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Characterization and genomic analysis of Bacillus halotolerans G3-2: a potential biocontrol agent against apple Alternaria leaf blotch disease.

BACKGROUND: Apple Alternaria leaf blotch (ALB) is a devastating disease threatening the apple industry worldwide. Biocontrol offers an effective and environmentally friendly alternative for disease management. RESULTS: Bacillus strain G3-2 exhibits strong antagonistic activity against Alternaria alternata (a major causal pathogen of ALB). In dual-culture assays, G3-2 inhibited A. alternata by 88.39%; in detached-leaf inoculation assays, it reduced the lesion area by >88%. 16S rRNA sequencing and phylogenetic analysis identified this strain as Bacillus halotolerans. Oxford Nanopore Technology (ONT) sequencing generated a 4.18-Mb complete genome (43.8% G + C) containing 4149 protein-coding genes, 30 rRNAs and 86 tRNAs. CAZy annotation identified 182 genes encoding carbohydrate-active enzymes (CAZymes), including glycoside hydrolases, glycosyltransferase, and carbohydrate esterases, suggesting potential for glycosylated secondary metabolite production. AntiSMASH analysis detected nine biosynthetic gene clusters, including those for surfactin, fengycin, bacillaene and laterocidine. Plate assays confirmed that G3-2 has the ability to produce protease, cellulase and siderophore. Moreover, it exhibits ~70% inhibition against several other phytopathogenic fungi. CONCLUSIONS: These findings demonstrate that G3-2 suppresses A. alternata through antibiosis (lipopeptides and polyketides), nutrient competition (siderophores) and cell-wall degradation (proteases and cellulases). Moreover, our study revealed that it has great potential to be used as a broad-spectrum, environmentally friendly biocontrol agent. © 2026 Society of Chemical Industry.

Alternaria

The genomic resource of Lysinibacillus fusiformis KBD-5, a biocontrol agent with antifungal activity against Botrytis cinerea.

Lysinibacillus fusiformis strain KBD-5, previously known for its antiviral activity against Tobacco mosaic virus, was investigated for its biocontrol potential against the fungal pathogen Botrytis cinerea. In plate assays, conducted with three independent biological replicates and incubated at 28 °C for 5 days, KBD-5 significantly inhibited the mycelial growth of B. cinerea by 76.42%. Whole-genome sequencing revealed a 4.69 Mb genome with a GC content of 37.28%, encoding 4719 proteins. Bioinformatics analysis identified genes involved in antimicrobial functions, including 195 carbohydrate-active enzymes (potentially aiding in fungal cell wall degradation) and 8 gene clusters for secondary metabolite synthesis (e.g., T3PKS with 30% similarity to bacillibactin biosynthetic clusters and NRPS), indicating the production of antifungal metabolites like bacillibactin-like polyketides. The strain also showed a high safety profile with no significant virulence or drug resistance risks. These findings indicate that genomic analysis of KBD-5 reveals the potential for multiple biocontrol mechanisms, supporting its potential development as a biocontrol agent. The draft genome sequence is available under NCBI accession PRJNA1335659.

Botrytis

Herbicolin A, an antifungal lipopeptide produced by Pantoea agglomerans APC 4211 is a promising biocontrol agent against food spoilage fungi.

Fungal contamination of food with yeast and molds is associated with major economic losses due to spoilage and also poses health risks in the form of mycotoxin production. The strain Pantoea agglomerans APC 4211 isolated from leaves of Ilex aquifolium (holly tree) has broad spectrum antifungal activity against a variety of food spoilage fungi. Genomic analysis of the strain confirmed the presence of biosynthetic gene clusters potentially encoding for the enzymatic machinery required for the production of the antifungal lipopeptide herbicolin A. Matrix-assisted laser desorption ionization-time of flight mass spectrometry (MALDI-TOF MS) analysis of the cell-free supernatant (CFS) confirmed the presence of molecular masses corresponding to herbicolin A (1300.8 Da), and herbicolin B (1138 Da). Purified herbicolin A has desirable properties for biotechnological applications, including potent antifungal activity against a range of spoilage fungi, thermal stability and resistance to proteases. The lipopeptide has low cytotoxicity against epithelial cell lines and has minimum inhibitory concentrations (MICs) lower than those of some commercial antifungal drugs (0.2-2.5 mg/L). In a model dairy system (10% skim milk), herbicolin A demonstrated excellent solubility and stability, effectively eliminating Aspergillus niger and Penicillium notatum at a concentration of 5 mg/L. Overall, the study determines herbicolin's A spectrum against food spoilage organisms and examines potential applications in food. In conclusion, herbicolin A is a potent, naturally occurring antifungal agent with the potential to be applied as a biopreservative in food systems, providing a safe, clean-label, and efficient compound for synthetic preservatives replacement.

