The fall armyworm (Spodoptera frugiperda) is attacked by multiple egg parasitoid species that may co-exploit the same host resources, leading to interspecific competition that can influence biological control outcomes. Among the most widely used egg parasitoids are Telenomus remus and Trichogramma pretiosum, yet their relative performance under different host egg densities remains poorly understood. We investigated density-dependent competitive interactions between these two parasitoids on fall armyworm eggs under both simultaneous and isolated release conditions. Host egg densities of 15, 30, and 60 eggs were used to assess parasitism rate, sex ratio, developmental time, and intrinsic competition. The relative parasitism success of the two parasitoids varied with host density. Telenomus remus parasitised more hosts at medium and high densities, whereas Tr. pretiosum performed better at low host density. Multiparasitism was detected, but only one parasitoid species completed development within an individual host egg. Embryological observations indicated that intrinsic competition occurred during early embryogenesis, with T. remus embryos frequently undergoing developmental arrest in multiparasitised host eggs. T. remus produced a more female-biased sex ratio, while Tr. pretiosum completed development more rapidly across host densities. These results show that host egg density can mediate competitive outcomes between egg parasitoids and should be considered when evaluating parasitoid species for fall armyworm biological control.
Protection provided by ants to honeydew-producing insects can limit biological control by reducing predator access to pest colonies. Providing artificial sugar sources away from aphid colonies has been proposed as a way to redirect ant foraging from honeydew to alternative carbohydrate resources, but its effectiveness may depend on habitat context and the timing of sugar provisioning. We tested whether sugar diversion weakens ant-mediated protection of the rosy apple aphid, Dysaphis plantaginea, and whether its effect depends on provisioning timing and flower-strip management in apple orchards.Over two growing seasons with contrasting aphid pressure, we manipulated sugar provisioning timing, early, late or none, and flower-strip management, comparing intact and mown flower strips. We followed 5,187 individually identified aphid colonies through 13,303 active colony observations, monitoring aphid colony dynamics, ant attendance, predator abundance, predator access and colony survival.Sugar diversion reduced the probability and intensity of ant attendance, including relative ant attendance after accounting for aphid abundance. Predator abundance was affected by sugar-treatment timing and was highest when sugar diversion was combined with intact flower strips. Predator abundance was lower on ant-attended colonies than on colonies without attending ants, indicating that ant attendance constrained predator access to aphid colonies. Sugar diversion also shifted aphid colony size structure, with sugar-treated plots containing a higher proportion of smaller colonies at peak aphid activity. Colony-survival responses were more variable, but the clearest increase in disappearance risk occurred under late diversion in intact flower-strip plots.Combining sugar diversion with flower-strip management weakened ant-mediated aphid protection and improved conditions for conservation biological control in orchards. Rather than suppressing ants directly, this approach manipulates ant foraging behaviour to reduce interference with natural enemies and may provide a complementary tactic for managing ant-protected aphids in perennial fruit systems.
Picromerus lewisi Scott (Hemiptera: Pentatomidae) is a dominant predatory natural enemy in agroforestry pest management. Although P. lewisi frequently experiences food deprivation during biological control programs, the effects of parental starvation followed by re-feeding on parental reproductive fitness, F1 offspring performance, and predation-related traits remain unclear. We evaluated the effects of 0-, 10-, and 20-d parental starvation followed by re-feeding on P. lewisi using age-stage, two-sex life table analysis, with Ephestia elutella (Hübner) (Lepidoptera: Pyralidae) as prey. Twenty-day starvation markedly reduced fecundity (70.62 and 11.14 eggs in the parental and F1 generations, respectively) and oviposition duration (2.33 and 1.67 days, respectively) in both generations. This treatment also suppressed F1 population growth, with the net reproductive rate (R0), intrinsic rate of increase (r), and finite rate of increase (λ) decreasing to 3.86 individuals, 0.0247 d-1, and 1.0250 d-1, respectively. In the 120-d simulation, the population reached only 111 individuals, whereas the transformation rate (QP = net predation rate [C0]/R0) increased to 12.67. By contrast, 10-d parental starvation increased F1 survival (46.00%) and population growth, producing a simulated population of 1,207 individuals on day 120 while maintaining a low transformation rate of 2.61. These findings suggest that short-term (10-d) parental starvation followed by re-feeding can improve the survival and predation performance of P. lewisi without an evident fitness cost, providing a theoretical and practical basis for mass rearing and field deployment of this predator in biological control.
