Toxicity on soil bacterial community growth caused by the antibiotics oxytetracycline (OTC) and chlortetracycline (CTC) was studied in 22 agricultural soils after 1, 8 and 42 incubation days. The leucine incorporation method was used with this aim, estimating the concentration of each antibiotic which caused an inhibition of 50% in bacterial community growth (log IC₅₀). For OTC, the mean log IC₅₀ was 2.70, 2.81, 2.84 for each of the three incubation times, while the values were 2.05, 2.22 and 2.47 for CTC, meaning that the magnitude of OTC toxicity was similar over time, whereas it decreased significantly for CTC with incubation time. In addition, results showed that the toxicity on bacterial community growth due to CTC is significantly higher than when due to OTC. Moreover, the toxicity on bacterial community growth due to both antibiotics is dependent on soil properties. Specifically, an increase in soil pH and silt content resulted in higher toxicity of both antibiotics, while increases in total organic carbon and clay contents caused decreases in OTC and CTC toxicities. The results also show that OTC toxicity can be well predicted by means of specific equations, using the values of pH measured in KCl and those of effective cation exchange capacity as input variables. CTC toxicity may be predicted (but with low precision) using pH measured in KCl and total organic carbon. These equations may help to predict the negative effects caused by OTC and CTC on soil bacteria using easily measurable soil parameters. Full article

The purpose of this study was to investigate whether combining plastic-covered ridge and furrow planting (RF) and supplemental irrigation based on measuring soil moisture (SIMSM) can increase the grain yield and water use efficiency (WUE) of wheat (Triticum aestivum L.) in irrigated fields of Loess Plateau, China. In 2016–2018, the experiment was conducted at Doukou experimental farm (34°36′ N, 108°52′ E) with two plant systems (RF and traditional planting (TF)) and three irrigation treatments (S1 and S2: SIMSM with a target relative soil water content of 85% and 100%, respectively). The results suggest that under the TF system, SIMSM decreased the grain yield and nitrogen utilization. The reason for this may be the local low precipitation. However, the combination of RF and S2 significantly increased the WUE, protein and wet gluten concentration in the grain. In addition, the grain yield of the RF plus S2 treatment was not significantly different than that of the traditional irrigation method. These results suggest that combining RF and SIMSM with a target relative soil water content of 100% is beneficial to the synergistic improvement of the wheat yield, the wheat quality, and the water and fertilizer use efficiency in irrigated fields on the Loess Plateau. Full article

In broccoli production a big challenge is preparation of seedlings, which must be delivered during a strictly defined period to vegetable producers that are often in distant places. The goal of the present study was to investigate the response of 5-week old broccoli transplants cv. Parthenon F₁ to 2 and 6 weeks of storage at 4 °C under two LED light spectra (L1: 29% red 660 nm + 14% red 630 nm + 42% blue 250 nm + 15% green 520 nm and L2: 38% red 660 nm + 18% red 630 nm +26% blue 450 nm + 15% green 520 nm + 3% UV-A 330 nm; photoperiod 16/8 h day/night and PPFD 30 ± 10 µmol m⁻² s⁻¹) and darkness. Control 5-week-old seedlings were not stored. Light treatment improved the morphology and physiological parameters of seedlings. The yield of broccoli from control seedlings was similar to that obtained after L2 treatment, regardless of seedling storage duration. The most promising effects were obtained by adding 3% UV-A radiation to the lighting spectrum. The results are applicable to the transport of broccoli transplants to remote locations or storage for several weeks, in cases where it is necessary to delay planting. Full article

