Delivery of acetamiprid to tea leaves enabled by porous silica nanoparticles: efficiency, distribution and metabolism of acetamiprid in tea plants

Flavor evolution of unsweetened green tea beverage during actual storage: Insights from multi-omics analysis

The flavor evolution of unsweetened green tea beverage (USGTB) under actual storage is critical for quality control yet remains unclear. Unlike previous studies conducted by accelerated shelf-life testing, this research investigated sensory-chemical changes in naturally stored USGTB (0-7 months) through multi-omics integrating metabolomics and sensomics. Results identified the 5-month as a critical point for flavor preservation. The EC-EGCG dimer emerged as a novel aging marker, contrasting with freshness indicators (ascorbic acid and other antioxidants). Protocatechuic acid and 2-furoic acid served as multi-flavor contributors (yellowish, sweetness and astringency), whereas L-tartaric acid and malic acid enhanced sourness. Concurrently, aroma deterioration was driven by the diminished (E)-β-ionone and accumulated methyl salicylate. Mechanistically, oxidations of ascorbic acid, catechins, and fresh aroma-related volatiles, flavonoid glycosylation, and oligosaccharides hydrolysis collectively drove color darkening, astringency enhancement, sweetness intensification, and cooked-off flavor development. These findings provided targeted quality control points for USGTB during actual shelf-life.

Thiacloprid-silica nano-delivery system enhances toxicity against Aphis gossypii and improves non-target biosafety

Nanotechnology aligns with the requirements of sustainable development of agriculture, and nano-pesticides offer a promising approach to controlling agricultural pests and increasing productivity. Non-target predators also play a crucial role in pest controls and enhancing the efficacy of pesticide on target organisms. Reducing the toxicity of pesticides to non-target organisms is key to of coordinating chemical control and biological control methods. Therefore, it is essential to assess the toxicity of nano-pesticides on non-target predators. In this study, a carbon dots-doped mesoporous silica nano-delivery system (Thi@CD-MSN) was successfully developed using CD-MSN as carrier material and thiacloprid (Thi) as a model pesticide. The results demonstrated that the synthesized Thi@CD-MSN exhibited a relatively high loading efficiency (33.58%). Laboratory bioassay experiments revealed that Thi@CD-MSN demonstrated effective insecticidal activity (LC50 = 21.67 mg/L) in controlling Aphis gossypii Glover. Besides, the acute toxicity of Thi@CD-MSN on Chrysoperla pallens larvae was significantly lower than that of Thi, as was its toxicity to 4T1 cells. These findings suggest that CD-MSN can serve as an ecological safety carrier for pesticide delivery, improving the effective utilization of Thi while reducing the risks to non-target predators. These results are essential for comprehending the effects of nano-pesticides on non-target predators, providing informative data for implementing biological and chemical control strategies. It strengthens the safety evaluation of nano-pesticides.

Unveiling the Contamination Patterns of Neonicotinoid Insecticides: Detection, Distribution, and Risk Assessment in Panax notoginseng across Plant Parts

This study analyzed neonicotinoid insecticides (NEOs) and metabolite (m-NEOs) residues in 136 Panax notoginseng samples via ultra-performance liquid chromatography-tandem mass spectrometry. Imidacloprid was the most detected NEO (88.24% of samples), ranging from 1.50 to 2850 μg/kg. To the best of our knowledge, some novel NEOs were detected in P. notoginseng for the first time. NEO clustering patterns varied among plant parts, with higher contamination in leaves and flowers. Fourteen NEO/m-NEOs, including cycloxaprid and acetamiprid, showed site-specific behavior, indicating the possibility of using multiple NEOs simultaneously during planting, resulting in formation of distinct metabolites in different plant parts. Transfer rates in decoction and infusion ranged from 10.06 to 32.33%, reducing residues postprocessing. Dietary risk assessment showed low hazard quotients (HQa: 7.05 × 10-7 to 2.09 × 10-2; HQc: 3.74 × 10-7 to 2.38 × 10-3), but risk-ranking scores indicated potential hazards with imidacloprid and acetamiprid in flowers and leaves. The findings are expected to promote safety assessment and distribution research of NEOs in plants.

