Search Results (275)

Chrysanthemum morifolium Ramat. is a major ornamental crop that suffers from diverse fungal, bacterial, viral, and insect pests, causing significant yield and quality losses. Between 2015 and 2025, rapid progress in molecular biology, genomics, and ecological regulation has advanced both fundamental research and applied control strategies. Multi-locus sequencing, multiplex PCR, and next-generation sequencing refined the identification of fungal and bacterial pathogens, while functional studies of WRKY, MYB, and NAC transcription factors revealed key resistance modules. Hormone-mediated signaling pathways, particularly those of salicylic acid, jasmonic acid, and abscisic acid, were shown to play central roles in host defense. Despite these advances, durable genetic resistance against bacterial pathogens and broad-spectrum defense against viruses remains limited. Novel technologies, including virus-free propagation, RNA interference, and spray-induced gene silencing, have shown promising outcomes. For insect pests, studies clarified the damage and virus-vectoring roles of aphids and thrips, and resistance traits linked to trichomes, terpenoids, and lignin have been identified. Biocontrol agents such as Trichoderma spp., Bacillus spp., predatory mites, and entomopathogenic fungi have also demonstrated efficacy. Future efforts should integrate molecular breeding, genome editing, RNA-based tools, and microbiome management to achieve sustainable chrysanthemum protection. Full article

Egg parasitoids, such as Telenomus remus (Hymenoptera: Scelionidae), face significant challenges after release, as their pupae are exposed to various mortality factors that reduce the efficiency of biological control programs. Therefore, this study aimed to evaluate a honey-solid diet that can feed adults still inside the capsules without sticking the wasps on its surface, enabling parasitoid storage and later field release. Three independent bioassays were performed, each with 20 completely randomized replications. The first bioassay evaluated the acceptance of a solid feed—honey soaked in cotton thread—compared to the traditional form—honey droplets. In the second bioassay, the storage periods after emergence of adults in capsules with honey-solid food were analyzed at 2, 4, 6, and 8 days post-emergence, and the third bioassay studied the efficacy of different release densities of fed adults under field conditions. Parasitoids fed on the honey-solid diet exhibited a 13.3% reduction in parasitism compared to honey droplets. However, the sticky, viscous nature of honey can lead to parasitoids becoming glued, potentially leading to their death. T. remus feeding on the honey-solid diet resulted in low mortality inside the capsules, living up to six days with only 22.2% reduction in parasitism capacity, making it a viable alternative to release and transport fed adult parasitoids, with an increase of around 30% in the released density of parasitoids compared with the parasitoids fed on honey droplets. This flexibility of releasing T. remus up to six days after emergence provided valuable knowledge to establish T. remus as a biocontrol agent. Furthermore, the highest tested parasitoid density of 20,000 parasitoids per hectare obtained the highest parasitism of Spodoptera frugiperda (Lepidoptera: Noctuidae) eggs. However, future studies are still required with higher releasing densities and less expensive methods of mass rearing the parasitoid for those higher densities to be economically viable. Full article

The management of Meloidogyne incognita often depends on chemical nematicides, which pose environmental and health risks. This study investigated the potential of bacterial strains isolated from uncultivated native soil as biocontrol agents and plant growth-promoting rhizobacteria (PGPR) in tomato plants artificially infected with this nematode. Fifteen strains were screened in vitro for nematicidal and ovicidal activity, and four promising strains (307, GB16, GB24, and GB29) were selected for greenhouse trials. All strains reduced the nematode reproduction factor and the number of nematodes/g of root. Strains 307 and GB24 showed the highest reductions, 61.39 and 57.24%, respectively. Despite some positive physiological trends, Bacillus spp. did not promote a significant increase in plant growth. Metabolomic analysis revealed that the strains produced a wide range of primary metabolites with potential nematicidal activity. All strains also secreted proteases and chitinases, enzymes linked to nematode cuticle degradation. Preliminary identification based on the 16S rRNA gene and phylogenetic analysis grouped the four strains into the Bacillus subtilis group (strains GB16, GB29 and 307) or Bacillus cereus group (strain GB24); however, genome sequencing will be required in future studies. Overall, strains 307 and GB24 demonstrated strong biocontrol potential, supporting their use as sustainable and complementary alternatives to chemical nematicides. Full article

