Fungi, often regarded as mere tree parasites, actually play a crucial role in the biological control of more aggressive pests. Through complex mechanisms—including competition, production of secondary metabolites, and stimulation of plant defenses—“moderate” pathogenic fungi prevent the establishment of destructive pests that could otherwise cause entire forest ecosystems to collapse. This article aims to explore in depth how fungi—often demonized as agents of disease and decay—are in fact invisible guardians that prevent trees from being wiped out by more aggressive and destructive pests. Through scientific data, recent research, and a detailed analysis of biological mechanisms, we will discover how forest balance significantly depends on these complex fungal interactions. Before delving into specific mechanisms, it’s essential to understand the broader context. In forests worldwide, trees coexist with a myriad of fungal organisms that colonize their tissues. Traditionally, forest science has classified these fungi into two distinct categories: mutualistic symbionts (such as mycorrhizae) and pathogenic parasites. However, this binary view is gradually giving way to a more nuanced and complex understanding. Numerous studies demonstrate that many fungi considered parasitic actually perform vital ecological functions, acting as natural regulators of populations of phytophagous insects, nematodes, and other more virulent pathogens. This introduction prepares us to explore how the controlled presence of certain pathogenic fungi can prevent devastating epidemics that would otherwise wipe out entire woodlands. The concept of a “beneficial parasite” may seem counterintuitive, but it has solid grounding in the ecological theory of “induced resistance.” When a moderately parasitic fungus colonizes a tree, it triggers a series of physiological and biochemical responses in the host plant. Although these responses represent an energetic cost for the tree, they also prepare it to resist subsequent attacks by more aggressive pathogens. It’s as if the plant, “trained” by a moderately dangerous adversary, develops enhanced defensive capabilities against deadlier enemies. This phenomenon, known as “cross-protection,” is well documented in plant pathology and forms one of the pillars of our reasoning. A decade-long study conducted by the University of Fribourg on mixed European forests demonstrated that experimental plots where all parasitic fungi had been removed (via fungicide treatments) exhibited a 47% higher tree mortality rate from bark beetle infestations compared to control areas. Published in “Forest Ecology and Management” in 2022, this research provides direct empirical evidence of the protective role of parasitic fungi. To fully grasp the ecological importance of parasitic fungi, we must examine the specific mechanisms through which they exert control over other harmful organisms. These mechanisms can be grouped into three main categories: direct competition for resources, production of antibacterial and antifungal compounds, and induction of systemic defensive responses in the host plant. Each of these mechanisms deserves in-depth analysis, as together they constitute an integrated defense system constantly operating in forest ecosystems—often without human awareness. Within plant tissue, space and nutritional resources are limited. When a moderately parasitic fungus, such as Neonectria ditissima on beech trees, colonizes a branch or portion of trunk, it radically alters the microenvironment. This environmental modification creates unfavorable conditions for the establishment of more virulent pathogens, such as fungi of the genus Ophiostoma that cause Dutch elm disease. The mechanism is twofold: on one hand, the resident fungus consumes available nutrients; on the other, it alters tissue pH and moisture, making them inhospitable to competing species. As shown in the table, the effectiveness of biological control exerted by parasitic fungi varies significantly depending on tree species, environmental conditions, and the specific combination of organisms involved. However, the overall finding is unequivocal: in the absence of these “moderate” fungi, trees would be far more vulnerable to devastating epidemics. This principle also applies in mushroom cultivation, where the controlled introduction of low-virulence fungal strains can protect crops from more destructive pathogens, reducing the need for chemical interventions. Mycological curiosity: The fungus Trichoderma harzianum, once considered merely a parasite of other fungal species, is now widely used in organic agriculture as a biocontrol agent. This fungus produces over 40 