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Phenols in soils and agricultural products irrigated with reclaimed water
2021
Li, Yan | Liu, Honglu | Zhang, Lei | Lou, Chunhua | Wang, Yitong
The presence of phenols, such as nonylphenol (NP), bisphenol (BPA), and octylphenol (OP), in the environment have been receiving increased attention due to their potential risks to human health and environment. The use of reclaimed water for irrigation may be one of the sources of these phenols in the agricultural system. A field experiment was conducted to assess the effects of reclaimed water irrigation on phenol contamination of agricultural topsoil and products in the North China Plain between 2015 and 2016. Three irrigation treatments were applied to all crops: reclaimed water irrigation, groundwater irrigation and alternative irrigation with reclaimed water and groundwater (1:1, v/v). The results showed that the concentrations of NP, BPA, and OP in the topsoil were 0.02–0.54, 0.004–0.06, and ND–9.9 × 10⁻³ mg/kg, respectively; the corresponding values in agricultural products were 0.007–0.70, 0.004–0.24, and ND–1.08 mg/kg, respectively. The concentration of NP in the topsoil and agricultural products and that of BPA in the agricultural products were all less than the recommended limits. The yields of wheat, maize, vegetables were 4.35–7.08, 1.03–6.46, and 10.9–67.0 t/ha, respectively. The bioaccumulation factors (BCFs) of OP, NP, and BPA for cereals were 0.7–4.77, 0.16–4.59, and 1.3–23.9, respectively; the corresponding values in vegetables were 0.0–4.53 (except cucumber and eggplant), 0.38–12.6, and 0.57–24.3, respectively. No significant differences in phenol concentrations, BCFs, or yields of wheat and vegetables were observed among the three irrigation treatments. In conclusion, compared with groundwater irrigation, reclaimed water irrigation in this experiment did not significantly affect phenol concentrations in the topsoil and agricultural products as well as BCFs and yields of wheat and vegetables. However, because the quality of reclaimed water may vary across collected areas, additional experiments are warranted to analyze the effects of reclaimed water irrigation on the risk of phenol contamination.
Afficher plus [+] Moins [-]Effect of biochar on Cd and pyrene removal and bacteria communities variations in soils with culturing ryegrass (Lolium perenne L.)
2020
Li, Guirong | Chen, Fukai | Jia, Shengyong | Wang, Zongshuo | Zuo, Qiting | He, Hongmou
Organic contaminations and heavy metals in soils cause large harm to human and environment, which could be remedied by planting specific plants. The biochars produced by crop straws could provide substantial benefits as a soil amendment. In the present study, biochars based on wheat, corn, soybean, cotton and eggplant straws were produced. The eggplant straws based biochar (ESBC) represented higher Cd and pyrene adsorption capacity than others, which was probably owing to the higher specific surface area and total pore volume, more functional groups and excellent crystallization. And then, ESBC amendment hybrid Ryegrass (Lolium perenne L.) cultivation were investigated to remediate the Cd and pyrene co−contaminated soil. With the leaching amount of 100% (v/w, mL water/g soil) and Cd content of 16.8 mg/kg soil, dosing 3% ESBC (wt%, biochar/soil) could keep 96.2% of the Cd in the 10 cm depth soil layer where the ryegrass root could reach, and it positively help root adsorb contaminations. Compared with the single planting ryegrass, the Cd and pyrene removal efficiencies significantly increased to 22.8% and 76.9% by dosing 3% ESBC, which was mainly related with the increased plant germination of 80% and biomass of 1.29 g after 70 days culture. When the ESBC dosage increased to 5%, more free radicals were injected and the ryegrass germination and biomass decreased to 65% and 0.986 g. Furthermore, when the ESBC was added into the ryegrass culture soil, the proportion of Cd and pyrene degrading bacteria Pseudomonas and Enterobacter significantly increased to 4.46% and 3.85%, which promoted the co−contaminations removal. It is suggested that biochar amendment hybrid ryegrass cultivation would be an effective method to remediate the Cd and pyrene co−contaminated soil.
