Search Results (1,262)

The sustainable management of biowaste, mainly food and pruning waste, is currently a challenge due to the increase in its production. The CaMPuSTAJE program, which has been implemented on the campus of the Public University of Navarre (UPNA) since 2019, is an excellent example of how the institution is addressing its strategic interests in sustainable waste management. The principal aim of this program is to manage the biowastes generated by the campus canteens through a simple community composting facility, involving UPNA students and graduates. This program aims to promote experiential learning and applied research in sustainability and circular economy, managing their own waste in a circular and local way. Thus, four composting sets of the CaMPuSTAJE program were evaluated by monitoring the process and the main chemical properties of the composting samples. Also, final composts were fully characterized to ensure the process reproducibility and efficiency and the absence of any hazard in the end-products. The final composts showed a significant agronomic quality, had low content of potentially toxic elements, and were free from phytotoxicity, thus being able to be reintroduced as an organic amendment at the university campus itself. Full article

Composting is an environmentally friendly treatment technology that recycles and sanitizes organic solid waste. This study aimed to assess the evolution of nutrients, maturity, and microbial communities during the composting of different plant-derived wastes. The composting process was conducted over 49 days using three types of plant-derived waste: wheat bran (WB), peanut straw (PS), and poplar leaf litter (PL). This process was examined through physical, chemical, and biological parameters. The results revealed that after 49 days of composting, the three groups experienced significant changes. They were odorless, were insect-free, exhibited a dark brown color, had an alkaline pH value, and had an electrical conductivity (EC) value of less than 4 mS/cm. These characteristics indicated that they had reached maturity. Nutrient content was the most significant factor influencing the degree of humification of the different composting materials, while changes in microbial community diversity were the key driving factors. Significantly, the compost PS, derived from peanut straw, entered the thermophilic phase first, and by the end of composting, it had the lowest organic matter (OM) loss rate (17.4%), with increases in total nitrogen (TN), total phosphorus (TP), and total potassium (TK) in the order of PS > PL > WB. The increase in humus carbon (HSC) content and the humic acid/fulvic acid (HA/FA) ratio followed the order PS > WB > PL. FTIR spectra indicated that PS had greater aromatic characteristics compared to the other samples. The abundance and diversity of bacterial and fungal communities in the compost increased significantly, accompanied by more complex community structures. Crucially, there were no phytotoxic effects in any of the three composting treatments, and the compost PS boasted a high germination index (GI) of 94.79%, with the lowest heavy metal contents. The findings indicate that the compost PS has the highest potential for resource utilization and is suitable for agricultural applications. Our results demonstrate that composting technology for plant-derived waste has the potential to enhance soil fertility and provide a reference for the composting treatment and resource utilization of other plant-derived waste. Full article

The residues of the herbicides aminopyralid and iodosulfuron-methyl-sodium are phytotoxic to rotational crops. Their behaviour therefore needs to be studied under different agronomic practises and climatic conditions. The objective of this work was to use controlled laboratory conditions to study the effect of the following: (i) the application of green compost (GC) to agricultural soil, (ii) herbicide dose, (iii) soil moisture, and (iv) soil microbial activity on the degradation rate of aminopyralid and iodosulfuron-methyl-sodium. Moreover, the formation of two iodosulfuron-methyl-sodium metabolites (metsulfuron-methyl and 2-amino-4-methyl-4-methoxy methyl-triazine) and the dissipation mechanism of labelled ¹⁴C-iodosulfuron-methyl-sodium under the same conditions were also studied. Aminopyralid and iodosulfuron-methyl showed slower degradation and half-life values (DT₅₀) that were up to 4.6 and 1.4 times higher, respectively, in soil amended with GC, as the higher organic carbon (OC) content of this soil increased herbicide adsorption. The DT₅₀ values were up to 2.6 and 1.9 times higher for aminopyralid and iodosulfuron-methyl sodium, respectively, in soils treated with the double herbicide dose compared to soils treated with the agronomic dose. The DT₅₀ values for aminopyralid were up to 2.3 times higher in soils with moisture equal to 25% (H25%) of their water-holding capacity (WHC) than in soils with H50%. However, the DT₅₀ values for iodosulfuron-methyl-sodium were slightly lower in soils with H25% than in soils with H50%, due to the formation of bound residues. A biodegradation process significantly contributes to the dissipation of both herbicides. Higher amounts of metabolite metsulfuron-methyl were formed in the GC-amended soil in all cases. The percentages of ¹⁴C extractable in soils treated with both doses of herbicide under H25% were slightly higher than in soils under higher soil moisture (H50%) over time, due to the slower degradation of ¹⁴C-(iodosulfuron-methyl+metabolites). The higher persistence of the herbicides and their metabolites when the doses were applied at a high rate in soil amended with GC and under low moisture content may have negative consequences for the rotational crop. In the case of adverse conditions leading to the persistence of herbicides in the soil during the primary crop, the intervals for crop rotation should be increased. Full article

