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Coastal areas are facing increasing heavy metal contamination from various human activities, posing a severe threat to aquatic and coastal biodiversity. Mangroves, abundant in coastal and marine ecosystems, are particularly vulnerable to the accumulation of toxic inorganic pollutants and heavy metals (HMs). Mangroves have proved to be effective in mitigating heavy metal pollution through a range of mechanisms, including avoidance, chelation, sequestration, tolerance, excretion, and filtration. Studies highlighted a higher metal bioconcentration of metals in mangrove roots compared to leaves, indicating their remarkable endurance capability towards high levels of HMs. The uptake of HMs by mangrove roots occurs through passive diffusion across cell plasma membranes or active transport, regulated by metal ion transporters and influenced by electrochemical and/or concentration potential gradients. In phytoremediation strategies, mangrove plants employ several physiochemical mechanisms to avoid HMs uptake, such as cell wall immobilization, complexation with biomolecules like phytochelatins (PCs), and extracellular barriers at the root endodermis. Moreover, mangroves can develop iron-plaques on their root surface, acting as reservoirs for immobilized HMs and significantly influencing their sequestration, particularly in wastewater containing Cr, Pb, and Ni ions. Mangroves would also trigger antioxidant defenses to cope with the absorbed HMs and normalize the excessive production of reactive oxygen species (ROS)-mediated oxidative stress. However, the antioxidant response in mangroves varies depending on the concentration and type of toxic HMs, plant species, and exposure duration. Additionally, mangroves excrete excessive amounts of HMs through salt glands via adaxial trichomes, allowing them to mitigate phytotoxicity. Although mangroves demonstrate a high tolerance capacity towards HMs, hydrological alteration, deforestation, marine construction, and marine anthropogenic activities pose significant threats to several global mangrove species. In conclusion, conducting multiple toxicity tests using early mangrove seedlings are imperative that threshold effect concentrations of various HMs be determined under natural environmental conditions encompassing nutrients, salinity, temperature, and the presence of several contaminants. Besides, long-term, large-scale mesocosm experiments in real-field settings should be conducted in future to obtain more realistic and reliable insights into the uptake and tolerance of HMs in mangroves. [Display omitted] • Coastal ecosystem is endangered due to heavy metal contamination due to anthropogenic activities. • Mangroves ecosystem faced adverse effects of HMs toxicities. • Mangroves species mitigate HMs toxicities dependent on HMs type and concentration. • Mangroves tolerate HMs toxicity through cell wall immobilization, complexation with biomolecules and extracellular barriers. • Mangroves Phytoremediate HMs phytotoxicity through salt glands via adaxial trichomes. [ABSTRACT FROM AUTHOR]

Nanotechnology offers many potential solutions for sustainable agroecosystem, including improvement in nutrient use efficiency, efficacy of pest management, and minimizing the adverse environmental effects of agricultural production. Herein, we first highlighted the integrated application of nanotechnology and precision agriculture for sustainable productivity. Application of nanoparticle mediated material and advanced biosensors in precision agriculture is only possible by nanochips or nanosensors. Nanosensors offers the measurement of various stresses, soil quality parameters and detection of heavy metals along with the enhanced data collection, enabling precise decision-making and resource management in agricultural systems. Nanoencapsulation of conventional chemical fertilizers (known as nanofertilizers), and pesticides (known as nanopesticides) helps in sustained and slow release of chemicals to soils and results in precise dosage to plants. Further, nano-based disease detection kits are popular tools for early and speedy detection of viral diseases. Many other innovative approaches including biosynthesized nanoparticles have been evaluated and proposed at various scales, but in fact there are some barriers for practical application of nanotechnology in soil-plant system, including safety and regulatory concerns, efficient delivery at field levels, and consumer acceptance. Finally, we outlined the policy options and actions required for sustainable agricultural productivity, and proposed various research pathways that may help to overcome the upcoming challenges regarding practical implications of nanotechnology. [Display omitted] • Nanotechnology, an innovative scientific field, is now applied in almost all scientific studies. • Integrated application of nanotechnology with precision agriculture can sustain the agricultural production. • Various kinds of nano-sensors and biosynthesized nanoparticles are applied in agriculture for better crop productivity. • Excessive nanoparticles application is a serious concern due to their unknown release in environmental compartments. • Toxicity concerns causing nanotechnology application limited, especially related to human health should be investigated. [ABSTRACT FROM AUTHOR]

A two-year experiment was conducted at Student Research Farm, Department of Agronomy, University of Agriculture, Faisalabad (31.4533° N, 73.0585° E) during 2020 and repeated in 2021 for the accuracy of the results. The treatments were T0 Control (recommended fertilizers at 20:60 NP kg ha−1), T1: 50% of recommended vermicompost (FYM) + 50% of recommended fertilizers, T2: 25% of recommended vermicompost (FYM) + 25% of recommended compost (FYM) + 50% of recommended fertilizers, T3: 50% of recommended vermicompost (wheat straw) + 50% of recommended fertilizers, T4: 25% of recommended vermicompost (wheat straw) + 25% of recommended compost (wheat straw) + 50% of recommended fertilizers, T5: 50% of recommended vermicompost (rice straw) + 50% of recommended fertilizers and T6: 25% of vermicompost (rice straw) + 25% of recommended compost (rice straw) + 50% of recommended fertilizers. It was concluded from this study that 50% vermicompost (produced from FYM, rice and wheat straw) mixed with 50% recommended fertilizers showed excellent results. 25% vermicompost (produced from FYM, rice and wheat straw) and 25% compost (produced from farmyard manure, rice straw and wheat straw) mixed with 50% recommended fertilizers showed intermediate results, whereas control showed minimum results in the mungbean crop and soil fertility decreased in the T0 treatment. [ABSTRACT FROM AUTHOR]