The common bean (Phaseolous vulgaris L.) is a grain legume functionally characterized by its capacity for symbiotic of biological nitrogen fixation. As such, it does not demand the application of synthetic nitrogenous fertilizer and can offer environmental benefits as part of holistic cropping systems. While common bean commodities are highly nutritious, commercial cultivation of this crop is declining in already-industrialized countries. However, recent interest of consumers towards diets that benefit environmental and personal health has rekindled commercial interest in legumes, including the common bean. The aim of this protocol is to identify agronomic practices that are capable of increasing the yield and quality of the common bean for use as food. To address this research question, published literature will be screened for inclusion on the basis of defined eligibility criteria to ensure data sources are selected in an objective and consistent manner. Consistency checks will be carried out for the title, abstract and full texts of the literature collated. The output is expected to be a summary of the knowledge available to maximize the productivity and quality of the common bean as food. This anticipated synthesis will be of utility for a wide range of value-chain stakeholders from farmers and consumers, to research scientists and policy makers. Full article

To improve sward efficiency and maintain high feed quality in organic farming—as well as compensate for yield losses under anticipated drought periods—alternative fertilization practices should be considered. In this context, this study aimed to assess the response to summer drought of grass–clover sward in organic cultivation under various conditions of foliar fertilization with silicon (Si) (without Si, Si applied with multicomponent fertilizer Herbagreen, Si applied with growth stimulator Optysil). The research was conducted at the certified organic field in the 3rd, 4th and 5th year of mowing utilization (from 2015 to 2017). The studies demonstrated a beneficial effect of Si application on the yield of the grass–clover sward, especially under multicomponent fertilizer. Both fertilizers increased roots mass, but growth stimulator (containing mainly Si) had a stronger impact, especially with rainfall scarcity. In such conditions the application of Si decreased flavones concentration in plants and increased values of chlorophyll index. This study also indicated the potential for applying Si fertilizers to improve content of nutrients (crude protein, organic matter digestibility, potassium and phosphorus) in the sward. The results of presented studies may be used in fertilization practice of organic crop for enhancing sward productivity and to compensate for yield losses under condition of rainfall deficiency. Full article

Plant growth-promoting rhizobia are known to improve crop performance by multiple mechanisms. However, the interaction between host plants and Rhizobium strains is highly influenced by growing conditions, e.g., heat, cold, drought, soil salinity, nutrient scarcity, etc. The present study was undertaken to assess the use of Rhizobium as plant growth promoters under abiotic stress conditions. Fifteen Rhizobium strains isolated from lentil root nodules were tested for phosphate solubilization activity (PSA) and phytohormones production under salt and drought conditions. The results showed that 15 Rhizobium strains were significant phosphate solubilizers, and indole acedic acid (IAA) and gibberellic acid (GA3) producers based on least significant difference (LSD) analysis (p ≤ 0.05). The highest rate of PSA was attributed to three strains namely, 1145N5, 1159N11, and 1159N32 with a range of 144.6 to 205.6 P₂O₅ (µg/mL). The highest IAA production was recorded in the strain 686N5 with 57.68 ± 4.25 µg/mL as compared to 50.8667 ± 1.41 µg/mL and 37.32 ± 12.59 µg/mL for Rhizobium tropici CIAT 899 and Azospirillum brasilense DSM-1690, respectively. Strain 318N2111 produced 329.24 ± 7.84 µg/mL of GA3 as against 259.84 ± 25.55 µg/mL for A. brasilense DSM-1690. R. tropici CIAT 899 showed tolerance to salt (5% NaCl) and drought (ψ = −2.6 MPa) stress, whereas strain 686N5 showed an extremely high level of salt-tolerance (5% NaCl) and moderate level of drought tolerance (ψ = −0.75 MPa). These results indicate different pathways for drought and salt tolerance mechanisms. The assessment of plant growth promoting (PGP) activities of Rhizobium showed differences between bacterial viability and bacterial PGP activity in terms of abiotic stress tolerance where bacterial PGP activity is interrupted before reaching the bacterial tolerance threshold. These results integrate a new concept of PGPR screening based on PGP activity under abiotic stress. Full article