Tomato (Solanum lycopersicum) is an essential crop worldwide, yet it remains highly vulnerable to severe fungal and bacterial diseases. Traditional chemical-based disease management strategies, aimed at controlling these diseases face increasing scrutiny, due to concerns regarding pathogen resistance, environmental degradation, and potential health risks to humans. This has catalyzed the exploration of sustainable alternatives, with biological control emerging as a viable and promising strategy. Endophytic and epiphytic microorganisms are pivotal as biocontrol agents (BCAs), employing diverse strategies, such as generating antimicrobial substances, enzymes, and volatile organic compounds (VOCs), to suppress pathogen growth and enhance plant health. The efficacy of these antagonistic microorganisms is influenced by the cultivation systems employed, with significant variations observed between soil and hydroponic environments. Factors such as nutrient dynamics and microbial interactions play crucial roles in determining the success of BCAs in these different settings. The advent of metagenomic tools has transformed the landscape of microbial community research, facilitating the identification of functional genes associated with antagonistic activities and the adaptation of these microorganisms to diverse environmental conditions. This review aims to elucidate the potential of endophytic and epiphytic microorganisms in biological control, examining their mechanisms of action, the impact of cultivation systems on their effectiveness, and the application of metagenomics to optimize their use in sustainable disease management strategies for tomato crops. Full article

Species of Trichoderma are currently in high demand as eco-friendly and commercial biocontrol agents due to the proliferation of organic farming methods. This study focused on the potential biocontrol agents of Trichoderma against plant-pathogenic fungi. Trichoderma strains were isolated from different sources (soil, grapevine tissues, lemon fruit, and maize seeds), and were characterized morphologically on two culture media, i.e., Potato Dextrose Agar and Malt Extract Agar, and molecularly using two gene regions: translation elongation factor 1 (TEF) and nuclear ribosomal internal transcribed spacer (ITS). Phylogenetic trees were constructed. As a result, two Trichoderma species were identified, i.e., T. afroharzianum and T. longibrachiatum. The biocontrol effects of all isolated strains of Trichoderma on Fusarium plant damping-off and the promotion of plant growth were evaluated. Additionally, the antagonistic efficiency of Trichoderma spp. against F. proliferatum using the dual-culture method was evaluated. Under greenhouse conditions, T. afroharzianum strains AEMCTa3 and AEMCTa6 were used to treat maize plants infected with Fusarium. The application of Trichoderma significantly reduced the disease index to 15.6% and 0%, respectively. Additionally, maize seedlings showed significant improvements in shoot and root lengths and fresh and dry weights and increased photosynthetic pigment contents compared to Fusarium-infected plants and the untreated control. The gas chromatography–mass spectrometry (GC-MS) analysis of T. afroharzianum extracts identified a variety of bioactive compounds. These compounds included antifungal substances like N-ethyl-1,3-dithioisoindoline, as well as plant growth-promoting hormones like 6-pentyl-α-pyrone and gibberellic acid. Interestingly, the analysis also revealed new phenylacetic acid derivatives that may play important roles in both plant health and disease resistance. From a practical perspective, developing diverse application methods for Trichoderma is essential to optimize its role as a biocontrol agent and a plant growth promoter, thereby supporting sustainable agriculture through improved adaptability and effectiveness across different farming systems. Full article

Fusarium wilt is a devastating soilborne disease that significantly reduces watermelon production worldwide. This disease is caused by Fusarium oxysporum subsp. niveum (E.F.Sm.) W.C. Snyder & H.N.Hansen. Earthworms can influence fungal populations either by consuming or dispersing fungal propagules, making them a promising candidate for the biological control of Fusarium wilt. However, the underlying mechanisms remain poorly understood. In this study, we investigated the effects of adding the local earthworm species Metaphire guillelmi (Michaelsen, 1895) on Fusarium wilt in watermelon under field conditions, laboratory pot experiments, and laboratory pot experiments with sterilized soil. The results demonstrated that, compared to the control, the earthworm addition reduced the population of F. oxysporum by approximately 10⁵ copies/mg and suppressed the incidence of Fusarium wilt by 84.4%. A correlation analysis revealed that the abundance of F. oxysporum was negatively correlated with soil organic matter (SOM), available nitrogen (AN), and available phosphorus (AP). The relative interaction index values indicated that earthworms could enhance SOM and AN levels in the soil. A two-factor network relationship analysis showed that the earthworm addition could inhibit bacteria and fungi to stimulate growth of F. oxysporum while restraining them. A metabolomics analysis revealed that most differential metabolites associated with F. oxysporum were upregulated in the presence of earthworms. Overall, M. guillelmi can reduce the occurrence of Fusarium wilt by improving soil fertility, the relationship of F. oxysporum and microorganisms, and may influence the metabolic process, which need further exploration. It is a potential pathway for the biocontrol of Fusarium wilt. Full article

