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Self-assembled nanotechnology is a promising strategy for improving the effective utilization of pesticides due to its distinct advantages. Herein, an amide-bonded prodrug conjugate based on pyrimethanil (PYR) and butyric acid (BA) was successfully synthesized by the nucleophilic substitution reaction and subsequently self-assembled into spherical nanoparticles (PB NPs) with an average size of 85 nm through the solvent exchange method without using any toxic adjuvant. The results showed that PB NPs based on PYR and BA had a synergistic antimicrobial activity against

Nanocarrier-based pesticide formulations have been severely restricted in agriculture practices due to their high-cost preparation process, poor loading capacity, and toxicity issues. To overcome these issues, carrier-free small molecular self-assembled submicron particles (SMPs) with an improved photoactivated antimicrobial activity based on two natural microbicides berberine hydrochloride (BBR) and curcumin (CM) are constructed by noncovalent interactions through a simple and fast preparation process (solvent exchange method) without using any adjuvant. The results show that the optimized molar ratio of BBR to CM is 2:1 at pH 5 and 25 °C in an aqueous solution for the formation of B-C SMPs. The obtained B-C SMPs exhibit excellent physicochemical properties, such as uniform morphology (407 nm), low polydispersity index (0.283), and strong ζ-potential (+24.4 mV). The antibacterial activities of B-C SMPs against

Encapsulation of active ingredients into intelligent response controlled release carriers has been recognized as a promising approach to enhance the utilization efficiency and reduce the environmental risks of pesticides. In this work, an intelligent redox and pectinase dual stimuli-responsive pesticide delivery system was constructed by bonding pectin with metal-organic frameworks (FeMOF nanoparticles) which were loaded with pyraclostrobin (PYR@FeMOF-pectin nanoparticles). The successful fabrication of PYR@FeMOF-pectin nanoparticles was proved by a series of physicochemical characterizations. The results indicated that the loading capacity of PYR@FeMOF-pectin nanoparticles for pyraclostrobin was approximately 20.6%. The pectin covered on the surface of PYR@FeMOF nanoparticles could protect pyraclostrobin from photolysis and improve their spreadability on rice blades effectively. Different biological stimuli associated with Magnaporthe oryzae could trigger the release of pyraclostrobin from the pesticide-loaded core-shell nanoparticles, resulting in the death of pathogens. The bioactivity survey determined that PYR@FeMOF-pectin nanoparticles had a superior fungicidal activity and a longer duration against Magnaporthe oryzae than pyraclostrobin suspension concentrate. In addition, the FeMOF-pectin nanocarriers showed no obvious phytotoxicity and could enhance the shoot length and root length of rice plants. More importantly, PYR@FeMOF-pectin nanoparticles had an 8-fold reduction in acute toxicity to zebrafish than that of pyraclostrobin suspension concentrate. Therefore, the dual-responsive FeMOF-pectin nanocarriers have great potential for realizing site-specific pesticide delivery and promoting plant growth.

The abuse of toxic organic solvents and surfactants has caused immeasurable damage to human health and the environment. Therefore, based on the concept of green chemistry, developing a new type of nano-based pesticide formulation that does not contain harmful additives is urgent for sustainable pest management. Herein, we report two natural small molecular substances, spinosad (SSD) and sulfamic acid (SA), that were self-assembled into SSD-SA nanoparticles (SSD-SA NPs) through noncovalent interactions without involving any organic solvents or carriers. The results showed that the optimized mass ratio of SA to SSD was 1 : 4 at pH 5 and 35 °C in aqueous solution for the formation of SSD-SA NPs. The core–shell structured nanospheres with particle sizes of around 7 nm had excellent physical and chemical properties, such as strong positive charges (+47.8 mV) and good surface activity. SSD-SA NPs exhibited good quick-acting performance against Plutella xylostella larvae and Frankliniella occidentalis, and the insecticidal activities of SSD-SA NPs were significantly higher than that of the commercial SSD suspension. The genotoxicity evaluation showed that the genotoxicity of SSD to Vicia faba was reduced by a combination of self-assembly technologies and thus SSD-SA NPs posed a low risk to plant cells. These small molecular self-assembled SSD-SA NPs developed by a simple and green preparation process would have great potential for application in sustainable pest management.

