Microplastics (MPs) are an emerging global change factor with the potential to affect key agroecosystem services. Yet, MPs enter soils with highly variable properties (e.g., type, shape, size, concentration, and aging duration), reflecting their heterogeneous chemical compositions and diverse sources. The impacts of MPs with such varying properties on agroecosystem services remain poorly understood, limiting effective risk assessment and mitigation efforts. We synthesized 6315 global observations to assess the broad impacts of microplastic properties on key agroecosystem services, including crop productivity and physiology, soil carbon sequestration, nutrient retention, water regulation, and soil physical and microbial properties. MPs generally caused significant declines in aboveground productivity, crop physiology, water-holding capacity, and nutrient retention. However, the direction and magnitude of these effects varied considerably depending on the specific properties of MPs. The hazards posed by MPs to aboveground productivity, antioxidant systems, and root activity were size- and dose-dependent, with larger particles at higher concentrations inducing greater damage. Prolonged microplastic exposure impaired crop photosynthesis and soil nutrient retention, but most other ecosystem services (e.g., belowground productivity, antioxidant systems, and root activity) showed gradual recovery over time. Fiber-shaped MPs positively influenced crop aboveground and belowground productivity and soil carbon sequestration, potentially due to their linear configuration enhancing soil aggregation and connectivity. Polymer type emerged as the most prominent driver of the complex and unpredictable responses of agroecosystem services to MPs, with biodegradable polymers unexpectedly exerting larger negative effects on crop productivity, root activity, photosynthesis, and soil nutrient retention than other polymers. This synthesis underscores the critical role of microplastic properties in determining their ecological impacts, providing essential insights for property-specific risk assessment and mitigation strategies to address microplastic pollution in agroecosystems.

In conventional agricultural practices, pesticides are applied to protect crops from harmful insect pests; however, pervasive usage in high-yield crop systems poses a significant risk to the viability and sustainability of agroecosystems. Agricultural output may be adversely affected by pesticide deposition in the soil as it affects biochemical interactions between plants and soil. Pesticides cause oxidative stress by blocking physiological and biochemical pathways and disrupting the photosynthetic machinery of plants. When exposed to abiotic challenges, plant growth regulators (PGRs) such as auxin, gibberellins, cytokinin and abscisic acid (ABA), salicylic acid (SA), jasmonic acid (JA), brassinosteroids (BR), and 24-epibrassinolides (EBL) reduce pesticide toxicity by strengthening antioxidant defence mechanisms and enhancing tolerance to stressful conditions. By modulating a variety of physio-biochemical mechanisms, PGRs reduce pesticide toxicity in intact plants. Furthermore, PGRs eliminate reactive oxygen species (ROS) generation by inducing antioxidant enzyme production. Pesticide residues in plant compartments are reduced as a result of PGR-mediated increase in pesticide degradation. This review provides a detailed account of the potential role of PGRs in pesticide detoxification and growth promotion in plants. This work examines several elements of plant pesticidal reactions and assesses how PGRs support plants in tolerating pesticides. The underlying mechanisms during pesticide stress are also discussed. The need for additional study on PGR applications is also emphasized.

The increasing global population has raised concerns about meeting growing food demand. Consequently, the agricultural sector relies heavily on chemical fertilizers to enhance crop production. However, the extensive use of chemical fertilizers can disrupt the natural balance of the soil, causing structural damage and changes in the soil microbiota, as well as affecting crop yield and quality. Biofertilizers and biostimulants derived from microalgae and cyanobacteria are promising sustainable alternatives that significantly influence plant growth and soil health owing to the production of diverse biomolecules, such as N-fixing enzymes, phytohormones, polysaccharides, and soluble amino acids. Despite these benefits, naturally producing high-quality microalgal biomass is challenging owing to various environmental factors. Controlled settings, such as artificial lighting and photobioreactors, allow continuous biomass production, but high capital and energy costs impede large-scale production of microalgal biomass. Sustainable methods, such as wastewater bioremediation and biorefinery strategies, are potential opportunities to overcome these challenges. This review comprehensively summarizes the plant growth-promoting activities of microalgae and elucidates the mechanisms by which various microalgal metabolites serve as biostimulants and their effects on plants, using distinct application methods. Furthermore, it addresses the challenges of biomass production in wastewater and explores biorefinery strategies for enhancing the sustainability of biofertilizers.

