Search Results (442)

Agricultural intensification has weakened natural pest regulation by reducing habitat resources for natural enemies and limiting plant-mediated resistance. Here, we conducted field experiments during 2024–2025 to evaluate the combined effects of Cnidium monnieri field-margin planting and maize seeds coated with the endophytic fungal strains YC (Beauveria bassiana) and PL (Purpureocillium lilacinum) on predator conservation, pest suppression, and biological control in maize agroecosystems. Compared with natural grass margins, C. monnieri significantly increased predator abundance, species richness, and Shannon diversity, particularly of ladybirds, minute pirate bugs, and spiders (p < 0.05). Gut-content analysis detected C. monnieri DNA in ladybirds collected 10–40 m from field margins, confirming predator resource use and spillover into maize fields. Importantly, endophytic fungus-coated seeds did not reduce predator abundance or diversity. Moreover, combining C. monnieri with endophytic fungi enhanced pest suppression and achieved control efficacy comparable to imidacloprid (p > 0.05). These findings demonstrate that integrating functional plants with endophytic fungi simultaneously strengthens top-down biological control and endophyte-associated bottom-up pest suppression, providing an effective and environmentally sustainable strategy for pest management in maize. Full article

Entomopathogenic fungi such as Beauveria bassiana are important biological control agents that provide alternatives to chemical insecticides; however, their application is often limited by relatively slow killing rates. In this study, we engineered the B. bassiana Bb2860 strain to express the spider-derived neurotoxin gene Hv1a and evaluated the biological characteristics and insecticidal activity of the recombinant strain. Bb2860-Hv1a was constructed using a blastospore-mediated LiAc/PEG transformation system and confirmed by PCR and Western blot analyses. Re-isolated recombinant fungi retained detectable Hv1a expression following host infection. Hv1a expression did not affect colony growth or conidial production under laboratory conditions. Bioassays using different infection approaches showed that the effects of Hv1a expression varied among insect species and experimental conditions. Bb2860-Hv1a did not significantly enhance insecticidal activity against G. mellonella, Spodoptera litura, or Ostrinia furnacalis larvae in immersion assays, but shortened the LT₅₀ of O. furnacalis larvae from 5.20 to 4.15 days in hemocoel injection assays. Foliar spray assays showed enhanced mortality of Bb2860-Hv1a compared with the wild type against Aphis gossypii, Myzus persicae, Frankliniella occidentalis, and Bemisia tabaci, with final mortality rates of 62.22%, 68.89%, 60.00%, and 95.56%, respectively, and LT₅₀ values of 4.86, 5.61, 5.92, and 4.87 days. Collectively, these results indicate that Hv1a expression can enhance the insecticidal activity of B. bassiana under specific bioassay conditions, particularly against several piercing–sucking pests evaluated by spray application. This study provides a basis for further evaluation and optimization of Hv1a-expressing B. bassiana as a potential fungal biocontrol candidate. Full article

Entomopathogenic fungi (EPF) are important microbial agents for sustainable pest management. However, their effectiveness depends on compatible formulations that preserve conidial viability and biological activity. Hirsutella citriformis Speare produces an extracellular gum with potential application as a microbial formulation component. The present study evaluated its short-term compatibility with Beauveria bassiana (Balsamo) Vuillemin and Metarhizium brunneum (Petch) conidia, together with mortality associated with gum-based treatments against Bactericera cockerelli (Šulc), under greenhouse conditions. Conidia were formulated in 0.5% (w/v) gum and applied at 1 × 10⁷ conidia mL⁻¹. Conidial germination remained above 90% and was not affected by gum exposure. Significant treatment effects on mortality were detected for adults and nymphs, using binomial generalized linear models. B. bassiana formulation produced 75.0% and 93.56%, whereas M. brunneum produced 65.2% and 78.2% adult and nymph mortality, respectively. The gum-containing treatment, which included Tween 80, was associated with 44.9% adult and 63.0% nymph mortality. H. citriformis gum therefore showed short-term compatibility with both fungi. However, because we did not include a Tween alone control, mortality may not be specifically attributed to the gum. Further studies will evaluate the basis of this mortality and formulation performance, under storage and field conditions. Full article