The utilization of nanotechnology for the design of pesticide formulations has enormous potential to enhance the efficiency of pesticides and reduce their adverse impacts on the environment. However, the complicated fabrication process of nanosized carriers and their multi-step chemical modifications greatly restrict the practical applications of nanocarrier-based formulations. To address these issues, herein, self-assembled nanoparticles (NPs) based on fungicide fenhexamid (FHA) and polyhexamethylene biguanide (PHMB) were constructed by the electrostatic and hydrophobic interactions between FHA and PHMB in water solution without using carriers or adjuvants. The optimal temperature and mass ratio between FHA and PHMB for the formation of NPs were 60 °C and 10 : 7, respectively. Obtained spherical NPs with sizes of 50–250 nm were stable in neutral and acidic aqueous mediums and displayed desirable physicochemical properties (strong surface positive charges, low conductivity, high light stability, and good surface activity). Moreover, the combination of FHA and PHMB by the self-assembly of NPs had a synergistic effect on the antimicrobial activity, and NPs exhibited higher activities against Pseudomonas syringae pv. lachrymans, Botrytis cinerea, and Sclerotinia sclerotiorum than FHA and PHMB. Furthermore, the results of the genotoxicity evaluation in Vicia faba showed that the prepared NPs did not further increase the cytotoxicity of FHA. Overall, the formation of co-self-assembly nanoparticles of FHA and PHMB via a simple and green approach may be a novel avenue for sustainable plant disease management and provides inspiration to construct new nano-based pesticide formulations.

Volatilization and leaching are two critical pathways for pesticide transportation from their applied areas to non-target regions. Nanocarrier-based formulations can improve the use efficiency and reduce the off-target effects of pesticides, however, the complicated preparation process seriously restricts the large-scale application of nanopesticides in the agricultural field. In this work, taking 2-(2,4-dichlorophenoxy) acetic acid (2,4-D), 2-methyl-4-chlorophenoxyacetic acid (MCPA), and 3,5-dibromo-4-hydroxybenzonitrile (bromoxynil) as model herbicides, herbicide-intercalated Zn–Al hydrotalcites (herbicide@HTlcs) were facilely fabricated by a modified co-precipitation method without heating, aging, organic solvents, and inert gas. The obtained herbicide@HTlcs showed high entrapment efficiencies (71.7%–86.7%), a sheet structure with an average size of 339.4 nm, and positive surface charges (+40.5). The volatilities of herbicide@HTlcs were reduced more than 3-fold compared with those of pure herbicides. The release rates of 2,4-D@HTlcs were in line with the selectivity sequence of HTlcs for the anions and controlled by non-Fickian diffusion. The leaching experiments performed in two agricultural topsoils collected from Beijing and Yunnan province and a grassland soil from Neimenggu province all demonstrated that the developed 2,4-D@HTlc nanosheets could evidently retard 2,4-D leaching through the soil. Additionally, 2,4-D@HTlcs exhibited no delay in the control efficacy against Amaranthus retroflexus compared with free 2,4-D sodium salt. This study provides a novel insight into the facile fabrication of controlled release formulations of pesticides that can reduce the volatilization and leaching risks simultaneously.

The side effects caused by some pesticides with high off-target movement have brought great risks to the environment and human health. Here, taking 2,4-dichlorophenoxyacetic acid (2,4-D) as a model herbicide to reduce its volatilization and leaching, a supramolecular self-assembly mediated by branched polyethylenimine (B-PEI) was constructed through noncovalent molecular recognition. The results showed that 2,4-D/B-PEI nanoparticles (NPs) with a mean particle size of 168 nm can be formed by electrostatic interaction, hydrophobic effect, and π-π stacking when the mass ratio of 2,4-D to B-PEI with the average molecular weight of 10 000 (B-PEI 10k) was 40:20, and their generation was not susceptible to common inorganic ions such as Ca

As one of plant growth regulators, mepiquat chloride (MC) has become one of the most useful tools to manage plant geometry during cotton growth and development. Since it is highly water-soluble and...

A microcapsule is an ideal choice to realize effective utilization of a pesticide and reduce environmental pollution. A novel preparation method of a microcapsule was developed by complex coacervat...

Stimulus-responsive release systems for site-specific pesticide delivery are one of the promising strategies to improve the use efficiency of pesticides as well as decrease environmental damage. He...

A controlled release formulation based on silica microcapsules is an ideal selection to improve both the effective utilization and duration of pesticides to decrease ecological damage. Herein, a simple and green method for preparing double-shelled microcapsules was developed using a newly prepared quaternary ammonium ionic liquid (IL) as the functional additive to entrap avermectin (Ave) in mesoporous silica nanospheres (MSNs) and tannic acid-Cu (TA-Cu) complex as the sealing agent to form the core-shell structure (Ave-IL@MSN@TA-Cu). The obtained microcapsules with an average size of 538 nm had pH-responsive release property and good stability in soil. The half-life of microcapsules (34.66 days) was 3 times that of Ave emulsifiable concentrate (EC) (11.55 days) in a test soil, which illustrated that microcapsules could protect Ave from rapid degradation by microorganisms by releasing TA, copper, and quaternary ammonium in the soil. Ave-IL@MSN@TA-Cu microcapsules had better nematicidal activity and antibacterial activity than Ave EC due to the synergistic effect of Ave, IL, and copper incorporated in the microcapsules. Pot experiments showed that the control efficacy of microcapsules was 87.10% against Meloidogyne incognita, which is better than that of Ave EC (41.94%) at the concentration of 1.0 mg/plant by the root-irrigation method after 60 days of treatment owing to the extended duration of Ave in microcapsules. The simple and green method for the preparation of double-shelled microcapsules based on natural quaternary ammonium IL would have tremendous potential for the extensive development of controlled release pesticide formulations.