Due to climate change the productive agricultural sectors have started to face various challenges, such as soil drought. Biochar is studied as a promising soil amendment. We studied the effect of a former biochar application (in 2014) and re-application (in 2018) on bulk density, porosity, saturated hydraulic conductivity, soil water content and selected soil water constants at the experimental site in Dolná Malanta (Slovakia) in 2019. Biochar was applied and re-applied at the rates of 0, 10 and 20 t ha⁻¹. Nitrogen fertilizer was applied annually at application levels N0, N1 and N2. In 2019, these levels were represented by the doses of 0, 108 and 162 kg N ha⁻¹, respectively. We found that biochar applied at 20 t ha⁻¹ without fertilizer significantly reduced bulk density by 12% and increased porosity by 12%. During the dry period, a relative increase in soil water content was observed at all biochar treatments—the largest after re-application of biochar at a dose of 20 t ha⁻¹ at all fertilization levels. The biochar application also significantly increased plant available water. We suppose that change in the soil structure following a biochar amendment was one of the main reasons of our observations. Full article

The main objective of this study was to determine the capacity of Trichoderma aggressivum f. europaeum to promote pepper and tomato seedling growth compared to that of T. saturnisporum, a species recently characterised as a biostimulant. Consequently, in vitro seed germination and seedling growth tests were performed under commercial plant nursery conditions. Additionally, the effects of different doses and a mixture of both species on seedling growth under plant nursery and subsequently under greenhouse conditions were determined. Furthermore, mass production of spores was determined in different substrates, and their siderophore and indole acetic acid production and phosphate (P) solubilisation capacity were also determined. Direct application of Trichoderma aggressivum f. europaeum to seeds in vitro neither increases the percentage of pepper and tomato seed germination nor improves their vigour index. However, substrate irrigation using different doses under commercial plant nursery conditions increases the quality of tomato and pepper seedlings. Tomato roots increased by 66.66% at doses of 10⁶ spores per plant. Applying T. aggressivum f. europaeum or T. saturnisporum under plant nursery conditions added value to seedlings because their growth-promoting effect is maintained under greenhouse conditions up to three months after transplantation. The combined application of the two species had no beneficial effect in relation to that of the control. The present study demonstrates the biostimulant capacity of T. aggressivum f. europaeum in pepper and tomato plants under commercial plant nursery and greenhouse conditions. Full article

Aims: Biological nitrification inhibition (BNI) has been reported as an emerging technology to control soil nitrifier activity for effective N-utilization in cropping systems. Brachiaria have been reported to suppress nitrifier populations by releasing nitrification inhibitors from roots through exudation. Substantial BNI activity has been reported to be present in the root tissues of Brachiaria grasses; however, BNI contribution, such as root turnover, has not been addressed in previous studies. The present study aimed to clarify the contribution of root turnover on BNI under Brachiaria cultivations and its impact on nitrifier populations. Methods: We monitored root growth, changes in ammonia-oxidizing bacteria (AOB) and ammonia-oxidizing archaea (AOA) numbers, nitrification rate, and available nitrogen (N) content under seven germplasm lines of Brachiaria, for 18 months with seasonal profile sampling. Results: Brachiaria cultivation increased soil NH₄⁺-N, available N, and total soil carbon levels. Though we did not find any correlation between the changes in AOB populations and potential nitrification, the potential nitrification rate decreased when AOA populations decreased. Multiple regression analysis indicated that BNI substances from root tissue turnover had a significant contribution to the BNI function in the field. Conclusion Results indicated that the inhibitory effect of BNI was mostly evident in AOA, and not in AOB, in this study. Brachiaria cvs. ‘Marandu’, ‘Mulato’, and ‘Tupy’ had the most substantial BNI effect among the seven cultivars evaluated. The estimated total BNI activities and available N content of root tissue explained the observed nitrification inhibition. In conclusion, the release of BNI substances through plant decomposition contributes to the decrease in the abundance of AOA, and thus the inhibition of nitrification under Brachiaria cultivation. Full article

