Search Results (57)

The sustainable management of organic residues remains a major challenge in agriculture. Vermicomposting offers an environmentally friendly strategy to convert organic waste into nutrient-rich, biologically stable biofertilizers. This exploratory study evaluated the effects of vermicompost and its leachate, produced from sewage sludge and vineyard pruning residues, on cucumber (Cucumis sativus L.) germination and 25-day early seedling growth. Treatments included a control (peat and perlite, CNT), two vermicompost doses, 20 g kg⁻¹ and 40 g kg⁻¹ (VC_D1 and VC_D2, respectively) and a 5% (v/v) vermicompost leachate (VC_L) applied as the sole irrigation source. Foliar nutrient contents and physicochemical properties of the substrate and leachate were determined. Germination was not significantly affected (p > 0.05), but VC_D1 promoted slightly faster and more uniform seed emergence. Growth responses were dose dependent, with VC_D1 significantly enhancing shoot biomass (approximately 15% than the CNT and VC_D2) and providing a balanced foliar nutrient profile, whereas VC_D2 significantly reduced growth, promoted excessive foliar K and P, and lower Ca, Fe, and Mn contents. VC_L enhanced foliar N accumulation but did not significantly (p > 0.05) increase biomass. Both vermicompost and its leachate were pathogen-free, with metal concentrations below regulatory limits. Overall, these findings suggest that, under the tested conditions, vermicomposting these residues can generate potentially safe amendments for cucumber seedling growth, though dose optimization is essential. This exploratory approach supports residue valorization and contributes to circular economy principles and sustainable agriculture goals. Full article

Pesticides play key roles in modern agricultural activities. Optimizing pesticide deposition is essential for maximizing utilization efficiency and minimizing unintended environmental impacts. While electrostatic, hydrogen, and covalent interactions have been extensively studied to modulate pesticide adhesion to leaf surfaces, the potential of metal coordination bonding to enhance foliar deposition remains largely unexplored. In our work, abamectin-loaded PLA nanospheres coated in tannic acid (TA) (Abam@PLA) via the metal chelating ability of polyphenols (Abam@PLA-TA) were developed to improve abamectin retention on the surfaces of leaves. The chemical properties and morphological features of Abam@PLA-TA were characterized by scanning electron microscopy (SEM), transmission electron microscopy (TEM), Fourier transform infrared spectroscopy (FT-IR), and fluorescent imaging. The foliar retention of Abam@PLA-TA demonstrated that the tannic acid coating could significantly improve the adhesion ability and deposition efficiency of pesticides for crop leaves, which was mainly attributed to the hydrogen bonds between the polyphenols of TA and the polar groups of the wax layer. Moreover, Abam@PLA-TA exhibited better photostability capacity compared to the abamectin technical concentrate, which helps to protect light-sensitive pesticides from ultraviolet (UV) decomposition. This strategy opens up a simple but powerful avenue for the design of foliage adhesive systems and a new opportunity for the efficient utilization of pesticides. Full article

Metal nanoparticles are increasingly used in industry and agriculture to enhance crop yields and combat plant diseases. Their widespread application has led to exposure across all ecosystem components, including humans. However, there is a lack of a comprehensive assessment of the effect of copper nanoparticles on spearmint plants, applied in different ways (root and foliar) in a wide range of concentrations. The effect of copper nanoparticles at the concentration range of 1–100 mg/L on Mentha spicata L. plants under root exposure and foliar spraying conditions was studied during a 28-day experiment. Copper content in soil and spearmint segments was determined using inductively coupled plasma atomic emission spectroscopy, while the morphology of nanoparticles was characterized using transmission electron microscopy. Foliar spraying showed an inverse relationship between the concentration of copper in solution and root uptake. The highest copper uptake in roots of 27.51 mg/kg was attained at a nanoparticle concentration of 1 mg/L. Root exposure inhibited soil microbial activity, with copper mainly accumulating in soil (up to 950.2 mg/kg) and roots (up to 150.5 mg/kg). Both application methods stimulated pigment production and antioxidant activity, with root irrigation showing a more pronounced effect. Copper extraction efficiency varied (3–64%) depending on exposure method and concentration, raising concerns about transfer along the food chain. Health risk assessment associated with consumption of herbal infusions, prepared from copper-contaminated spearmint leaves, did not show adverse effects when copper levels in the infusion remained below 1.53 mg/L. Full article