Silver nanoparticles (AgNPs) have remarkable and broad-spectrum antibacterial activities against Gram-positive (G+) and Gram-negative bacteria (G-). However, the negative surface potential of AgNPs limits their antibacterial activities due to the electrostatic repulsion with the negatively charged bacterial cell membrane. To address the limitation, AgNPs were loaded in the mesoporous silica nanoparticles by preparing silver core-mesoporous silica shell nanocapsules (Ag@MSNs), and then, a cationic antibacterial polymer, quaternary ammonium polyethyleneimine (QPEI), was used to modify Ag@MSNs for improving their surface potential and antibacterial activities. The results showed that the obtained Ag@MSN-QPEI exhibited a high positive surface potential (+39.6 mV) and a strong electrostatic attraction with Pseudomonas syringae pv. lachrymans cells in coculture, resulting in an excellent bacterial cell-targeting effect. At the same concentration, Ag@MSN-QPEI exhibited less silver content (reducing the silver content of Ag@MSNs by 19%), higher antibacterial activities, and longer effective duration against Clavibacter michiganensis subsp. michiganensis (G+) and P. syringae pv. lachrymans (G-) than Ag@MSNs and QPEI alone. The excellent bacterial cell-targeting effect and synergistic antibacterial action combined with QPEI accounted for the significantly enhanced antibacterial activities of Ag@MSN-QPEI. Therefore, using a cationic antibacterial polymer to confer the bacterial cell-targeting effect and synergistic antibacterial action would be extended to other antimicrobial materials.

Photosensitizers need to be activated by external light to achieve phototherapy. However, unsatisfactory tissue penetration of light and uncontrollable light intensity limit their application. To o...

In this study, nine pyrimethanil ionic liquids (PILs) were synthesized through an acid-base reaction with nine naturally derived organic acid anions to improve the physicochemical properties and reduce the environmental adverse impacts. The PILs presented lower volatilization, higher photostability, better soil adsorption capacity, and improved fungicidal activity relative to pyrimethanil. When the length of the carbon chains in the anions was increased, the PILs showed better properties in terms of melting point, water solubility, volatility, and surface tension. The photostabilities and fungicidal activities of the PILs were significantly improved when cyclic compounds were used as the paired anion ions. With enhanced physicochemical properties and better fungicidal activity, PIL7 was selected as the best alternative to pyrimethanil. The intrinsic disadvantages of pyrimethanil could be surmounted using the system developed in the study; thus, ILs could have immense potential in the development of eco-friendly and efficient fungicides in the future.

Mesotrione is one of the triketone herbicides that are widely used in corn fields to control broadleaf and some grass weeds because of its high herbicidal activity and crop safety. However, mesotri...

Based on the specific binding between the receptors and ligands, novel targeted nanocapsules were prepared by using silica covalently bonded with dopamine to increase the insecticidal efficacy of λ-cyhalothrin. The targeted release mechanism of λ-cyhalothrin nanocapsules (NC) nanocapsules was verified by enzymatic analysis, fluorescent marking method and high performance liquid chromatograph. The results showed NC had uniform particle size (800 nm) and approximately 31% (w/w) loading efficiency of λ-cyhalothrin. The stability of λ-cyhalothrin in nanocapsuels was improved under different pH and temperature conditions. The NC showed sustainable release properties and the release kinetics mainly belonged to Fickian diffusion at all experimental conditions. Compared to λ-cyhalothrin emulsifiable concentrate and microcapsule suspension, the NC exhibited more excellent insecticidal activity. The micronucleus test indicated that NC significantly reduced the genotoxicity of λ-cyhalothrin to non-target organisms. This work offers a novel and efficient way to use targeted drug delivery system to improve the insecticidal activity, and may be extended to other pesticides in the future.

Triflumizole, a broad-spectrum systemic fungicide, has been widely used for the management of fungal diseases in plants. However, rapid photolysis and high risk to the aquatic environment limit its application. Ionic liquid (IL) forms of active pharmaceutical ingredients are innovative and promising agents that can optimize the application of the starting chemicals through the selection, or functionalization of the counterions (cation or anion). In this study, triflumizole was paired with various natural organic acids to develop novel ILs for improving the physicochemical properties and reducing the toxicity to fish. The results showed that the obtained ILs had low surface tension and lipophilicity and could protect triflumizole against degradation under UV irradiation as well as exhibit more excellent biological activity against Botrytis cinerea than triflumizole. The IL forms of triflumizole reduced the dosage and frequency of this fungicide, accordingly minimized the negative effect on environment. The IL contained salicylic acid as anion decreased > 4-fold toxicity to adult zebrafish over TFM. The results reported here create new application possibilities for imidazole fungicides and offer some heuristic rules for the design of active pharmaceutical ingredients-ionic liquids.