In Northern Europe, the use of light–emitting diodes (LEDs) is widely adopted in protected horticulture, enabling to enhance plant growth by ensuring needed radiative fluxes throughout seasons. Contrarily, the use of artificial lighting in Mediterranean greenhouse still finds limited applications. In this study, the effects of supplemental LED interlighting on vegetative development, fruit growth, yield, and fruit quality of high-wire tomato plants (Solanum lycopersicum L. cv. ‘Siranzo’) during spring and summer season were addressed in a hydroponic greenhouse in Italy. Plants were either grown under natural solar radiation (control), or by adding supplemental LED interlighting. LED treatment featured red (R) and blue (B) light (RB ratio of 3) and a photosynthetic photon flux density of 170 µmol m⁻² s⁻¹ for 16 h d⁻¹. Supplemental LED interlighting enhanced yield as a result of increased fruit weight and dimension. While no effects on soluble solids content and fruit color at harvesting were observed, supplemental LED interlighting accelerated ripening by one week in spring and two weeks in summer and this also resulted in increased cumulated productivity (+16%) as compared to control treatment. Overall, supplemental LED interlighting can represent a feasible technology for tomato greenhouse production also in the Mediterranean region. Full article

Purslane (Portulaca oleracea L.) is a wild edible plant, traditionally consumed in the Mediterranean area and recently proposed as a new ready-to-eat vegetable; it is also called the “vegetable for long life” because of the high contents of several healthy compounds. Although boron (B) is not considered to be essential for humans, a daily intake of about 2 mg to obtain positive effects on aging in adult men and women has been suggested. In this study, two genotypes of purslane (wild collected and commercial variety) are grown by using a hydroponic system with three boron (B) levels in the nutrient solution (NS) (0.3 mg/L—control, 3 mg/L—low level of biofortification, and 6 mg/L—high level of biofortification) in order to increase the B content in the edible parts of the plant. The crop yield, color traits, and content of glucose, fructose, total phenols, chlorophylls, carotenoids, mineral elements (Al, B, Ca, Cr, Fe, K, Mg, Mn, Na, and Zn), nitrate, and oxalate are analyzed. Independent of the genotype, the B content in edible purslane was successfully increased in comparison with the control, obtaining 1.8- to 10.7-fold higher values of B tissue concentrations by using, respectively, 3 and 6 mg/L of B in the NS without affecting crop performances. From a nutritional point of view, the average daily intake of B could be satisfied by consuming about 75 or 48 g of purslane, grown by using 3 and 6 mg/L B level in the NS, respectively. Apart from B and Fe, the content of mineral elements in edible parts of purslane was not strongly influenced by different B levels in the NS but it was affected by genotypes. A lower sugar content was found in wild purslane grown with the highest B level. A higher content of both chlorophylls and carotenoids was found in the control but only for the commercial genotype. No differences in oxalate content were observed among B levels in the NS, while only in the case of wild genotype, we found a lower nitrate content when a B concentration of 3 mg/L was used in the NS. In conclusion, we demonstrated the possibility of using the floating hydroponic system, combined with specific B concentrations in the NS composition, as a method to calibrate the B uptake in edible parts of purslane. Full article

A lot of national and international effort has been made to promote sustainable agricultural production systems in drylands. However, success has been seriously limited due to lack of thorough characterization of the impact of the diversity of farm household types on productivity, resource-use efficiency and economic and nutritional status. This study applied hierarchical ascendant classification to a random sample of 286 cereal-producing farm households in Morocco and identified distinct household typologies. It also carried out an analysis of trade-offs between economic, nutritional and environmental factors induced by the production decisions of the different farm household typologies. Our analysis identified three dominant farm household typologies in the production system, namely: (i) intensive predominantly-vegetable farming households with high input intensities, (ii) semi-intensive cereal mono-crop farming households with moderate input intensities and (iii) extensive mixed cereal-legume farming households with low input intensities. Extensive mixed cereal-legume farming households exhibited the highest resource-use efficiency and high biodiversity. These benefits, however, came at the expense of a much lower farm income and limited food supplies relative to the other two systems. These results show that, as is the case for many dryland regions, all three farm types showed precarious conditions for one or more of the sustainability-related indicators. Full article