20-Hydroxyecdysone (20E) is the active form of the steroid hormone ecdysone and is responsible for regulating insect development, molting, and metamorphosis. Infection with the entomopathogenic Beauveria bassiana enhances innate immunity and reduces 20E titers in Lymantria dispar. To further explore the role of the 20E signaling pathway in antifungal immunity, we combined exogenous hormone assays, proteomic profiling, and RNAi-mediated knockdown. In this study, exogenous hormone assays revealed that 20E accelerated the death of B. bassiana-infected larvae, whereas juvenile hormone (JH) markedly delayed it. 20E promoted larval weight gain and food utilization efficiency in L. dispar during fungal infection compared to the B. bassiana group. Moreover, the 20E + B. bassiana group significantly decreased the expression of the Toll pathway-related genes, Attacin2, Gloverin4, and Lysozyme4, while reducing hemocyte counts and Pvf2 expression. Furthermore, the 20E + B. bassiana group increased the number of hyphae in the hemolymph, but had no obvious effect on hemocyte encapsulation capacity compared to the B. bassiana group. Proteomic analysis showed that Cyp306a1 and Cyp314a1 were significantly down-regulated in L. dispar at 48 h post-infection with B. bassiana. Knockdown of Cyp306a1 delayed molting and increased larval mortality in L. dispar, but did not alter the mortality rate upon B. bassiana infection compared to the dsGFP group. Intriguingly, dsCyp306a1 + B. bassiana group had significantly increased the expression of Toll3, Toll5, Toll7, Gloverin4 and Cecropin5 compared to the B. bassiana group. In conclusion, these findings suggest that reduced 20E signaling shifts L. dispar from growth toward immune activation during B. bassiana infection. This study provides valuable insights into the 20E-mediated trade-off between growth and immunity. Full article

Pine wilt disease, caused by Bursaphelenchus xylophilus and vectored by Monochamus alternatus, is a devastating forest disease. The parasitoid Sclerodermus guani and entomopathogenic fungus Beauveria bassiana are effective biocontrol agents against wood-boring pests, but their compatibility remains poorly understood. We exposed adult female S. guani to three concentrations of B. bassiana conidia (1 × 10⁵, 1 × 10⁶, and 1 × 10⁷ conidia mL⁻¹) and assessed parasitoid mortality, infection, reproduction, and parasitism capacity against M. alternatus larvae. Mortality and infection rates increased significantly with concentration and exposure time. At 30 days post-exposure, corrected mortalities were 72.47%, 91.30%, and 100% for the three concentrations, respectively. Time–dose–mortality analysis yielded LT₅₀ values of 27.69, 20.00, and 5.92 days, confirming faster kill at higher doses. Fungal exposure reduced offspring production and development at high concentrations, yet fungus-carrying females still successfully parasitized M. alternatus. Importantly, low fungal concentrations caused only minor reductions in parasitism success and offspring survival. These findings demonstrate that the compatibility between B. bassiana and S. guani is strongly concentration-dependent. Therefore, optimizing fungal dosage is essential to balance fungal dispersal and parasitoid fitness in fungus-carrying biocontrol systems. Our study provides valuable insights into ecological interactions between entomopathogenic fungi and parasitoids, facilitating integrated pest management strategies for wood-boring pests. Full article

The fall armyworm (FAW), Spodoptera frugiperda, is a highly polyphagous pest that has rapidly expanded across Africa, Asia, and Oceania, threatening food security and agricultural productivity. Reliance on synthetic insecticides for FAW management is increasingly challenged by insecticide resistance, environmental contamination, and adverse effects on non-target organisms and human health. This review synthesizes current knowledge on the potential of endophytic fungi as a sustainable strategy for FAW management. Following a systematic literature search, 59 original research articles published over the past 41 years were evaluated. These studies investigated 44 fungal species across 37 host crops, with Zea mays representing the most extensively studied system. The fungal species most frequently assessed were Beauveria bassiana, Metarhizium anisopliae sensu lato (s.l.), and Epichloe coenophialum. Overall, several fungal species successfully colonized plant tissues and reduced FAW performance through increased larval mortality, delayed development, and reduced feeding. These effects were associated with the production of bioactive secondary metabolites, induction of plant defense responses, and alteration of volatile organic compound emissions. Despite these promising findings, important knowledge gaps remain. Studies assessing effects on non-target organisms and natural enemies are scarce, and field validation remains limited. Research efforts are also geographically biased, with relatively few studies conducted in Africa despite the continent experiencing some of the highest FAW-related losses. Future research should prioritize field evaluations, multitrophic interaction studies, investigations in underrepresented regions, and socio-economic analyses to support farmer adoption. Addressing these gaps will be critical for determining the practical role of endophytic fungi in sustainable FAW management. Full article

