Farmland birds are declining across Europe and North America and the research of factors behind is the subject of extensive researches. Agricultural intensification is now recognized as a major factor governing the loss of biodiversity with strong evidence that pesticides induced direct bird mortality at a high dose. However, less attention has been given to the long-term effects of chronic exposure to low dose of pesticides. Here, we used an experimental procedure in which grey partridges were fed with untreated grains obtained from either organic (no pesticide) or conventional agriculture (with pesticide) for 26 weeks, thus strictly mimicking wild birds foraging on fields. We then examined a suite of life-history traits (ecophysiological and behavioural) that may ultimately, influence population dynamics. We show for the first time that ingesting low pesticide doses over a long period has long-term consequences on several major physiological pathways without inducing differential mortality. Compared to control partridges, birds exposed to chronic doses i) had less developed carotenoid-based ornaments due to lower concentrations of plasmatic carotenoids, ii) had higher activated immune system, iii) showed signs of physiological stress inducing a higher intestinal parasitic load, iv) had higher behavioural activity and body condition and v) showed lower breeding investment. Our results are consistent with a hormetic effect, in which exposure to a low dose of a chemical agent may induce a positive response, but our results also indicate that breeding adults may show impaired fitness traits bearing population consequences through reduced breeding investment or productivity. Given the current scale of use of pesticides in agrosystems, we suggest that such shifts in life-history traits may have a negative long-term impact on wild bird populations across agrosystems. We stress that long-term effects should no longer be ignored in pesticide risk assessment, where currently, only short-term effects are taken into account.

An emerging stress of pesticides in plant and soil is closely watched as it affects crop antioxidant systems, nutritional quality, and flavor. Although selenium (Se) can enhance the resistance of plants, the protective mechanism of nanoselenium is still not known under the long-term pesticide stress in tea trees. In this study, we investigated the potential effects of foliar application of nanoselenium for a two-year field experiment on tea plants under pesticide-induced oxidative stress. Compared to control, nano-Se (10 mg/L) markedly enhanced the protein, soluble sugar, carotenoid, tea polyphenols, and catechins contents. High levels of theanine, glutamic acid, proline, and arginine were found to be induced most likely by adjusting the GS-GOGAT cycle. Se-supplementation may promote tea leaves’ secondary metabolism, thus increasing the accumulation of total phenols and flavonoids (apigenin, kaempferol, quercetin, myricetin, and rutin). It also minimized the accumulation of malondialdehyde, hydrogen peroxide, and superoxide anion by activating the antioxidants enzymes including in the AsA-GSH cycle. Selenium-rich tea also showed better fragrance and flavor. In summary, nano-Se can ameliorate the nutrients quality and abiotic stresses resistance of crops.

Currently, there is a lack of information about the influence of foliar-applied nanoplastics on crop growth and nutritional quality. To fill the knowledge gap, soil-grown lettuces (Lactuca sativa L.) were foliar-exposed to polystyrene nanoplastics (PSNPs) at 0, 0.1 and 1 mg/L for one month. Foliar exposure to PSNPs significantly decreased the dry weight, height, and leaf area of lettuce by 14.3%–27.3%, 24.2%–27.3%, and 12.7%–19.2%, respectively, compared with the control. Similarly, plant pigment content (chlorophyll a, b and carotenoid) was considerably reduced (9.1%, 8.7%, 12.5%) at 1 mg/L PSNPs. However, the significant increase in electrolyte leakage rate (18.6%–25.5%) and the decrease in total antioxidant capacity (12.4%–26%) were the key indicators of oxidative stress in lettuce leaves, demonstrating the phytotoxicity of PSNPs by foliar exposure. In addition, the remarkable reduction in micronutrients and essential amino acids demonstrated a decrease in nutritional quality of lettuce caused by PSNPs. Besides, SEM and TEM analysis indicated the possible absorption of PSNPs through leaves stoma and the translocation downwards to plant roots. This study provides new information about the interaction of airborne NPs with plants. It also warns against atmospheric NPs pollution that the adverse effects of airborne NPs on crop production and food quality should be assessed as a matter of urgency.