Wheat crown rot, caused by Fusarium pseudograminearum (Fp), is a devastating soil-borne disease threatening global wheat production. Sustainable biocontrol strategies are urgently needed. This study characterized a antagonistic fungus, Talaromyces assiutensis R-9, and evaluated its mechanisms and biocontrol efficacy against Fp. Dual-culture antagonism assays demonstrated that strain R-9 strongly suppressed radial mycelial growth of Fp, resulting in a 10 mm reduction in pathogen colony radius and a mycelial growth inhibition rate of 55.9 %. The inhibitory effect of its fermentation filtrate on Fp growth was dose- and time-dependent, plateauing at 77.38 % inhibition under 25 % concentration and 72 h of treatment. Additionally, the filtrate induced hyphal and sporular distortion, and increased cell membrane permeability. Physiological assays revealed that the filtrate significantly inhibited key enzymes in Fp’s energy metabolism (hexokinase, pyruvate kinase, and succinate dehydrogenase) and antioxidant defense system (superoxide dismutase, peroxidase, catalase, and glutathione peroxidase). Under pot conditions, seed treatment with the R-9 conidial suspension was able to completely reverse the growth inhibition caused by Fp, restoring plant biomass and antioxidant enzyme activities to healthy levels, while reducing the disease index from 58.67 % to 21.3 %, with a control efficacy of 63.7 % (calculated as: [(disease index of control − disease index of treatment) / disease index of control] × 100). Field trials demonstrated that the application of R-9 significantly promoted wheat growth, increasing the thousand-kernel weight from 44.25 g to 49.54 g. The treatment also markedly suppressed disease development, reducing the incidence from 39.57 % to 19.37 %, the whitehead rate from 15.43 % to 3.84 %, and the disease index from 37.77 % to 17.13 %, which corresponds to a control efficacy of 54.6 %. Notably, R-9 application alone enhanced plant growth without activating oxidative stress markers, indicating a direct growth-promoting effect distinct from induced resistance. These findings demonstrate that T. assiutensis R-9 controls wheat crown rot through a multi-mechanistic action involving antibiosis via disruption of pathogen energy metabolism and antioxidant capacity, coupled with plant growth promotion. This study highlights the potential of R-9 as a promising microbial agent for the integrated and sustainable management of wheat crown rot.
Toxorhynchites larvae are obligate predators and considered as biological control agents against container-breeding Aedes mosquitoes. However, quantitative information on their life history traits, stage-dependent predation dynamics, and lifetime predation capacity remains limited. Here, we reported a Toxorhynchites splendens population collected from Foshan city, China, and provided an integrated assessment of its morphology, life history, and predatory performance against Aedes larvae under laboratory conditions. Field surveys revealed substantial overlap between Tx. splendens and Ae. albopictus larvae in the rural areas. Molecular and morphological analysis confirmed their species identity, though slight geographical morphological variation was observed. No significant differences were observed between males and females in egg hatching time or larval developmental duration. However, females had significantly longer pupal duration and adult lifespan, while males had greater pupal width and wing length. Functional response experiments demonstrated that Tx. splendens predation generally followed a Holling type II functional response, but stable model fitting was not observed for all predator–prey stage combinations, indicating pronounced stage-dependent heterogeneity in predation dynamics. By integrating daily prey consumption derived from stable functional response models with instar-specific developmental durations, we found that the estimated lifetime prey consumption of Tx. splendens increased with initial prey density and was consistently higher for Ae. albopictus than for Ae. aegypti. Our results highlight the importance of developmental stage in shaping predation dynamics of Tx. splendens and provide quantitative insights into the predatory capacity of Tx. splendens under laboratory conditions and its potential contribution to future biological control strategies.