Pantoea

Recent Advances in the Comprehension of Molecular and Genetic Mechanisms Underlying Yeast Biocontrol Efficacy Against Fungal Pathogens in Agriculture.

Recent advances in biotechnologies have enabled scientists to uncover biological processes across multiple research fields. Still, the molecular and genetic mechanisms underlying the biological control efficacy of yeast biocontrol agents (YBCAs) against fungal plant pathogens remain incompletely elucidated. This review focuses on recent insights into the regulatory bases and molecular interplay underlying successful disease control by YBCAs. It provides a detailed description of core antagonistic molecular mechanisms-nutrient and iron competition, mycoparasitism via cell wall degradation, antifungal compounds production, oxidative stress resistance, biofilm formation and colonization, and induction of the host defense responses-and integrates genomic, transcriptomic, proteomic, and metabolomic evidence to elucidate each mechanism. Further, how genetic engineering-based approaches that leverage omics data and functional genetics can help overcoming obstacles to translate YBCAs efficacy from laboratory conditions to the field are also discussed. Finally, the use of the CRISPR-Cas technology is recommended to better exploit how master transcription factors coordinate multiple mechanisms simultaneously; these factors are crucial for the synergistic antifungal effect, which is critical for developing highly effective YBCAs. Ultimately, the mechanism-based perspective provides a unified conceptual framework for understanding YBCAs efficacy and can guide the rational design of next-generation biocontrol agents for sustainable agriculture.

CRISPR-Cas technology

Synergistic transcriptional modules in Trichoderma asperellum enhance glutathione detoxification to counteract fungal pathogen toxins.

Trichoderma fungi are potent biocontrol agents. However, their defence mechanisms against pathogen-derived toxins remain poorly understood. We identified two synergistic transcription factor modules in T. asperellum that orchestrate the detoxification of cytotoxic secondary metabolites from the poplar blight pathogen Alternaria alternata. Overexpression of the central regulator TasMYB46 reduced disease lesion area by approximately 22% and was associated with decreased pathogen-induced reactive oxygen species (ROS) accumulation. Mechanistically, TasMYB46 directly activates the glutathione S-transferases TasGST61.1 and TasGST56.1 through distinct promoter binding sites (G-box/as-1/MBS), forming dedicated detoxification modules. Crucially, we identified urolithin C as the most abundant phytotoxin in A. alternata metabolites, which is efficiently detoxified through the TasMYB46-TasGST61.1 module. The transcription enhancer TasbHLH53.8 amplifies this system by binding to TasMYB46, boosting TasGST expression and enhancing glutathione-dependent detoxification capacity. This coordinated response elevates glutathione pools and antioxidant enzyme activities (GST/GPx), conferring increased oxidative stress resistance. This study reveals a novel defence mechanism in Trichoderma in which MYB-bHLH-GST modules enable biocontrol agents to neutralise pathogen-derived toxins. Given that Alternaria toxins threaten crops globally (tomatoes, potatoes, citrus), the discovered regulatory synergy represents a strategic advance in developing next-generation biocontrol solutions against toxin-producing plant pathogens.

Alternaria

The utilization of Salmonella phage in milk and chicken: depolymerase identification and potential for anti-biofilm activity.

Bacteriophage (phage)-based biocontrol presents a promising strategy against foodborne pathogens. In this study, a novel phage, PH215, exhibited lytic activity against seven prevalent Salmonella serotypes, was isolated and characterized. PH215 demonstrated remarkable environmental stability, sustaining infectivity across a wide pH range (2-11) and at temperatures from 4 to 50 °C. The multiplicative potential of PH215 was evidenced by a low multiplicity of infection (MOI) of 10-6, a short latent period of 10 min, and a substantial burst size of approximately 50 PFU per infected cell. Genomic analysis revealed a 43,505 kb double-stranded DNA genome encoding 67 putative proteins. Notably, the product of the Peg38 gene, identified as a tail spike protein (termed PH215Depo), possessed depolymerase activity. We have shown that the cloned expression of PH215Depo exhibited enzymatic activity against various Salmonella serotypes and significantly impeded biofilm formation. Furthermore, in practical application models, PH215 application reduced Salmonella counts in milk and chicken by 2.04 to 5.37 log10 CFU/mL. Our findings highlight the potential of depolymerase-encoding phages like PH215 as effective and broad-spectrum biocontrol agents against Salmonella in the food industry.