In the present study, a hydroponic experiment was performed to evaluate the effect of exogenous silicon (Si) and methyl jasmonate (MeJA) on the mitigation of Cd toxicity in tomato seedlings. The results revealed that Cd-stressed plants exhibited growth inhibition, increased lipid peroxidation, and impaired photosynthetic pigment accumulation. However, Si and MeJA applied alone or in combination significantly ameliorated the above-mentioned adverse effects induced by Cd. Among all treatments, Cd+Si+MeJA treatment elevated the dry mass of roots, stems, and leaves by 317.39%, 110.85%, and 119.71%, respectively. The chlorophyll a, chlorophyll b, and carotenoid contents in Cd+Si+MeJA-treated group were dramatically elevated (p < 0.05). Meanwhile, the malondialdehyde content in roots and shoots were reduced by 32.24% and 69.94%, respectively. The Si and MeJA applied separately or in combination also resulted in a prominent decrease of Cd influxes in tomato roots; therefore, a reduction of Cd content in tomato tissues were detected, and the Cd concentration in tomato roots were decreased by 27.19%, 25.18%, and 17.51% in Cd+Si, Cd+MeJA and Cd+Si+MeJA-treated plants, respectively. Moreover, in Cd+Si+MeJA-treated group, the percentage of Cd in cell wall fraction was enhanced while that in organelle fraction was decreased as compared with Cd-stressed plants. Collectively, our findings indicated that Si and MeJA application provide a beneficial role in enhancing Cd tolerance and reducing Cd uptake in tomato plants.

In this research, the sorption behavior (kinetic, isotherm, and thermodynamic modeling) of heavy metals (Cu (II) and Fe (II)) and pigments (carotenoid and chlorophyll) onto activated bentonite clay was investigated for soybean oil under industrial (IBM) and ultrasonic bleaching method (UBM). A nonlinear fitting approach was used to determine the best-fit isotherm and kinetic models by two statistical criteria including the coefficient of determination (R²) and chi-square (χ²). The adsorption of metal ions and pigments onto activated bentonite clay under UBM was quite well by the pseudo-first-order model. In both bleaching methods, the equilibrium adsorption data follows the Toth isotherm model, presenting the sorption occurrence tends to be on a heterogeneous surface. The results indicated that the adsorption thermodynamics was endothermic in nature and the process was spontaneous between 35 and 65 °C.

Approximately 6% of the world’s total land area and 20% of the irrigated land are affected by salt stress. Egypt is one such country affected by salt-stress problems. This paper focuses on the role of isolated bacteria, such as Bacillus subtilis and Pseudomonas fluorescens, in alleviating the harmful effects of salt stress. The results show that the irrigation of plants with different concentrations of saline water (0, 75, and 150 mM NaCl) leads to significantly decreased growth criteria, photosynthetic pigments (i.e., chl a, chl b, and carotenoids), and membrane stability index (MSI) values. Moreover, malondialdehyde (MDA), glutathione content, endogenous proline, the antioxidant defense system, 1-aminocyclopropane-1-carboxylic acid (ACC) content, ACC synthase (ACS), ACC oxidase (ACO), and Na⁺ content were significantly increased under NaCl-stress exposure. On the contrary, treatment with endophytic bacteria significantly increased the resistance of pea plants to salt stress by increasing the enzymatic antioxidant defenses (i.e., superoxide dismutase, catalase, peroxidase, and glutathione reductase), non-enzymatic antioxidant defenses (i.e., glutathione), osmolyte substances such as proline, and antioxidant enzyme gene expression. As a result, endophytic bacteria’s use was significantly higher compared to control values for indole-3-acetic acid (IAA), gibberellic acid GA₃, MSI, and photosynthetic pigments. The use of endophytic bacteria significantly decreased Na⁺ accumulation while, at the same time, promoting K⁺ uptake. In conclusion, the induction of endophytic bacterium-induced salt tolerance in pea plants depends primarily on the effect of endophytic bacteria on osmoregulation, the antioxidant capacity, and ion uptake adjustment by limiting the uptake of Na⁺ and, alternatively, increasing the accumulation of K⁺ in plant tissue.

The conservation and management of rain and water in a city environment are a crucial aspect of sustainability. Sponge cities are a solution for the remediation of excessive water consumption, high pollution, and rainstorm waterlogging in urban areas. Perennial ryegrass (Lolium perenne L.) is a common species and promising bioremediation plant for the construction of sponge cities. It could be useful to purify high nitrogen and phosphorus content in wastewater runoff, but its response to high total nitrogen (TN) and total phosphorus (TP) levels has not been studied. The present study aimed to evaluate the effects of high TN + TP level on seed germination, plant growth, antioxidant response, and assimilation rate of N and P in perennial ryegrass. Compared with the control, treatments with 20 mg/L N + 4 mg/L P (20N4P) significantly decreased germination potential at day 3, but the germination rate at day 10 was similar between all treatments and the control, suggesting that a high TN + TP concentration might delay germination, but not prevent it. Treatment with 20N4P also induced significant withering and decreased shoot length, root length, and dry shoot weight of ryegrass seedlings, compared with the control. Treatments with 80N16P significantly decreased levels of chlorophyll a (Chl-a) and chlorophyll b (Chl-b), demonstrating inhibition of photosynthesis. Compared with the control, treatment with 40N8P increased the carotenoid (Car), malondialdehyde (MDA), and glutathione (GSH) content, which might alleviate oxidative stress induced by high TN + TP concentration. Moreover, high levels of TN + TP (160N32P and 320N64P) significantly reduced the removal capacity of N and P by plants. Overall, the present results provide a theoretical foundation for the development of ryegrass for bioremediation of wastewater during construction of sponge cities.