Controlled release formulations can reduce the losses of pesticides and prolong their effective duration. In this work, a novel pH responsive pesticide delivery system based on kasugamycin-conjugated ZnO quantum dots (KAS-ZnO QDs) was established via a cleavable benzoic–imine covalent bond. The as-prepared KAS-ZnO QDs could protect KAS against photodegradation effectively due to the UV shielding effect of KAS-ZnO QDs. The KAS and Zn2+ released from KAS-ZnO QDs in the acid condition could achieve a synergistic antimicrobial activity. The greenhouse experiment confirmed that application of KAS-ZnO QDs had a longer duration and a better antimicrobial activity against bacterial fruit blotch compared to KAS and NH2-ZnO QDs treatments, and showed no any toxicity to plants. Thus, pH-responsive KAS-ZnO QDs could achieve a synergistic antimicrobial effect and offer a new approach to manage plant diseases.

Based on excellent optical properties and microbicide activity, porphyrinic metal-organic frameworks (MOFs) are widely used as drug release carriers for their photodynamic therapy (PDT). In this work, porous porphyrinic MOFs (PCN-224) nanoparticles were synthesized for loading and controlling release of tebuconazole by using meso-tetra(4-carboxyphenyl)porphine (H2TCPP) as organic linker, metal ions clusters Zr (IV) as nodes, and subsequently assembled layer by layer of pectin and chitosan to obtain tebuconazole microcapsules (Tebuc@PCN@P@C). The results showed that the prepared MOFs had loading efficiency of tebuconazole about 30% (w/w), and the obtained stimuli-responsive microcapsules showed adjustable controlled-release characteristics with pectinase in acidity environment. Tebuc@PCN@P@C microcapsules displayed excellent double activities of PDT and microbicide against Xanthomonas campestris pv. campestris, Pseudomonas syringae pv. Tomato and Alternaria alternate. Safety evaluation on Chinese cabbage indicated they almost had no any damage to plants. Thus, stimuli-responsive dual-microbicidal MOFs microcapsules were demonstrated a great potential as an efficient delivery system in pesticide formulations.

Cyhalothrin is lethally toxic to aquatic organisms and has caused adverse effects in the hydrosphere. It is urgent to develop efficient and sustainable material for its removal. High-quality HKUST-1 was rapidly synthesized by cholinium ionic liquids (ILs) in water at room temperature. Yields of HKUST-1 showed obviously positive correlation with Hammett values of ILs. When applying CuCl2 as a copper salt, the yield of products was reached up to 95.5%, which was much higher than that of reported research. The reaction could be readily scalable with high space-time yield (242512 kg m−3 d−1). Additionally, ZrO2@HKUST-1 composite was successfully synthesized through a sol-gel method without complicated heat treatment. The whole process eliminates the use of environmentally unfriendly solvents/amines and enables the production of material at a reasonable cost. The obtained HKUST-1 and ZrO2@HKUST-1 possessed large pore volume (0.88–0.95 cm3 g−1) and high surface area (1152–1484 m2 g−1). The composite material was used for the adsorption/degradation of cyhalothrin and showed superior photocatalytic activity under moderate visible light, as compared to pure ZrO2, HKUST-1 and commercial TiO2 samples. ZrO2@HKUST-1 displayed the high cyhalothrin adsorption capacity of 333 mg g−1 through π−π stacking, which facilitated more target molecules to contact the composite in a short time. ZrO2 incorporating with HKUST-1 protected ZrO2 nanoparticles from rapid agglomeration, thus narrowed the band gap of the composite. Moreover, the formation of a junction between HKUST-1 and ZrO2 effectively reduced the recombination of photoinduced carriers in composite. Therefore, the novel ZrO2@HKUST-1 composite can be used as a sustainable efficient heterogeneous photocatalyst for the removal of organic pollutant.

Auxin herbicides have attracted continuously increasing attention because of their frequently application worldwide, slow degradation rates and potential toxicity to human beings. It is urgent to develop a fast and practical method to monitor them in environmental samples. Ionic liquids (ILs) are not intrinsically “green” and most of them are as toxic as other solvents. Therefore, tuning for maximizing advantageous properties of ILs and minimizing side effects are crucial steps. In this work, guanidinium IL was applied to preconcentrate and clean up ultra-trace auxin herbicides via designable binding sites. The structurally optimized IL had improved pretreatment performance and was significantly less cytotoxic than imidazolium IL toward human keratinocytes. For further improving the sensitivity of detection, we quantified the concentration of herbicides by a fast and mild fluorescence derivatization. Under optimized pretreatment conditions, high recoveries in real water samples (above 80%), short pretreatment time (