The lesser grain borer, Rhyzopertha dominica, and the rice weevil, Sitophilus oryzae, are two of the most damaging pests of stored rice. Here, we explore Beauveria bassiana (strain: GHA) and Cordyceps fumosorosea (strain: FE9901) as biological control agents of these pests. Both fungal strains were tested individually, in combination, and with diatomaceous earth to determine their combined effects. We found an increase in infectivity when including both diatomaceous earth and B. bassiana, as there was a higher percent of sporulating, mycosed individuals in the presence of diatomaceous earth than without it for both S. oryzae (with: 34.34%, without: 3.84%; P < 0.001) and R. dominica (with: 30.51%; without: 17.05%; P < 0.001). However, the combinations provided no additional control beyond that of diatomaceous earth alone, where both treatments had similar levels of adult mortality (R. dominica: 40–42%; S. oryzae: 78–86%). Combinations of B. bassiana and C. fumosorosea provided no additional control beyond that provided by a single fungal treatment. These results demonstrate that there is some potential for these fungal strains to act as management tools for R. dominica and S. oryzae, but further work is needed to determine whether changes in application rate, formulation, or delivery method can improve their efficacy in stored rice.
Grape root rot caused by Fusarium acuminatum is a major threat to grape production, which currently relies heavily on chemical fungicides for control. From grape rhizosphere soil, we obtained 71 Trichoderma isolates representing seven distinct species. Trichoderma longibrachiatum isolate LT9 was selected based on its broad-spectrum antimicrobial activity, as demonstrated through in vitro antagonism assays and evaluations of volatile organic compound and culture filtrate inhibitory effects. In pot experiments, LT9 pretreatment significantly reduced the incidence and disease index of grapevine root rot, achieving a control efficacy of 80.65 %. This treatment also persistently induced the activity of defense enzymes—peroxidase, polyphenol oxidase, and superoxide dismutase—in the leaves, while reducing malondialdehyde content and increasing soluble sugar levels to enhance plant resistance. Transcriptome sequencing analysis revealed dynamic transcriptional reprogramming triggered by LT9 treatment in grape plants. Under pathogen stress, both LT9 treatment alone and its co-treatment with the pathogen significantly activated pathways related to plant–pathogen interaction, MAPK signaling, plant hormone signal transduction, and biosynthesis of secondary metabolites. Differentially expression gene analysis further identified several key transcription factor families, including AP2/ERF-ERF, MYB, WRKY, bHLH, and NAC, involved in regulating these defense responses. Protein–protein interaction network analysis screened multiple hub genes that played core regulatory roles at different time points. This study systematically elucidates the multi-level mechanisms—pathogen inhibition, induced systemic resistance, and modulation of defense signaling—by which LT9 controls grape root rot, providing a foundation for developing efficient Trichoderma-based biocontrol agents.
