In order to reduce the usage amount of pesticide fertilizers and protect the natural environment, seed coating agents are receiving increased wide concern. In this study, the active constituent (pesticide) and inactive components (surfactants and film former) of the seed coating agents were screened and optimized by the wet sand processing superfine grinding method. The fungal inhibition test of pesticides showed that thifluzamide, fludioxonil, pyraclostrobin, and difenoconazole have an obvious fungal inhibitory effect on wheat sharp eyespot, take-all, and root rot. LAE-9 and polyacrylamide + carboxymethyl cellulose (CMC) is recommended for the safe surfactant and film former, respectively, based on the seed germination test. Moreover, 6% difenoconazole · fludioxonil flowable concentrate for seed coating (FSC) stimulates the seedling growth of wheat, advances the growth of root, and improves biomass in the field trial, meanwhile, the control efficiency reached above 80%. Thus, we suggested it can be used as an effective seed coating agent for the control of soil-borne diseases in wheat. The seed coating agent has the characteristics of disease prevention, increasing crop yield, and safety of environment, which is of significance in practical application.

The transfer of pesticide residues from herbal teas to their infusion is a subject of particular interest. In this study, a multi-residue analytical method for the determination of pyrethroids (fenpropathrin, beta-cypermethrin, lambda-cyhalothrin, and fenvalerate) in honeysuckle, chrysanthemum, wolfberry, and licorice and their infusion samples was validated. The transfer of pyrethroid residues from tea to infusion was investigated at different water temperatures, tea/water ratios, and infusion intervals/times. The results show that low amounts (0–6.70%) of pyrethroids were transferred under the different tea brewing conditions examined, indicating that the infusion process reduced the pyrethroid content in the extracted liquid by over 90%. Similar results were obtained for the different tea varieties, and pesticides with high water solubility and low octanol–water partition coefficients (log K_ow) exhibited high transfer rates. Moreover, the estimated values of the exposure risk to the pyrethroids were in the range of 0.0022–0.33, indicating that the daily intake of the four pyrethroid residues from herbal tea can be regarded as safe. The present results can support the identification of suitable tea brewing conditions for significantly reducing the pesticide residue levels in the infusion.

A series of novel pyrazole amide derivatives 3a–3p which take TMV PC protein as the target has been designed and synthesized by the reactions of 5-chloro-1-aryl-3-methyl-1H-pyrazole-4-carboxylic acids with 5-amino-1-aryl-1H-pyrazole-4-carbonitriles. All the compounds were characterized by ¹H-NMR, mass spectroscopy and elemental analysis. Preliminary bioassays indicated that all the compounds acted against the tobacco mosaic virus (TMV) with different in vivo and in vitro modes at 500 μg/mL and were found to possess promising activity. Especially, compound 3p showed the most potent biological activity against tobacco mosaic virus (TMV) compared to ningnanmycin, and a molecular docking study was performed and the binding model revealed that the pyrazole amide moiety was tightly embedded in the binding sites of TMV PC (PDB code: 2OM3).

To clarify the residue formation of prothioconazole and its main metabolite in wheat plants, the uptake, translocation, and metabolism of prothioconazole in wheat roots and leaves were investigated by nutrient solution culture and the spraying method. The results showed that prothioconazole and its metabolites showed a trend of increasing and then decreasing in wheat plants under two treatment methods, and the concentration of prothioconazole and its metabolites was higher in the high-concentration group (5000 μg/mL) than in the low-concentration group (1000 μg/mL). The transferability from stem to leaf was stronger than that from root to stem. In the nutrient solution culture, prothioconazole and its metabolites were mainly enriched in wheat roots. The concentration of prothioconazole in wheat roots increases with the increase in prothioconazole concentration and was significantly higher than the prothioconazole concentration on stems and leaves. In wheat leaves in the spraying method, prothioconazole and its metabolites were conducted from leaves to stems and roots up to the nutrient solution. Prothioconazole-desthio was detectable in wheat nutrient solution, while prothioconazole was not detected. Analysis of actual samples of 9 wheat grains and 28 flours showed that the residues of prothioconazole and its metabolites met the maximum residue limit (0.1 mg/mL) set in China and by the Codex Alimentarius Commission. The results will provide a theoretical basis for the scientific use of prothioconazole and food security assurance.

Estimating the influence of bioaccessibility of pesticide residues in fruits and vegetables on dietary exposure is a challenge for human health risk assessment. This study investigated the bioaccessibility of pesticide residues in cherry tomatoes and contributing factors (digestion time, pH, solid/liquid ratio, and dietary nutrition) using an in vitro test simulating the human gastrointestinal tract. pH had the largest effect on triazolone precipitation in the simulated gastric intestinal juice, which had a significant impact on the bioaccessibility. The bioaccessibility of triazolone in the intestinal stage was slightly higher than that in the stomach stage, owing to bile salts and pancreatic enzymes present in the intestinal juice. The bioaccessibility of triazolone did not change significantly with digestion time. In the gastric stage, there was a logarithmic relationship between the bioaccessibility and solid/liquid ratio (R² = 0.9941). The addition of oil significantly changed the bioaccessibility in the gastrointestinal stage. Protein and dietary fiber only affected bioaccessibility in the stomach stage. Dietary nutrition can reduce the release of pesticides from fruits and vegetables into the stomach, sharply reducing the bioaccessibility, and the dietary exposure of pesticide residues in fruits and vegetables can be properly evaluated.

Before being administered as medicinal products, Chinese herbal medicines (CHMs) must be processed and decocted for human consumption. While the presence of pesticide residues in CHMs is a major concern, pesticide dissipation behavior during CHM processing has rarely been reported. In this study, the dissipation of three pesticide residues in the CHM Paeoniae Radix Alba (PRA) was investigated during each step of industrial processing. The boiling process was found to significantly reduce pesticide residues (61–89%), and the peeling process also contributed to pesticide degradation (29–68%). The high temperature (60 °C) during the drying process led to further pesticide degradation. The processing factors of all three pesticides after each processing step were less than one, and the processing factors for the overall process were lower than 0.027, indicating that industrial processing clearly reduced the amount of pesticide residues (97.3–99.4%). The findings provide guidance for the safe use of fungicides in CHMs and can help establish maximum residue limits for PRA to reduce human exposure to pesticides.