Fruits and vegetables are essential for a healthy diet, providing vital nutrients and contributing to global food security. Fungal pathogens that interact with fruits and vegetables reduce their quality and shelf life and lead to economic losses and risks to human health through the production of mycotoxins. Chemical fungicides, used to control postharvest pathogens, are posing serious environmental and health risks, driving interest in safer alternative strategies. Biocontrol methods using antagonistic microbes, such as yeasts, are eco-friendly, sustainable, and the most promising, but they often have limited efficacy and specificity in diverse produce. There is growing interest in the innovative enhancement of biocontrol strategies. The present review shows that inducing, enhancing, co-application, encapsulation, and post-application treatments are common enhancement techniques, while environmental, host, and pathogen characteristics, antagonistic microbial traits, and chemical inputs are the major gearing factors for the best application methods. These methods do not involve genetic modification, which is adequate to reduce the proliferation of GMOs (Genetically Modified Organisms) while optimizing antagonistic microbial performance by promoting growth, inducing host resistance, enhancing antifungal properties, improving adhesion, and boosting stress tolerance. Most enhancers fall under groups of nutritional additives, protective carriers, growth stimulants, and encapsulants. Integrating these enhancers and best methods promises reduced postharvest losses, supports sustainable agriculture, and addresses economic losses and food security challenges. This study highlights the role of organic and natural elicitors, their application methods, their mechanisms in improving BCAs (Biological Control Agents), and their overall efficiency. This review concisely compiles recent strategies, calling for further research to revolutionize fungal pathogen management, reduce food waste, and promote responsible farming practices. Full article

Conidiation and stress tolerance are pivotal traits in entomopathogenic fungi, critically influencing their production costs and environmental tolerance. While the transcription factor high-mobility group protein (HMG), characterized by a conserved HMG-box domain, has been extensively studied for its role in sexual development, its functions in entomopathogenic fungi remain largely unexplored. This study employed gene knockout to investigate the role of MaHMG in Metarhizium acridum. The deletion of MaHMG delayed conidiation initiation and caused a highly significant 58% reduction in conidial yield versus that of the wild type (WT) after 15 days. Furthermore, the conidiation pattern on microcycle induction medium (SYA) shifted from microcycle to normal conidiation. The ΔMaHMG mutant exhibited decreased conidial germination rates and markedly reduced tolerance following UV-B irradiation and heat-shock treatments, alongside increased sensitivity to the cell wall perturbant calcofluor white (CFW). RNA-seq analysis during this conidiation shift identified 88 differentially expressed genes (DEGs), with functional annotation implicating their predominant association with hyphal development, cell wall biogenesis, cell cycle progression, and conidiation. In conclusion, MaHMG functions as a critical positive regulator governing both conidiation and stress tolerance in M. acridum, underscoring its fundamental role in fungal biology and potential as a target for enhancing biocontrol agent performance. Full article

Iron is a limiting factor for plant and microbial growth because, in soil environments, it is predominantly present as oxyhydroxide minerals, rendering it unavailable to plants and microorganisms. Siderophores are chelating agents secreted to solubilize iron and facilitate its uptake. To understand the evolutionary and ecological dynamics of microbial communities, as well as the evolution of pathogens within hosts, it is essential to study the genes shared between microorganisms for environmental adaptation and survival. In this study, we conducted microbiological assays to evaluate the effect of the siderophore produced by Rouxiella badensis strain SER3 on the mycelial growth of fungal pathogens such as Fusarium brachygibbosum 4BF. Using spectrophotometric techniques and bioinformatics tools, we identified desferrioxamine E (nocardamine) in the culture supernatant, and the corresponding biosynthetic gene cluster in the SER3 genome was confirmed through antiSMASH analysis and synteny comparisons. Gene expression analysis by RT-PCR showed differential expression of biosynthetic precursors when strain SER3 was grown alone or in interaction with fungal pathogen. Finally, scanning electron microscopy revealed structural damage to F. brachygibbosum hyphae during co-culture with strain SER3. These results suggest that the production of desferrioxamine E may act as a biocontrol mechanism employed by R. badensis SER3 against F. brachygibbosum. Full article