The remediation of soils contaminated with heavy metals and radionuclides remains a significant environmental challenge. This study evaluated the phytoremediation potential of industrial hemp (Cannabis sativa L.) in soil collected from a historical evaporation dam, characterized by high levels of diverse metals, including Al, Cr, Fe, and radioactive elements (U, Th). Three treatments were applied: a control, a metal-spiked treatment (chelated with citric acid), and an NPK + spike treatment. A separate six-month greenhouse trial compared plants grown with and without NPK nutrients. Results demonstrated that the addition of a chelating agent significantly enhanced the bioavailability and subsequent uptake of key metals, including U, Se, and Pd. NPK fertilization combined with chelation resulted in the greatest plant biomass (≈4.5 g) and height (>18 cm), which correlated with higher total metal accumulation. Bioaccumulation factors (BAF > 1) were highest for B, Sr, Cd, and Bi, with values for Cd and U reaching 1.3 and 2.1, respectively. Foliar analysis revealed that leaves accumulated significantly higher metal concentrations than stems (e.g., Translocation Factor (TF) ~ 2.0 for Cd, Pb, and U), acting as the primary sink. This study concludes that hemp, particularly when assisted with chelating agents and adequate nutrition, is a highly effective candidate for the phytoremediation of multi-metal contaminated soils. The NPK + chelation strategy is the most promising for maximizing both biomass production and metal extraction efficiency. Full article

Excess Cd in soils can be accumulated in rice, presenting a serious human health risk. The effect of foliar transpiration inhibitors (TIs) on the Cd content and the endophytic bacterial community in rice plants was unclear. We evaluated the key part of the rice plant to control the Cd translocation and the profile of the endophytic bacterium structure after spraying with foliar reagents; some possible typical endophytes were induced by the TIs to inhibit the Cd translocation in the rice plant. The rice plants in three sites with different available Cd content were sprayed with foliar TIs. We assessed the Cd, N, P, K and water-soluble saccharide (WSS) in different parts of the rice plant and the endophytic bacteria community in the stem. Foliar application of TIs reduced Cd translocation factor (TF_Cd) by ~20% from the root to the grain compared with that of CK. The TI can increase the adsorptive site concentration of stem nodes from 5.10 to 6.83 mmol/g. The diversity of the endophytic bacteria community was enhanced after application of TI, and the Shannon index increased from 3.29 to 3.92. The endophytic bacterial community induced by TI showed higher potentiality on the biofilm and stress-tolerant and metal-transport functions than that of CK, respectively. The relative abundances of Burkholderiaceae and Bacterium_g_Anaeromyxobacter were significantly negatively correlated (p < 0.05), with TF_Cd and positively correlated (p < 0.05), with water-solution saccharide content, simultaneously. The TI enhanced the endophytic diversity and amount. A high abundance of special endophytic bacteria induced by TI might decrease the TF_Cd. Full article

Micronutrients play a prominent role in plant growth and development, and their bioavailability is a growing global concern. Zinc is one of the most important micronutrients in the plant life cycle, acting as a metallic cofactor for numerous biochemical reactions within plant cells. Zinc deficiency in plants leads to various physiological abnormalities, ultimately affecting nutritional quality and posing challenges to food security. Biofortification methods have been adopted by agronomists to increase Zn concentrations in crops through optimal foliar and soil applications. Changing climatic conditions and conventional agricultural practices alter edaphic factors, reducing zinc bioavailability in soils due to abrupt weather changes. Precision agriculture emphasizes need-based and site-specific technologies to address these nutritional deficiencies. Nanoscience, a multidimensional approach, reduces particle size to the nanometer (nm) scale to enhance their efficiency in precise amounts. Nanoscale forms of Zn⁺² and their broad applications across crops are gaining attention in agriculture under varied application methods. This review focuses on the significance of Zn oxide (ZnO) nanoparticles (ZnONPs) and their extensive application in crop production. We also discuss optimum dosage levels, ZnONPs synthesis, application methods, toxicity, and promising future strategies in this field. Full article