Biofilms

Endophytic fungi isolated from coffee plants promote Arabidopsis thaliana growth and suppress soil-borne fungal pathogens.

Endophytic beneficial microorganisms are widely used in agriculture for promoting plant growth and enhancing plant defense mechanisms. This study aimed to characterize endophytic fungi isolated from the roots of coffee plants cultivated in organic agroforestry systems and evaluate their potential as biocontrol agents against fungal pathogens, as well as their ability to promote plant growth. Biocontrol activity was assessed using in vitro dual-culture assays on potato dextrose agar, measuring the inhibition of pathogen growth. Plant growth promotion was evaluated by co-cultivating Arabidopsis thaliana seedlings with fungal isolates on Murashige and Skoog medium. Isolates were further subjected to both qualitative and quantitative biochemical characterization. A total of 18 endophytic fungal strains were identified and classified in five genera: Colletotrichum, Fusarium, Simplicillium, Lasiodiplodia and Trichoderma. Among these, ten Trichoderma isolates demonstrated strong antagonistic activity against selected fungal pathogens and significantly enhanced the growth of Arabidopsis seedlings in vitro. These beneficial effects were associated with the production of siderophores and indole-3-acetic acid, as well as the apparent nitrogen availability -- likely mediated through interactions with nitrogen-fixing bacteria.

Arabidopsis

Metagenomic analysis of microbial community dynamics in konjac rhizosphere during soft rot disease progression.

Amorphophallus konjac, the sole glucomannan-rich species in the Araceae family, faces significant yield and quality losses due to soft rot disease. Understanding the relationship between soil microbial communities and soft rot incidence is critical for sustainable konjac production. Metagenomic profiling was employed to systematically characterize the spatiotemporal dynamics of rhizosphere microbiomes during disease progression. Microbial alpha diversity (Chao1 index) exhibited a significant peak in the rhizosphere of diseased plants at the mature stage, contrasting with stable diversity patterns in healthy and latently infected groups, indicating dysbiosis-associated richness inflation during disease progression. Principal coordinate analysis (PCoA) revealed significant divergence in rhizosphere microbial structures between diseased and healthy/latently infected groups, with higher compositional variability observed in diseased samples. At the phylum level, Chloroflexi and Acidobacteria abundances in healthy mature plants exceeded those in diseased plants by 11.54% and 4.6%, respectively, while pathogenic Rhizopus arrhizus and Rhizopus microsporus were significantly enriched in diseased mature plants. Correlation analyses demonstrated predominantly negative associations between bacterial species and soil factors, contrasting with positive fungal correlations. KEGG pathway annotation identified carbohydrate metabolism and amino acid synthesis as core microbial functions in the konjac rhizosphere. Collectively, Chloroflexi and Acidobacteria were validated as putative biocontrol agents, while Rhizopus spp. emerged as key drivers of soft rot development. These findings provide mechanistic insights for designing microbiome-based biocontrol strategies to mitigate konjac soft rot, offering a sustainable alternative to conventional agrochemical reliance. KEY POINTS: • Diseased konjac microbial richness peaks; healthy plants enrich Chloroflexi/Acidobacteria. • Rhizopus pathogens drive soft rot; bacteria and fungi show opposing soil factor links. • Lays groundwork for microbiome approaches to cut agrochemicals in konjac rot control.

Rhizosphere

Integrated assessment of biocontrol potential and genome analysis of endophytic Bacillus velezensis MGL-B1 against mango stem-end rot.