Use of hydroponics-based evaluation for phenotyping tolerance/susceptibility to the aphid, Uroleucon compositae and inheritance analysis of aphid tolerance in a global germplasm collection of Carthamus tinctorius L. (Safflower)

Carthamus tinctorius L. (Safflower) is an important oilseed crop that is cultivated globally. Aphids are a serious pest of safflower and cause significant yield losses of up to 80% due to their ability to multiply rapidly by parthenogenesis. In this study, we report the identification of an aphid-tolerant accession in safflower following screening of a representative global germplasm collection of 327 accessions from 37 countries. Field-based screening methods gave inconsistent and ambiguous results for aphid tolerance between natural and controlled infestation assays and required ~ 3 months for completion. Therefore, we used a rapid, high-throughput hydroponics-based assay system that allows phenotyping of aphid tolerance/susceptibility in a large number of plants in a limited area, significantly reduces the time required to ~ 45 days and avoids inconsistencies observed in field-based studies. We identified one accession out of the 327 tested germplasm lines that demonstrated aphid tolerance in field-based natural and controlled infestation studies and also using the hydroponics approach. Inheritance analysis of the trait was conducted using the hydroponics approach on F1 and F2 progeny generated from a cross between the tolerant and susceptible lines. Aphid-tolerance was observed to be a dominant trait governed by a single locus/gene that can be mobilized after mapping into cultivated varieties of safflower. The hydroponics-based assay described in this study would be very useful for studying the molecular mechanism of aphid-tolerance in safflower and can also be used for bioassays in several other crops that are amenable to hydroponics-based growth.

Supplementary Information

The online version contains supplementary material available at 10.1007/s12298-024-01467-0.

Impacts of nano-acetamiprid pesticide on faba bean root metabolic response and soil health

The associated benefits and potential environmental risks of nanopesticides on plant and soil health, particularly in comparison with traditional pesticides, have not been systematically elucidated. Herein, we investigated the impacts of the as-synthesized nano-acetamiprid (Nano-Ace, 20 nm) at low (10 mg/L), medium (50 mg/L), high (100 mg/L) doses and the corresponding high commercial acetamiprid (Ace, 100 mg/L) on the physiological and metabolic response of faba bean (Vicia faba L.) plants, as well as on rhizosphere bacterial communities and functions over short-, medium- and long-term exposures. Overall, Nano-Ace exposure contributed to basic metabolic pathways (e.g., flavonoids, amino acids, TCA cycle intermediate, etc.) in faba bean roots across the whole exposure period. Moreover, Nano-Ace exposure enriched rhizosphere beneficial bacteria (e.g., Streptomyces (420.7%), Pseudomonas (33.8%), Flavobacterium (23.3%)) and suppressed pathogenic bacteria (e.g., Acidovorax (44.5%)). Additionally, Nano-Ace exposure showed a trend of low promotion and high inhibition of soil enzyme activities (e.g., invertase, urease, arylsulfatase, alkaline phosphatase) involved in soil C, N, S, and P cycling, while the inhibition was generally weaker than that of conventional Ace. Altogether, this study indicated that the redox-responsive nano-acetamiprid pesticide possessed high safety for host plants and soil health.

Development of a Safe and Effective Bacillus thuringiensis-Based Nanobiopesticide for Controlling Tea Pests

Mg(OH)2 was used as the nanocarrier of the Bacillus thuringiensis (Bt) Cry1Ac protein, and the synthesized Cry1Ac-Mg(OH)2 composites were regular and uniform nanosheets. Nano-Mg(OH)2 could effectively improve the insecticidal effect of the Cry1Ac protein toward Ectropis obliqua. It could enhance the damage degree of the Cry1Ac protein to intestinal epithelial cells and microvilli, induce and enrich the production of reactive oxygen species (ROS) in the midgut, and enhance the degradation of the Cry1Ac protein into active fragments. Furthermore, an anti-rinsing assay showed that the Cry1Ac-Mg(OH)2 composites were bound to the notch structure of the tea leaf surface. The retention of the Cry1Ac protein increased by 11.45%, and sprayed nano-Mg(OH)2 was rapidly absorbed by different tissues of tea plants. Moreover, nano-Mg(OH)2 and composites did not significantly affect non-target organisms. These results show that nano-Mg(OH)2 can serve as a safe and effective biopesticide carrier, which provides a new approach for stable and efficient Bt preparation.

Prospects and hazards of silica nanoparticles: Biological impacts and implicated mechanisms

With the thrive of nanotechnology, silica nanoparticles (SiNPs) have been extensively adopted in the agriculture, food, cosmetic, and even biomedical industries. Due to the mass production and use, SiNPs inevitably entered the environment, resulting in ecological toxicity and even posing a threat to human health. Although considerable investigations have been conducted to assess the toxicity of SiNPs, the correlation between SiNPs exposure and consequent health risks remains ambiguous. Since the biological impacts of SiNPs can differ from their design and application, the toxicity assessment for SiNPs may be extremely difficult. This review discussed the application of SiNPs in different fields, especially their biomedical use, and documented their potential release pathways into the environment. Meanwhile, the current process of assessing SiNPs-related toxicity on various model organisms and cell lines was also detailed, thus estimating the health threats posed by SiNPs exposure. Finally, the potential toxic mechanisms of SiNPs were also elaborated based on results obtained from both in vivo and in vitro trials. This review generally summarizes the biological effects of SiNPs, which will build up a comprehensive perspective of the application and toxicity of SiNPs.