Cucumber Fusarium wilt caused by Fusarium oxysporum f. sp. cucumerinum (FOC) severely threatens global cucumber production. Current control strategies face limitations in sustainability and efficacy, highlighting the need for new, cost-effective, and environmentally friendly alternatives. In this study, from a library of 675 fungal isolates, Trichoderma koningiopsis Snef2767, T. asperellum Snef2773, and T. virens Snef2774 exhibited broad-spectrum antagonism against FOC and F. oxysporum f. sp. melonis (FOM). Among them, Trichoderma koningiopsis Snef2767 exhibited the highest in vitro inhibition rates against FOC and FOM, which were 85.32% and 85.66%, respectively. In pot trials, root irrigation with culture filtrate of Snef2767, Snef2773, and Snef2774 reduced disease severity and enhanced plant growth, with biocontrol efficacies of 60.38%, 52.83%, and 39.63%, respectively. Two-year field trials confirmed consistent control efficacy of the three strains, with the control efficacy of Snef2767 being particularly remarkable (55.84%–56.11%). Mechanistically, all three strains inhibited FOC spore germination and mycelial growth via non-volatile metabolites and hyperparasitized FOC hyphae, inducing shrinkage and degradation. Furthermore, Snef2767 primed cucumber resistance by upregulating salicylic acid (SA) pathway genes and jasmonic acid (JA) pathway genes in cucumber roots, while also enhancing antioxidant enzymes. The high efficacy under field conditions and plant growth-promoting ability support the potential of Snef2767 as a sustainable biocontrol agent.
The tomato leaf miner Phthorimaea(Tuta)absoluta is a highly destructive invasive pest of tomato and a continuing driver of insecticide use and resistance in many productions. Microbial biological control agents propose directed tactics fitting with integrated pest management (IPM). Following PRISMA 2020, peer-reviewed studies (2015–2026) evaluating entomopathogenic bacteria (EPB), fungi (EPF), and nematodes (EPN) against P. absoluta were systematically reviewed. Fifty-four unique studies met the inclusion criteria. The primary meta-analysis was restricted to laboratory mortality outcomes and comprised 197 effect-size estimates from 45 independent publications. Log risk ratios were synthesized using a multilevel random-effect model with estimates nested within publications, restricted maximum-likelihood estimation, and study-clustered CR2 robust inference.Microbial treatments significantly increased mortality relative to untreated controls (RR = 13.65, 95 % CI: 9.43–19.78; 95 % prediction interval: 1.45–128.73; I2 = 78.35 %; p < 0.001). he pooled risk ratios were 7.83 for EPB, 16.02 for EPF, and 18.59 for EPN, although differences among microbial-agent groups were not statistically significant (p = 0.109). Pooled risk ratios were 10.22 for early-instar larvae (L1–L2) and 14.09 for late-instar larvae (L3–L4), with the difference between larval-stage groups approaching but not reaching statistical significance (p = 0.053). Exposure or application method significantly moderated treatment efficacy (p = 0.0449), whereas publication year and risk of bias did not. Greenhouse evidence was analysed separately and remained imprecise, while field and screenhouse evidence was too limited for quantitative pooling. Overall, microbial agents showed strong average efficacy against P. absoluta under controlled conditions; however, substantial heterogeneity, wide prediction intervals, and limited field evidence restrict the extent to which these findings can be generalized to operational IPM programs.
Coccinellids (Coleoptera: Coccinellidae) are the primary aphid predators in alfalfa fields in Central Chile. These communities are abundant and diverse, which increases the likelihood of negative interactions; however, such interactions typically decrease when prey is abundant or through spatio-temporal habitat segregation. Throughout the spring and summer, we continuously sampled adult and larval coccinellids across 20 alfalfa fields south of Santiago, Chile, employing three methods: flight-interception traps, sweep nets (foliage), and pitfall traps (ground-dwelling). A total of 45,960 adults and 16,696 larvae from 16 species were collected. Our analysis of spatial and temporal distributions revealed that community compositions differed significantly across sampling methods for both life stages. Specifically, pitfall-trap communities were the most distinct, suggesting clear spatial segregation. Furthermore, species abundance fluctuated over time: some peaked early in the season alongside aphid populations, while others predominated later as prey became scarce. Notably, while foliage captures prevailed during periods of high prey density, a shift toward other habitat occurred as resources declined. These findings suggest that these communities have dynamic habitat preferences that evolve throughout the season.
