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Andisols are the least extensive soil order, accounting for less than 1% of Earth´s surface. Chile occupies 50% of the country´s land area for cereal production and is of great importance to agriculture. However, few studies have investigated the performance of cereal production under intercropping in P-deficient Andisols. The objective of this study was to evaluate the effects of two different Fabaceae species and wheat in an intercropping system on root morphology and soil properties. A 2-year field experiment was conducted using a completely randomized block experimental design with a factorial arrangement with two different phosphorus levels and cropping systems (wheat monoculture, wheat/lupine, and wheat/chickpea intercropping). Bulk soil samples were collected from a field that had been cultivated with wheat. Chemical properties, basal soil respiration, and enzymatic activity were measured. The morphological characteristics of wheat roots and crop yield were also determined. According to the multiple linear regression model (p <.001), this relative yield was related to an increase in phosphatase activity and root biomass. Furthermore, the Land Equivalent Ratio (LER) of the wheat/lupine intercrop surpassed 1 in both seasons, indicating improved soil and nutrient utilization. In contrast, the wheat/chickpea intercrops had LER values lower than one during the second season. This confirmed that wheat/lupine intercropping is a recommended practice for enhancing ecosystem services and agricultural production in Andisols. [ABSTRACT FROM AUTHOR]

The widespread presence of microplastics (MPs) in agricultural soils raises concerns regarding their impact on crop health and productivity, particularly in legumes, which are known to have soil-enhancing properties. This study investigated the effects of low-density polyethylene (LDPE), polypropylene (PP), and polyamide (PA) MPs on white lupine (Lupinus albus L.). Plants were cultivated for 110 days in glass pots containing 700 g of volcanic soil mixed with 2% w/w MPs, with four treatments (control, LDPE, PP, and PA) and five replicates each. The results indicated that PP increased soil ammonium and available nitrogen by 71% and 60%, respectively, compared to the control. LDPE increased root length by 3% and decreased chlorophyll content by 2.7%, whereas PA increased chlorophyll levels by 3.5%. Oxidative stress markers were significantly elevated in the LDPE and PA treatments, with 12% and 5.4% increases, respectively, compared with the control. However, no significant differences were observed in enzyme activity or basal soil respiration. These findings contribute to the understanding of how short-term exposure to MPs affects agricultural soils and emphasize the necessity for long-term studies to elucidate their potential effects. [ABSTRACT FROM AUTHOR]

Background: Nitric oxide (NO) is an antimicrobial and anti-biofilm agent with significant potential for combating biofilm-associated infections and antibiotic resistance. However, owing to its high reactivity due to the possession of a free radical and short half-life (1–5 s), the practical application of NO in clinical settings is challenging. Objectives: This review explores the development of NO-releasing nanoparticles that provide a controlled, targeted delivery system for NO, enhancing its antimicrobial efficacy while minimizing toxicity. The review discusses various NO donors, nanoparticle platforms, and how NO disrupts biofilm formation and eradicates pathogens. Additionally, we examine the highly encouraging and inspiring results of NO-releasing nanoparticles against multidrug-resistant strains and their applications in medical and environmental contexts. This review highlights the promising role of NO-based nanotechnologies in overcoming the challenges posed by increasing antibiotic resistance and biofilm-associated infections. Conclusions: Although NO donors and nanoparticle delivery systems show great potential for antimicrobial and anti-biofilm uses, addressing challenges related to controlled release, toxicity, biofilm penetration, resistance, and clinical application is crucial. [ABSTRACT FROM AUTHOR]