Afficher plus [+] Moins [-]Transportation and degradation of decabrominated diphenyl ether in sequential anoxic and oxic crop rotation
2020
Zhao, Pengfei | Wang, Wei | Whalen, Joann K. | Zhang, Subin | Ye, Qingfu
This work evaluated the debromination and uptake of ¹⁴C-labeled BDE-209 in rice cultivars grown in anoxic soil for 120 days (d) followed by cultivation of vegetables (peanut, eggplant and pepper) in oxic soil (120 d). Degradation of BDE-209 to lower polybrominated diphenyl ethers (PBDEs) occurred in cultivated soils, and more metabolites were released in oxic soil than in anoxic soil. The crop rotation from anoxic to oxic greatly enhanced the dissipation of BDE-209 in the soil (P < 0.05), in which the dissipation in anoxic soil planted with Huanghuazhan (HHZ, indica) and Yudao 1 (YD1, indica) were 6.8% and 2.4%, respectively, while in oxic soil with peanut and pepper were increased to 25.8% and 21.7%, respectively. The crop rotation also enhanced the degradation of BDE-209 in the soil, the recovered BDE-209 in soil after 120 d anoxic incubation with YD1 was 81.1%, but it decreased to 47.8% and 45.8% after another 120 d oxic incubation. Bioconcentration factors were between 0.23 and 0.36 for rice, eggplant and pepper but reached to 0.5 in peanut, which contains more lipids in the edible portion than the other test crops. The estimated daily intake for vegetables was 0.01–0.07 μg BDE-209-equivalent kg⁻¹ bw day⁻¹, which is at least two orders of magnitude below the maximum acceptable oral dose (7 μg kg⁻¹ bw day⁻¹). Our work confirms that crop rotation from rice to vegetable enhanced the dissipation and debromination of BDE-209 in the soil, and indicate that sequential anoxic-oxic rotation practice is considered to be effective in remediation of environmental pollutants.
Afficher plus [+] Moins [-]Cadmium phytoavailability under greenhouse vegetable production system measured by diffusive gradients in thin films (DGT) and its implications for the soil threshold
2018
Tian, Kang | Xing, Zhe | Liu, Guoming | Wang, Huifeng | Jia, Mengmeng | Hu, Wenyou | Huang, Biao
The diffusive gradients in thin films (DGT) technique is recognized to have advantages over traditional techniques. For example, the passive measurement generally follows the principle of metal uptake by plants, and its result incorporates the influences of soil properties, which may make DGT a good protocol for improving soil quality guidelines (SQGs). However, DGT has rarely been applied to assess Cd phytoavailability in soils under greenhouse vegetable production (GVP) systems. In this study, 29 turnips (Raphanussativus L.), 21 eggplants (Solanum melongena L.) and their corresponding soils were collected from GVP systems in Dongtai and Shouguang, eastern China. Simple linear regression and stepwise regression were performed using the soil Cd content and soil properties to predict the vegetable Cd content. Soil thresholds were derived based on both total and available Cd concentrations. The results showed that total Cd, DGT-measured Cd (DGT-Cd), soil-solution Cd (Soln-Cd) and CaCl2-extractable Cd (CaCl2-Cd) were all significantly correlated with vegetable Cd. DGT-Cd had the best correlation with turnip Cd. The total Cd threshold values ranged from 4.87 (pH 6.5) to 5.18 (pH 7.5) mg kg−1 for turnips and 14.60 (pH 6.5) to 14.90 (pH 7.5) mg kg−1 for eggplants. These Cd thresholds were higher than the current SQGs. The predicted of turnip Cd by DGT-Cd was not improved significantly by further considering the soil properties. The calculated soil threshold of DGT-Cd was 5.35 μg L−1 for turnips. However, the predicted soil threshold of DGT-Cd for eggplant was improved by including SOM, with R2 values from 0.53 to 0.70. The DGT-Cd threshold was calculated as 1.81 μg L−1 for eggplant (30.0 g kg−1 SOM). In conclusion, whether DGT measurements are independent of soil properties and preferable for the evaluation of Cd phytoavailability and the generation of soil thresholds remains to be clarified in future research.
Afficher plus [+] Moins [-]The distributions of three fungicides in vegetables and their potential health risks in Zhejiang, China: A 3-year study (2015–2017)
2020
Lin, Shu | Tang, Tao | Cang, Tao | Yu, Shuqing | Ying, Zeteng | Gu, Sijia | Zhang, Quan
Fungicides have been extensively used around the world in agriculture due to their effectiveness of sterilization. Recent evidences have shown that fungicides would exert a negative effect on gut microbiota and result in gut microbiota dysbiosis and metabolism disorder on non-target organisms and even humans. However, research on residues and potential health risks of fungicides in daily consumed vegetables has received less attention compared to insecticides. In this study, we studied three widely applied fungicides, procymidone, dimethomorph, and azoxystrobin, in China. We collected 551 samples of 10 different vegetables in 11 cities from Zhejiang province during 2015–2017. Three fungicides were analyzed by liquid chromatography-tandem mass spectrometry (LC-MS/MS). The average apparent recoveries of three fungicides ranged from 84.2% to 110% with the relative standard deviations lower than 10%. The LOD values of procymidone, dimethomorph, and azoxystrobin was 2, 0.09, and 1 μg/kg, respectively. The levels of procymidone, dimethomorph, and azoxystrobin in those vegetables ranged from ND-875, ND-238, and ND-76 μg/kg, respectively. The highest mean concentrations of procymidone, dimethomorph, and azoxystrobin were found in eggplant (68 μg/kg), spinach (16.4 μg/kg), and kidney bean (4 μg/kg), respectively. Tomato (62.6% of samples), eggplant (44.3% of samples), and cucumber (41.6% of samples) were most frequently detected with fungicides. Solanaceous fruit vegetables have the highest detection rate than other vegetables, and fungicides were most frequently detected in winter. The mean concentrations of three fungicides in different vegetables were all below the maximum residue limits for the national food safety standards of China, and the health risks resulting from consuming those vegetables in adults and children were all within the safe ranges. The data provided here clarify the distributions of fungicides in commonly consumed vegetables and their potential health risks.