Old vineyards in production in the Pampa biome have high levels of metals, such as copper (Cu), zinc (Zn), and manganese (Mn). The high metal contents in the soil can damage the growth and development of the cover plant species that cohabit the vineyards. However, it is possible to define the critical toxicity level (CTL) of metals in soil and tissue in order to monitor and define possible strategies for reducing metal inputs and selecting more tolerant species. This study aimed to define the CTL of Cu, Zn, and Mn in the soil and plant tissue of plants present between the rows of vineyards with different cultivation histories in the Pampa biome in South America. For this purpose, soil and plant tissue samples were collected in a native field area (NF), without agricultural cultivation and in two vineyards, vineyard 1 (V1) and vineyard 2 (V2), both with a history of fungicide application. To define the CTL, the foliar concentrations and soil contents of Cu, Zn, and Mn were correlated with the dry mass production of the shoot. The CTLs for Cu, Zn, and Mn in the soil were set at 15, 3.0, and 35 mg kg⁻¹, respectively. In the tissue, CTLs for Cu, Zn, and Mn were estimated at 75, 77, and 380 mg kg⁻¹, respectively. The contents of Cu, Mn, and Zn in the soil of the vineyards are above the CTL. The concentrations of the metals in the tissue varied, with samples above the CTL for Cu and Zn in the vineyards. The values of Cu, Zn, and Mn in NF are below the CTL in soil and tissue. The high contents of Cu, Zn, and Mn in the soil and tissue limited the dry mass production of the plants between the rows of vineyards. Full article

Among numerous global problems, one of the most significant is air pollution. In this paper, unwashed (U) and water-washed (W) needles of two conifers—European larch and Douglas fir—were used to assess their capacity for the retention and accumulation of heavy metals. The needle samples were used to represent the atmospheric deposition of heavy metals located on the surface of the needles. The sampled European larch and Douglas fir plantations were situated at three locations in Serbia: a least polluted (Kučevo), a moderately polluted (Avala), and a very polluted (Lazarevac) site. The content of five heavy metals (Ni, Cu, Co, Cd, Pb) was investigated in the study. The concentration of cadmium (Cd) was higher in the European larch needles compared to Douglas fir, while the differences in the content of the other heavy metals between the species studied were insignificant. For both species, the following trend applied with respect to the heavy metal content in their needles: Ni ˃ Cu ˃ Co ˃ Pb ˃ Cd. Based on the results obtained, we deduced that the concentrations of all investigated heavy metals at all three locations for both species were within the allowed limits, except for nickel (Ni) content, which was over the predicted limit values for both species in the highly polluted area (Lazarevac). A PCA (principal component analysis) undertaken suggests that European larch has a greater ability to accumulate Co than Douglas fir on sites contaminated with heavy metals. The predictive foliar metal accumulation index (MAI) value was slightly higher in Douglas fir (4.14) than in European larch (3.76); therefore, the results suggest that this species would be a good planting choice, particularly in urban and industrial environments. Full article

Various metal-based nanomaterials have been the focus of research regarding their use in controlling pests and diseases and in improving crop yield and quality. In this study, we synthesized via a solvothermal procedure pegylated zinc-doped ferrite (ZnFer) NPs and characterized their physicochemical properties by X-ray diffraction (XRD), vibrating sample magnetometry (VSM), thermogravimetric analysis (TGA), FT-IR and UV–Vis spectroscopies, as well as transmission electron microscopy (TEM). Subsequently, their impact on tomato photosynthetic efficiency was evaluated by using chlorophyll a fluorescence imaging analysis to estimate the light energy use efficiency of photosystem II (PSII), 30, 60, and 180 min after foliar spray of tomato plants with distilled water (control plants) or 15 mg L⁻¹ and 30 mg L⁻¹ ZnFer NPs. The PSII responses of tomato leaves to foliar spray with ZnFer NPs showed time- and dose-dependent biphasic hormetic responses, characterized by a short-time inhibitory effect by the low dose and stimulatory effect by the high dose, while at a longer exposure period, the reverse phenomenon was recorded by the low and high doses. An inhibitory effect on PSII function was observed after more than ~120 min exposure to both ZnFer NPs concentrations, implying a negative effect on PSII photochemistry. We may conclude that the synthesized ZnFer NPs, despite their ability to induce hormesis of PSII photochemistry, have a negative impact on photosynthetic function. Full article

