Plants, the cornerstone of life on Earth, are constantly struggling with a number of challenges arising from both biotic and abiotic stressors. To overcome these adverse factors, plants have evolved complex defense mechanisms involving both a number of cell signaling pathways and a complex network of interactions with microorganisms. Among these interactions, the relationship between symbiotic arbuscular mycorrhizal fungi (AMF) and strigolactones (SLs) stands as an important interplay that has a significant impact on increased resistance to environmental stresses and improved nutrient uptake and the subsequent enhanced plant growth. AMF establishes mutualistic partnerships with plants by colonizing root systems, and offers a range of benefits, such as increased nutrient absorption, improved water uptake and increased resistance to both biotic and abiotic stresses. SLs play a fundamental role in shaping root architecture, promoting the growth of lateral roots and regulating plant defense responses. AMF can promote the production and release of SLs by plants, which in turn promote symbiotic interactions due to their role as signaling molecules with the ability to attract beneficial microbes. The complete knowledge of this synergy has the potential to develop applications to optimize agricultural practices, improve nutrient use efficiency and ultimately increase crop yields. This review explores the roles played by AMF and SLs in plant development and stress tolerance, highlighting their individual contributions and the synergistic nature of their interaction.

Arbuscular mycorrhizal fungi (AMF) are a ubiquitous group of soil microorganisms that form symbiotic relationships with the roots of over 80% of terrestrial plant species. These beneficial fungi are crucial in plant growth, nutrition enhancement, and abiotic and biotic stress resilience. This review explores the AMF synergistic benefits including their capacity to interact with plant roots system to enhance nutrient absorption, improve stress resilience, and confer disease resistance, and their potential applications in sustainable agriculture. The Review integrates recent insights illustrating the molecular processes responsible for improving plant defense mechanisms by AMF, including the modulation of signaling pathways. It highlights the importance of AMF-induced systemic resistance in enhanced abiotic and biotic stress resistance. Moreover, the article provides an integrative perspective on applying AMF toward sustainable plant protection. Within this context, we discussed how these fungi improve plant performance, including enhanced nutrient acquisition, increased tolerance to environmental stressors, and enhanced protection against pathogens by improving plant resistance to biotic stress through the activation of the plant immune system. We also examine the ecological significance of AMF in maintaining soil health and fertility and highlight the importance of incorporating their management into sustainable agricultural practices. Future research directions and innovative applications are also presented. The literature survey demonstrated these fungi's versatility in improving plant tolerance to several biotic and abiotic stresses. At the scientific level, these abilities are supported by several open-field experiments on different plant species. Available commercial formulations and positive ongoing research of AMF, in combination with other sustainable tools, highlight the solid research outline on these beneficial fungi.

Arbuscular mycorrhizal fungi (AMF) play a crucial role in disease control by establishing symbiotic relationships with plant roots. AMF improve salinity tolerance in plants by regulating the Na⁺/K⁺ ratio through selective ion transport and mediate osmotic regulation by inducing the accumulation of osmotic-compatible solutes such as glycine betaine and proline to enable plant cells to maintain water content and the metabolic balance. AMF can also activate antioxidant defense responses by stimulating enzymes that protect plant cells from harmful oxidation and pathological infections. Plant salinity tolerance induced by AMF depends on abscisic acid (ABA)-dependent signaling mechanisms, calcium-calmodulin-dependent pathways, and reactive oxygen species (ROS)-modulated mitogen-activated protein kinase (MAPK) cascades. Therefore, future research should focus on optimizing the production and field efficacy of AMF-based inoculants, including their combined use with microbial biostimulants, to support the implementation of sustainable agricultural practices.

Tomato (Solanum lycopersicum L.) production is constantly threatened by several fungal pathogens, such as Alternaria solani, the causal agent of early blight disease. In this study, a greenhouse experiment was set up to evaluate the biocontrol ability of arbuscular mycorrhizal fungi (AMF) against A. solani in the presence of reduced doses of fungicides (i.e., captan and copper oxychloride). Disease severity, plant growth traits, chlorophyll and phosphorus content, phenolic compounds, and antioxidant activity were assessed. The effects of fungicide dose on AMF were investigated by root colonization, spore density, and mycorrhizal dependence evaluation. AMF-inoculated and fungicide-treated plants reduced disease severity compared to fungicide-treated and non-mycorrhizal plants, in most cases, regardless of the fungicide dose. AMF improved plant growth, especially when combined with copper oxychloride. However, plant fresh weight decreased in plants treated with the lowest dose of captan (25 g 100 L⁻¹). Overall, AMF colonization decreased in plants with high fungicide doses, while the leaf color parameters did not show differences between treatments. The results suggest reducing the fungicide dose using AMF is possible, particularly for copper oxychloride. Further studies will be required to confirm these data. This integrated approach could offer a sustainable alternative to decrease the use of chemical control.

Microbe-synthesized NanoParticles (MNPs) show great potential for controlling plant diseases, offering advantages over chemical pesticides. MNPs possess unique physical and chemical properties, leading to higher efficacy, lower toxicity, and environmental safety. They can be produced using cost-effective and eco-friendly methods, making them a viable alternative. MNPs exhibit diverse mechanisms of action, including antifungal, antibacterial, and antiviral activities. They can penetrate pathogen cell walls, disrupting their normal processes and causing death or reduced virulence. Additionally, MNPs can activate plant defence mechanisms, enhancing resistance to infections. This chapter provides an overview of MNPs’ applications in plant disease management, exploring microorganisms involved in nanoparticle synthesis and the underlying mechanisms. MNPs offer advantages like cost-effectiveness, environmental friendliness, and specificity in synthesis. However, challenges remain, such as understanding long-term environmental and human health effects, regulatory and economic barriers, and developing efficient delivery systems. Despite these challenges, MNPs have the potential to transform agriculture and promote sustainable practices. Further research is needed to address limitations and overcome barriers. MNPs could become a versatile, environmentally friendly alternative in various fields. With continued progress, they offer a promising solution for plant disease control, fostering sustainable and effective approaches. <!----> <!----> <!----> <!---->

The online version contains supplementary material available at 10.1007/s00572-026-01262-7.