The biocontrol strain Streptomyces pratensis S10 was isolated from tomato leaf mold. The fermentation broth of strain S10 can effectively control Fusarium head blight (FHB), caused by Fusarium graminearum. Enhancing antifungal activity is essential in advancing its commercialization. In this study, we aimed to improve the antifungal activity of S10 by integrating fermentation optimization and genetic engineering. Single-factor experiments revealed that seven parameters, namely corn flour, yeast extract, NaNO₃, CaCO₃, K₂HPO₄, KCl, ZnSO₄·7H₂O, and MnCl₂·4H₂O, were identified as significant components. A Plackett–Burman design (PDB) indicated that corn flour, yeast extract, and ZnSO₄·7H₂O were the most critical variables affecting its inhibitory activity and mycelial biomass. The fermentation medium was further determined based on the steepest climbing experiment and a Box–Behnken design (BBD), and the mycelial dry weight of S. pratensis S10 was improved from 2.13 g/L in Gauze’s synthetic No. 1 medium to 8.12 g/L in the optimized medium, closely aligning with the predicted value of 7.98 g/L. Under the optimized medium, the antifungal rate of F. graminearum increased from 67.36 to 82.2%. The spore suspension of strain S10 cultured in the optimized medium substantially improved its biocontrol efficacy against FHB. Moreover, disruption of the key gene tetR led to increased antifungal activity of strain S10 against F. graminearum. Importantly, the antifungal activity of ΔtetR was greatly increased under the optimized fermentation medium. This study suggests that the gene tetR negatively regulates bioactive compound biosynthesis, and the optimized medium provides favorable conditions for the growth of S10. These observations establish an extended basis for the large-scale bioactive metabolite secretion of S. pratensis S10, providing a strong foundation for sustainable FHB management in agriculture. Full article

Conidiobolus coronatus (Entomophthorales), a fungal pathogen with a broad insect host range, is a promising candidate for biocontrol applications. We sequenced a C. coronatus strain isolated from a Rhopalomyia sp. cadaver using PacBio long-read sequencing to elucidate the molecular basis of its wide host adaptability. The newly assembled 44.21 Mb genome exhibits high completeness (BUSCO score: 93.45%) and encodes 11,128 protein-coding genes, with 23.1% predicted to mediate pathogen–host interactions. Comparative genomics with the aphid-obligate pathogen C. obscurus revealed significant expansions in gene families associated with host adaptation mechanisms, including host recognition, transcriptional regulation, degradation of host components, detoxification, and immune evasion. Functional annotation highlighted enrichment in cellular component organization and energy metabolism. Pfam annotation identified one hundred twenty-five seven-transmembrane receptors (putative GPCRs), sixty-seven fungus-specific transcription factors, three hundred sixty-one peptidases (one hundred ninety-eight serine proteases and one hundred three metalloproteases), one hundred twenty-seven cytochrome P450 monooxygenases (P450s), thirty-five cysteine-rich secretory proteins, and fifty-five tyrosinases. Additionally, four hundred thirty carbohydrate-active enzymes (CAZymes) across six major modules were characterized. Untargeted metabolomics detected 22 highly expressed terpenoids, consistent with terpenoid biosynthesis gene clusters in the genome. Collectively, these expansions underpin the broad host range of C. coronatus by enabling cross-host signal decoding and gene expression reprogramming, breaching diverse host physicochemical barriers, and expanding its chemical ecological niche. This study provides genomic insights into broad host adaptability in entomopathogenic fungi, facilitating further understanding of pathogen–host interactions. Full article

Biocontrol is one of the most promising alternatives to chemical preservatives for food preservation. This study investigated the biocontrol potential of yeasts isolated from raw milk cheese against spoilage moulds. Eighty-four native yeast strains were screened for antagonistic activity against Penicillium commune, Fusarium verticillioides, and Mucor plumbeus/racemosus via confrontation using a milk-based culture medium. Fifteen strains from the species Pichia jadinii, Kluyveromyces lactis, Kluyveromyces marxianus, and Geotrichum candidum exhibited significant antagonistic activity (inhibition zone > 2 mm) against M. plumbeus/racemosus and F. verticillioides. The modelling of the impact of ripening conditions revealed that temperature was the primary factor influencing yeast antagonism. In addition, notable variability at both species and strain levels was found. The antagonist activity was associated with different mechanisms depending on the species and strains. K. lactis stood out for its proteolytic activity and competition for iron and manganese. Additionally, two strains of this species (KL890 and KL904) were found to produce volatile organic compounds with antifungal properties (phenylethyl alcohol and 1-butanol-3-methyl propionate). G. candidum GC663 exhibited strong competition for space, as well as the ability to parasitise hyphae linked to its pectinase and β-glucanase activity. The latter enzymatic activity was detected in all P. jadinii strains, with P. jadinii PJ433 standing out due to its proteolytic activity. In a cheese matrix, the efficacy of eight yeast strains against three target moulds was assessed, highlighting the potential of G. candidum GC663 and P. jadinii PJ433 as biocontrol agents, exhibiting high and moderate efficacy, respectively, in controlling the growth of F. verticillioides and M. plumbeus/racemosus. Nonetheless, further research is necessary to elucidate their full spectrum of antifungal mechanisms and to validate their performance under industrial-scale conditions, including their impact on cheese quality. Full article