Afficher plus [+] Moins [-]A novel and green sulfur fertilizer from CS2 to promote reproductive growth of plants
2020
Yue, Xiaoqing | Wang, Haozhe | Kong, Jing | Li, Bin | Yang, Jinrong | Li, Qiang | Zhang, Jianbin
Carbon disulfide (CS₂) is seen an odor-toxic organic sulfur compound, which presents a major impact on global climate change. Therefore, the conversion of CS₂ into valuable chemicals is the key to reduce the concentration of CS₂ in the atmosphere. On the basis of a CS₂ fixation strategy, CS₂-storage materials (CS₂SMs) are firstly synthesized by the reaction of CS₂ with a binary ion-like liquid systems of ethylenediamine (EDA) and ethylene glycol derivatives (EGs) under mild condition. In view of the serious shortage of sulfur fertilizer and its important position in global agricultural production, it is a promising choice to use the CS₂SMs as a new type of green sulfur fertilizer to promote the growth of eggplant, tomato, sweet pepper and cucumber. In this work, the influence of CS₂SMs on the growth of plants were studied by taking plants irrigated by using various aqueous CS₂SMs solutions as experimental groups, and those irrigated by using water and NH₄HCO₃ as control groups. The experimental results showed that all CS₂SMs could promote plant height, stem diameter, root weight, flower bud number and leaf size. Especially, several CS₂SMs presented significant influence on fluorescence and fruit number. Further studies showed that the CS₂SMs as new energy resources sulfur-containing boosted leaf area, improved root development, enhanced photosynthesis and soil nutrient uptake, and promoted vegetative and reproductive growth of these four types of plants. Thus, this work provided a new strategy for the use of CS₂ as an indirect energy source for the experimental four plants.
Afficher plus [+] Moins [-]Selection for low-cadmium cultivars and cadmium subcellular distribution comparison between two selected cultivars of eggplant (Solanum melongena L.)
2021
Shen, Chuang | Fu, Huiling | Liao, Qiong | Huang, Bai-Fei | Huang, Ying-Ying | Xin, Jun-Liang
Excessive accumulation of cadmium (Cd) in vegetables poses a serious threat to human health; therefore, it is urgent to screen and cultivate vegetable cultivars with low Cd accumulation in the edible parts. Eggplant has a high tendency for Cd accumulation, but research on its low Cd accumulation cultivars is still rare. In this study, to screen low-Cd cultivars, 30 eggplant cultivars were screened using soils containing 0.22 mg/kg, 2.9 mg/kg (low-Cd), and 4.7 mg/kg of Cd (high-Cd). MYCQ and ZGQ were confirmed as low-Cd cultivars, BXGZ and WCCQ were confirmed as high-Cd cultivars, and a 2.52–3.88-fold difference in Cd concentration was observed in their fruits. The subcellular distribution revealed that the root cell wall and vacuole Cd concentrations of a typical low-Cd cultivar (MYCQ) were significantly higher than those of a typical high-Cd cultivar (BXGZ); however, the Cd concentrations in the cell wall and vacuole in fruits, leaves, and stems were significantly lower in MYCQ than in BXGZ. These results indicated that the low-Cd cultivars of eggplant could lessen Cd toxicity through the elevated Cd retention and sequestration levels of root cell walls and vacuoles, thus reducing Cd transport from roots to aboveground tissues, leading to low Cd accumulation. The findings of this study can provide a physiological and biochemical foundation for the screening and breeding of low-Cd cultivars of fruit vegetables and demonstrates that the application of low-Cd cultivars is necessary for food safety in humans.