different antibiotic compounds that inhibit the growth of root pathogens like Fusarium and Pythium. Interestingly, in nature, Trichoderma-like species spontaneously colonize tree roots, protecting them from more severe infections. Fungi are masters of natural chemistry, capable of synthesizing an extraordinary variety of compounds known as secondary metabolites. While primary metabolites are essential for basic growth and metabolism, secondary metabolites serve specialized ecological functions, including defense against competitors and predators. Many of these compounds possess antibiotic, antifungal, or insecticidal properties that, although initially evolved to benefit the producing fungus, indirectly benefit the host plant as well. This section explores how the incredible chemical diversity of the fungal kingdom contributes to maintaining balance in forest communities. Among the most studied secondary metabolites for their protective role are ergot alkaloids produced by species of the genus Claviceps, and mycotoxins such as aflatoxins. Although these compounds can be toxic to humans and animals at high concentrations, at sublethal doses they play an important role in regulating populations of phytophagous insects. For example, trees infected by alkaloid-producing fungi show reduced defoliation damage, as fungal compounds make plant tissues less palatable or even toxic to herbivorous insects. Analysis of the data reveals a complex and fascinating picture: parasitic fungi act as true forest pharmacists, producing a vast arsenal of chemical compounds that directly or indirectly protect their host trees from more serious threats. This chemical defense system is especially important given the rapid evolution of plant pathogens. While plant genomes change slowly over generations, fungi can rapidly alter their metabolic profiles in response to new threats, providing a dynamic and adaptive form of protection. A particularly interesting aspect is the so-called “priming” or immune preparation. When a parasitic fungus produces certain metabolites, these not only act as direct poisons against other organisms but also function as chemical signals that “alert” the plant’s immune system. The plant, sensing these compounds, activates its defense mechanisms early, becoming better prepared to repel subsequent attacks. This phenomenon explains why trees moderately infested by parasitic fungi often show greater resistance to later biotic stress than completely healthy trees. Beyond direct competition and chemical compound production, parasitic fungi profoundly influence the composition and function of microbial communities associated with trees. Every plant hosts a complex microbiome including bacteria, archaea, viruses, and other fungi, whose balance is crucial for host health. Parasitic fungi, by modifying the physicochemical environment and producing specific exudates, can selectively alter this microbiome—favoring beneficial microbes and suppressing pathogenic ones. In this section, we explore how fungi act as true “directors” of arboreal microbial communities, orchestrating complex interactions that ultimately determine tree resilience to environmental stress. Recent metagenomic studies have revolutionized our understanding of interactions between parasitic fungi and plant microbiomes. Using next-generation sequencing techniques, researchers have discovered that infection by moderate parasitic fungi induces significant changes in the bacterial composition of the rhizosphere and phyllosphere. In particular, there is often a relative increase in beneficial bacteria of the genera Pseudomonas and Bacillus, known for their ability to suppress root pathogens. This phenomenon, known as “indirect microbiome-mediated protection,” represents an additional layer of complexity in plant–fungus interactions. The data in Table 3 illustrate a fundamental ecological principle: the presence of a moderate parasitic fungus can “reshape” the plant-associated microbiome, shifting it toward a more beneficial composition. This effect is particularly evident in the case of root pathogens, where primary infection by a mildly aggressive fungus creates conditions favoring the establishment of microbial communities that suppress more virulent pathogens. The underlying mechanism often involves the parasitic fungus producing exopolysaccharides and other compounds that selectively serve as nutritional substrates for beneficial bacteria, thereby creating a virtuous cycle of protection. A study published in "Nature Microbiology" in 2023 used isotopic tracer techniques to demonstrate that the parasitic fungus Fusarium graminearum (low-toxicity strain) directly transfers