–4 true leaves' stage of the weeds caused significant (P≤0.05) decrease in the growth factors in dose-dependent manner. Complete lethality was observed by 4000μL.L−1 NE sprayed on the weeds. Spraying of NE significantly (P≤0.05) reduced chlorophyll content in the tested weeds. Increasing in relative electrolyte leakage (REL) 1 and 5d after treatment represented significant cell membrane disruption and increased cell membrane permeability. Transmission electron microscope (TEM) pictures confirmed NE droplet size and demonstrated membrane destruction. The study approved that the NE of S. hortensis EO has herbicidal properties as it has high phytotoxic effect, and interferes with the germination, growth and physiological processes of the weeds. The production of NE from S. hortensis EO is a low energy method that offers a promising practical natural herbicide for weed control in organic agricultural systems.

Effect of Fatty Acid Methyl Esters on the Herbicidal Effect of Essential Oils on Corn and Weeds

In this study, we tested whether the addition of fatty acid methyl esters (FAME) of edible oils would influence the herbicidal effect of the essential oils (EO) of fiber hemp and peppermint (Mentha×piperitaL.) against common lambsquarters, barnyardgrass, and corn. The herbicidal properties of a 2.5% concentration of each EO in water mixtures with FAME were evaluated as sprays in a pot experiment. The oil-FAME mixtures showed phytotoxic effects against common lambsquarters and barnyardgrass expressed by a reduction in plant length and aboveground and root biomass, as measured three weeks after foliar spraying. Corn was the most tolerant species to the tested mixtures. Sunflower FAME alone was safe on corn but reduced the growth of weeds. Peppermint EO alone was the most phytotoxic on all tested species. In conclusion, the mixture of peppermint EO with oilseed rape FAME was the best treatment; however, improvement onCh. albumwould be desirable for commercial-level control.

Effect of Quaternary Ammonium Salts with Fluorine Atoms on Selected Weed Species

This study investigated the effects of four structurally different quaternary ammonium salts (QASs), i.e., tetrabutylammonium tetrafluoroborate [TBA][BF4], tetrahexylammonium tetrafluoroborate [THA][BF4], tetrabutylammonium hexafluorophosphate [TBA][PF6], and tetrahexylammonium hexafluorophosphate [THA][PF6], on the growth and development of three weed species: gallant soldier (Galinsoga parviflora Cav.), white goosefoot (Chenopodium album L.) and common sorrel (Rumex acetosa L.). The examined compounds were applied in the form of foliar spraying and soil application. Strong herbicidal properties of the examined compounds were demonstrated in case of their soil application. Growth inhibition of plant shoots and roots was greater with soil application than with foliar treatment. The strongest herbicidal activity of compounds was demonstrated with [TBA][BF4] have demonstrated [TBA][BF4] and [TBA][PF6] applied to the soil, while [THA][BF4] demonstrated the weakest herbicidal action. The increased concentration of applied QASs caused a decrease in the assimilation pigments, change in dry weight content and inhibition of length of shoots and roots.

Molecular imprinted polymer and its applications in Agriculture Science: a review

Contamination of environment due to indiscriminate use of herbicides poses severe risks to soil, water and air as well as human health. Therefore, need of easy, rapid and of low cost detection methods triggered the researcher to find out new technology. Molecularly imprinted polymers (MIPs), the synthetic materials are very useful in these circumstances. It offers several advantages to the environmental scientist, chemist, pharmaceutical, and agro food industry for analysis, sensoring, extraction, or preconcentration of analytes. The high toxicity of herbicides and their large use in modern agriculture practices has increased public concerns. In this review paper, imprinting and detection of herbicide, the recognition and transport properties of molecularly imprinted polymer (MIP) membranes prepared for herbicides such as Isoproturon and 2,4-D in particular have been discussed.

Removal of herbicidal ionic liquids by electrochemical advanced oxidation processes combined with biological treatment

ABSTRACTRecently a new group of ionic liquids (ILs) with herbicidal properties has been proposed for use in agriculture. Owing to the design of specific physicochemical properties, this group, referred to as herbicidal ionic liquids (HILs), allows for reducing herbicide field doses. Several ILs comprising phenoxy herbicides as anions and quaternary ammonium cations have been synthesized and tested under greenhouse and field conditions. However, since they are to be introduced into the environment, appropriate treatment technologies should be developed in order to ensure their proper removal and avoid possible contamination. In this study, didecyldimethylammonium (4-chloro-2-methylphenoxy) acetate was selected as a model HIL to evaluate the efficiency of a hybrid treatment method. Electrochemical oxidation or electro-Fenton was considered as a pretreatment step, whereas biodegradation was selected as the secondary treatment method. Both processes were carried out in current mode, at 10 mA with carbon felt as working electrode. The efficiency of degradation, oxidation and mineralization was evaluated after 6 h. Both processes decreased the total organic carbon and chemical oxygen demand (COD) values and increased the biochemical oxygen demand (BOD5) on the COD ratio to a value close to 0.4, showing that the electrolyzed solutions can be considered as ‘readily biodegradable.’

Persistence of herbicides in soil

While it is desirable for the chemicals to control weeds during the season of application, it is not desirable for them to persist and affect subsequent crop growth. Factors that determine the length of time herbicides persist fall into three categories: soil factors, climatic conditions, and herbicidal properties. Factors from each category strongly interact with one another. Earn 1 CEU in Integrated Pest Management by reading this article and taking the quiz at www.certifiedcropadviser.org/certifications/self‐study/796.