Entomopathogenic fungi of the genus Metarhizium can degrade and penetrate the insect cuticle through the coordinated action of hydrolytic enzymes, mainly lipases, proteases, and chitinases, whose production varies according to the fungal species and fermentation conditions. These enzymes can be generated via submerged fermentation and subsequently employed to enhance the insecticidal activity of fungal conidia. This study aimed to increase protease production from Metarhizium robertsii Mt015 to strengthen biological control agents based solely on fungal biomass. The culture medium composition and physicochemical parameters were optimized using a statistical design approach. Biological activity assays were then performed using Tuta absoluta larvae as the target insect and Beauveria bassiana as the reference control, tested both alone and in combination with the protease extract. Optimization identified wheat bran, casein, and an initial pH of 8–10 as the most influential variables, achieving a 5.5-fold increase in protease activity compared to the basal medium. When the protease extract was combined with B. bassiana conidia, the mortality rate reached 78.2%, significantly higher than the 55.6% achieved with B. bassiana conidia alone. Bliss independence analysis indicated that the observed larval mortality exceeded the additive expectation (Δ = 23.3 percentage points; 95% CI: 16.7–30.0), supporting a synergistic interaction between B. bassiana and the protease extract at 0.68 U/mL. These results demonstrate that enzymatic supplementation markedly improves the insecticidal performance of entomopathogenic fungi, supporting the use of enzyme-enriched formulations as a complementary strategy to strengthen biological control agents and advance the development of next-generation biopesticides. Full article

The ecological adaptations of insect pests, such as multi-niche colonization and physiological resistance to conventional chemicals, pose severe challenges to the sustainable production of sweet potato (Ipomoea batatas). The tobacco whitefly, Bemisia tabaci (Hemiptera: Aleyrodidae), and the sweet potato weevil, Cylas formicarius (Coleoptera: Brentidae), form a highly destructive, spatially separated pest complex. In this study, we evaluated the dual-niche pathogenicity of a Beauveria bassiana (Hypocreales: Cordycipitaceae) isolate, BbCF-2, generated via spaceflight mutagenesis, against C. formicarius and B. tabaci under controlled laboratory conditions. The mutated strain exhibited enhanced colony expansion and a high sporulation capacity (2.72 × 10⁸ conidia/mL). Bioassays revealed that BbCF-2 possesses significantly increased virulence compared to the wild-type strain, capable of overcoming the distinct physiological and physical barriers of both targeted pests. Against the highly sclerotized subterranean C. formicarius adults, BbCF-2 achieved 92.68% mortality at 15 days post-inoculation at 1 × 10⁸ conidia/mL, with an LC50 of 8.452 × 10³ conidia/mL and an LT50 of 6.305 days. Concurrently, against the canopy-dwelling B. tabaci, the isolate demonstrated rapid lethal mycosis with an LT50 of 6.718 days, effectively reducing the adult vector population prior to their typical dispersal timeframe. These results demonstrate that the spaceflight-mutated BbCF-2 strain exhibits broad pathogenicity. By simultaneously targeting both foliar and soil-dwelling pests, this single-agent biological control strategy shows potential for integrated pest management, pending greenhouse and field evaluation. Full article

Fusarium oxysporum f. sp. lycopersici (Fol) is a destructive soil-borne pathogen responsible for major global losses in tomato production, within a context of increasingly constrained fungicide use in intensive farming systems. Sustainable alternatives to chemical fungicides are urgently needed, and microbial secondary metabolites represent a promising source of antifungal compounds. This study explores the antifungal potential of secondary metabolites produced by a natural isolate of Beauveria bassiana (Bb758) previously reported to exhibit strong biocontrol activity against Fol. LC-HRMS metabolomic profiling revealed a chemically diverse metabolite profile dominated by amino acid-derived compounds, peptides and alkaloids. Purification of the crude extract by column chromatography and reverse-phase HPLC yielded beauvericin and several 2,5-diketopiperazines as the main bioactive constituents. These compounds were identified by NMR and LC-HRMS analyses. The antifungal activity of beauvericin (BEA), cyclo(l-Phe-l-Pro) (CFP) and fractions was evaluated against spore germination and germ tube development of Fol. BEA exhibited dose-dependent but limited activity, showing significant inhibition only at high concentrations (100 μg mL⁻¹). In contrast, CFP showed significantly higher antifungal activity than BEA, inhibiting both germination and germ tube formation at concentrations as low as 10 μg mL⁻¹. These results identify CFP as a promising antifungal compound targeting the early infection stages of Fol and highlight fungal-derived diketopiperazines as candidate molecules for sustainable disease management strategies. Full article