Impacts of weed biocontrol agents can be spatially and temporally dynamic. Identifying the specific drivers and contexts of variable outcomes in weed biocontrol programs can inform release approaches and integrated weed management plans. Kordyana brasiliensis is a foliar pathogen which is host-specific to the invasive environmental weed Tradescantia fluminensis. Kordyana brasiliensis has been released in New Zealand and Australia as a biocontrol agent of T. fluminensis. Reports of K. brasiliensis impacts on T. fluminensis populations has been limited to observational reports and quantitative studies undertaken in a small number of areas. Additional research was required to evaluate broadscale establishment and impacts of K. brasiliensis on T. fluminensis across broad geographical and temporal scales. A field study was established in eastern Australia releasing K. brasiliensis at 14 sites with dense T. fluminensis infestations across an 800 km latitudinal gradient. Despite rapid broadscale establishment (by 6-months), K. brasiliensis disease levels varied significantly over temporal and spatial gradients and was strongly associated with macroclimate variability. Lower disease incidences were observed with higher maximum temperatures, whereas high disease severity was strongly associated with more rain days. The impacts of K. brasiliensis on T. fluminensis populations varied across climate contexts, with greater declines in weed abundances occurring in warmer areas with more frequent rainfall events. Host weed abundances remained stable in drier areas. Models identifying drivers of agent impacts can be incorporated into weed management planning to identify and prioritise areas for alternative management methods where there is limited likelihood of biocontrol success.
Landscape structure plays a critical role in shaping natural enemy communities and biological control, yet its effects vary across agroecosystems and spatial scales. This study examined how landscape composition influences ladybird beetle (Coccinellidae) communities across rice and orchard systems in subtropical Taiwan, using survey data from 85 plots in thirteen production areas. Coverage-standardized rarefaction indicated comparable species richness in the two systems, but orchards supported significantly higher Shannon and Simpson diversity, showing that the systems differ in evenness rather than in the number of species present; in both, however, a small subset of species accounted for most individuals. Landscape effects on richness were strongly scale-dependent, with paddy communities responding to local extents of 50–100 m and orchard communities to broader contexts of 750–1000 m, and landscape variables explained approximately twice as much variation in orchards as in paddies. Redundancy analysis and two-way PERMANOVA showed that dominant species assemblages differed primarily by cropping system and secondarily by geographic region. Rather than being purely species-specific, these associations fell into three functional strategies: disturbance-tolerant generalists of managed habitats, refuge-dependent secondary species, and woody-habitat fidelity specialists. In paddies, the configuration of ditch networks and the spacing of low-vegetation patches mattered more than the total amount of non-crop habitat. These results reveal a management trade-off: simplified paddy landscapes call for local interventions that augment dominant predators, whereas structurally stable orchard systems are better suited to broad-scale configuration strategies that conserve natural enemy diversity.
Chrysopids are generalist predators widely distributed in agroecosystems and are crucial for the biological control of agricultural pests. However, these natural enemies rarely act alone, coexisting with multiple predator species and engaging in interactions such as competition, behavioral interference, and intraguild predation. Despite increasing recognition of predator-mediated non-consumptive effects, little is known about how chemical cues exchanged among natural enemies influence predator behavior and spatial decisions. Understanding how predators respond to chemical cues from other natural enemies is essential for elucidating the behavioral mechanisms that structure predator communities and influence their spatial organization. In this context, this study investigated how chemical cues from conspecific (Chrysoperla externa) and heterospecific (Coleomegilla maculata) predators affect movement behavior and spatial decision-making in Ch. externa. Two complementary bioassays were conducted. A video-tracking assay quantified changes in movement patterns and space use in a continuous arena, while a Y-tube olfactometer assay evaluated odor-guided spatial choice in a binary-choice context. Chemical cues from Co. maculata affected the initial decision-making process of Ch. externa larvae, reducing both the probability of immediate entry and the time spent in areas associated with this predator, without altering overall locomotor activity. In contrast, larvae showed a clear preference for conspecific cues and avoided heterospecific odors, indicating the ability to discriminate among different chemical stimuli. Overall, heterospecific chemical cues induced avoidance responses, whereas conspecific cues were associated with attraction. These findings support the hypothesis that predator-associated chemical cues mediate non-consumptive behavioral responses, contributing to the spatial organization of predator communities and potentially influencing the dynamics of biological control in agroecosystems.