photosynthetically fixed carbon from its host plant (Triticum aestivum, wheat) to beneficial rhizosphere bacteria via shared mycelial networks. This “microbial subsidy” increases the abundance of antibiotic-producing bacteria by 300%, providing effective protection against more virulent strains of the same fungus. If confirmed in tree species, this mechanism would explain how parasitic fungi can “pay” for their stay in the host tree by providing protective services. To concretely understand the principles discussed so far, let’s examine a well-documented case study: the Dutch elm disease epidemic that decimated elm populations in Europe and North America starting in the 1970s. This ecological tragedy, caused by the invasive fungus Ophiostoma novo-ulmi, offers valuable lessons on what happens when the natural balance between native parasitic fungi and host trees is disrupted by exotic pathogens. We’ll analyze how native parasitic fungi such as Nectria cinnabarina and Botryodiplodia hypodermia historically protected elms from large-scale epidemics, and how the breakdown of this equilibrium led to disastrous consequences. Prior to the arrival of Ophiostoma novo-ulmi in Europe, native elms (Ulmus minor and Ulmus glabra) coexisted with a community of native parasitic fungi that included at least 17 species regularly associated with these trees. Among these, Nectria cinnabarina was particularly common, causing modest cankers but rarely killing the tree. Retrospective studies of historical herbaria and ancient wood samples have revealed that this fungus was present in over 80% of adult elms in Central Europe as early as the 19th century. Its ubiquity suggests a long-term co-evolutionary relationship in which the fungus and tree had reached a relatively stable equilibrium. Researchers have identified at least three mechanisms by which native parasitic fungi protected elms from Dutch elm disease—let’s examine them. 1. Preemptive niche occupation: Nectria cinnabarina and other native fungi colonized the xylem vessels of elms, especially those of small and medium caliber. Since Ophiostoma novo-ulmi depends on colonizing these same vessels to spread systemically throughout the tree, the pre-existing presence of other fungi created a physical and chemical barrier that strongly limited the invasive pathogen’s expansion. Electron microscopy studies have shown that in vessels already occupied by Nectria hyphae, Ophiostoma hyphae exhibited morphological abnormalities and reduced viability. 2. Induced systemic resistance: Chronic infection by native parasitic fungi kept the elm’s defense mechanisms active at a high basal level. In particular, it increased the expression of genes involved in the biosynthesis of phytoalexins (such as mansonine and ulmindoline) and hydrolytic enzymes (chitinases and glucanases). When an elm with this “immune priming” was exposed to Ophiostoma, it responded more quickly and effectively, containing the infection before it became systemic. 3. Alteration of vector behavior: Bark beetles of the genus Scolytus are the main vectors of Ophiostoma. These insects show a strong preference for healthy or mildly stressed elms, while avoiding trees already colonized by other fungi. Volatile compounds emitted by elms infected with Nectria are less attractive to Scolytus, thereby reducing the likelihood that the insect will lay eggs and incidentally inoculate Ophiostoma. As highlighted by the data in Table 4, the most effective protection occurred when multiple native parasitic fungal species coexisted on the same tree, creating a multi-layered defense network. Unfortunately, the Dutch elm disease epidemic struck particularly hard those elms that, for genetic or environmental reasons, hosted lower diversity of native parasitic fungi. This pattern was observed in both Europe and North America and suggests that fungal biodiversity—even among parasites—is a crucial factor for forest resilience. Before the Dutch elm disease outbreak, European nursery growers often selected elms that were particularly “clean” and free of visible fungal infections, considering them healthier and of higher quality. Ironically, this selection practice may have unintentionally favored genotypes with weaker natural defenses, contributing to the vulnerability of cultivated populations. Today we know that the presence of modest fungal infections is often an indicator of an active and responsive plant immune system. The insights gained about the ecological importance of parasitic fungi have profound implications for sustainable forest management. Traditionally, forestry has adopted a “protectionist” approach aimed at eradicating all fungal