Search

This study aimed to investigate the effects of exogenous copper and ethylene on resveratrol biosynthesis in peanut buds. In this study, different concentrations of copper sulfate and ethephon were used to induce peanut bud roots. Resveratrol content was determined using high‐performance liquid chromatography (HPLC). The interaction effects of the two inducers were analyzed using regression and response surface methodology. Results showed that resveratrol biosynthesis increased with the increase in copper sulfate concentration. Resveratrol synthesis showed an increasing trend when the concentration of ethephon was from 5 to 7 mmol/L. The resveratrol content reached a maximum value of 7.7 μg/g when the concentration of ethephon was 7 mmol/L and then decreased with an increase in ethephon. Response surface analysis revealed that the combination of 0.1 mmol/L copper sulfate and 5 mmol/L ethephon was effective and resulted in the induction of resveratrol biosynthesis in peanut buds., For this research, the change of copper sulfate concentration is from 0.1 to 0.5 mmol/L, and the change of ethephon concentration is from 2 to 9 mmol/L. In such an induction range, when inducing resveratrol biosynthesis in peanut bud, in more cases, the two elicitors showed synergistic effect and increased resveratrol biosynthesis.

Occurrence, behavior, and fate of 11 OPEs in multiple environmental matrices, which include air, rainwater, dustfall, paddy soil, irrigation water, and rice plants from nine subtropical paddy fields of South China, were investigated. The total concentrations of 11 OPEs (∑11OPEs) in all matrices are generally higher in the urban areas than in rural areas, and they are higher in summer than in fall. However, both urban and rural areas showed a similar composition profile of OPEs, indicating that the OPEs come from similar sources in the two areas. Except for irrigation water, significant positive correlations of ∑11OPEs were observed between air and the other five matrices. The exchange and partition of OPEs among air, soil, and water demonstrate that most of OPEs were transferred from air into water and soil, and from water into soil. Thus, the air may be an important source of OPEs in the paddy fields, and the soil may act as a principal environmental reservoir of OPEs. The contribution of air-soil exchange, atmospheric deposition (rainwater plus dustfall), and irrigation water to the total input fluxes of OPEs (2100 ± 980 ng/m2/day) reached an average of 19%, 38% (37% + 1%), and 43%, respectively. The water (rainwater plus irrigation water) is the primary medium transferring the OPEs into the paddy fields and contributed to the input flux by 80%. Output flux of OPEs via mature rice plants was about 220 μg/m2, 2% of which were presented in rice, and the remaining 98% may be re-released into the environment through the pathway of straw turnover or burning. Dietary exposure via rice was much higher than inhalation exposure, dust ingestion, and dermal absorption via dust. However, no data shows that all of the intakes via the four exposure pathways could cause the risks to human health at present.

This work studies the adsorption and degradation of 2,4-dichlorophenoxyacetic (2,4-D) in spiked soil with nanoscale Fe0 particles (nFe0) and biochar derived from maize straw. When biochar concentration was high, the adsorption capacity of soil was enhanced. Furthermore, 2,4-D degraded completely at loading rates of 0.33 and 0.17 g/L nFe0 plus biochar (initial 2,4-D concentration of 10 mg/g) within 40 h, according to equilibrium data. Additionally, the theoretical concentration of chloridion was approximately 84%. Further analysis indicated that the effect of nFe0 on 2,4-D degradation was weaker in soil columns than that in soil slurry. By contrast, 2,4-D degradation is positively influenced by biochar application, which prevented the aggregation and corrosion of Fe nanoparticles. Although the enhanced capacity for 2,4-D adsorption on the soil decelerated dechlorination rate, long-term nFe0 activity was generated. After 72 h, the efficiency of 2,4-D degradation was approximately 53.2% in the soil columns w...