Mango stem-end rot is a globally significant postharvest disease that severely threatens the mango industry, primarily caused by Botryosphaeria dothidea. However, information on biocontrol agents targeting this pathogen in mango remains limited. In this study, we isolated and identified a strain of Bacillus velezensis MGL-B1 from mango leaf tissues for the first time, which exhibited broad-spectrum antifungal activity. Both in vitro and in vivo assays demonstrated that MGL-B1 effectively inhibited the growth of B. dothidea, with an in vivo biocontrol efficacy reaching 83.72 ± 5.10%, comparable to that of the commonly used chemical fungicide thiabendazole. Further mechanistic analysis revealed that MGL-B1 acts by directly disrupting the integrity of the pathogen's mycelial cell membrane. In addition, its released volatile organic compounds (VOCs) also displayed significant antifungal activity, with components such as 2-nonanone, 2-nonanol, and phenylethyl alcohol being confirmed to exert antifungal effects in in vitro fumigation assays. qPCR analysis showed that MGL-B1 treatment significantly upregulated the transcriptional levels of genes involved in plant-pathogen interaction, phenylpropanoid biosynthesis, and antioxidant defense pathways in mango fruits, with upregulation folds of 16.32, 37.19, and 75.93, respectively; meanwhile, the expression of browning-related genes such as polyphenol oxidase (PPO) was markedly suppressed. Whole-genome sequencing further revealed 14 biosynthetic gene clusters for antimicrobial compounds, including five unknown gene clusters. Collectively, B. velezensis MGL-B1 represents a promising biocandidate strain with multiple antifungal mechanisms and excellent control efficacy, providing a valuable resource for green and sustainable management of mango diseases.

Mangifera

Biocontrol Potential of a Novel Bacillus velezensis Strain Against Major Soft Rot Bacteria Pectobacterium and Dickeya.

Management of soft rot Pectobacteriaceae (SRP) remains a major challenge because effective control options such as bactericides, chemical treatments, or resistant commercial varieties are currently lacking. In a quest for an effective control measure against SRP, we isolated bacteria from soil and potato samples from potato fields across Montana. The bacterial isolates were screened for their effective suppression of major soft rot and blackleg pathogens Pectobacterium brasiliense strain Pb1692 and Dickeya dianthicola strain ME23. We screened more than 3,000 bacterial isolates using inhibition-zone assays on nutrient agar plates. From this collection, we identified a strong antagonist effective against Pb1692 and ME23. This isolate successfully suppressed potato soft rot and blackleg disease in both laboratory and greenhouse evaluations. Genome sequencing identified the bacterial antagonist as Bacillus velezensis strain DN539, which can survive well at 8°C, a potato postharvest storage temperature. We enriched the B. velezensis DN539 supernatant in bioactive fractions, and mass spectrometry analysis identified the bioactive compound as isomers of surfactin. Scanning electron microscopy identified that surfactin-enriched fraction resulted in the leakage of the cellular content of phytobacteria tested in our study in as little as 10 min, followed by complete degradation of bacterial cells within 1 h. The surfactin-enriched fraction also had antimicrobial effects against other economically important phytobacteria such as Erwinia amylovora, Xanthomonas campestris, and Pseudomonas syringae. These indicate that surfactin synthesized by Bacillus velezensis DN539 has potential to be developed as a biocontrol agent against broad range of phytobacteria.

Pectobacterium

Lytic properties and genomic analysis of bacteriophage Brt_Psa3, targeting Pseudomonas syringae pv. actinidiae.

Pseudomonas syringae pv. actinidiae (Psa) is the causative agent of bacterial canker in kiwifruit (Actinidia spp.). Psa biovar 3 is the most prevalent and virulent, causing frequent and severe outbreaks worldwide. While current treatments have low efficacy, bacteriophages emerge as possible environmentally safe alternative biocontrol agents. In this study, bacteriophage Brt_Psa3 was isolated from the soil of a kiwifruit orchard in Portugal. Morphologically, Brt_Psa3 forms clear plaques and has a Podoviral morphotype. The bacteriophage exhibited broad lytic activity against several plant-pathogenic Pseudomonas strains, including Psa isolates. The isolated bacteriophage has a latent period of 100 min, a burst size of 143 particles/cell, and demonstrates stability at different temperatures and pH values found in kiwifruit orchards. In addition, Brt_Psa3 exhibited tolerance to UVA irradiation during 120 min of incubation. Brt_Psa3 belongs to the Autographiviridae family and Ghunavirus genus, based on full-genome nucleotide alignment and supported by phylogenetic analysis of structural proteins. The phage contains 51 open reading frames with no antibiotic resistance genes identified, within a genome of 40.509 base pairs. In vitro experiments with kiwifruit leaves demonstrated significant reduction of Psa levels (40%) on leaf surfaces, highlighting the bacteriophage's therapeutic potential in managing bacterial canker in kiwifruits.