Botrytis cinerea causes severe yield losses in global tomato production. Chemical control faces limitations due to resistance development and environmental concerns, necessitating sustainable alternatives. This study aims to evaluate antimicrobial-spectrum and biocontrol potential of Streptomyces murinus 2LS4 against tomato gray mold, its impact on plant physiology, and genomic basis of its activity. Antifungal activity was assessed using plate confrontation assays, poisoned plate method and spore germination assays. Control efficacy was evaluated on detached tomato leaves and fruits. Disease-resistance-related physiological and biochemical indicators of treated tomato plants were measured. Whole-genome sequencing and comparative genomics identified functional genes. Strain 2LS4 inhibited 16 plant pathogens by over 65 %, suppressing B. cinerea by 97.22 %. Treatment with its 50 % fermentation broth, supernatant, and sterilized supernatant reduced B. cinerea spore germination to 13.92 %, 3.36 %, and 7.21 %, respectively. Fermentation broth and 50 % supernatant showed 68.70 % control efficacy on detached leaves, and 65.39 % and 61.53 % efficacy on detached fruits. Treated plants exhibited significantly increased chlorophyll content (e.g., Chl a: 7.85 mg/L vs 4.03 mg/L), catalase (562.38 U/g vs 468.31 U/g), peroxidase (5.71 U/g vs 3.21 U/g), and soluble sugars (52.76 mg/g vs 45.59 mg/g), while malondialdehyde (8.75 μmol/g vs 10.94 μmol/g) and proline (87.33 μg/g vs 254.85 μg/g) decreased. Genomic analysis revealed 35 secondary metabolite clusters including pentamycin (100 % similarity), chitinases, and siderophores. Comparative genomics showed 98.96 % ANI with S. murinus CR43. S. murinus 2LS4 demonstrates biocontrol potential against tomato gray mold through direct antagonism and plant resistance induction, supported by genomic evidence.
Tomato production and postharvest preservation are severely challenged by gray mold disease caused by Botrytis cinerea. The effectiveness of biocontrol agents against this pathogen is often constrained by their poor environmental stability and low foliar adhesion to plant surfaces. To address these limitations, this study developed a functionally enhanced microcapsule system by chemically grafting sodium alginate with polyacrylic acids (SA-PAAs) for protecting biocontrol bacterium B. amyloliquefaciens W26. The optimized W26@SA-PAAs microcapsules exhibited a high encapsulation efficiency of 86.1 %, superior storage stability (maintaining 78.8 % viability after 160 days at room temperature), and enhanced resilience to heat and UV radiation. Furthermore, this formulation displayed intelligent pH-responsive release behavior, with a maximum release of 86.0 % at pH 7.0 within 10 h, and significantly improved foliar adhesion, retaining 85.2 % of retention. Application of W26@SA-PAAs dramatically reduced the disease rate and disease index in tomato seedlings by 93.38 % and 96.44 %, respectively. This protective effect was associated with elevated activities of defense-related enzymes (SOD and POD), The use of W26@SA-PAAs also resulted in a 50 % reduction in postharvest fruit decay. These results indicate that the W26@SA-PAAs microcapsules effectively enhanced the stability and functional performance of B. amyloliquefaciens W26, offering a highly efficient and environmentally sustainable strategy for plant managing plant diseases and extending postharvest shelf life.
