Search Results (6)

Mediterranean agroforestry systems (AFSs), typified by the Iberian Dehesas and Portuguese Montados, are multifunctional landscapes where Quercus species act as ecological keystones sustaining biodiversity, soil fertility, and rural livelihoods. These systems are increasingly affected by complex oak decline syndromes driven by drought, soil degradation, and climate-induced pathogen outbreaks. Conventional chemical controls are often ineffective and environmentally detrimental, underscoring the need for ecologically sound management alternatives. This review synthesizes recent advances in the application of microbial biological control agents (MBCAs) to manage diseases in Mediterranean Quercus species, including Q. ilex, Q. suber, Q. faginea, and Q. pyrenaica. We conducted a structured literature review using predefined keyword searches in Web of Science and Scopus, followed by the screening of records to identify 22 relevant peer-reviewed studies on microbial disease control in Mediterranean Quercus species. We identified 20 peer-reviewed studies that reported that MBCAs—primarily from Bacillus, Serratia, Streptomyces, Trichoderma, Simplicillium and Alternaria—exert biocontrol effects through antibiosis, mycoparasitism, competition for ecological niches, and the induction of host defense responses. Although most experiments were conducted in vitro, some demonstrated significant disease suppression in seedlings infected by Phytophthora cinnamomi, Diplodia corticola, and Biscogniauxia mediterranea. Future research should integrate field-based validation and microbiome-oriented forest management approaches to enable the operational use of microbial-based disease control strategies in AFS landscapes. Full article

Sustainable agricultural practices are essential for eradicating global hunger, especially in light of the growing world population. Utilizing natural antagonists, such as fungi and bacteria, to combat plant diseases, rather than relying solely on synthetic chemical pesticides, which pose significant risks to the environment and human health, is known as biocontrol. Microbial biological control agents (MBCAs) have proven effective against phytopathogens and are increasingly embraced in agricultural practices. MBCAs possess several beneficial traits, including antagonistic potential, rhizosphere competence, and the ability to produce lytic enzymes, antibiotics, and toxins. These biocontrol mechanisms directly target soil-borne pathogens or indirectly stimulate a plant-mediated resistance response. The effectiveness of MBCAs in managing plant diseases depends on various mechanisms, such as hyperparasitism, antibiosis, competition for nutrients or space, disruption of quorum-sensing signals, production of siderophores, generation of cell wall-degrading enzymes, and the induction and priming of plant resistance. Formulating effective biopesticides requires optimal conditions, including selecting effective strains, considering biosafety, appropriate storage methods, and ensuring a prolonged shelf life. Therefore, formulation is crucial in developing pesticide products, particularly concerning efficacy and production costs. However, several challenges must be addressed to ensure the successful application of biological control, including the shelf life of biopesticides, slower efficacy in pest management, inadequate awareness and understanding of biocontrol methods, regulatory registration for commercialization, and suitable agricultural applications. This review clarifies the principles of plant disease biocontrol, highlighting the mechanisms of action and functionality of MBCAs in biocontrol activities, the formulation of biopesticides derived from microorganisms, and the challenges and barriers associated with the development, registration, commercialization, and application of biopesticides. Full article

In a world with constant population growth, and in the context of climate change, the need to supply the demand of safe crops has stimulated an interest in ecological products that can increase agricultural productivity. This implies the use of beneficial organisms and natural products to improve crop performance and control pests and diseases, replacing chemical compounds that can affect the environment and human health. Microbial biological control agents (MBCAs) interact with pathogens directly or by inducing a physiological state of resistance in the plant. This involves several mechanisms, like interference with phytohormone pathways and priming defensive compounds. In Argentina, one of the world’s main maize exporters, yield is restricted by several limitations, including foliar diseases such as common rust and northern corn leaf blight (NCLB). Here, we discuss the impact of pathogen infection on important food crops and MBCA interactions with the plant’s immune system, and its biochemical indicators such as phytohormones, reactive oxygen species, phenolic compounds and lytic enzymes, focused mainly on the maize–NCLB pathosystem. MBCA could be integrated into disease management as a mechanism to improve the plant’s inducible defences against foliar diseases. However, there is still much to elucidate regarding plant responses when exposed to hemibiotrophic pathogens. Full article

Endophytic fungi are used as the most common microbial biological control agents (MBCAs) against phytopathogens and are ubiquitous in all plant parts. Most of the fungal species have roles against a variety of plant pathogens. Fungal endophytes provide different services to be used as pathogen control agents, using an important aspect in the form of enhanced plant growth and induced systemic resistance, produce a variety of antifungal secondary metabolites (lipopeptides, antibiotics and enzymes) through colonization, and compete with other pathogenic microorganisms for growth factors (space and nutrients). The purpose of this review is to highlight the biological control potential of fungal species with antifungal properties against different fungal plant pathogens. We focused on the introduction, biology, isolation, identification of endophytic fungi, and their antifungal activity against fungal plant pathogens. The endosymbionts have developed specific genes that exhibited endophytic behavior and demonstrated defensive responses against pathogens such as antibiosis, parasitism, lytic enzyme and competition, siderophore production, and indirect responses by induced systemic resistance (ISR) in the host plant. Finally, different microscopic detection techniques to study microbial interactions (endophytic and pathogenic fungal interactions) in host plants are briefly discussed. Full article

Wheat rust outbreaks have caused significantly economic losses all over the world. Puccinia striiformis f. sp. tritici (Pst) is an obligate biotrophic fungus causing stripe rust on wheat. Application of fungicides may cause environmental problems. The effects of hyperparasites on plant pathogens are the basis for biological control of plant pathogenic fungi and parasites of Pst have great value in biological agents development. Here, we report the isolation and characterization of isolate of Cladosporium cladosporioides from Pst based on morphological characterization and analysis of molecular markers. The hyperparasitic isolate was isolated from taupe-colored uredinia of Pst. Upon artificial inoculation, the hyperparasitic isolate was able to reduce the production and germination rate of Pst urediospores, and Pst uredinia changed color from yellow to taupe. Scanning electron microscopy demonstrated that the strain could efficiently colonize Pst urediospores. Therefore, the isolate has the potential to be developed into a biological control agent for managing wheat stripe rust. Full article

Developing sustainable agriculture by identifying non-chemical alternative Plant Protection Products (PPP) is a cornerstone in achieving long-sought environmental friendliness. Despite significant legislative and political efforts to promote biocontrol solutions and Integrated Pest Management (IPM), the literature points out the disadvantages posed by European Union’s (EU) two-tier system for Microbial Biological Control Agents (MBCA) approval and subsequent Microbial Biological Control Products (MBCP) authorization by each EU Member State (MS). Despite the disadvantages, in a recent article, we showed that the EU had outcompeted the US and other countries in approved MBCA in the last decades; however, MBCP approval at the national level lags. Achieving the EU Green Deal’s aim set out in the ‘Farm to Fork Strategy’ to reduce the use and risk of pesticides by 50% by 2030 is difficult without developing viable alternatives. Why do we not have higher MBCP availability and usage in the EU? Is it the current legislation, its poor application, or some other factors? The current legislative framework stimulated MBCA approval. Thus, we compare MBCA approval and MBCP authorization procedure to evaluate if MBCP authorization is more difficult and thus causes a bottleneck. We find that requirements for MBCP authorization are unnecessarily more complex. We recommend simplifying the MBCP dossier requirements and making them as similar to MBCA as possible to accelerate the MBCP authorization in more EU MS to increase their availability and integration in agronomic crops’ pest management plans. Full article