Optimizing production and evaluating biosynthesis in situ of a herbicidal compound, mevalocidin, from Coniolariella sp.

Mevalocidin is a fungal secondary metabolite produced by Coniolariella sp. It is a unique phytotoxin that demonstrates broad spectrum post-emergent herbicidal properties. With limited options for weed control, the commercialization of a natural product pesticide would be beneficial to organic farming. In this study, two mevalocidin-producing fungal strains, coded MSX56446 and MSX92917, were explored under a variety of growth conditions, including time, temperature, and media. The concentration of mevalocidin was quantitatively measured via LC-MS to determine the optimal setting for each condition. Maximum production was achieved for each condition at 20days, at 30°C, with YESD+agar, and with a media containing 2.5% dextrose. Furthermore, an advanced surface sampling technique was incorporated to gain a better understanding of the fungal culture's natural ability to biosynthesize and distribute this herbicide into its environment. It was shown that both fungi actively exude mevalocidin into their environment via liquid droplet formations known as guttates.

Antifungal Activity of Eucalyptus Oil against Rice Blast Fungi and the Possible Mechanism of Gene Expression Pattern.

Eucalyptus oil possesses a wide spectrum of biological activity, including anti-microbial, fungicidal, herbicidal, acaricidal and nematicidal properties. We studied anti-fungal activities of the leaf oil extracted from Eucalyptus. grandis × E. urophylla. Eleven plant pathogenic fungi were tested based on the mycelium growth rates with negative control. The results showed that Eucalyptus oil has broad-spectrum inhibitory effects toward these fungi. Remarkable morphological and structural alterations of hypha have been observed for Magnaporthe grisea after the treatment. The mRNA genome array of M. grisea was used to detect genes that were differentially expressed in the test strains treated by the Eucalyptus oil than the normal strains. The results showed 1919 genes were significantly affected, among which 1109 were down-regulated and 810 were up-regulated (p < 0.05, absolute fold change >2). According to gene ontology annotation analysis, these differentially expressed genes may cause abnormal structures and physiological function disorders, which may reduce the fungus growth. These results show the oil has potential for use in the biological control of plant disease as a green biopesticide.

Effect of sugarcane cropping systems on herbicide losses in surface runoff

Herbicide runoff from cropping fields has been identified as a threat to the Great Barrier Reef ecosystem. A field investigation was carried out to monitor the changes in runoff water quality resulting from four different sugarcane cropping systems that included different herbicides and contrasting tillage and trash management practices. These include (i) Conventional – Tillage (beds and inter-rows) with residual herbicides used; (ii) Improved – only the beds were tilled (zonal) with reduced residual herbicides used; (iii) Aspirational – minimum tillage (one pass of a single tine ripper before planting) with trash mulch, no residual herbicides and a legume intercrop after cane establishment; and (iv) New Farming System (NFS) – minimum tillage as in Aspirational practice with a grain legume rotation and a combination of residual and knockdown herbicides.Results suggest soil and trash management had a larger effect on the herbicide losses in runoff than the physico-chemical properties of herbicides. Improved practices with 30% lower atrazine application rates than used in conventional systems produced reduced runoff volumes by 40% and atrazine loss by 62%. There were a 2-fold variation in atrazine and >10-fold variation in metribuzin loads in runoff water between reduced tillage systems differing in soil disturbance and surface residue cover from the previous rotation crops, despite the same herbicide application rates. The elevated risk of offsite losses from herbicides was illustrated by the high concentrations of diuron (14μgL−1) recorded in runoff that occurred >2.5months after herbicide application in a 1st ratoon crop. A cropping system employing less persistent non-selective herbicides and an inter-row soybean mulch resulted in no residual herbicide contamination in runoff water, but recorded 12.3% lower yield compared to Conventional practice. These findings reveal a trade-off between achieving good water quality with minimal herbicide contamination and maintaining farm profitability with good weed control.

Physicochemical and herbicidal properties of emulsions of essential oils against Avena fatua L. and Chenopodium album L.

Essential oils have herbicidal effects, which can potentially be improved by the addition of adjuvants. The present study evaluated (1) the stability and other physicochemical properties of peppermint and caraway oils in oil-in-water emulsions and mixtures with commercially available adjuvants and (2) the phytotoxic effects of the foliar application of peppermint and caraway oil emulsions and mixtures to Chenopodium album L. (common lamb’s quarters) and Avena fatua L. (wild oat). An investigation was conducted with two multifunctional adjuvants, two nonionic surfactants, and two mixture constituents, i.e., organic acetic acid (vinegar) and citric acid, to assess the physicochemical properties of emulsions and mixtures with essential oils. In addition, two series of greenhouse pot experiments were set up to evaluate the herbicidal effects of these emulsions and mixtures against two common weed species. None of the emulsions or mixtures under study exhibited satisfactory stability. The emulsions of both essential oils had a significant herbicidal effect against C. album. None of the adjuvants significantly improved the efficacy. On the other hand, the herbicidal effect of emulsions against A. fatua depended on the ambient temperature in the greenhouse with treatments more effective at higher temperatures. The multifunctional adjuvants AS 500 and Atpolan Bio enhanced the herbicidal effect of caraway oil against A. fatua over 2 weeks. Peppermint oil alone induced considerable short-term herbicidal effects. Some adjuvants improved the efficacy of peppermint oil shortly after application, but due to regrowth no significant effects on biomass were obtained at harvest. In summary, the addition of adjuvants can improve the herbicidal effects of caraway and peppermint oil; however, further research into these effects is warranted.