Low-temperature storage (LTS) can extend the shelf life of natural enemies and improve deployment flexibility. This study evaluated the effects of temperature, food source, and insect stage on the survival of Tytthus chinensis during LTS, and further assessed the impacts of optimized storage conditions on adult longevity, predation, cryoprotectant accumulation, and enzyme activities. Under a fluctuating thermal regime (20 h at 10 ℃ followed by 4 h at 25 ℃) with 10% honey solution supplementation, female adult survival remained above 90% after 15 days of storage. This regime significantly prolonged longevity without significantly affecting predation capacity. Under the fluctuating thermal regime (20 h at 10 ℃ followed by 4 h at 25 ℃), female T. chinensis exhibited increases in glucose, trehalose, fructose, and glycerol contents by 67.3%, 100.9%, 45.6%, and 36.2%, respectively, accompanied by elevated lactate dehydrogenase (LDH) and superoxide dismutase (SOD) activities (27.6% and 51.2%), whereas total protein content and Na+-K+-ATPase activity decreased by 25.7% and 69.7%, respectively, compared with 25 ℃. In males, fructose and glycogen contents decreased by 14.5% and 50.0%, respectively, while total protein, catalase (CAT), and SOD activities increased by 30.9%, 17.6%, and 22.9%, respectively; Na+-K+-ATPase activity declined by 51.2%. These findings demonstrate that LTS has considerable potential for T. chinensis mass rearing, particularly for synchronizing mass production with field release demands. To prolong longevity while minimizing quality deterioration, adult T. chinensis should be stored under the fluctuating regime of 20 h at 10 ℃ and 4 h at 25 ℃ with supplementation of 10% honey solution.
The potential of antagonistic isolates was evaluated against the Sclerotium rolfsii and Rhizoctonia bataticola under glasshouse conditions over two seasons. In vitro blotter paper assay against R. bataticola revealed that three isolates (BWA01, RCA08 and RSA02) resulted in no root infection or disease symptoms, while three other isolates (BSA33, RCA5 and BSA17) decreased root infection to < 10% compared to 100% in control. In in vivo biocontrol studies (for two seasons/runs), isolates RSPF04 and BWA01 reduced the S. rolfsii incidence to below 20%, while RCA08 showed lowest disease incidence of 23.4% against R. bataticola. The key antagonistic actinomycetes were identified as Streptomyces spp. except isolate BWA01 as Nesterenkonia aethiopica and bacterial strains as Pseudomonas spp. through 16 s rRNA sequencing. Further, all the synergistic isolates were constructed into six synthetic communities (SynComs) and tested for their efficacy against both the pathogens, S. rolfsii and R. bataticola. SC-6 (SynCom with all potential isolates) treatment led to less prominent symptoms and significantly reduced the disease incidence up to 100% against both the pathogens. The remaining SynComs also significantly reduced the disease incidence. Our findings demonstrate the successful selection of antagonistic microbes including novel species like Nesterenkonia aethiopica and establish that their synergistic application in SynComs confers robust, reproducible protection against soil-borne fungal pathogens in chickpea.
Despite being one of the most economically important forest diseases in the Northern Hemisphere, the dynamics of Heterobasidion root rot in birch (Betula pendula) following thinning remain poorly understood. Assessing infection risk is becoming more relevant as birch gains importance in Fennoscandian forest management. This study examined (1) the incidence and severity of primary Heterobasidion infection of birch stumps following thinning across six stands in southern Sweden, (2) the efficacy of two biological stump treatments, Rotstop®S (Phlebiopsis gigantea) and Basinox® (Pseudomonas protegens), in reducing infection, and prompted by the high colonization of birch stump discs by Ophiostoma quercus, (3) in vitro interactions between O. quercus and Heterobasidion spp. on agar, and among O. quercus, P. gigantea, P. protegens and Heterobasidion spp. on wood. Overall, Heterobasidion incidence was low (0–6%), occurring exclusively on untreated control stumps; no infections were observed in treated stumps. While O. quercus was frequently detected, it did not exhibit consistent antagonistic effects against Heterobasidion spp. on agar, and responses on colonized wood pairings were variable. In contrast, P. gigantea consistently prevented Heterobasidion establishment on colonized wood, while P. protegens also reduced Heterobasidion growth in most cases, although less consistently. These findings indicate that primary Heterobasidion infection on birch following thinning is infrequent and limited in extent. Biological stump treatments were effective under the conditions tested, and given the low treatment cost, a proactive management approach may seem prudent.