Afficher plus [+] Moins [-]The potential impact of Octopus cyanea extracts to improve eggplant resistance against Fusarium-wilt disease: in vivo and in vitro studies
2021
The novelty of the present research is conducting a new method in the systemic resistance of plant diseases by using distinct marine extracts. The ability of two octopus extracts to reduce the wilt disease caused by Fusarium oxysporum was observed. The applied methods are soaked roots (SR) and foliar shoots (FS). The antioxidant enzyme activities, percent disease index (PDI), and growth parameters were measured. In vitro antifungal potential of the octopus extracts against F. oxysporum was examined. The obtained result shows that SR extracts reduced PDI. Additionally, all the tested treatments promoted the growth and photosynthetic pigments of the infected plants. SR (in ethanolic extracts) was the most prominent inducer which offered a high advancement in the total soluble protein contents. Also, SR (in methanolic extracts) was the most suitable inducer which provided a very necessary development not only in the total phenol but also in the peroxidase (POD) and polyphenol oxidase (PPO) activities. GC-MS investigation of the octopus extracts exhibited that the compounds which possess antifungal activity were furoscrobiculin B and/or eugenol. They demonstrated a notable antifungal potential against F. oxysporum with a maximum activity of 38.5 and 12.7 mm ZOI after the treatment with the ethanolic and methanolic extract, respectively. FTIR results illustrated the functional group of the compound responsible for the antifungal activity. Additionally, an atomic absorption result reveals that there are traces of metals detected such as Pb, Ag, Cu, Zn, and Mg. The antifungal activity was decreased as the concentrations were reduced. Accordingly, the present extracts may be used as the vital agents in the agricultural field to restrain the plant pathogenic fungi, especially F. oxysporum from a proliferation.
Afficher plus [+] Moins [-]Application of smart irrigation systems for water conservation in Italian farms
2021
Casadei, Stefano | Peppoloni, Francesco | Ventura, Flaminia | Teodorescu, Razvan | Dunea, Daniel | Petrescu, Nicolae
In many countries, water supplies are limited and must be managed for different uses. Providing additional resources for irrigation can be an expensive option, with an unsustainable impact on small farms and on the environment. Therefore, the main efforts should concentrate on the optimal management of existing water resources, paying particular attention to the adequate management of water demands. In Italy, the majority of scattered smallholder farmers are not provided with enough information on how to correctly manage water for irrigation. This paper presents the developing of a web-based irrigation decision support system adaptable and scalable to individual farms. The irrigation advisory service has been calibrated and validated for pomegranate trees, aubergine, and zucchini through 2 years of tests, in a farm in Southern Italy (Calabria). The results are very satisfactory, both in terms of water resources management for irrigation, and for the feedback provided by the farmers involved in the project. Future development regarding the application of wireless technology in smart irrigation is also evaluated.
Afficher plus [+] Moins [-]Dietary intake assessment of pyrethroid residues from okra and eggplant grown in peri-urban areas of Punjab, Pakistan
2020
Amjad, Adnan | Randhawa, Muhammad Atif | Javed, Muhammad Sameem | Muhammad, Zafarullah | Ashraf, Mussawar | Ahmad, Zulfiqar | Murtaza, Shamas
This study was designed to assess the gradual increase in the use of insecticides on vegetables and to familiarize the consumers regarding the insecticide residues. The purpose of this research work was to highlight the detrimental effects of pyrethroids (bifenthrin, cyfluthrin, cypermethrin, deltamethrin, fenvalerate, lambda-cyhalothrin, and permethrin) compare with dietary intake assessment of eggplant and okra grown in peri-urban environment. In this manner, a total of 180 (n = 60 × 3) samples of eggplant (Solanum melongena) and okra (Abelmoschus esculentus) were procured from the peri-urban farming system of Faisalabad, Multan, and Gujranwala to assess the pyrethroid residues along with their dietary intake assessment. The procured vegetables were quantified for pyrethroid residues by using gas chromatography (GC) equipped with an electron capture detector (ECD). Outcomes of this study revealed that for okra samples, the highest residues of bifenthrin (1.25 mg kg⁻¹) were found in Gujranwala then Multan (1.5 mg kg⁻¹) and Faisalabad (1.04 mg kg⁻¹), whereas in eggplant, the highest residues were recorded for bifenthrin from Faisalabad (1.33 mg kg⁻¹) and Gujranwala (0.78 mg kg⁻¹). In Multan, the highest residues for cyfluthrin (1.18 mg kg⁻¹) were reported in eggplant. Out of all analyzed samples for pyrethroid residues, 32% samples contained detectable residues and 6% samples exceeded their maximum residual limits (MRLs) established by the European Union (EU). Dietary intake assessment (mg kg⁻¹ day⁻¹) was calculated as per their maximum permissible intake (MPI) values, i.e., bifenthrin (1.28), cyfluthrin (1.28), cypermethrin (3.20), deltamethrin (0.64), fenvalerate (1.28), lambda-cyhalothrin (0.064), and permethrin (3.20) respectively. Conclusively, residues from the Multan region were greater than those from Gujranwala and Faisalabad showing excessive application of pyrethroids. Overall results revealed that although some samples exceeded MRLs in selected areas, their safe consumption limit was found.
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