Metal-Based Nanopesticides for Seed Protection

Introduction: Seeds and grains are vital components of sustainable food systems. Healthy seeds produce healthier, more viable seedlings, contributing to effective agricultural practices. Currently, agriculture faces a variety of challenges including changing environmental conditions such as salinity, drought, accumulation of heavy metals in soils and climate change, which can negatively impact seed germination, seedling development and ultimately crop yield. Seed quality can also be affected by seed-borne diseases and destroyed by insects and other pests. To control and prevent various pests, diseases and nutritional deficiencies, various pesticides (fungicides, insecticides, fertilizers and fertilizer enhancers) are used in seed treatment. However, these chemicals are expensive and harmful to health, seed pathogens develop resistance, and the chemicals leach into the soil causing problems in water sources and soil, reducing the activity of beneficial microorganisms. For this reason, it is essential to implement sustainable agricultural practices that protect seeds from pests and insects while preserving the agro-ecosystem. Nanotechnology has proven to be a modern tool to overcome the shortcomings of traditional pesticide preparation and application techniques. Formulations that contain nano-dimensional active pesticide ingredients with entirely new properties are called nanopesticides. Therefore, the aim of the present study is to highlight the role and application of various nanoparticles in the formulation of nanopesticides for seed and crop protection. Materials and methods: The present article has been prepared by studying and reviewing the published literature on the role of nanopesticides for seed protection. Results and Discussion: Nanomaterials such as silver, gold, iron oxide, titanium oxide, copper, and zinc oxide, etc. have been used as nanopesticides. For example, silver nanoparticles have been effective against plant pathogens due to their bactericidal, antifungal, antiviral, and antibacterial properties. Sankar and Abideen investigated the nanopesticidal effects of silver and lead nanoparticles against the pest Sitophilus oryzae. On plant surfaces, nanopesticide formulations can improve droplet adhesion, thereby increasing the dispersion and bioactivity of the active ingredients. Thus, nanopesticides are more effective than conventional pesticides in controlling crop pests. Nanopesticides not only improve the dispersion of pesticides, but also increase their bioavailability by facilitating the release of their beneficial components. Unlike conventional pesticide formulations, nanopesticides slowly release their active ingredients at a predetermined rate, achieving the desired efficacy and longevity. By encapsulating pesticides into nanopesticides, the active ingredients of the pesticide are protected from premature degradation and direct release into human health. Metal and metal oxide nanoparticles have been proposed to be biocidal in three ways: (۱) they kill microorganisms through photocatalysis by releasing superoxide radicals that disrupt molecular structures; (۲) they disrupt cell membranes by accumulation of metal nanoparticles; and (۳) they disrupt DNA replication by uptake of metal ions. Thus, the molecular mechanisms of nanopesticides for seed protection include inhibition of cell wall synthesis, depolarization of cell membranes, inhibition of protein synthesis, inhibition of amino acid synthesis, and inhibition of metabolic pathways of pests and microorganisms. Nanopesticide-mediated ROS not only kill seed pathogens but also improve seed and plant defense by activating antimicrobial peptides and secondary metabolites in plants grown from nano-treated seeds. Therefore, ROS generated by nanoparticle interactions may disrupt plant secondary metabolism and cause plants to produce antibacterial secondary metabolites to defend themselves against pathogens. Conclusion: Therefore, the smart nanopesticides can overcome the limitations faced by conventional applications in promoting plant growth. Also, the production and applications of nanopesticides should be in a cost-effective way and in optimal concentrations with suitable guidelines and a unified regulatory framework for sustainable agriculture.

کلیدواژه ها:

Nanopesticides ، Pathogen ، Protection ، Seed