Spodoptera frugiperda (J.E. Smith) (Lepidoptera: Noctuidae), the fall armyworm (FAW) is a highly destructive, polyphagous pest that significantly reduces the yield of graminaceous crops including maize in tropical and subtropical regions. The widespread use of synthetic pesticides has led to resistance development, disruption of natural enemies and problems with food safety and environment, highlighting the need for biologically driven control approaches. Microbial entomopathogens such as entomopathogenic nematodes (EPN), entomopathogenic fungi (EPF), entomopathogenic bacteria (EPB) and entomopathogenic viruses (EPV) are crucial components of sustainable FAW management. This review presents global information on the virulence, persistence, and pathogenicity of the major microbial control agents, including Heterorhabditis, Steinernema spp., Bacillus thuringiensis, Beauveria bassiana, Metarhizium anisopliae, and Spodoptera frugiperda multiple nucleopolyhedrovirus (SfMNPV), in laboratory, semi-field, and field settings. Particular emphasis is given to the comparative study of infection biology, stage-specific efficacy, formulation, and delivery systems, and their performance across different agro-ecological zones. This study critically examines new information on endophytic colonization by EPF, the relative safety of microbial agents to natural enemies, and their synergistic interactions with other integrated pest management (IPM) components. Restrictions pertaining to mass production, resistance risk, abiotic stress tolerance, targeting of hidden feeding places, and marketing are thoroughly investigated, particularly in smallholder farming systems. By fusing mechanistic, ecological, and operational viewpoint, this review offers a framework for selecting and combining entomopathogens, refining formulations and application techniques, and expanding their use within IPM programs for the sustainable control of S. frugiperda.
Strawberry anthracnose caused byColletotrichum spp.leads to substantial yield losses, and biocontrol usingBacillus velezensisTCS001 offers a promising alternative to chemical fungicides. However, the colonization dynamics, duration of induced resistance, and underlying molecular mechanisms remain unclear. In this study, we constructed a GFP-tagged strain TCS001-GFP, which exhibited growth characteristics and antifungal activity comparable to the wild-type strain. Root drenching with TCS001-GFP resulted in rapid colonization of strawberry roots (peak 8.7 × 10⁶ CFU/g at day 3), leaves (peak 2.1 × 10⁶ CFU/g at day 7), and petioles (peak 1.6 × 105 CFU/g at day 5), with stable populations persisting for at least 35 days. TCS001 significantly promoted plant growth, increasing plant height (92.2 %), shoot fresh weight (132.5 %), root fresh weight (317.8 %), and leaf number, accompanied by elevated levels of indole-3-acetic acid (67.5 %), gibberellic acid (7.0 %), and abscisic acid (38.3 %). The bacterium induced systemic resistance againstC. siamense, providing strong protection (control efficacy > 92 %) when challenged within 3 days after treatment, but efficacy declined to 9.6 % by day 21. Transcriptome analysis revealed that TCS001 downregulated photosynthesis-related genes while upregulating defense-related genes involved in MAPK signaling, phenylpropanoid biosynthesis, and glutathione metabolism. Time-course qPCR of seven defense-related genes (WRKY23,RPV1,PR-1,PR-1A-like,PR-4-like,NBS-LRR,cytochrome P450) uncovered a coordinated temporal activation indicative of a systemic defense strategy. Collectively, our findings demonstrate that TCS001 colonizes strawberry plants systemically, promotes growth through phytohormone modulation, and induces transient resistance via transcriptional reprogramming. The relatively short protection window highlights the need for optimized application strategies to maximize its biocontrol potential in sustainable strawberry production.