Nicosulfuron is widely used in agriculture because of its high selectivity, wide weeding spectrum, and excellent herbicide performance. However, it is necessary to add adjuvants to stabilize nicosulfuron so as to maximize its weed-control efficacy. In this study, five novel herbicidal ionic liquids (HIL1-5) based on nicosulfuron were synthesized through an acid–base reaction by pairing with tetrabutylammonium, benzyltriethylammonium, 2-hydroxyethyltrimethylammonium, hexadecyltrimethylammonium, and hexadecypyridinium, representing different types of cations with short-chain branched hydrocarbon, long-chain branched hydrocarbon, fused heterocycle, and aromatic hydrocarbon, respectively. The results showed that HILs had a low solubility and surface tension, and moderate octanol–water partition coefficient, which could reduce the risk of leaching and polluting the water environment to some extent. Nicosulfuron-based herbicidal ionic liquids were more stable than the nicosulfuron under high temperature and ultraviolet radiation, and the stability of the herbicidal ionic liquids followed the order of HIL5 > HIL1 > HIL3 > HIL2 > HIL4. HIL5 without any adjuvants exhibited a better control efficacy against gramineous and broadleaf weeds than nicosulfuron. The results showed that the physicochemical property of herbicide could be optimized by selecting suitable paired ions to solve the problems existing in practical application of the herbicide and could reduce its negative impact on the environment.

Considering the severity of plant pathogen resistance toward commonly used agricultural microbicides, as well as the potential threats of agrichemicals to the eco-environment, there is a pressing need for antimicrobial approaches that are capable of inactivating pathogens efficiently without the risk of inducing resistances and harm. In this work, a porphyrin metal-organic framework (MOF) nanocomposite was constructed by incorporating 5,10,15,20-tetrakis(1-methyl-4-pyridinio)porphyrin tetra(p-toluenesulfonate) (TMPyP) as a photosensitizer (PS) in the cage of a variant MOF (HKUST-1) to efficiently produce singlet oxygen (1O2) to inactivate plant pathogens under light irradiation. The results showed that the prepared PS@MOF had a loading rate of PS about 12% (w/w) and excellent and broad-spectrum photodynamic antimicrobial activity in vitro against three plant pathogenic fungi and two pathogenic bacteria. Moreover, PS@MOF showed outstanding control efficacy against Sclerotinia sclerotiorum on cucumber in the pot experiment. Allium cepa chromosome aberration assays and safety evaluation on cucumber and Chinese cabbage indicated that PS@MOF had no genotoxicity and was safe to plants. Thus, porphyrin MOF demonstrated a great potential as an alternative and efficient new microbicide for sustainable plant disease management.

In this work, a pH-responsive pesticide delivery system using mesoporous silica nanoparticles (MSNs) as the porous carriers and coordination complexes of Cu ions and tannic acid (TA-Cu) as the capping agent was established for controlling pyraclostrobin (PYR) release. The results showed the loading capacity of PYR@MSNs-TA-Cu nanoparticles for pyraclostrobin was 15.7 ± 0.5% and the TA-Cu complexes deposited on the MSNs surface could protect pyraclostrobin against photodegradation effectively. The nanoparticles had excellent pH responsive release performance due to the decomposition of TA-Cu complexes under the acid condition, which showed 8.53 ± 0.37%, 82.38 ± 1.67% of the encapsulated pyraclostrobin were released at pH 7.4, pH 4.5 after 7 d respectively. The contact angle and adhesion work of PYR@MSNs-TA-Cu nanoparticles on rice foliage were 86.3° ± 2.7° and 75.8 ± 3.1 mJ/m2 after 360 s respectively, indicating that TA on the surface of the nanoparticles could improve deposition efficiency and adhesion ability on crop foliage. The control effect of PYR@MSNs-TA-Cu nanoparticles against Rhizoctonia solani with 400 mg/L of pyraclostrobin was 85.82% after 7 d, while that of the same concentration of pyraclostrobin EC was 53.05%. The PYR@MSNs-TA-Cu nanoparticles did not show any phytotoxicity to the growth of rice plants. Meanwhile, the acute toxicity of PYR@MSNs-TA-Cu nanoparticles to zebrafish was decreased more than 9-fold compared with that of pyraclostrobin EC. Thus, pH-responsive PYR@MSNs-TA-Cu nanoparticles have great potential for enhancing targeting and environmental safety of the active ingredient.