Modern potato varieties from high-input, conventional farming-focused breeding programs produce substantially (up to 45%) lower yields when grown in organic production systems, and this was shown to be primarily due to less efficient fertilization and late blight (Phytophthora infestans) control methods being used in organic farming. It has been hypothesized that the breeding of potato varieties suitable for the organic/low-input sector should (i) focus on increasing nutrient (especially N) use efficiency, (ii) introduce durable late blight resistance, and (iii) be based on selection under low-input conditions. To test this hypothesis, we used an existing long-term factorial field experiment (the NEFG trials) to assess the effect of crop management practices (rotation design, fertilization regime, and crop protection methods) used in conventional and organic farming systems on crop health, tuber yield, and mineral composition parameters in two potato varieties, Santé and Sarpo mira, that were developed in breeding programs for high and low-input farming systems, respectively. Results showed that, compared to Santé, the variety Sarpo mira was more resistant to foliar and tuber blight but more susceptible to potato scab (Streptomyces scabies) and produced higher yields and tubers with higher concentrations of nutritionally desirable mineral nutrients but lower concentrations of Cd. The study also found that, compared to the Cu-fungicides permitted for late blight control in organic production, application of synthetic chemical fungicides permitted and widely used in conventional production resulted in significantly lower late blight severity in Sante but not in Sarpo mira. Results from both ANOVA and redundancy analysis (RDA) indicate that the effects of climatic (precipitation, radiation, and temperature) and agronomic (fertilization and crop protection) explanatory variables on crop health and yield differed considerably between the two varieties. Specifically, the RDA identified crop protection as a significant driver for Santé but not Sarpo mira, while precipitation was the strongest driver for crop health and yield for Sarpo mira but not Santé. In contrast, the effect of climatic and agronomic drivers on tuber mineral and toxic metal concentrations in the two varieties was found to be similar. Our results support the hypothesis that selection of potato varieties under low agrochemical input conditions can deliver varieties that combine (i) late blight resistance/tolerance, (ii) nutrient use efficiency, and (iii) yield potential in organic farming systems. Full article

Plant small molecules, such as nitric oxide (NO) and melatonin (MN) as natural and human health-friendly compounds, play important roles in the mitigation of abiotic stresses in plants. Heavy metals such as chromium (Cr) are hazardous for the survival of ornamentals, especially edible flowers. This study evaluated the effects of NO (50 µM; sourced as sodium nitroprusside) and MN (50 µM) applied two times through foliar spraying at 1-week intervals on alleviating Cr (120 µM; K₂Cr₂O₇)-induced oxidative stress in edible flowers of Calendula officinalis cv. Orange King. Cr stress decreased plant dry mass, leaf SPAD values, net photosynthetic rates, and the maximum photochemical quantum yield (F_v/F_m), and increased the oxidative stress markers. The individual application of NO or MN significantly mitigated the adverse effects, and the combined application of NO and MN synergistically enhanced plant tolerance to Cr stress, including increased activities of antioxidant enzymes in plants and concentrations of carbohydrate, ascorbic acid, sugar, total protein, as well as ash contents of edible flowers. The co-application also significantly elevated the concentrations of total phenolics, flavonoids, free reducing power, antioxidant capacity DPPH, and total carotenoids in Cr-treated plants compared with those in Cr-stressed plants. Additionally, the essential oil contents in flowers increased in response to the signaling molecule treatment under Cr stress. Compared with individual applications, the co-application of NO and MN had more significant effects. Our results indicate that the combination of signaling molecules, such as MN and NO, can not only increase the biomass of edible calendula plants but also improve flower quality for use as a novel food. Full article

Nano-priming is a relatively new seed treatment technique using metal and metal oxide nanoparticles (NPs), and such application of NPs may support the plants’ immunity. Recently we have shown that the that biologically synthesized silver nanoparticles (bio-AgNPs) used as short-term foliar treatment protect pea seedlings against D. pinodes and F. avenaceum. In the present study, the protection of peas against both fungal pathogens via seed priming with bio-AgNPs was analyzed. Moreover, the changes in the polar metabolic profiles of the seedlings caused by priming and infection were also compared. Seed priming with bio-AgNPs at concentrations of 50 and 100 mg/L considerably reduced the symptoms and infection levels of both pathogens by over 70% and 90% for F. avenaceum and D. pinodes, respectively. Pathogens infection and nano-priming affected the metabolic profile of pea seedlings. The major changes in the primary metabolism were observed among carbohydrates and amino acids. In turn, this may result in changes in the expression and accumulation of secondary metabolites. Therefore, further investigation of the effect of nano-priming should focus on the changes in the secondary metabolism. Full article

