Victor Hugo Buttrós

The increasing demand for food driven by population growth, together with climate change, environmental degradation, and the excessive dependence of modern agriculture on synthetic fertilizers and pesticides, has intensified the search for sustainable strategies capable of maintaining crop productivity while reducing environmental impacts. Beneficial interactions between plants, arbuscular mycorrhizal fungi (AMF), and rhizobacteria (RHZb) represent one of the most successful evolutionary adaptations of terrestrial plants and have emerged as fundamental components of climate-smart and sustainable agriculture. Here, we comprehensively review the evolutionary origin of these interactions, the molecular and physiological mechanisms underlying plant recruitment, recognition, and establishment of symbiotic and associative relationships, as well as the structural adaptations that support nutrient exchange between partners. Particular emphasis is given to the complementary roles of AMF and RHZb in improving nutrient acquisition, reprogramming plant phytohormone networks, and enhancing tolerance to biotic and abiotic stresses through coordinated physiological, biochemical, and molecular responses. Finally, recent case studies are discussed to demonstrate how these microorganisms contribute to reducing fertilizer inputs, increasing crop productivity, improving stress resilience, and supporting ecological restoration under diverse agricultural systems. Collectively, the evidence highlights that integrating AMF and RHZb into crop management offers a robust biological strategy to enhance resource-use efficiency and agricultural resilience, providing a solid scientific foundation for the development of next-generation bioinoculants and more sustainable food production systems.

Modern agriculture relies on synthetic agrochemicals, but regulatory pressure, environmental costs, and supply chain volatility are accelerating interest in microbial-based agrochemicals (MBAs) as renewable inputs for sustainable intensification. This review frames MBAs through a circular economy lens, highlighting agricultural byproducts as fermentation feedstocks and formulation carriers to reduce cost and footprint while enabling scale-up. We compare cell-in products, which require viable microorganisms to survive processing, storage, and field stresses and to establish in target niches, versus cell-free products, which depend on maintaining the activity and residence time of metabolites, enzymes, and extracts despite degradation, dilution, and adsorption. We summarize submerged and solid-state fermentation and downstream routes to biomass or clarified bioactive fractions and link formulation families (liquids, solids, granules, encapsulated/controlled-release, immobilized) to delivery routes (seed, soil, foliar, fertigation). We highlight critical quality attributes, release criteria, and validation metrics connecting process control to field performance, then outline barriers (feedstock heterogeneity, batch variability, compatibility, context dependence) and priorities for standardization, mechanism-based stabilization/controlled release, and multienvironment validation.

Brazil leads tropical agriculture, yet annual yield losses from insect pests and concerns over water contamination, non-target impacts, and resistance sustain demand for safer, more efficient control tools. This review synthesizes advances in nanopesticides for Brazil’s major crops (soybean, sugarcane, coffee, and citrus) and is organized into five parts, comprising concepts and definitions; formulation families; modes of action; efficacy evidence from laboratory, greenhouse, and field studies; and environmental and human health risk considerations. Evidence indicates that nano-enabled delivery can increase on-target deposition, prolong residual activity, and match or exceed control at reduced active ingredient loads by improving foliar adhesion, transcuticular transport, plant uptake, and spatiotemporal targeting with pheromone-releasing nanofibers and other dispensers. Because nanoformulations can alter exposure pathways and environmental fate, this review emphasizes nano-specific physicochemical characterization under use conditions, fate and transport in Oxisols and Ultisols, and tropical waters, ecotoxicity panels that include pollinators, aquatic invertebrates, soil biota, and vertebrate surrogates, and scenario-based exposure assessment for applicators, residents, and consumers. The review closes with practical guidance for Brazil: head-to-head efficacy benchmarks against commercial standards, the standardized reporting of release and characterization data, and a nano-specific environmental risk assessment checklist to help realize efficacy gains while protecting environmental and human health.

The emergence of the Guava Root-Knot Nematode ( Meloidogyne enterolobii ) poses a significant threat to tomato yields globally. This study aimed to evaluate the impact of collagen and chitin soil amendments on soil microbial composition and function (fungal and bacterial communities), and their effects on tomato plant health and M. enterolobii infection under standard (5,000 eggs plant ^-1 ) and high (50,000 eggs plant ^-1 ) inoculum pressure. Conducted in a greenhouse setting, the study investigated the effectiveness of these amendments in nurturing beneficial microbial communities across both native and agricultural soils. Both collagen and chitin were effective in reducing nematode egg counts up to 66% and 84% under standard and high inoculum pressure, respectively and enhance plant health parameters (biomass and chlorophyll content). Moreover, a microbiome shift led to an increase in bacterial ( Kitasatospora, Bacillus, and Streptomyces ) and fungal ( Phialemonium ) genera, known for their chitinase, collagenase, and plant-parasitic nematode control. Among the microbes, Streptomyces spp. were found among the core microbiome and associated with a lower disease incidence assessed through a phenotype-OTU network analysis (PhONA). Under standard inoculum a higher metabolite expression was observed with the amino acid class being the majority among the metabolite groups. The findings highlight the potential of collagen and chitin to mitigate Meloidogyne enterolobii infection by fostering beneficial soil microbial communities.