A mesoporous silica nanocarrier pesticide delivery system for loading acetamiprid: Effectively manage aphids and reduce plant pesticide residue

A multifunctional nanomaterials-based agrochemical delivery system could supply a powerful tool for the efficient use of pesticides. Redox-responsive carriers as novel delivery systems of pesticide application in agriculture could promote the pest control and reduce plant pesticide residues due to the controllable release of agrochemicals. Herein, neonicotinoid insecticide acetamiprid (Ace) was encapsulated with decanethiol in a mesoporous silica nanocarrier pesticide delivery system for a nanopesticide Ace@MSN-SS-C10. The Ace@MSN-SS-C10 had redox-responsive sustained release behavior triggered by glutathione (GSH). Moreover, the Ace@MSN-SS-C10 possessed excellent wettability, adhesion performance, stability, and biosafety. Greenhouse experiments showed that foliar spraying 1.5 mg Ace@MSN-SS-C10 per plant reduced the populations of adult and juvenile aphids (Aphis craccivora Koch) on Vicia faba L. after 5 days of aphid infestation by 98.7 % and 99.3 %, respectively. Notably, the leaf final Ace residue (0.32 ± 0.004 mg/kg) of Ace@MSN-SS-C10 application at the dose of 1.5 mg/plant after 5 days of aphid infestation was lower than the international Codex Alimentarius Commission (CAC) maximum residue limits (0.4 mg·kg^-1) or much lower (24.87-folds decrease) than those treated with conventional Ace (40 % acetamiprid water dispersible granule). Altogether, this GSH-dependent redox-responsive delivery system for loading acetamiprid can develop as an efficient and environmentally-friendly nanopesticide to control aphids in sustainable agriculture.

Degradable Self-Destructive Redox-Responsive System Based on Mesoporous Organosilica Nano-Vehicles for Smart Delivery of Fungicide

The development of stimuli-responsive controlled release formulations is a potential method of improving pesticide utilization efficiency and alleviating current pesticide-related environmental pollution. In this study, a self-destruction redox-responsive pesticide delivery system using biodegradable disulfide-bond-bridged mesoporous organosilica (DMON) nanoparticles as the porous carriers and coordination complexes of gallic acid (GA) and Fe(III) ions as the capping agents were established for controlling prochloraz (PRO) release. The GA-Fe(III) complexes deposited onto the surface of DMON nanoparticles could effectively improve the light stability of prochloraz. Due to the decomposition of GA-Fe(III) complexes, the nano-vehicles had excellent redox-responsive performance under the reducing environments generated by the fungus. The spreadability of PRO@DMON-GA-Fe(III) nanoparticles on the rice leaves was increased due to the hydrogen bonds between GA and rice leaves. Compared with prochloraz emulsifiable concentrate, PRO@DMON-GA-Fe(III) nanoparticles showed better fungicidal activity against Magnaporthe oryzae with a longer duration under the same concentration of prochloraz. More importantly, DMON-GA-Fe(III) nanocarriers did not observe obvious toxicity to the growth of rice seedlings. Considering non-toxic organic solvents and excellent antifungal activity, redox-responsive pesticide controlled release systems with self-destruction properties have great application prospects in the field of plant disease management.

Environmentally Friendly Zr-Based MOF for Pesticide Delivery: Ultrahigh Loading Capacity, pH-Responsive Release, Improved Leaf Affinity, and Enhanced Antipest Activity

The stimuli responsive pesticide delivery system (PDS) has drawn increasing attention in recent years, a system which can effectively improve the utilization of pesticides. In the current research, we report a pH responsive PDS by using carboxymethyl cellulose (CMC) modified Zr-based metal organic frameworks (UiO-66-NH₂) as the nanocarrier for acetamiprid (ATP). UiO-66-NH₂-CMC possesses a large surface area and abundant pores, which can effectively load ATP, and the loading rate is as high as 90.79%. Compared with free ATP, the ATP@UiO-66-NH₂-CMC nanopesticide exhibits pH responsive controlled release behavior, and the pesticide can sustained release to the medium. In addition, it also shows improved leaf affinity, which makes it easier to wet the leaf surface and improve the utilization of pesticide. Therefore, ATP@UiO-66-NH₂-CMC displays better antipest activity against aphids than free ATP does. Meanwhile, ATP@UiO-66-NH₂-CMC shows no negative effects on the germination and growth of maize, showing good biosafety. Moreover, the ATP@UiO-66-NH₂-CMC nanopesticide does not contain any toxic organic solvents or additives. Therefore, we hope that it can be a suitable candidate for plant protection and sustainable agriculture.