Allyl isothiocyanate (AITC) is a natural product used as a food additive. Due to its strong volatility and broad biological activity, AITC is considered as a bio-fumigant to control soil-borne fungal diseases in agriculture, creating an urgent need for evaluation of the antifungal activity of AITC. Here we study the effect of AITC on Fusarium solani growth and explore the molecular mechanisms. The results indicated that AITC causes rapid inhibition of F. solani after 5 min, hyphal deformity, and electrolyte leakage. A yeast-like vacuolar transient receptor potential channel regulator (FsYvc1, a STRPC family member) was identified in F. solani that seems to play a role in this fungi AITC sensitivity. Genetic evidence suggests the gene FsYvc1 is involved in F. solani growth, development, and pathogenicity. Loss of FsYvc1 resulted in hypersensitivity of F. solani to AITC and induced reactive oxygen species (ROS) accumulation ∼ 1.3 to 1.45- folds that of the wild type (WT), and no difference responses to CaCl2, NaCl, KCl, SDS, and Congo red when compared with WT. In addition, ΔFsYvc1-17 showed significantly reduced (∼ 1-fold) glutathione-S-transferase (GST) expression compared with the WT without AITC induction. Upon exposure to 4.8 μg/mL AITC for 3 h, the relative expression levels were ∼ 12-30 fold higher in both the WT and ΔFsYvc1-17. Nevertheless, no difference in GST expression level was observed between the WT and ΔFsYvc1-17. The current study provides novel insights into the toxicity mechanisms of AITC. Considering our results that show the key role of FsYvc1, we propose that it could act as a new molecular target for future fungicide development.

In this work, 12 novel herbicidal ionic liquids (HILs) based on acifluorfen were prepared by pairing with the fluorescent hydrazides or different alkyl chains for increasing activities and reducing negative impacts on the aquatic environment. The results showed that the fluorescence of coumarin hydrazide in the HILs was applied as the internal and supplementary light source to meet the requirement of light wavelength range of acifluorfen, which improved the phytotoxicity of acifluorfen to weeds by enhancing singlet oxygen generation with increased sunlight utilization. The herbicidal activities of HILs were related positively with the length of chain of cation under high light intensity and depended mainly on the fluorescence characteristic of the cation under low light intensity, and the double salt IL forms of acifluorfen containing coumarin hydrazide and n-hexadecyltrimethylammonium had enhanced efficacies against broadleaf weeds in the field. Compared with acifluorfen sodium, HILs had lower water solubility, better surface activity, weaker mobility in soils, and higher decomposition temperature. These results demonstrated that HILs containing different cations provided a wider scope for fine-tuning of the physicochemical and biological properties of herbicides and established a promising way for the development of environmentally friendly herbicidal formulations.

Nanotechnology-based pesticide formulations can improve the utilization rate of pesticides and reduce their negative effects on the environment. In this work, prochloraz was encapsulated within the...

In this study, a series of p-aromatic isothiocyanates are prepared by reacting p-aromatic amines with carbon disulphide and further treating with molecular iodine to yield corresponding isothiocyanate derivatives. The structures of newly synthesized compounds are confirmed by IR, NMR, and MS data. Activity of the products against plant pathogenic fungi and bacteria is tested and the structure-activity relationship is approached. p-Nitrophenyl isothiocyanate most efficiently inhibits Rhizoctonia solani and Erwinia carotovora. The order of seven aromatic isothiocyanates antifungicidal activity is following: p-nitrophenyl > p-methoxyphenyl > p-chlorophenyl > p-methylphenyl > p-ethylphenyl > phenyl > p-fluorophenyl. For antibacterial activity, the order was p-nitrophenyl > p-chlorophenyl > p-methylphenyl > p-ethylphenyl > p-fluorophenyl > phenyl > p-methoxyphenyl. The present study indicates that some of the compounds exhibit promising antimicrobial activity and can be used as an alternative to the traditional synthetic fungicides for controlling R. solani and E. carotovora.

As a widely used herbicide, picloram has been frequently detected in the aquatic environment due to its high leaching potential and low adsorption by soil. To reduce aquatic environmental risk of this herbicide caused by leaching and runoff, five herbicidal ionic liquids (HILs) based on picloram were prepared by pairing isopropylamine, octylamine, octadecylamine, 1-methylimidazole, 4-methylmorpholine respectively. Their physicochemical properties including water solubility, octanol-water partition coefficient, surface activity, leaching, as well as soil adsorption were compared. The results showed that these properties could be adjusted by appropriate selection of counter cations. The HILs with long alkyl chains in cations had low water solubility and leaching characteristics, good surface tension and lipophilicity, as well as high soil adsorption. Compared with currently used picloram in the forms of potassium salts, HIL3 had more excellent herbicidal activity against broadleaf weeds and may offer a lower use dosage. The HILs based on picloram can reduce its negative effects on the aquatic environment and can be used as a desirable alternative to commercial herbicidal formulations of picloram in future.