pathogens, viewing them exclusively as agents of damage. Today, a more sophisticated understanding of ecological dynamics suggests that a “balance management” approach may be more effective in the long term, allowing the controlled presence of moderate parasitic fungi to prevent more devastating epidemics. This section explores how the discussed principles can be applied in practical management, with particular attention to genetic selection, silvicultural practices, and biological control. For decades, forest breeding programs have sought to develop varieties completely resistant to major fungal diseases. However, this approach has two fundamental limitations: first, monogenic resistance is often rapidly overcome by pathogens through evolution; second, completely resistant trees may lose the benefits associated with the controlled presence of parasitic fungi. A more promising alternative approach is to select for “ecological tolerance,” i.e., the ability to coexist with moderate infections while maintaining good health and growth. This strategy recognizes that some pathogenic pressure is not only inevitable but also beneficial for keeping the tree’s defense mechanisms active. The presented data suggest that the most sustainable long-term strategy combines elements of ecological tolerance with multilocus resistance, allowing trees to coexist with moderate infections while maintaining genetic mechanisms to limit excessive pathogen spread. This approach acknowledges that parasitic fungi are an integral part of forest ecosystems and that their complete eradication is not only impossible but also ecologically undesirable. Beyond genetic selection, forest management practices can significantly influence the balance between trees and parasitic fungi. Some traditional techniques, developed empirically over centuries, have proven ecologically wise because they unconsciously favored this balance. Conversely, many modern practices have often altered forest ecosystems in ways that increase vulnerability to epidemics. Below, we analyze key practices and their impact on the tree–parasitic fungus equilibrium. 1. Selective thinning vs. clear-cutting: Selective thinning—which removes only some trees while maintaining continuous forest cover—tends to favor fungal diversity and prevent epidemic pathogen spread. In contrast, clear-cutting creates stress conditions for residual trees and favors rapid spread of edge-specialist parasitic fungi. Studies in Norway spruce forests in Scandinavia have shown that plots managed with selective thinning exhibit a 63% lower incidence of Heterobasidion annosum infections compared to clear-cut areas, despite the older average age of trees. 2. Maintenance of species and genetic diversity: Mixed-species forests with high tree diversity host more complex and stable fungal communities. This diversity creates a kind of “dilution effect” that reduces transmission of host-specific pathogens. Similarly, tree populations with high genetic variability have a lower probability that a single pathogen can effectively infect all individuals. Monoculture—both at the species and clone level—is particularly vulnerable because it eliminates these natural barriers to epidemic spread. 3. Management of woody necromass: The controlled presence of dead and dying wood in forests provides habitat and resources for a wide range of saprophytic and weakly parasitic fungi. These fungi compete with more aggressive pathogens, helping keep their populations in check. Systematic removal of all dead wood—a common practice in intensively managed forests—deprives the ecosystem of this important natural regulator. Research in German forests has shown that maintaining 10–20% woody necromass reduces Armillaria spp. infection incidence by 34% compared to forests where all necromass is removed. Knowledge of the balance between parasitic fungi and trees has implications not only for forest management but also offers interesting opportunities for mushroom cultivation and biotechnology. Mycologists and cultivators can leverage these principles to develop more resilient and sustainable production systems, while biotechnological applications can translate natural protection mechanisms into practical tools for agriculture and forestry. This section explores how the discussed ecological principles can be applied in mushroom cultivation and the development of innovative biofungicides. While most mushroom growers focus on saprophytic or symbiotic species, there is interesting potential in the controlled cultivation of weakly parasitic fungi for use as biocontrol agents. When strategically inoculated onto cultivated plants, these fungi can provide protection against