Insects are continuously exposed to diverse microorganisms, including symbionts and pathogens, and rely on pattern-recognition receptors (PRRs) to initiate innate immune responses. Gram-negative bacteria-binding proteins (GNBPs) constitute an important class of the pivotal PRRs in insect immunity. However, whether GNBPs participate in immune responses against taxonomically distinct pathogens remains poorly understood. Red palm weevil (RPW), Rhynchophorus ferrugineus, is a notorious stem-boring insect pest that has caused huge economic loss worldwide. Our preliminary data indicated that the expression of RfGNBP5 could be induced dramatically upon the challenge of non-entomopathogenic bacteria Escherichia coli, Staphylococcus aureus and entomopathogenic fungus Beauveria bassiana. Here, it has been found that RfGNBP5 only possesses two conserved domains, a signal peptide and an intact glycoside hydrolase 16 (GH16) domain, but without the canonical carbohydrate-binding module (CBM39), implying that it might mediate insect immunity via its hydrolytic activity. RT-qPCR revealed that RfGNBP5 was expressed at the highest level in the hemolymph compared with other tissues and was significantly upregulated after exposure to pathogens, such as Escherichia coli, Staphylococcus aureus and Beauveria bassiana. Furthermore, the knockdown of RfGNBP5 potentiated the clearance efficiency of hemolymph against the invading pathogenic bacteria and fungi by increasing the expression level of two antimicrobial peptide genes, including RfAttacin in fat body and RfColeoptericin in gut, and augmenting the phenoloxidase (PO) activity in hemolymph. Taken together, these results suggested that RfGNBP5 acts as a negative regulator of RPW immunity, and it might be a potential candidate for further evaluation in RNAi-based pest management. Full article

Beauveria bassiana (Balsamo-Crivelli) Vuillemin can colonize plant tissues as an endophyte, promoting plant growth and defense against pathogens and insect herbivory. Understanding the endophytic behavior of native isolates is important for developing pest management strategies in maize, a crop affected by Spodoptera frugiperda (J. E. Smith). This study aimed to genetically characterize a Mexican B. bassiana isolate (Bb-IIAF1-24) collected in Los Reyes, Michoacán, using the β-tubulin gene. The phylogenetic relationships showed that this isolate formed a well-supported clade with other B. bassiana isolates from different countries; however, a low divergence among them was observed. In a second part of this study, the influence of foliar and soil inoculation (1 × 10⁸ conidia mL⁻¹) of Bb-IIAF1-24 isolate on endophytic colonization in maize plants, as well as the effects on plant growth and herbivory by S. frugiperda were evaluated. This fungus was detected in roots, stems, and leaves, but no significant differences were found between root and stem colonization or between foliar and soil inoculation methods. Beauveria bassiana treatment resulted in increased stem diameter in plants when applied to soil compared to foliar application and the control. In contrast, plants subjected to foliar application were significantly taller than those receiving soil application or the control plants. Plants from both application methods experienced lower leaf damage compared to the control. These findings demonstrate the potential of the Bb-IIAF1-24 isolate as an endophytic fungus to promote maize growth and reduce herbivory by S. frugiperda. Full article

