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E or pyriminobac-methyl (EPM), a pyrimidine benzoic acid esters herbicide, has a high potential as weedicide; nevertheless, its environmental behaviors are still not well understood. In this study, we systematically investigated, for the first time, the adsorption–desorption, degradation, and leaching behaviors of EPM in agricultural soils from five exemplar sites in China (Phaeozems – S1 ; Anthrosol – S2 ; Ferralsol – S3 ; Alisol – S4 ; Plinthosol – S5) through laboratory simulation experiments. Our results show that the EPM adsorption–desorption results were well fitted by the Freundlich model (R2>0.9999). In the analyzed soils, the Freundlich adsorption (i.e., Kf ads) and desorption (i.e., Kf des) coefficients of EPM varied between 0.85 and 32.22 mg 1-1/n L 1/n kg -1 and 0.78–5.02 mg 1-1/n L 1/n kg -1 , respectively. The mobility of EPM in soils S1 – S5 was categorized as immobile, slightly immobile, highly mobile, slightly mobile, and slightly mobile, respectively. Moreover, the degradation of EPM reflected first-order kinetics, where its half-life ranged between 37.46 and 66.00 d, depending on the environmental conditions, and abiotic degradation was predominant in the degradation of this compound. Overall, the high leaching ability and desorption capacity of EPM were accompanied by a low adsorption capacity, and there were no significant relationships between pH and the leaching rate of EPM in the five types of soils. In contrast, the organic matter content, cation exchange capacity, and soil clay content were the main components responsible for the observed leaching rates. We found that EPM degrades easily, has a high adsorption affinity, and a low mobility in S1 , which results in a low contamination risk for groundwater systems. On the contrary, this compound degrades slowly in S2 , S3 , S4 , and S5 , due to a low adsorption affinity and moderate mobility, which results in a high contamination risk for groundwater systems. Therefore, our results may serve as a reference for evaluating the risks involved in the increasingly wide application of this compound. [ABSTRACT FROM AUTHOR]

Cyanogen (C 2 N 2) is a new and effective alternative soil fumigant to methyl bromide. The effects of soil properties on the fate of C 2 N 2 and its degradation products, including hydrogen cyanide (HCN), are not fully understood. The objectives of this study were to determine the adsorption kinetics, adsorption isotherms, and degradation kinetics of C 2 N 2 and HCN in texturally different soils and evaluate their leaching potentials using soil columns. Eight agricultural soils were collected throughout China: Luvisols (Hebei Province), Phaeozems (Heilongjiang Province), Gleysols (Sichuan Province), Anthrosols (Zhejiang Province), Ferralsols (Jiangxi Province), Lixisols (Hubei Province), Alisols (Shandong Province), and Plinthosols (Hainan Province). The adsorptions of C 2 N 2 and HCN in C 2 N 2 -fumigated soils were positively correlated with organic matter and clay contents. For a C 2 N 2 dose of 100 mg kg−1, the adsorptions of C 2 N 2 and HCN were highest in Phaeozems and lowest in Gleysols according to their adsorption coefficients (15.744 and 3.119, respectively). No significant difference in the half-life of C 2 N 2 and HCN was observed between sterilized and unsterilized soils, indicating that abiotic degradation was predominant in the degradation of C 2 N 2 and HCN. After leaching, the residual C 2 N 2 , HCN, NH 4 +–N, and NO 3 −–N concentrations in C 2 N 2 -fumigated Phaeozems were highest within 15 cm of the soil surface (30, 20, 19.68, and 10.41 mg kg−1 soil, respectively). The results indicate that C 2 N 2 and HCN have short lifetimes and low leaching potentials in agricultural soils, even under heavy rainfall conditions. The findings demonstrate that C 2 N 2 and HCN resulting from fumigation will not accumulate in the soil and are not likely to contaminate groundwater. • Adsorption, degradation, and leaching of C₂N₂ and HCN in eight soils were tested. • C₂N₂ and HCN adsorptions were correlated with organic matter and clay contents. • For a C₂N₂ dose of 100 mg kg⁻1, C₂N₂ and HCN adsorptions were highest in Phaeozems. • Abiotic degradation was predominant in the degradation of C 2 N 2 and HCN. • C 2 N 2 /HCN will not accumulate in soil and are not likely to contaminate groundwater. [ABSTRACT FROM AUTHOR]

Locusta migratoria is a serious agricultural pest in China. Beauveria bassiana is one of the most important pathogens of grasshoppers and locusts. The effects of ultraviolet light were evaluated on the B. bassiana strain BbZJ1. The results showed that 253.7 and 360 nm wavelength UV (Ultra Violet) did not affect the germination of B. bassiana after its recovery from UV treatments. Nevertheless, the virulence of B. bassiana BbZJ1 after its recovery from radiation of UV (253.7 nm) increased. The mortality rates were 85.00% for the BbZJ1 control, was 96.67% for BbZJ1 recovered from radiation of UV (253.7 nm) for 60 min. After treatment with 253.7 nm UV radiation for 60 min, the expression levels of stress-resistant genes BbAlg9 and Bbadh2 in BbZJ1 strain were 2.68 and 2.29 times higher than those in the control group, respectively. Meanwhile, the B. bassiana prepared in 5% groundnut oil showed highest tolerance levels to the ultraviolet radiation. The 5% groundnut oil was the most suitable potential UV-protectant for B. bassiana in terms of cost and availability., (© 2023. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

Tetraniliprole (TTP) is a new bisimide-based insecticide. Three typical surface soil samples were collected in farmland across China, including Jiangxi red soil (RS), Shandong yellow brown soil (YBS), and Heilongjiang black soil (BS). Adsorption, desorption and leaching experiments were conducted by using equilibrium oscillation and soil column leaching methods at 25°C ± 1°C. The isothermal adsorption and desorption curves of TTP in the above three soils were in accordance with the Freundlich model. The adsorption/desorption constants (K ads-f /K des-f ) were 41.96-64.48 and 3.62-43.65, respectively. There is a certain hysteresis in the desorption curve, and the hysteresis coefficient (H) was between 0.14 and 0.89. Besides, the leaching properties of TTP in three soils were different. The leaching of TTP in RS and YBS was easy, while difficult for BS. It is concluded that the different adsorption-desorption ability and leaching ability of TTP in the above three soils was attributed to the distinct contents of organic matter (OM) and cation exchange capacity (CEC) in soil.