Five novel ionic liquids (ILs), 1,3-dibutylimidazolium bromide [BBMIm][Br], 1-pentyl-3-butylimidazolium bromide [BPMIm][Br], 1-hexyl-3-butylimidazolium bromide [BHMIm][Br], 1,1'-(butane-1,4-diyl)bis(3-butylimidazolium) bromide [C4(BMIm)2][Br2], and 1,1'-(butane-1,4-diyl)bis(3-methylimidazolium) bromide [C4(MIm)2][Br2], were prepared and used in situ to react with bis(trifluoromethane)sulfonamide lithium salt to extract the myclobutanil, tebuconazole, cyproconazole, and prothioconazole from water samples. The results showed that mono-cationic ILs had much better recovery than dicationic ILs, and mono-imidazolium IL bearing butyl groups at N-1 and N-3 sites had the best recovery. When the length of the alkyl substituent group was more than four carbons at N-3 site, the recovery decreased with increase of alkyl chain length of 1-butylimidazolium IL. The extraction efficiency order of triazoles from high to low was [BBMIm][Br], [BPMIm][Br], [BHMIm][Br], [BMIm][Br] (1-butyl-3-methylimidazolium bromide), [C4(BMIm)2]Br2, [C4(MIm)2]Br2. An in situ ionic liquid dispersive liquid-liquid microextraction combined with ultrasmall superparamagnetic Fe3O4 was established as a pretreatment method for enrichment of triazole fungicides in water samples by using the synthetic [BBMIm][Br] as the cationic IL and used to detect analytes followed by high-performance liquid chromatography. Under the optimized conditions, the proposed method showed a good linearity within a range of 5-250 μg L-1, with the determination coefficient (r2) varying from 0.998 to 0.999. High mean enrichment factors were achieved ranging from 187 to 323, and the recoveries of the target analytes from real water samples at spiking levels of 10.0, 20.0, and 50.0 μg L-1 were between 70.1% and 115.0%. The limits of detection for the analytes were 0.74-1.44 μg L-1, and the intra-day relative standard deviations varied from 5.23% to 8.65%. The proposed method can be further applied to analyze and monitor pesticides in other related samples. Graphical Abstract The scheme of the in-situ DLLME method for the determination of triazoles using the imidazolium-based ionic liquids.

Growing concerns about environmental pollution and future food supplies have encouraged the development of controlled release formulation of pesticides. Porous hollow silica (PHS) is an ideal carrier to prepare pesticide microcapsule due to its hollow structure, high surface area, and biocompatibility. However, the cumbersome preparation process of pesticide microcapsule based on PHS severely restricted its extensive development and application in pesticide products. Herein, an improved soft-template method for preparing pesticide loaded PHS was developed by using newly prepared tributylhexadecylphosphonium dicyanamide [P44416][N(CN)2] as the solvent and soft-template agent. The model pesticide prochloraz (PRO) was entrapped inside PHS in situ without loading process during the preparation process and a core–shell structure sphere (PRO@PIL-PHS-PEC microcapsule) was obtained by coating PRO@PIL-PHS with pectin in solution through electrostatic adsorption. The obtained PRO@PIL-PHS-PEC microcapsules had high drug encapsulation efficiency and good photostability with pectinase and pH responsive release properties. Plate antagonism tests and pot trials indicated that the PRO@PIL-PHS-PEC had a significant long-term control efficacy against S. sclerotiorum and no adverse impact on the growth of rapeseed plant. The prepared PRO@PIL-PHS-PEC could effectively reduce the use of pesticides by significantly improving the effective utilization rate and efficacy of pesticides. The simple and green method for synthesis of PRO@PIL-PHS-PEC based on PIL would have great potential for large-scale application of controlled release formulation in the field of pesticides.

Smart core–shell nanocarriers can release pesticides in response to stimuli from the microenvironment associated with pests and the physiological behaviors of protected crops. In this work, a smart nanocarrier (MIL-101(Fe)@silica) with dual functions of site-specific delivery and plant nutrition was fabricated to deliver chlorantraniliprole (CAP) for sustainable pest management. The results showed that the developed CAP@MIL-101(Fe)@silica with a size of approximately 270 nm had a stable core–shell nanostructure with a highly crystallized regular octahedron. The photostability of the drug loaded in the carrier under UV-light irradiation was 16.5 times higher than that of technical CAP. The introduction of the silica shell prevented the premature escape of CAP from the MIL-101(Fe) core in the environment and endowed the developed nanohybrid carrier with base-triggered release properties. In a laboratory bioassay, CAP@MIL-101(Fe)@silica had favorable insecticidal activity (LC50 = 0.389 mg/L) in controlling Plutella xylostella larvae. After fourteen days of spraying in the greenhouse experiment, the mortality of the CAP@MIL-101(Fe)@silica treatment (86%) against P. xylostella larvae was significantly higher than that of the CAP suspension concentration treatment (36.7%). In addition, MIL-101(Fe)@silica was safe for crops and could enhance the crop fresh weight and dry weight by 18.6–19.6% and 4.8–17.7%, respectively. Therefore, MIL-101(Fe)@silica could be used as a biocompatible carrier for site-specific pesticide delivery and simultaneously as a fertilizer for crop growth, which would be a novel route for the development of a precise pesticide delivery nanoplatform.