Contamination of aquatic and terrestrial ecosystems with microplastics (MPs) and nanoplastics (NPs) has raised significant global concerns. While most studies have focused on aquatic contamination, knowledge concerning the effect of MPs and NPs in biosolids on agricultural field crops remains limited, as is the range of polymer types tested. In this study, polyethylene nanoplastics (HDPE-NPs, <500 nm diameter) were produced in the lab, and their effect on tomato plants (Solanum lycopersicum L.) was studied at different growth stages. Physical and chemical characterizations of the HDPE-NPs were performed. Compared to the control group, the presence of 2.8 mg/kg HDPE-NPs in soil increased tomato leaf greenness (p < 0.05), while the presence of 0.5 mg/kg HDPE-NPs in the soil lowered water use efficiency (WUE, p < 0.05) of the plants in the early vegetative stage. Soil CO₂ emissions were significantly lower under both the 0.5 mg/kg (p < 0.05) and 2.8 mg/kg HDPE-NPs treatments (p < 0.05). At the early germination stage, HDPE-NPs in the soil resulted in stunted seedlings (p < 0.001). Moreover, the average fruit weight and number of fruits borne by mature plants were adversely affected, possibly because of potential alterations in soil nitrogen content and associated plant uptake pathways. A pattern of hormetic dose response was observed for some measured parameters, including leaf greenness, plant WUE, and soil CO₂ emissions, although the underlying mechanisms remain unclear. Overall, the range between 1 and 5 mg/kg concentration of HDPE-NPs in soil was found to have the greatest impact on tomato plants, while other factors may contribute to the observed effects. Full article

It is well known that modern agriculture would not be able to meet the current demand for food without the help of pesticides. However, conventional pesticides have been proven to be extremely harmful to the environment, to the species they are applied to, and, ultimately, to humans. As a result, bio-pesticides have been introduced in recent years and include natural substances that control pests, such as biochemical pesticides, microorganisms used as pest control agents (microbial pesticides), and pesticide substances produced by plants containing added genetic material, known as plant-incorporated protectants (PIPs). Although these are natural products, their widespread use has led to an increased presence in the environment, raising concerns regarding their potential impact on both the environment and human health. The aim of our study was to determine the phyto- and cytogenotoxicity caused by two insecticides, both certified for use in ecological agriculture: one biochemical (BCP) and the other microbial (MP), which were applied in three concentrations (the maximum recommended concentration by the manufacturers (MRFC), 1.5X MRFC, and 2X MRFC) to the meristematic root tissues of Allium cepa. The results were compared to a negative control (tap water) and a positive control (a chemical pesticide (CP) containing mainly Deltamethrin). Phytotoxic and cytogenotoxic effects were analyzed at two time intervals (24 and 48 h) by measuring root length, growth percentage, root growth inhibition percentage (phytotoxicity tests), and micronuclei frequency and chromosome aberrations (anaphase bridges, chromosomal fragments, anaphase delays, sticky chromosomes, laggard/vagrant chromosomes) (cytogenotoxicity analyses), respectively. The tests conducted in this study showed that the microbial insecticide provides greater safety when applied, even at higher doses than those recommended by the manufacturers, compared with the biochemical insecticide, whose effects are similar to those induced by the chemical pesticide containing Deltamethrin. However, the results suggest that both insecticides have clastogenic and aneugenic effects, highlighting the need for prior testing of any type of pesticide before large-scale use, especially since the results of the A. cepa tests showed high sensitivity and good correlation when compared to other test systems, e.g., mammals. Full article

