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The current study focuses on yield and nutritional quality changes of wheat grain over the last 166 years. It is based on wheat grain quality analyses carried out on samples collected between 1850 and 2016. Samples were obtained from the Broadbalk Continuous Wheat Experiment (UK) and from herbaria from 16 different countries around the world. Our study showed that, together with an increase in carbohydrate content, an impoverishment of mineral composition and protein content occurred. The imbalance in carbohydrate/protein content was specially marked after the 1960’s, coinciding with strong increases in ambient [CO2] and temperature and the introduction of progressively shorter straw varieties. The implications of altered crop physiology are discussed., This work was supported by the Spanish Innovation and Universities Ministry (AGL2016-79868-R; PCIN-2017-007), BBSRC Institute Strategic Programme grants, Designing Future Wheat (BB/P016855/1) and Soil to Nutrition (S2N, BBS/E/C/00I0310), the Long-term Experiments National Capability grant (BBS/E/C/000J0300), the Lawes Agricultural Trust and the Basque Country Government consolidated group programme (IT‐932‐16).

The application of sewage sludge to agricultural fields reduces the need for mineral fertilizers by increasing soil organic matter, but may also increase soil pollution. Previous studies indicate that zinc and copper, as the most abundant elements in sewage sludge, affect plant uptake of other contaminants. This paper aims to investigate and compare the effect of increasing amounts of Zn and Cu in sludge-amended soils on the accumulation of trace elements (TEs), antibiotics (ABs), and antibiotic resistance genes (ARGs) in lettuce and radish. The vegetables were grown under controlled conditions, and the influence on plant physiology and human health were also evaluated. The results show that the addition of Zn and Cu significantly increased the concentration of TEs in the edible tissue of both vegetables. According to the hazard quotient (HQ) of the TEs, the human health risk increased 2 to 3 times and was 3 to 4 times greater in lettuce than in radish. In contrast to the TEs, the occurrence of ABs and most of the ARGs was higher in radish roots than lettuce leaves. ABs were not detected in lettuce leaves, and the amount of all ARGs except blaTEM was 10 times lower than in radish roots. On the other hand, the addition of Zn and Cu had no significant effect on the occurrence of ABs and ARGs in the edible part of the vegetables, and no damage was found to plant productivity or physiology. The results show that the consumption of lettuce and radish grown in sewage-sludge-amended soils under our dosage does not pose an adverse human health effect, as the total HQ value was always less than 1, and the presence of ABs and ARGs was not found to have any potential impact. Nevertheless, further studies are needed to estimate the long-term effect on human health of crops grown under frequent application of biosolids in arable soil., The authors gratefully acknowledge the financial support of the Spanish Ministry of Economy, Industry, and Competitiveness (MEIC) through Project AGL2017-89518-R. Rui You gratefully acknowledges a fellowship from the China Scholarship Council. The authors would further like to thank Mr. M. Massip for his kind assistance at the greenhouse facility.

Soil amendment with organic fertilizers is an effective approach to improve soil fertility. However, organic fertilizers may contain pollutants such as trace elements (TEs) and antibiotics (ABs), which, once deployed in arable soil, can be taken up by vegetables and have adverse effects on crops and human health. This study assesses the presence of 15 TEs and 16 ABs in lettuce grown in a greenhouse facility and amended with 3 different organic fertilizers (sewage sludge (SS), organic fraction of municipal solid waste (OFMSW), and swine manure (SM)) at 3 different fertilization doses. The results show that lettuces amended with SS resulted in the lowest content of TEs. Although 11 ABs were detected in the SM and SS fertilizers, only 3 ABs were detected in lettuce leaves. The concentrations of detected ABs in lettuce ranged from 0.67 ng/g fw (lincomycin) to 14.2 ng/g fw (ciprofloxacin) in SS. The organic fertilization dose did not affect the lettuce uptake of TEs or ABs. Moreover, the use of SS resulted in the highest lettuce yield of the organic amendments. The total hazard quotients (THQs) obtained for TEs and ABs were less than 1 for all the studied fertilization treatments. The highest THQs for TEs were observed in lettuce amended with SM (0.11–0.16), whereas the highest THQs for ABs were observed in SS treatments (0.06–0.09). The results thus suggest that consumption of lettuces amended with organic fertilizers would not pose a risk to human health due to the presence of studied TEs or ABs, but potentially harmful combined effects cannot ruled out., The authors gratefully acknowledge the financial support of the Spanish Ministry of Science and Competitiveness through Project AGL2017-89518-R. Rui You gratefully acknowledges the fellowship from the China Scholarship Council.

Peri-urban horticulture performs environmental and socio-economic functions and provides ecological services to nearby urban areas. Nevertheless, industrialization and water pollution have led to an increase in the exposure of peri-urban vegetables to contaminants such as trace elements (TEs) and organic microcontaminants (OMCs). In this study, the occurrence of chemical contaminants (i.e., 16 TEs, 33 OMCs) in soil and lettuce leaves from 4 farm fields in the peri-urban area of the city of Barcelona was assessed. A rural site, outside the peri-urban area of influence, was selected for comparison. The concentration of TEs and OMCs ranged from non-detectable to 803 mg/kg dw and from non-detectable to 397 μg/kg dw respectively in the peri-urban soil, and from 6 · 10−5 to 4.91 mg/kg fw and from non-detectable to 193 μg/kg fw respectively in lettuce leaves. Although the concentration of Mo, Ni, Pb, and As in the soil of the peri-urban area exceeded the environmental quality guidelines, their occurrence in lettuce complied with human food standards (except for Pb). The many fungicides (carbendazim, dimetomorph, and methylparaben) and chemicals released by plastic pipelines (tris(1-chloro-2-propyl)phosphate, bisphenol F, and 2-mercaptobenzothiazole) used in agriculture were prevalent in the soil and the edible parts of the lettuce. The occurrence of these chemical pollutants in the peri-urban area did not affect the chlorophyll, lipid, or carbohydrate content of the lettuce leaves. PCA (Principal Component Analysis) showed that soil pollution, fungicide application, and irrigation water quality are the most relevant factors determining the presence of contaminants in crops.

e a psi c u m a n n u u m plants under summer field conditions were grown in 17 cm plastic pots with different substrates: (1) Peat-Polystyrene (1:1) (v/v), (2) Composted Pine Bark, (3) Composted Grape Refuse-Olot s Volcanic Ashes (1:1) (v/v), and (4) Peat-Composted Pine Bark-Perlite (1:1:1) (v/v/v). Transpiration rate and stomatal resistance daily variation depended on irradiance and on substrate water contento Plants with one morning irrigation, 2 l/pot, showed stomatic symptoms of water deficit during the morning, in substrate (3), and in the afternoon in the other media. E.A. \rJ. % vol: (1) 22.7; (2) 21.8; (3) 8.0; and (4) 19.1 • Two more irrigations, 1 l/pot each, overcame restrictions of gaseous exchange in substrate (3), increasing ~anspiration rates and decreasing stomatal resistance substantially. Furthermore in _all substrates this three irrigation treatment extended, at least for one hour in the afternoon, the potential gaseous exchange in relation to irradiance assuming photosynthesis and stomatal resistance dependence of photon fluence rateo