Nanoparticles (NPs) significantly modify the physiological functions and metabolome of plants. The purpose of the study was to investigate the effect of CeO_2, Fe₂O₃, SnO₂, TiO₂, and SiO₂ nanoparticles, applied in foliar spraying of oakleaf lettuce at concentrations 0.75% to 6%, on the antioxidant enzyme activity and content of non-enzymatic antioxidants, chlorophyll pigments, fresh weight (FW) and dry weight (DW). It was found that 3% Fe₂O₃-NPs caused a 27% decrease in fresh weight compared to control plants. Fe₂O₃-NPs caused an increase in dry weight (g 100 g⁻¹ FW) when compared to the control for all concentrations, but total DW (g per plant) was similar for all NPs treatments. Significant increases in chlorophyll a + b content after treatment with 1.5% and 6% SiO₂-NPs, 3% Fe₂O₃-NPs, and 3% TiO₂-NPs were noted. Fe₂O₃-NPs caused a significant increase in the activity of ascorbate peroxidase, guaiacol peroxidase, and catalase (only for 3% Fe₂O₃-NPs). SnO₂-NPs decreased ascorbate peroxidase (APX) and guaiacol peroxidase (GPOX) activity (for all tested concentrations) but increased catalase (CAT) activity when a 3% suspension of these NPs was applied. The level of glutathione (GSH) increased due to application of all metal/metalloid oxides, with the exception of SnO₂-NPs. When all concentrations of TiO₂-NPs were applied, L-ascorbic acid increased significantly, as well as increasing at higher concentrations of SiO₂-NPs (3% and 6%) and at 0.75% and 3% Fe₂O₃-NPs. SiO₂-NPs and TiO₂-NPs significantly elevated the carotenoid and total phenolic content in treated plants compared to the control. The total antioxidant capacity of plants treated with 3% CeO₂-NPs was almost twice as high as that of the control. Full article

Wine lees are defined as the sediment formed at the bottom of the tank or barrel after wine alcoholic fermentation. They have a heterogeneous composition and currently constitute 6% of the byproducts generated by each ton of wine grapes. However, it is the most under-researched of all the byproducts of the winemaking process. Therefore, with the aim of highlighting this byproduct, a physicochemical and nutritional characterization of winemaking lees from three different wine making processes (white, rosé, and red winemaking) was carried out. In addition, the technological properties of these winemaking lees were also analyzed. The lees analyzed in this research demonstrated an interesting nutritional and heterogeneous composition. Moreover, wine lees showed high values of emulsifying capacity. Thus, winemaking lees could be considered, in a preliminary way, as a new ingredient to be included in new food formulations. Full article

The present study aimed to reveal the impact of the stay-green trait in bread wheat under terminal heat stress. Field experiments (early and late sowing; for two consecutive years) were conducted to investigate the influence of terminal heat stress on the morpho-physiological traits in different stay-green types i.e., non-stay-green, moderately non-stay-green, moderately stay-green, and stay-green. In addition, the greenhouse experiment was performed to dissect the stay-green trait in functional stay-green, non-functional stay-green, and non-stay-green genotypes. The results of the field experiments confirmed that genotypes exhibiting the stay-green trait have a significantly high chlorophyll content, normalized difference vegetative index, grain yield, biological yield, kernel weight, and low canopy temperature under control and heat stress conditions. In the greenhouse experiment, functional stay-green and non-functional stay-green genotypes showed a high chlorophyll content and photochemical efficiency, whereas biological yield and grain yield showed a significant relation with the functional stay-green genotype under control and terminal heat stress treatments. The sequencing and expression analysis of chlorophyllide a oxygenase (CaO), light-harvesting complex (Cab), stay-green (SGR), and red chlorophyll catabolite reductase (RCCR) in functional stay-green, non-functional stay-green, and non-stay-green genotypes revealed variations in the exons of CaO and RCCR; and significant difference in the regulation of CaO and Cab at 7 days after anthesis under terminal heat stress. This study confirms that genotypes displaying the stay-green trait can aid wheat breeders to cope with increasing temperature in the impending decades. Full article