more aggressive pathogens through the mechanisms described earlier. This approach offers the advantage of being specific, sustainable, and compatible with organic farming principles. Below are some promising species for this application. Table 6 illustrates how appropriately selected strains of fungi traditionally considered pathogens can instead serve as effective biocontrol agents. The success of these approaches depends on a deep understanding of the biology of the species involved, including their virulence, host range, and ecology. For mushroom growers, this opens new possibilities for diversification, with the potential to develop high-value products for sustainable agriculture. In Japan, some shiitake (Lentinula edodes) cultivators deliberately inoculate their logs with weak strains of the parasitic fungus Trichoderma harzianum. This empirically developed practice reduces contamination by more aggressive Trichoderma strains and other competing fungi, increasing final yields by 15–20%. It’s a practical example of how the discussed ecological principles can be applied in commercial mushroom cultivation. Another promising biotechnological application involves using compounds extracted from parasitic fungi to stimulate plant defenses. Known as “elicitors,” these signaling molecules activate plant defense responses without causing significant damage. Exogenous application of elicitors can “prime” plants to better withstand subsequent pathogen attacks, reducing the need for fungicide treatments. Parasitic fungi represent a particularly rich source of elicitors, as they have evolved complex molecular communication systems with their host plants during co-evolution. Among the most studied elicitors are β-glucans and chitin from fungal cell walls, peptides like cryptogein produced by Phytophthora cryptogea, and small molecules such as salicylic acid produced by some pathogenic fungi. These pure or semi-pure compounds can be applied to crops as foliar sprays or root treatments, inducing an “immunized” state that lasts from several weeks to several months. The main advantage of this approach is that it does not exert direct selective pressure on pathogens, thereby reducing the risk of resistance development compared to conventional fungicides. Despite significant advances in understanding the ecological role of parasitic fungi, many questions remain open and require further investigation. Future research will need to integrate traditional plant pathology approaches with advanced genomics, metabolomics, and community ecology techniques to unravel the complexity of these interactions. This final section outlines key research directions and potential applications that could emerge from a deeper understanding of the balance between parasitic fungi and trees. One of the most exciting frontiers in this field is the integration of genomic, transcriptomic, proteomic, and metabolomic data to develop predictive models of plant–parasitic fungus interactions. These models could allow us to more accurately predict the outcome of fungal infections under different environmental conditions, identifying critical points where targeted interventions could prevent epidemic development. For example, integrated analysis of plant and fungal transcriptomes during early infection stages could reveal gene expression patterns predictive of the shift from moderate to severe infection. The main challenge in this approach is data complexity and the need for advanced machine learning algorithms capable of identifying meaningful patterns in multidimensional datasets. Collaborative research projects, such as the “Forest Microbiome Project” launched in 2023, are beginning to collect multi-omics data at ecological scales, opening new possibilities for systemic understanding of forest interactions. Building on acquired knowledge, researchers are beginning to explore the possibility of “engineering” fungal communities to enhance forest resilience to climate change and emerging diseases. This approach, known as “ecological engineering,” deliberately manipulates microbial communities to achieve desirable ecological outcomes, such as greater pathogen resistance or improved drought tolerance. Techniques could include inoculating trees with selected cocktails of weak parasitic fungi, modifying management practices to favor beneficial fungal communities, or creating “microbial corridors” that allow natural spread of protective fungi between fragmented forest areas. A particularly promising application concerns forest regeneration after large-scale disturbances such as fires or storms. By inoculating young plants with balanced fungal communities that include moderate