Cheese production generates a large amount of liquid waste called cheese whey (CW). The management of CW is not optimized in Ecuador since a large proportion of it is discharged into the soil or effluents, causing significant environmental impacts. For this reason, the co-composting of whey with solid organic wastes can be a suitable method for its treatment for small companies generating this liquid waste due to its effectiveness and low cost. In this study, we analyzed 10 CW samples from different small companies in the Mocha canton (Tungurahua, Ecuador) to determine specific physicochemical and chemical parameters. Subsequently, a waste pile was formed with crop residues (corn and beans) and cow manure, which was composted using the turned pile composting system. Throughout the composting process, the temperature of the pile was controlled, its moisture was maintained between 40 and 60% by adding whey, and several physicochemical, chemical, and biological properties were determined. The results showed that the CW presented a high organic load, notable macronutrient content, and low heavy metal concentrations, all of which are beneficial for its co-composting with other organic solid wastes. The only limiting factors involved in using large amounts of whey in the composting process were the low pH values of the acid CW and the high concentrations of salts. It was also observed that co-composting CW with agro-livestock wastes was a viable strategy to treat these wastes and produce compost with stabilized and humified organic matter and remarkable agricultural value. Full article

Efforts to develop weed management alternatives are urgently required due to various challenges, such as declining crop yields, rising production costs, and the growing prevalence of herbicide-resistant weed species. Chalcones occur in nature and have phytotoxic potential and concise synthesis; additionally, they are multifunctional, with diverse biomolecular targets and a broad spectrum of biological activities. This study sought to assess the herbicidal potential of 3?-hydroxychalcones against weed species under laboratory conditions. Their effects were investigated using germination bioassays, early growth measurements, and the seedling vigor index, all prepared with a concentration of 1 × 10^?3 mol L^?1 3?-hydroxychalcones. 3?-Hydroxy-4-pyridyl-chalcone caused the greatest inhibition (81%) of the seedling length in Urochloa decumbens. Other 3?-hydroxychalcones also caused large initial growth reductions, such as 3?-hydroxy-4-pyridyl-chalcone (75%) and 3?-hydroxy-4-nitrochalcone (68%) in Digitaria insularis and 3?-hydroxy-4-bromochalcone (73%) in Raphanus raphanistrum. The greatest reduction in the seedling vigor index was 81% in D. insularis treated with the 3?-hydroxy-4-bromochalcone. The same 3?-hydroxychalcone caused an 80% reduction in Amaranthus viridis. In conclusion, 3?-hydroxychalcones exhibit herbicidal activity, suggesting they could serve as a solution for future weed management strategies. Full article

Citric acid (CA), a naturally occurring compound in fruits, mainly citrus, has gained attention for its eco-friendly potential in wood modification. Through esterification, citric acid reacts with wood polymers to form bonds that improve adhesion, dimensional stability, and durability while reducing moisture absorption and susceptibility to decay. This study evaluated the efficacy of CA as an eco-friendly wood treatment. Wood samples were treated with solutions at varying concentrations (5%, 10%, and 15%) and assessed for dimensional stability, mechanical properties, biological resistance, and ecotoxicity. CA treatments significantly improved dimensional stability, with higher concentrations yielding greater weight percent gain (WPG) and anti-swelling efficiency (ASE). Biological tests demonstrated exceptional termite resistance, with no survival and minimal mass loss in treated samples at higher concentrations. Similarly, fungal resistance improved, as citric acid inhibited fungal growth. Ecotoxicity tests showed relatively low phytotoxicity, with some decrease in germination indices (GI) at higher CA concentrations. These findings highlight CA as a sustainable wood treatment for enhanced durability and biodegradation resistance in construction and outdoor applications. Full article

Maize hybrids exhibit varying levels of tolerance to the herbicide nicosulfuron, influenced by the environment, plant developmental stage, and herbicide rate. The objective of this study was to determine the sensitivity of maize hybrids to nicosulfuron through biochemical markers. Eight hybrids were treated with 120 g ha⁻¹ of nicosulfuron at the V2 and V6 growth stages in a greenhouse experiment. The plants were collected at one day after the application of the herbicide to determine the contents of nicosulfuron, aminobutyric and quinic acids and valine, leucine, and isoleucine amino acids. Plant height and phytotoxicity were evaluated at 7, 14, 21, and 28 DAA. The plants were collected at 28 DAA to determine the shoot dry weight. The results indicated that sensitivity to nicosulfuron varied among the eight hybrids studied, with the V2 stage exhibiting higher herbicide accumulation, greater height reduction, and increased phytotoxicity. Aminobutyric acid levels increased in all hybrids after herbicide application, with a stronger correlation between its accumulation and growth inhibition at the V2 stage. These findings suggest that V2 is the most suitable stage for distinguishing hybrid sensitivity to nicosulfuron. Full article