Nanoencapsulation of Acetamiprid by Sodium Alginate and Polyethylene Glycol Enhanced Its Insecticidal Efficiency

Nanoformulation has been considered one of the newly applied methods in integrated pest management strategies. In this research, a conventional neonicotinoid insecticide acetamiprid was nanoencapsulated via AL (Sodium Alginate) and PEG (Polyethylene Glycol) and tested against the elm leaf beetle Xanthogaleruca luteola. The synthesized particles had spherical-like morphology and nanoscale based on TEM (Transmission Electron Microscopy) and DLS (Dynamic Light Scattering). The encapsulation efficiency and loading percentages of acetamiprid in AL and PEG were 92.58% and 90.15%, and 88.46% and 86.79%, respectively. Leaf discs treated with different formulations by the leaf-dipping method were used for oral toxicity assays. The LC₅₀ values (Lethal Concentration to kill 50% of insect population) of acetamiprid and Al- and PEG-nanoencapsulated formulations on third-instar larvae were 0.68, 0.04, and 0.08 ppm, respectively. Based on the highest relative potency, AL-encapsulated acetamiprid had the most toxicity. The content of energy reserve protein, glucose, and triglyceride and the activity of detoxifying enzymes esterase and glutathione S-transferase of the larvae treated by LC₅₀ values of nanoformulations were also decreased. According to the current findings, the nanoencapsulation of acetamiprid by Al and PEG can increase its insecticidal performance in terms of lethal and sublethal toxicity.

The Synergistic Effect of Thiamethoxam and Synapsin dsRNA Targets Neurotransmission to Induce Mortality in Aphis gossypii

Sublethal doses of insecticides have many impacts on pest control and agroecosystems. Insects that survive a sublethal dose of insecticide could adapt their physiological and behavioral functions and resist this environmental stress, which contributes to the challenge of pest management. In this study, the sublethal effects of thiamethoxam on gene expression were measured through RNA sequencing in the melon aphid Aphis gossypii. Genes regulating energy production were downregulated, while genes related to neural function were upregulated. To further address the function of genes related to neurotransmission, RNA interference (RNAi) was implemented by transdermal delivery of dsRNA targeting synapsin (syn), a gene regulating presynaptic vesicle clustering. The gene expression of synapsin was knocked down and the mortality of aphids was increased significantly over the duration of the assay. Co-delivery of syn-dsRNA and thiamethoxam reversed the upregulation of synapsin caused by low-dose thiamethoxam and resulted in lethality to melon aphids, suggesting that the decreased presynaptic function may contribute to this synergistic lethal effect. In addition, the nanocarrier star polycation, which could bind both dsRNA and thiamethoxam, greatly improved the efficacy of lethality. These results increase our knowledge of the gene regulation induced by sublethal exposure to neonicotinoids and indicated that synapsin could be a potential RNAi target for resistance management of the melon aphid.

Fabricating Network-Link Acetamiprid-Loading Micelles Based on Dopamine-Functionalized Alginate and Alkyl Polyglucoside To Enhance Folia Deposition and Retention

The development of an eco-friendly nanopesticide formulation can alleviate the problems of low pesticide utilization and environmental pollution. However, the development of green nanopesticide carriers with ideal physical properties and specific bioavailability is still a challenging task at present. In this study, we propose a novel binary additive pesticide carrier system that is a functional polysaccharide-based polymer/surfactant (Alg-DA/APG) to improve the deposition and retention of pesticide droplets. The self-assembled micelle morphology of Alg-DA/APG and its effect on the apparent viscosity were investigated by transmission electron microscopy (TEM) and a Discovery HR-2 rotational rheometer. Surface tension was carried out to investigate the surface activity and critical micelle concentration (CMC) of Alg-DA/APG. The drop impacting experiments exhibited superior antisplash performance of Alg-DA/APG. Furthermore, a binary additive was used as the carrier material and loaded acetamiprid to prepare nanopesticide formulation Ace@Alg-DA/APG. The encapsulation efficiency (EE) and acetamiprid release behavior from Ace@Alg-DA/APG were also studied. Moreover, the dynamic contact angle (DCA) and retention experiment showed that the DCA and wetting radius at 600 s were, respectively, 6.8 ± 2.39° and 4.044 ± 0.0662 mm for the Ace@0.05 wt % Alg-DA/0.05 wt % APG on the banana foliage surface, and its retention rates on foliage surface were up to 74.80% after washing. The novel binary additive as a nanopesticide carrier has the potential to alleviate the problems of low pesticide utilization and environmental pollution in the future.