Plant diseases caused by Rhizoctonia solani present a significant challenge in agriculture. While chemical pesticides remain a common control strategy, their use leads to health and environmental problems. In contrast, endophytic bacteria with plant growth-promoting (PGP) activity offer a promising, sustainable alternative. In this context, a novel endophytic Priestia megaterium strain, KW16, originated from the bluegrass (Poa pratensis L.), demonstrated distinct biocontrol potential against R. solani. in vitro assays showed that KW16 inhibited R. solani growth by up to 58%, primarily by releasing volatile compounds. In planta experiments further highlighted KW16′s ability to colonize oilseed rape internal tissues, significantly enhancing its growth and development. In the presence of the pathogen, KW16 abolished the negative impact of R. solani and promoted plant growth, increasing shoot and root biomass by 216% and 1737%, respectively, when compared to the plants grown in fungal-infested soil. Biochemical and genome analyses confirmed the strain’s metabolic versatility, resistance to biotic and abiotic factors, and a whole spectrum of PGP and biocontrol traits such as biofilm formation, production of phytohormones, and synthesis of lytic enzymes, siderophores, and volatiles, alongside its ability to survive in the presence of autochthonous soil microflora. These findings position KW16 as a potent biological alternative to synthetic fungicides, with significant potential for sustainable crop protection. Full article

Ambrosia beetles, known for their symbiotic relationship with fungi cultivated within the tissues of host trees, have become significant pests, particularly when they serve as vectors for pathogenic fungi such as Raffaelea lauricola. Given the regulatory and environmental constraints for chemical application as a tool for their control, entomopathogenic fungi (EPF) represent a promising pest management alternative. This review presents an overview of bioassays assessing the pathogenicity and virulence of EPF against ambrosia beetles. Most studies have been performed in vivo (artificial diet) under laboratory conditions, focusing on exotic species and testing EPF genera such as Beauveria, Metarhizium, Isaria, and Purpureocillium. However, variations in inoculation methods, environmental conditions, and fungal formulations, have led to diverse results. In addition, the complex biology of these insects, particularly their dependence on symbiotic fungi, represents significant methodological challenges. Field trials (in situ bioassays) are still scarce, and there is a need to move toward standardized protocols and more objective experimental models that consider not only insects’ behavior but also ecological factors. Bridging this gap is essential for successfully implementing EPF-based strategies to assess ambrosia beetles’ biocontrol. Full article

Pineapple (Ananas comosus) is an important crop worldwide, due to its nutritional properties. It is well known as a rich source of vitamins (A, C, and D) and various minerals that are vital in human diets. The aim of this review was to explore the economic viability of organic fertilizers that improve growth, yield, and quality during pineapple production in Africa. This study was conducted through a comprehensive analysis of the literature from peer-reviewed journals. It was reviewed that organic fertilization is a general agricultural approach that prioritizes environmental sustainability, biodiversity, and soil health through the avoidance of chemicals, including inorganic fertilizers. It was also found that organic fertilizers can effectively improve growth performance, yield, and the quality of the pineapple fruit to levels comparable to those of the fruit grown using inorganic fertilizers. Subsistence and smallholder farmers have adopted organic fertilization more than commercial farmers. Various challenges, including high certification costs, limited market access, high operating costs, inadequate farmer training, and limited knowledge on producing fruit using organic fertilizers, have been reviewed. The potential for higher market prices for organically produced fruit was noted, together with the challenges. Despite higher market prices and environmental benefits from organic fertilization, the economic viability of organic fertilizers for pineapple production is constrained by other factors, such as pest management difficulties, as the policies of conservation agriculture limit the use of chemical pesticides or the introduction of alien species as biocontrol agents. Full article