TL;DR
This review synthesizes current knowledge on the structural classes of plant-derived compounds and critically evaluates their applications as biocontrol agents against bacterial phytopathogens, highlighting their potential integration into sustainable resilience and global food security.
Pre- and postharvest losses caused by fungal infections represent one of the greatest constraints in agricultural production worldwide. Due to increasingly stringent regulations, as well as environmental and health concerns associated with their use, synthetic fungicides have been restricted, driving the development and application of sustainable alternatives within the framework of integrated plant disease management. Among these, Actinobacteria (also referred to as Actinomycetota) have attracted considerable attention over the past decades due to their versatile metabolites and plant growth-promoting properties, supporting their potential application as bacterial biocontrol agents. Their activity against phytopathogenic fungi is largely associated with direct antagonistic mechanisms. Currently, special attention is paid to the excreted secondary metabolites, lytic enzymes, volatile organic compounds and their in vitro antifungal activity. Therefore, this review summarizes current knowledge on these direct mechanisms, aiming to support the future application of actinobacteria and their metabolites as part of biological plant disease management strategies.
Overall, this review presents the versatile function of Trichoderma spp.
The global crop production & food security faces major threat from economic loss and food risk. This review navigates the labyrinthine diversity of fungal world, their different way of nutrition, categorization of phytopathogenic fungi & the insidious mechanisms of pathogenicity that enable their successful parasitism which compromise plant health. Interaction between phytopathogenic fungi & host is dynamic where fungal virulence driven by the production of diverse toxins. The significant impact of disease on yield of crops, associated with the production of toxins. Additionally, developing challenges of fungal resistance to antifungal agent demands for the development of novel regulatory approaches. This review draws attention to the potential of phytochemicals as naturally occurring substances with antifungal properties. Plants, across a broad spectrum of taxonomic groups contain abundant bioactive compounds that effectively inhibit the growth of fungi. Use of these natural compounds as environmentally friendly and sustainable alternatives for crops, demonstrating their ability to reduce the effect of fungal disease and encourage sustainable food production.
Botanical gardens are highly heterogeneous plant systems characterized by high taxonomic diversity, with numerous plant taxa represented within confined areas, and complex ecological interactions that create unique challenges for pest management. Conventional IPM strategies, designed for simplified agroecosystems, often fail to address complex pest pressures in curated environments. Microbial biostimulants have emerged as promising components of sustainable IPM strategies by enhancing plant defense responses, improving stress resilience, and reducing reliance on chemical inputs. This review synthesizes current knowledge on microbial biostimulants, including plant growth-promoting rhizobacteria, arbuscular mycorrhizal fungi and endophytic microorganisms, in modulating plant defense against insect herbivores. These beneficial microbes enhance plant resistance through multiple mechanisms. They activate induced systemic resistance and modulate key phytohormones, including jasmonic acid, salicylic acid, and ethylene. Additionally, they regulate calcium-dependent and reactive oxygen species-mediated defenses. Microbially induced changes in plant secondary metabolites and volatile organic compounds further influence herbivore behavior and trophic interactions. Emphasis is placed on integrating microbial biostimulants into IPM frameworks tailored to botanical gardens. This highlights compatibility with biological control agents and reduced reliance on synthetic pesticides. Despite promising advances, challenges remain, including context-dependent efficacy, host specificity and limited long-term validation. Overall, microbial biostimulants offer a promising tool for enhancing IPM in biodiversity-rich botanical gardens, although further long-term validation is needed to fully assess their sustainability and effectiveness.
Trichoderma species are widely investigated and commercially applied as eco-friendly biocontrol agents in sustainable agriculture. These filamentous fungi protect plants through multiple complementary mechanisms, including mycoparasitism, antibiosis, competition for nutrients and ecological niches, and induction of systemic resistance in host plants. These activities are mediated by a diverse array of secondary metabolites, hydrolytic enzymes, and signaling pathways that collectively suppress pathogens and enhance plant health. Beyond disease control, selected Trichoderma strains promote plant growth by improving nutrient acquisition, modulating phytohormone signaling, and increasing tolerance to abiotic stresses. This review summarizes recent advances in the mechanisms underlying Trichoderma spp. mediated biocontrol, with particular emphasis on secondary metabolites, formulation strategies, commercialization, and field applications. Commercial products are available in various formulations, including wettable powders, granules, and liquid preparations, and have demonstrated efficacy against several economically important plant diseases under field conditions. However, their performance remains highly dependent on strain characteristics, host species, environmental conditions and agricultural practices, resulting in inconsistent efficacy across agroecosystems. Recent progress in genomics, transcriptomics, and metabolomics has substantially improved our understanding of Trichoderma–plant–pathogen interactions and revealed considerable strain-specific variation in biocontrol and plant growth-promoting traits. Future research should prioritize strain-specific optimization, formulation stability, microbiome-informed applications, and improved field predictability. Overall, Trichoderma spp. Represents a valuable component of integrated disease management, offering an effective and sustainable alternative to synthetic pesticides.