Intercropping is an alternative farming method that maximizes crop yield and resource usage effectiveness, especially in low-input agricultural systems. Legume-based intercropping systems can effectively boost the quality and wheat yield by promoting soil functions and microbial activities. However, changes in the types of legumes and field management can alter the response of crop functions. A three-year field study was conducted on intercropping cultivation of winter wheat variety (Butterfly and Lorien) and legume species (faba bean, incarnate clover, spring pea, winter pea) to assess grain yield and wheat quality in organic farming. Based on the results, Butterfly showed higher grain quality but lower grain yield and yield components than Lorien. Mixtures of legume crops with winter wheat did not significantly differ in wheat grain yield, but grain quality variables were significantly affected. Protein content (PC) was significantly higher in wheat and legume mixtures than in sole wheat by 4 %. PC in wheat + winter pea (Wheat + Wi) and wheat + faba bean (Wheat + Fa) were higher than wheat sown alone. Wet gluten (WG) was higher in Wheat + Wi than in sole wheat and wheat + incarnate clover mixtures (Wheat + In). The rheological parameters evaluated by the Mixolab showed greater wheat quality in Butterfly and legume mixtures. Mixed and row-row intercropping of wheat and legume species did not significantly influence rheological properties. To conclude, customizing wheat yield and grain quality under the effect of winter wheat and legume mixtures requires considering the optimal solution based on different cultivates, wheat varieties and legume species to achieve the desired response.

Agricultural practices that lead to soil carbon sequestration may be a win-win strategy for mitigating global warming and improving soil fertility and resource use efficiency. The mechanisms through which soil organic carbon (SOC) concentration affects crop yields are numerous but difficult to separate. The objective of this study was to disentangle these processes and estimate to what extent the yield response to SOC is mainly driven by changes in physical or biochemical properties and processes. This was achieved by analysing the response of yields in continuous maize to SOC concentrations during 20 years (2000-2019), which had evolved in 14 experimental treatments in a Swedish long-term field experiment at Ultuna since 1956, ranging from 0.94% to 3.65% in the topsoil (0-20 cm). Average maize yields during this period varied between 1.9 and 8.4 Mg dry mass per hectare in the different treatments. The treatments comprise applications of different mineral nitrogen (N) fertilizers and organic amendments and combinations thereof. Our analysis showed that maize yield in the treatments that were not severely limited by nitrogen supply or soil acidity increased by 16% for each percentage unit increase in SOC. We applied the widely used concept of critical N concentration in plant biomass to diagnose the N status in maize in the different treatments (N nutrition index [NNI]) and parameterized a response function between yield and pH (RpH). Dry soil bulk density (BD) was used as a proxy for soil physical properties. These three variables NNI, RpH and BD explained 95% of the variation in maize yields among treatments. Further analysis of the relationship between BD, SOC and plant available water capacity revealed that about two thirds of the yield increases in response to SOC change could be ascribed to associated changes in soil physical properties. Our analysis suggests that the extra storage capacity of water, which increased by up to 15 mm in the topsoil for each unit percentage increase in SOC, was the main driver for the observed yield responses. We conclude that measures for increasing SOC in soils most likely are an effective adaptation strategy for reducing the risk of crop damage during dry spells, which probably are becoming more frequent in the future due to climate change, even in relatively humid climates as in Sweden. After about six decades of different agricultural management, soil organic carbon (SOC) concentrations differed by up to a factor of four between the treatments in a Swedish field trial. Crop yields increased by 16% for each unit percentage of SOC increase in the high-N treatments and by 14% in the low-N treatments. image