parasites, we could accelerate the development of resilient ecosystems while reducing vulnerability to subsequent epidemics. Pilot projects in this direction are already underway in several European regions affected by Dutch elm disease and ash dieback. A four-year research project launched in 2024 at the University of Bologna is testing the hypothesis that combined inoculations of mycorrhizal and weakly parasitic fungi can synergistically protect trees. Preliminary results on beech seedlings suggest this combination reduces mortality from Phytophthora infections by 89% compared to non-inoculated seedlings, and by 47% compared to seedlings inoculated only with mycorrhizae. If confirmed, these findings could revolutionize forest nursery practices. Through this in-depth analysis, we have explored the ecological paradox of parasitic fungi and their fundamental role in preventing trees from being wiped out by more aggressive pathogens. From molecular mechanisms of competition and metabolite production to forest community dynamics and practical applications in forestry and mushroom cultivation, a coherent and compelling picture emerges: parasitic fungi are not merely disease agents, but essential components of forest ecosystems, performing regulatory and protective functions often underestimated. The main lesson we can draw from this analysis is that forest health depends not on the absence of pathogens, but on the dynamic balance between trees and their associated fungal communities. When this balance is disrupted—whether by poorly conceived human interventions, introduction of exotic pathogens, or climate change—the consequences can be devastating, as demonstrated by Dutch elm disease and ash dieback epidemics. Conversely, forests that maintain adequate fungal diversity, including moderate parasites, show remarkable resilience to both biotic and abiotic stresses. For mycologists, mushroom cultivators, botanists, and all fungi enthusiasts, this understanding offers not only a more nuanced perspective on the fungal kingdom but also practical opportunities to contribute to forest conservation and restoration. Whether it’s selecting trees for tolerance rather than absolute resistance, developing new biocontrol approaches based on weak parasitic fungi, or simply appreciating the complex beauty of ecological interactions, recognizing the value of parasitic fungi represents a fundamental step toward a more harmonious relationship with the natural world. Ultimately, the story of parasitic fungi and trees teaches us a lesson in ecological humility: what at first glance appears to be a problem—a fungus infecting a tree—may in fact be part of the solution to greater threats. In an era of rapid environmental change and growing pressures on forest ecosystems, this lesson may prove more valuable than ever.Parasites and fungi: the great paradox
The role of parasitic fungi in natural biological control
Interspecific competition: the silent war among microorganisms
Tree species “Moderate” parasitic fungus Aggressive pathogen controlled Competition mechanism Infection reduction Quercus robur (oak) Microsphaera alphitoides (powdery mildew) Phytophthora ramorum (sudden oak death) Competition for leaf surface area and production of antifungal metabolites 34–58% (depending on climatic conditions) Picea abies (Norway spruce) Heterobasidion annosum Ips typographus (bark beetle) + associated fungi Early wood colonization and induced production of antifungal resins 41% reduction in mortality Fraxinus excelsior (ash) Armillaria mellea Hymenoscyphus fraxineus (ash dieback) Chemical modification of wood composition and direct competition 22–29% (preliminary data) Ulmus minor (elm) Nectria cinnabarina Ophiostoma novo-ulmi (Dutch elm disease) Production of natural antibiotics (nectrianolines) and niche occupation Up to 67% under controlled humidity conditions Production of secondary metabolites: the fungal chemical arsenal
Compound class Specific examples Producing Fungi Protective Action Effect on Host Trees Terpenoids Trichothecenes, gibberellins Fusarium spp., Gibberella fujikuroi Antibacterial, antifungal, growth regulation 40–60% reduction in secondary bacterial infections Bioactive polysaccharides β-glucans, chitin Numerous basidiomycetes and ascomycetes Induction of plant immune responses (SAR) Activation of defense genes throughout the tree Alkaloids Ergotamine, lolitrem B Claviceps purpurea, Neotyphodium spp. Anti-herbivore, insecticidal Up to 75% reduction in insect defoliation Phenols and quinones Fungal flavonoids, juglone Armillaria spp., numerous lignicolous fungi Antifungal, allelopathic Protection from root infections and limitation of competition Antibiotic peptides Echinocandins, peptaibols Aspergillus spp., Trichoderma spp. Membrane damage to competing fungi 30–80% reduction in fungal pathogen infections