Pseudomonas syringae

Emerging prospects of Bacillus species in attaining the sustainable development goals.

The world is witnessing a serious challenge of poverty which is reflected as hidden hunger and simultaneously overpopulation puts a grave burden on our ecosystem. In order to overcome these serious issues, the sustainable development goals (SDGs) serve a very significant role. Concurrently, the contribution of microorganisms in achieving the SDGs cannot be overlooked. Bacillus species as a probiotic has led to the development of various commercial fermented products that are available in the market. Additionally, the formulated products have been clinically validated for their health benefits. Bacillus species have also been reported to serve as bio-preservatives and biocontrol agents because they aid in preserving and maintaining the final food product as well as post-harvest goods. The utilization of Bacillus spp. as probiotics has significantly contributed to the overall well-being of animals. Moreover, many different species of Bacillus have been reported to be utilized as bio-cementing agents. All the aforementioned roles of Bacillus species contribute to addressing zero hunger (SDG 2), good health and well-being (SDG 3), and industry, infrastructure, and innovation (SDG 9). KEY POINTS: • Role of Bacillus spp. as probiotic have been successfully proven by clinical studies. • Prescence of antimicrobial genes in the Bacillus spp. genome play important role in bio-preservation and biocontrol. • In animal feeds Bacillus spp. are a good alternate of antibiotics and use of Bacillus spp. in cement industry is innovative approach.

Bacillus

Biocontrol Potential and Mechanism of Endophytic Bacillus velezensis WSR1 Against Rubber Tree Anthracnose.

Fungal leaf anthracnose, caused by Colletotrichum species, is a major leaf disease of rubber trees, significantly reducing global natural rubber yields. To explore sustainable and safe biological control strategies, eight bacterial strains were isolated from rubber tree tissues, demonstrating antagonistic activity against Colletotrichum pathogens (C. siamense and C. australisinense). Among these, WSR1 exhibited the most pronounced antifungal effect, with inhibition rates of 87.64 and 89.03% against C. siamense and C. australisinense, respectively. Genomic analysis identified WSR1 as Bacillus velezensis. In pot experiments, WSR1 exhibited preventive efficacy of 77.24 and 73.42% for C. siamense- and C. australisinense-induced anthracnose, respectively, with therapeutic efficacy of 42.28 and 45.57%. WSR1 compromised the integrity of the cell walls and membranes of both C. siamense and C. australisinense, while inducing reactive oxygen species accumulation within the hyphae. Additionally, WSR1 enhanced rubber tree resistance to anthracnose by activating defense-related enzymes, including phenylalanine ammonia-lyase, polyphenol oxidase, and peroxidase. Plate assays and genomic analysis revealed that WSR1 secretes fungal cell wall-degrading enzymes (cellulases, pectinases, and proteases) and siderophores. Furthermore, liquid chromatography-mass spectrometry and gene cluster analysis confirmed the synthesis of antagonistic secondary metabolites, such as surfactin, macrolactin H, and fengycin. This study represents the first identification of B. velezensis as a potential biocontrol agent against rubber tree anthracnose, offering a promising candidate for the eco-friendly management of rubber tree diseases.

C. australisinense

Identification of an antifungal lipopeptide from Bacillus amyloliquefaciens HAU3 inhibiting the growth of Fusarium graminearum using preparative chromatography and 2D-NMR.