The whitefly (Bemisia tabaci) is a significant pest of chili crops, and the continuous use of insecticides to control it has led to insecticide resistance. This study aimed to characterize and evaluate the pathogenicity and virulence of native entomopathogenic fungus (EPF) strains from the Sotavento region against whiteflies in the laboratory. Fungi were isolated from whiteflies collected from chili plants in different habitats and identified through morphological and molecular characterization. The pathogenicity of nine EPF strains was assessed at 1 × 10⁹ spores mL⁻¹, while the virulence of the most pathogenic strains was evaluated from 1 × 10⁴ to 1 × 10⁹ spores mL⁻¹. The lethal concentration (LC₅₀) and lethal time (LT₅₀) were also determined. Two native genera of EPF were identified: Beauveria and Cordyceps. The strains JV01 and PV02 (Cordyceps javanica), SV01 (Cordyceps fumosorosea), and MV03 (Beauveria bassiana) demonstrated high pathogenicity, causing mortality rates ranging from 94% to 100% at a concentration of 1 × 10⁶ spores mL⁻¹, five days after application. The strains JV01 and SV01 showed LC₅₀ values of 1.65 × 10⁵ and 5.53 × 10⁵ spores mL⁻¹, respectively, with an LT₅₀ of 2 days for both. In conclusion, highly pathogenic and virulent native EPF strains were identified against adult whiteflies on serrano chili. Full article

Root-knot nematode (Meloidogyne incognita) is a significant challenge in cucumber (Cucumis sativus L.) production under protected cultivation systems. This study aimed to evaluate the effects of four microbial biocontrol agents (Trichoderma asperellum, Beauveria bassiana, Fusarium proliferatum, and Bacillus mojavensis) on cucumber growth and root gall formation. Two greenhouse experiments (spring and summer 2023) were conducted using potted plants inoculated with 100 g of nematode-infected soil. All treatments improved seed germination compared with the untreated control, particularly B. mojavensis and T. asperellum. During vegetative growth, F. proliferatum and B. mojavensis produced higher biomass in the spring experiment, while T. asperellum enhanced root development. Treatment with T. asperellum reduced root galling by 45% in the spring and 31% in the summer experiment, although these differences were not statistically significant. In the chemotaxis assay, the different microbial biocontrol agents showed variation in the chemotaxis index (CI), ranging from 0 to 0.12 among treatments. Overall, microbial treatments mainly enhanced plant growth under nematode stress, while effects on root galling were limited. Full article

The invasive tomato leafminer, Tuta absoluta, poses a severe global threat to solanaceous crops, necessitating sustainable biocontrol solutions. Through systematic bioprospecting across several Moroccan soils, we constructed a novel library of indigenous fungal isolates using complementary Tenebrio molitor baiting and selective media methods. High-throughput phenotyping identified 49 highly pathogenic isolates, which were characterized for conidial production, thermotolerance, and virulence against T. absoluta. We discovered two lead isolates, Beauveria bassiana UCA-350 and Metarhizium robertsii UCA-329, that demonstrated superior virulence, reducing median survival time and achieving lower LC₅₀ values than most commercial reference strains. Notably, virulence was positively correlated with in vitro conidial yield, revealing a key trait linkage for strain selection. Furthermore, genus-level divergence in thermotolerance was observed, with Beauveria isolates exhibiting significantly higher heat resilience. Our integrated multi-trait screening pipeline not only delivers two potent, regionally sourced biocontrol candidates but also establishes a phenotypic selection framework that prioritizes both efficacy and production scalability, advancing the rational development of next-generation mycoinsecticides. Full article

To identify novel field control strategies against Pyrrhalta aenescens (Coleoptera: Chrysomelidae) and provide scientific support for its biocontrol in urban tree management, this study investigated the virulence of Beauveria bassiana against this pest under laboratory conditions, as well as its physiological and biochemical effects. Bioassays using the dipping method showed that B. bassiana was pathogenic to all developmental stages of P. aenescens, with the highest virulence observed against early-instar larvae (1st and 2nd instars). For these stages, corrected mortality and mycosis rate were positively correlated with conidial concentration, and the median lethal time (LT₅₀) was the shortest. In contrast, pupae and eggs exhibited the strongest resistance to fungal infection. In leaf-disk choice tests, larvae significantly preferred untreated leaves or those treated with low concentrations of B. bassiana, displaying a concentration-dependent repellent response to the fungus. Physiological measurements revealed that larval body length and weight gain were significantly inhibited following fungal exposure. Further analysis indicated that B. bassiana infection markedly reduced total hemocyte counts and triggered intense melanization and nodulation responses, particularly in younger larvae. Overall, these results suggest that B. bassiana has strong potential for the biological control of P. aenescens. Control measures targeting early-instar larvae are recommended for cost-effective management, providing a scientific basis for developing eco-friendly control technologies based on this entomopathogenic fungus. Full article