Modulation of microbial communities: fungi as ecosystem engineers
Parasitic fungal species Host plant Microbial groups increased Microbial groups decreased Net effect on plant health Rhizoctonia solani (weak strain) Pinus sylvestris (Scots pine) Pseudomonas fluorescens (+320%), Streptomyces spp. (+180%) Pythium ultimum (-65%), Fusarium oxysporum (-42%) 28% increase in root biomass, 54% reduction in root pathogen infections Phytophthora cinnamomi (low-virulence strain) Quercus ilex (holm oak) Burkholderia spp. (+410%), Trichoderma spp. (+290%) Phytophthora ramorum (-88%), Cylindrocarpon destructans (-76%) 91% reduction in root rot mortality, increased drought tolerance Venturia inaequalis (apple scab – weak strain) Malus domestica (apple) Bacillus subtilis (+550%), Paenibacillus polymyxa (+380%) Erwinia amylovora (-92%), Agrobacterium tumefaciens (-85%) 95% reduction in fire blight infections, increased fruit yield Heterobasidion annosum (slow-growing strain) Picea abies (Norway spruce) Mycorrhizal fungi (+220%), Azospirillum spp. (+190%) Armillaria ostoyae (-77%), Botrytis cinerea (-63%) 68% reduction in collar rot mortality, increased nitrogen uptake Case study: dutch elm disease
Protective Mechanisms Offered by Native Parasitic Fungi
Native parasitic fungus Natural frequency in elms before 1970 Reduction in Ophiostoma colonization Reduction in vector-mediated transmission Increase in elm survival Nectria cinnabarina 82% of adult trees 67% (under controlled lab conditions) 54% (reduced attraction for Scolytus) 7.3× higher 10-year survival probability Botryodiplodia hypodermia 61% of adult trees 49% 38% 4.1× higher survival probability Diplodia ulmi 44% of adult trees 52% 41% 4.8× higher survival probability Phomopsis oblonga 33% of adult trees 38% 29% 3.2× higher survival probability Combination of 2+ species 91% of adult trees 84% 76% 12.7× higher survival probability Implications for forestry in the absence of fungi
Genetic selection for tolerance, not absolute resistance
Selection approach Primary goal Advantages Disadvantages Practical examples Absolute resistance Complete absence of infection No visible damage, maximized short-term production Resistance often overcome within years, loss of ecological benefits, greater vulnerability to secondary pathogens Ash varieties “resistant” to Hymenoscyphus fraxineus (all failed within 10–15 years) Ecological tolerance Coexistence with moderate infections Greater long-term stability, cross-protection benefits, maintenance of associated biodiversity Initial growth reduction (5–15%), harder social acceptance Poplar clones tolerant to Melampsora spp. with 10–20% leaf infection but 70% reduction in Phytophthora infections Multilocus resistance Partial resistance mediated by many genes Hard for pathogens to overcome, compatible with tolerance Complex selection, requires advanced molecular markers Oak varieties with 8 QTLs for resistance to Microsphaera alphitoides Promotion of beneficial microbiome Ability to host protective microbial communities Broad-spectrum protection, adaptability to local conditions Complex heritability, interaction with environmental factors Selection of pines for association with ectomycorrhizal fungi that suppress Heterobasidion annosum Silvicultural practices that favor natural balance
Fungal cultivation and biotechnological applications
Cultivation of parasitic fungi for biocontrol
Fungal species Target plant Controlled pathogen Application method Documented efficacy Cladosporium cladosporioides (strain F-10) Vitis vinifera (grapevine) Plasmopara viticola (downy mildew) Preventive foliar spray (10^6 conidia/ml) 74% reduction in downy mildew incidence under field conditions Phoma exigua (non-toxigenic strain) Solanum tuberosum (potato) Phytophthora infestans (potato late blight) Tuber treatment before planting 68% reduction in foliar infections, 22% yield increase Alternaria alternata (saprophytic strain) Malus domestica (apple) Venturia inaequalis (scab) Dormant branch application 81% reduction in primary lesions, residual effect lasting 2–3 years Fusarium oxysporum (non-pathogenic strain Fo-47) Numerous horticultural species Fusarium oxysporum f. sp. lycopersici (fusarium wilt) Root immersion in microconidia suspension 90% reduction in infections in naturally infested soils Extraction and production of elicitors for plant defense
Future perspectives and research directions
Integration of multi-omics data for predictive models
Ecological engineering for resilient forests
Parasites