Plantago lanceolata L. (plantain) increases herbage dry matter (DM) production and quality during warm and dry conditions due to its deep roots and drought tolerance and reduces nitrogen losses in grazing systems compared to traditional pastures. However, plantain density usually declines after the third growing season, mainly due to defoliation management. The effects of defoliation frequency and intensity on water-soluble carbohydrate (WSC) reserves and below-ground plant responses need further research to optimize grazing strategies for improved productivity and sustainability of grazing systems. Our study investigated the effects of defoliation frequencies (15, 25, and 35 cm of extended leaf length, ELL) and intensities (5 and 8 cm of residual heights) on morphological traits and WSC concentrations in plantain biomass under controlled environmental conditions. Defoliation frequency significantly influenced morphological and chemical characteristics and biomass distribution more than residual height. Less frequent defoliations promoted above-ground herbage DM production, reproductive stems, and root biomass. Root architecture showed adaptations in response to defoliation frequency, optimizing resource acquisition efficiency. Frequent defoliation reduced high molecular weight WSC concentrations in leaves, affecting regrowth capacity and DM mass. A defoliation frequency of 25 cm ELL (~15 days) balances herbage production and root development, promoting long-term pasture sustainability. [ABSTRACT FROM AUTHOR]

Microplastics (MPs) are a significant threat to soils. However, there is scarce information on the impact of MPs on soil properties, particularly in volcanic ashderived soils. The objective of this study was to evaluate the impact of polyamide (PA) and low-density polyethylene (LDPE) MPs on the biological and chemical characteristics of an Andisol from central Chile. Twenty-one parameters were evaluated, including pH, electrical conductivity (EC), total organic carbon (TOC), dissolved organic carbon (DOC), total phosphorus (TP), available phosphorous (AP), available nitrogen (AN), inorganic nitrogen forms (NH4 +, NO2 - and NO3), carbohydrates (CHO), polyphenols (POLs), humic substances, soil basal respiration (SBR) and activities of soil enzymes such as dehydrogenase, ß-glucosidase, phosphatase and urease. For this, a microcosm was set up in clay pots in an incubation chamber at 21°C and 60% soil moisture, with the addition of PA and LDPE at doses of 1% and 3% w/w; a control treatment consisting of microcosm without MPs was also included. After 6 weeks of incubation, PA addition resulted in an increase in TOC and NH4 + by up to 32% and 26%, respectively, and a decrease in NO3 - by 22%. AP decreased by 15%-19% with the addition of PA and LDPE. Similarly, acid phosphatase and ß-glucosidase activities decreased by 15% and 26% with PA and LDPE, respectively. The distance-based linear model (DistLM) was used to analyse relationships in chemical and biological datasets. The analysis revealed that TOC and TP were primary components in the best model for predicting microbiological changes (R2 = .469, AICs = 16.026), indicating that MPs accumulation affects soil carbon cycling and P content. Overall, the results show that MPs addition alters soil chemical and microbiological properties in Andisols, with varying effects depending on the type and dose of MPs, with the highest dose (3%) producing the most marked negative effects. [ABSTRACT FROM AUTHOR]

Mulching suppresses weeds, improves soil biology, and increases physical or bioactive fruit yield in fruit orchards. However, there is no information on its impact on calafate (Berberis microphylla G. Forst.) orchards, which produce berries with high antioxidant content. To address this gap, in 2021, an experiment was conducted to evaluate the effect of 5 years of mulching on soil, plants, and calafate fruit. Four mulching treatments were established: no mulch (control), geotextile, oat straw, and hazelnut shell. All mulches suppressed weeds (43%) and maintained more soil moisture (5%) than the control. Soil microbial activity increased only with hazelnut shell compared with the control, up to 46%. Only oat straw and hazelnut shell increased basal respiration and urease up to 31% and 15% more than the control. Oat straw produced the highest fruit yield with 0.44 t ha−1, while the lowest yield was produced by the control and hazelnut shell with 0.1 and 0.15 t ha−1, respectively. The geotextile with 0.35 t ha−1 of fruit produced no differences between treatments. The ORAC antioxidant capacity was only higher in the control and hazelnut shell, with a mean of 3272 µmol TE 100 g−1. Hazelnut shell mulch is recommended to improve the biological functions of the soil and the antioxidant capacity of the calafate fruit. [ABSTRACT FROM AUTHOR]