As a result of its high production, bisphenol A (BPA) has become ubiquitous in aquatic and terrestrial habitats. In this study, we investigated the toxicity of BPA at 10 mg L⁻¹ on Lemna minor after 7 days of exposure under controlled conditions according to ISO 20079. BPA statistically reduced the total frond number and frond area, while frond number per colony was significantly elevated in BPA-treated group. However, no change was recorded in root number, while root length was significantly reduced by BPA. BPA also decreased the content of Chl a, Chl b, Chl a + b, and carotenoid by 36%, 44%, 38%, and 32%, respectively, versus the control leading to a decrease in the quantum yield of photosystem II. In addition, non-photochemical quenching (NPQ) values were 2.4- and 4.5-fold higher in light than in dark conditions for control and BPA-treated plants, respectively. Thus, there is a significant activation (61.8%; p<0.01) of PSII photoprotection mechanism (NPQ) in BPA-treated plants compared to control but without removing the negative effect of BPA on PSII. The total amount of soluble sugars was reduced by 40% compared to control, and starch accumulation was mainly observed in fronds exposed to BPA. Even if the response patterns of Lemna minor based on fresh and dry weight measurements were less sensitive in our experiment conditions, further studies should be addressed since BPA represents a threat to the dynamic equilibrium governing aquatic ecosystems.

Applications of nanoparticles and plants for efficient restoration of heavy metal-polluted water and soil are an emerging approach and need to be explored. Hydroponic study was performed to find the role of zinc oxide nanoparticles (ZnO NPs) in plant growth, antioxidative response, and lead (Pb) accumulation in Persicaria hydropiper. Seedlings were grown in Pb-polluted media amended with 5, 10, 15, and 20 mg L⁻¹ ZnO NPs. Inductively coupled plasma spectroscopy (ICP) was used for Pb analysis in plant tissues. Pb significantly inhibited seedling growth, and ZnO NPs alleviated Pb-induced stress by promoting plant growth, and improved chlorophyll and carotenoid contents. Oxidative stress ameliorated in ZnO NPs exposed seedlings through enhanced production of free proline, phenolics, flavonoids, and activation of antioxidative enzymes. Pb accumulation boosted in ZnO NP treatments, and highly significant increase in Pb accumulation in roots (255.60±4.80 mg kg⁻¹), stem (124.07±2.84 mg kg⁻¹), and leaves (92.00±3.22 mg kg⁻¹) was observed in T3 (15 mg L⁻¹ ZnO NPs) for P. hydropiper. Contrarily, ZnO NPs at 20 mg L⁻¹ dose suppressed plant growth, Pb accumulation, secondary metabolites, and antioxidative enzyme activities. Moreover, positive correlation was found in Pb accumulation with free proline and secondary metabolite contents in plant tissues. These results suggest that ZnO NPs at optimum concentration may augment efficacy of plants to remove heavy metal from polluted water through nanophytoremediation.

A pot experiment was conducted to evaluate the phytoremediation efficacies of seven weed plant species, viz., Bidens pilosa L., Chenopodium album L., Malvastrum coromandelianum L., Garcke, Oxalis corniculata L., Parthenium hysterophorus L. (an invasive species), Polypogon monspeliensis L., and Rumex dentatus L., against heavy metals like chromium (Cr) and Nickel (Ni). These metals were administered in dose ranges from 10 to 40 mg CrNO₃ and 10 to 50 mg NiNO₃ kg–¹ soil. Biochemical parameters like total chlorophyll, carotenoids, protein, and proline contents were measured against metal stress. Uptake parameters, viz., bioconcentration factor (BCF), bioaccumulation coefficient (BAC), and translocation factor (TF), were also evaluated. Remediation potential of experimental plants was judged based on tolerance index (TI). All plants, when treated with Ni₁₀–₂₀ and Cr₁₀ enhanced total chlorophyll and carotenoid contents. Increase in contamination and enrichment ratio caused a toxic response to plants up to some extent. Ni and Cr stress decreased the protein content and increased proline content in a concentration-dependent manner. Plant species invariably showed high TI at the lowest dose and low TI at higher doses of both heavy metals. A significant increase in Cr and Ni accumulation, coupled with a high bioaccumulation coefficient, in roots and shoots of all seven species was observed as a response to Cr and Ni stress.