Many specialized metabolites found in plants have significant potential for developing environmentally friendly weed management solutions. This review focuses on the phytotoxic effects of volatile terpenes and phenolic compounds, particularly nepetalactone, an iridoid monoterpenoid from Nepeta species, and phloretin, a dihydrochalcone predominantly found in the genus Malus. We highlight current findings on their herbicidal effects, including morphological, physiological, and biochemical responses in target plants. These results underscore their potential for developing sustainable herbicides that could control weeds with minimal environmental impact. We also discuss their soil persistence and methods to enhance their solubility, chemical stability, and bioavailability. Additionally, the possible effects on non-target organisms, such as pollinators, non-pollinating insects, and soil microbiota, are considered. However, further research and a deeper understanding of their long-term ecological impact, along with a resistance development risk assessment, is essential for the potential development of bioherbicides that could be applied in sustainable weed management practices. Full article

Iron-based metal–organic frameworks (Fe-MOFs) are widely used for agricultural chemical delivery due to their high loading capacity, and they also have the potential to provide essential iron for plant growth. Therefore, they hold significant promise for agricultural applications. Evaluating the plant biotoxicity of Fe-MOFs is crucial for optimizing their use in agriculture. In this study, we used the natural biomacromolecule carboxymethyl cellulose (CMC) to encapsulate the Fe-MOF NH₂-MIL-101 (Fe) (MIL). Through hydroponic experiments, we investigated the biotoxic effects of Fe-MOFs on rice before and after CMC modification. The results show that the accumulation of iron in rice is dependent on the dose and the exposure concentration of Fe-MOFs. CMC modification (MIL@CMC) can reduce the release rate of Fe ions from Fe-MOFs in aqueous solutions with different pH values (5 and 7). Furthermore, MIL@CMC treatment significantly increases the absorption of iron by both the aboveground and root parts of rice. MIL@CMC significantly alleviated the growth inhibition of rice seedlings and increased the aboveground biomass of rice under medium- to high-exposure conditions. Specifically, in rice roots, MIL induced a more intense oxidative stress response, with significant increases in the activities of related antioxidant enzymes (CAT, POD, and SOD) and MDA content. Our results demonstrated that the encapsulation of NH₂-MIL-101(Fe) using CMC effectively alleviated oxidative damage and promoted the uptake and growth of iron in rice. These findings suggest that rational modification can have a positive effect on reducing the potential phytotoxicity of MOFs and improving their biosafety in agricultural applications. Full article

In Europe, food and agricultural waste amount to millions of tonnes annually. Effective management and valorisation of these residues result in environmental benefits and foster opportunities within the circular economy. Composting has emerged as a sustainable method to convert waste into fertiliser, enhancing soil fertility, water retention, and crop resilience against diseases. However, an adequate compost production process is vital to obtain a functional fertiliser. In this study, a controlled conditions self-produced compost from horticultural waste (C1) was compared against two other commercial composts, one of similar vegetable origin (C2) and another from chicken manure (C3). Physicochemical parameters and nutrient contents in the three compost types were analysed, and phytotoxicity and plant development tests were carried out on Lolium multiflorum Lam. seeds and Pistacia lentiscus L. seedlings. C1 presented fertility and germination parameters similar to C3 and showed the best seedling development. In contrast, C2 showed low levels of fertility, germination, and plant development because of impurities and possible substances inhibiting plant growth, suggesting inadequate compost formation processes. Finally, C3, although it presented germination data similar to C1, produced the worst results in the development of seedlings, probably because of high salinity values and low phosphorus content. Full article