In this work, in-situ ionic liquid dispersive liquid-liquid microextraction combined ultrasmall Fe 3 O 4 magnetic nanoparticles was developed as a kind of pretreatment method to detect pyrethroid pesticides in water samples. New anion-exchange reagents including Na[DDTC] and Na[N(CN) 2 ] were optimized for in-situ extraction pyrethroids, which showed enhanced microextraction performance. Pyrethroids were enriched by hydrophilic ionic liquid [P 4448 ][Br] (aqueous solution, 200 μL, 0.2 mmol mL −1 ) reaction in-situ with anion-exchange reagent Na[N(CN) 2 ] (aqueous solution, 300 μL, 0.2 mmol mL −1 ) forming hydrophobic ionic liquid as extraction agent in water sample (10 mL). Ultrasmall superparamagnetic iron oxide nanoparticles (30 mg) were used to collect the mixture of ionic liquid and pyrethroids followed by elution with acetonitrile. The extraction of ionic liquid strategies was unique and efficiently fulfilled with high enrichment factors (176–213) and good recoveries (80.20–117.31%). The method was successively applied to the determination of pyrethroid pesticides in different kinds of water samples with the limits of detection ranged from 0.16 to 0.21 μg L −1 . The proposed method is actually nanometer-level microextraction (average size 80 nm) with the advantages of simplicity, rapidity, and sensitivity.

Microcapsules are highly desirable for attaining the most effective utilization of the pesticide as well as reducing environmental pollution. In this work, a novel urease-responsive system was prepared using isocyanate-functionalized silica cross-linked with polyethylenimine (silica–IPTS–PEI) via urea bonds. The results demonstrated that the silica–IPTS–PEI microcapsules had a high pendimethalin loading efficiency (approximately 30% w/w) and could effectively enhance the thermal and light stability of pendimethalin. The release curves agreed with the Ritger and Peppas equation, and the release of pendimethalin was diffusion-controlled. The release rates of synthesized silica-IPTS-PEI microcapsules showed positive correlation with the temperature. In weak acid and base conditions, the pendimethalin release rates were higher than under neutral conditions, and the silica–IPTS–PEI microcapsules displayed excellent urease-responsive property with controlled release performance. Compared with pendimethalin emul...

Many herbicides exhibit some disadvantages such as high water solubility and volatility after application, which lead to potential threats to the aquatic and atmospheric environment and human health. Herbicidal ionic liquids (HILs) can effectively eliminate these intrinsic shortcomings by pairing with appropriate counterions (cation or anion). In this study, new HILs based on bromoxynil with eight typical cations were synthesized to reduce the negative impacts of currently used forms of bromoxynil. All the obtained compounds were investigated for solubility, octanol–water partition coefficient, surface activity, volatilization rate, and herbicidal activity in a greenhouse. The results showed that the HILs with long alkyl chains in the cations had reduced water solubility and volatilization rate, better surface activity and Kow, and substantially improved efficacy against weeds over bromoxynil sodium. Due to their adjustable physicochemical properties and improved herbicidal activity, the HILs could tremendously reduce the adverse impacts of bromoxynil on the environment and human health and may be potential alternatives to currently popular forms of bromoxynil in the future.

The increasing frequency of using traditional copper-based bactericides has resulted in phytotoxicity to plants and heavy metal pollution to the environment. A novel formulation of copper bactericides with excellent environmental compatibility and high systemicity as well as safety and low toxicity is a preferred choice to improve excessive defects of traditional copper-based bactericides. Nanosilica Schiff-base copper(II) complexes (Silica-NMP-Cu) were prepared and evaluated in terms of their antimicrobial activity and toxicity. The results showed that, compared with Kocide, the Silica-NMP-Cu had excellent antimicrobial activity against four kinds of bacteria with reduced 54.31–64.75% amount of copper and could move upward and downward freely in the plant with the water transportation as well as increase disease resistance by increasing the concentration of salicylic acid in plants, which could reduce the frequency of using copper-based bactericide. Application of the cucumber safety assessment and Alliu...

It is highly desirable to construct stimuli-responsive nanocarriers for improving pesticides targeting and preventing the pesticides premature release. In this work, a novel redox and α-amylase dual stimuli-responsive pesticide delivery system was established by bonding functionalized starch with biodegradable disulfide-bond-bridged mesoporous silica nanoparticles which loaded with avermectin (avermectin@MSNs-ss-starch nanoparticles). The results demonstrated that the loading capacity of avermectin@MSNs-ss-starch nanoparticles for avermectin was approximately 9.3 %. The starch attached covalently on the mesoporous silica nanoparticles could protect avermectin from photodegradation and prevent premature release of active ingredient. Meanwhile, the coated starch and disulfide-bridged structure of nanoparticles could be decomposed and consequently release of the avermectin on demand when nanoparticles were metabolized by glutathione and α-amylase in insects. The bioactivity survey confirmed that avermectin@MSNs-ss-starch nanoparticles had a longer duration in controlling Plutella xylostella larvae compared to avermectin emulsifiable concentrate. In consideration of the superior insecticidal activity and free of toxic organic solvent, this target-specific pesticide release system has promising potential in pest management.