Exogenous application of sodium nitroprusside (SNP) has previously been reported to trigger plant tolerance against a variety of environmental stresses. The present study was planned to investigate the possible role/s of exogenously applied SNP (50 or 100 μM) in alleviating cadmium (Cd)-induced effects on physio-biochemical processes, yield attributes, and grain quality traits of three fragrant rice cultivars, viz., Meixiangzhan-2 (MXZ), Guixiangzhan (GXZ), and Xiangyaxiangzhan (XYXZ) under 50 mg Cd kg⁻¹ of soil. The results revealed that foliar spray of SNP (50 or 100 μM) on Cd-stressed rice plants reduced oxidative stress (lower hydrogen peroxide (H₂O₂), malondialdehyde (MDA), and electrolyte leakage (EL)) and improved the photosynthetic apparatus through higher chlorophyll contents, gas exchange attributes, and intact chloroplast configurations, and reduced Cd concentration in the leaves and grains of aromatic rice cultivars. The reduced levels of cellular ROS, MDA, and EL were related to the endogenous NO-mediated improvement in the activity of anti-oxidative enzymes and those involved during the ascorbate–glutathione cycle. However, among the different SNP levels, the foliar spraying of 50 μM of SNP was recorded to be the best treatment for fragrant rice growth, which increased grain yield by 42.06%, 46.03%, and 31.21%, and the quality trait of 2-acetyl-1-pyrroline (2-AP) content by 43.12%, 55.84%, and 35.72% in MXZ, GXZ, and XYXZ respectively, suggesting that GXZ is more responsive to SNP than MXZ and XYXZ fragrant rice cultivars. Collectively, our results deduced that cultivating the GXZ fragrant rice cultivar along with foliar application of 50 μM of SNP could sustain the grain yield and quality features of aromatic rice cultivation in heavy metal (especially Cd)-polluted soils. Full article

Using contaminated land to grow lignocellulosic crops can deliver biomass and, in the long term, improve soil quality. Biostimulants and microorganisms are nowadays an innovative approach to define appropriate phytomanagement strategies to promote plant growth and metal uptake. This study evaluated biostimulants and mycorrhizae application on biomass production and phytoextraction potential of four lignocellulosic crops grown under two metal-contaminated soils. Two greenhouse pot trials were setup to evaluate two annual species (sorghum, hemp) in Italy and two perennial ones (miscanthus, switchgrass) in China, under mycorrhizae (M), root (B2) and foliar (B1) biostimulants treatments, based on humic substances and protein hydrolysates, respectively, applied both alone and in combination (MB1, MB2). MB2 increased the shoot dry weight (DW) yield in hemp (1.9 times more), sorghum (3.6 times more) and miscanthus (tripled) with additional positive effects on sorghum and miscanthus Zn and Cd accumulation, respectively, but no effects on hemp metal accumulation. No treatment promoted switchgrass shoot DW, but M enhanced Cd and Cr shoot concentrations (+84%, 1.6 times more, respectively) and the phytoextraction efficiency. Root biostimulants and mycorrhizae were demonstrated to be more efficient inputs than foliar biostimulants to enhance plant development and productivity in order to design effective phytomanagement strategies in metal-contaminated soil. Full article

Several researchers recognize the importance of plants as effective tools for environmental biomonitoring. The black poplar (Populus nigra L.) often emerges as a useful bioindicator of air quality in urban environments, where this tree species is widely employed for urban areas. Here, we used ICP-MS analysis to assess the presence and concentration of trace elements, with a special focus on heavy metals (HMs), in black poplar leaves and soil samples from three urbanized sites showing varying degrees of environmental quality. Specifically, the foliar concentrations of Zn (173.3 ppm), Cd (0.7 ppm), Co (1.1 ppm) and As (0.2 ppm) exceeded reference values for unpolluted sites, indicating potential environmental hazards. Additionally, we correlated the foliar concentrations of HMs with those quantified in soil and with air quality data provided by the regional air quality-monitoring network. Subsequently, we estimated the values of foliar fluctuating asymmetry, and evaluated their relationships with HM concentrations in both leaves and soil. Our results suggest that element concentrations in black poplar leaves are related to soil contamination and atmospheric quality, and the extent depends on the proximity to relevant pollution sources. Furthermore, the study species showed a pronounced accumulation capacity for some HMs (i.e., Zn, Cd) commonly found in particulate matter. The extent of foliar fluctuating asymmetry is related to atmospheric quality and HM soil concentration, possibly because of the growth anomalies induced by this kind of environmental contamination. Overall, our data indicate the study species can supply an effective biomonitoring service in urbanized contexts, offering valuable insights into the occurrence and biological implications of heavy metal contamination. Full article