Systemic fluorescence tracers introduced into crop plants provide an active signal for crop–weed differentiation that can be exploited for precision weed management. Rhodamine B (RB), a widely used tracer for seeds and seedlings, possesses desirable properties; however, its application as a seed treatment has been limited due to potential phytotoxic effects on seedling growth. Therefore, investigating mitigation strategies or alternative systemic tracers is necessary to fully leverage active signaling for crop–weed differentiation. This study aimed to identify and address the phytotoxicity concerns associated with Rhodamine B and evaluate Rhodamine WT and Sulforhodamine B as potential alternatives. A custom 2D fluorescence imaging system, along with analytical methods, was developed to optimize fluorescence imaging quality and facilitate quantitative characterization of fluorescence intensity and patterns in plant seedlings, individual leaves, and leaf disc samples. Rhodamine compounds were applied as seed treatments or in-furrow (soil application). Rhodamine B phytotoxicity was mitigated by growing in a sand and perlite media due to the adsorption of RB to perlite. Additionally, in-furrow and seed treatment methods were tested for Rhodamine WT and Sulforhodamine B to evaluate their efficacy as non-phytotoxic alternatives. Experimental results demonstrated that Rhodamine B applied via seed pelleting and Rhodamine WT used as a direct seed treatment were the most effective approaches. A case study was conducted to assess fluorescence signal intensity for crop–weed differentiation at a crop–weed seed distance of 2.5 cm (1 inch). Results indicated that fluorescence from both Rhodamine B via seed pelleting and Rhodamine WT as seed treatment was clearly detected in plant tissues and was ~10× higher than that from neighboring weed plant tissues. These findings suggest that RB ap-plied via seed pelleting effectively differentiates plant seedlings from weeds with reduced phytotoxicity, while Rhodamine WT as seed treatment offers a viable, non-phytotoxic alternative. In conclusion, the combination of the developed fluorescence imaging system and RB seed pelleting presents a promising technology for crop–weed differentiation and precision weed management. Additionally, Rhodamine WT, when used as a seed treatment, provides satisfactory efficacy as a non-phytotoxic alternative, further expanding the options for fluorescence-based crop–weed differentiation in weed management. Full article

Seed enhancements involve post-harvest modifications that improve germination and plant performance. One form of enhancement involves coatings, which encompasses encrusting, pelleting, and film coats. These coatings may contain agrichemicals, such as fungicides and insecticides, and can foster conformational changes that improve the plantability of small or irregularly shaped seeds. Seed encapsulation using pharmaceutical capsules can be viewed as an extension of seed coatings where seeds and other beneficial agrichemicals can be combined into a single plantable unit. For many crops, direct contact with high levels of conventional fertilizers may induce some level of phytotoxicity, and early studies involving fertilizer-enriched seed coatings resulted in decreased seedling emergence and diminished plant performance. Encapsulation, however, provides greater delivery volumes compared to other coatings and may offer some degree of separation between seeds and potentially phytotoxic agrochemicals. This study considered tomato seed encapsulation with controlled-release fertilizers. In general, seed exposure to gelatin-based capsules delayed germination by 2- to 3- days. Nevertheless, seed encapsulation improved plant performance including increased plant height and dry mass production by as much as 75 and 460%, respectively. These growth responses mitigated any effects attributed to germination delays. Moreover, higher levels of controlled-release fertilizers (≥800 mg) fostered earlier flower induction by up to 3 weeks. Collectively, the results suggest that seed encapsulation can be an effective way to deliver fertilizers to plants in a manner that could reduce overall fertilizer application rates and possibly lessen the quantity of plant nutrient input necessary for tomato cultivation. Full article

The Chinese red pine, Pinus tabulaeformis, is one of the most important evergreen conifer trees in China. It is widely planted in southern Gansu Province and is commonly used for garden trees, hedges, windbreaks, and soil and water conservation. However, Matsucoccus sinensis, a scale insect, has become a major pest of the P. tabulaeformis forests, and its life history and biological characteristics remain unknown. In this study, we investigated the biological characteristics, male cocoon emergence, adult mating period, and egg developmental period of M. sinensis, providing valuable insights for its prevention and control. We conducted continuous observation of the different developmental stages of M. sinensis, both in the laboratory and in P. tabulaeformis fields. The least squares method was used to calculate the egg developmental period of M. sinensis. Our results showed that the scale insect is a monophagous species with one generation occurring per year. The second-instar nymphs overwinter on the needles in the medium shell and reproduce sexually, without parthenogenesis. Male M. sinensis adults reach their peak appearance at the end of April in the study region. The peak emergence of male cocoons occurred between 2:00 AM and 4:00 AM, and the adult mating period lasted from 11:00 AM to 13:00 PM. The larvae of M. sinensis attack the needles of P. tabulaeformis. The nymphs crawled and moved to the inner base of the needles, with first- to third-instar nymphs fixing themselves to the needles to feed. The effective accumulated temperature and starting temperatures for the development of M. sinensis eggs were found to be 86.1 °C and 3.5 °C, respectively. Overall, understanding the biology and life history of M. sinensis is essential for identifying key developmental stages and determining the optimal timing for pest control, ultimately aiding in the development of targeted management strategies to protect P. tabulaeformis forests from this emerging pest. Full article