UNLABELLED: The presence of fungal contamination and its mycotoxins in animal feed is pervasive, posing a significant threat to the well-being and performance of animals, as well as the safety of animal-derived food products. In this work, we screened a strain of Bacillus amyloliquefaciens (B. amyloliquefaciens) HAU3 that exhibits efficient antifungal activity against the growth of Fusarium graminearum (F. graminearum). The antifungal activity was detected in the supernatant, with 20% sterile supernatant demonstrating an impressive antifungal rate of 98.46% against F. graminearum. The antifungal activity of the strain was evaluated through spectrum analysis and silage trials, revealing its effective antifungal activity against multiple fungal species. Furthermore, the strain is capable of degrading ZEN and its derivatives. The targeted disruption of fungal mycelial membrane was observed using scanning electron microscopy and transmission electron microscopy. Additionally, staining with the reactive oxygen species (ROS)-sensitive fluorogenic dye DCFH-DA and propidium iodide (PI) revealed that the strain induces accumulation of ROS in fungal mycelia. The active compounds underwent further separation, purification, and detection. The prominent active peak was identified through mass spectrometry and magnetic resonance spectroscopy. The molecular structure of the active compounds was predicted to be lipopeptides composed of 8 amino acids known as fengycin. The whole genome sequencing and informatics analysis unveiled a total of 13 gene clusters responsible for the synthesis of secondary metabolites. The antifungal effects of B. amyloliquefaciens HAU3 are exerted through the synthesis of fengycin, which selectively targets and compromises the integrity of fungal mycelia membranes, thereby making it a potential biocontrol agent for mitigating mycotoxin contamination in feed. IMPORTANCE: Mycotoxin contamination in animal feed, predominantly driven by Fusarium graminearum, represents a persistent threat to livestock health and food chain integrity. Here, we report the isolation of a soil-derived Bacillus amyloliquefaciens HAU3, exhibiting potent and broad-spectrum antifungal activity alongside efficient biodegradation of zearalenone and its derivatives. Mechanistic dissection reveals that fengycin, the principal bioactive metabolite, compromises fungal membrane integrity and elicits intracellular oxidative stress, culminating in hyphal collapse. Genomic profiling uncovers a diverse repertoire of biosynthetic gene clusters underpinning secondary metabolite production. These findings establish strain HAU3 as a promising microbial chassis for the development of next-generation biocontrol strategies aimed at mitigating mycotoxin burden in agroecosystems.

Bacillus amyloliquefaciens

Characterization and classification of a novel bacteriophage, vB_RsoP_HXg1W, infecting Ralstonia pseudosolanacearum: a new member of the genus Serkorvirus in the family Autotranscriptaviridae.

Bacterial wilt caused by Ralstonia solanacearum species complex (RSSC) is a significant threat to agriculture due to the pathogen's broad host range and persistence in soil. Bacteriophages (phages) are being explored as biocontrol agents, and such strategies are gaining interest. In this study, we isolated and characterized vB_RsoP_HXg1W, a novel phage propagated on R. pseudosolanacearum GMI1000. The phage has a linear double-stranded DNA genome of 40,184 bp with a GC content of 62.3%, and displays an icosahedral head with a short tail. A total of 51 open reading frames (ORFs) were identified, and no tRNA genes were detected. Comparative genomic and phylogenetic analyses revealed that vB_RsoP_HXg1W is closely related to Ralstonia phage p2137, p2106, and RpY2, and clusters within the genus Serkorvirus in the family Autotranscriptaviridae. VIRIDIC analysis revealed a maximum intergenomic similarity of 84.7% to the closest included relative, supporting vB_RsoP_HXg1W as a putative novel species-level member of Serkorvirus. These findings contribute to the understanding of RSSC-infecting phages and provide a foundation for further exploration of phage evolution, host range, and biocontrol relevant traits.

Ralstonia

Doublesex gene influences sex differentiation and embryonic development in predatory mite Phytoseiulus persimilis.

BACKGROUND: Phytoseiulus persimilis is an effective biocontrol agent characterized by paternal genome elimination (PGE), an unusual reproductive system in which males eliminate the paternal genome during embryogenesis. However, the molecular mechanism underlying sex determination and reproductive regulation in this species remain poorly understood. RESULTS: Transcriptome-based analyses identified two doublesex (dsx) homologs, Ppdsx1 and Ppdsx2, as candidate regulators of reproduction. Weighted gene co-expression network analysis (WGCNA) assigned Ppdsx2 to a pre-mating-associated co-expression module enriched for reproductive and signaling pathways. Functional analyses revealed clear divergence between the two genes. RNA interference (RNAi) of Ppdsx1 reduced the proportion of female offspring, whereas RNAi of Ppdsx2 induced sex reversal, developmental abnormalities, and impaired egg viability. Yeast two-hybrid and glutathione S-transferase (GST) pull-down assays further demonstrated interactions between Dsx proteins and vitellogenin (Vg)-derived fragments identified from a complementary DNA (cDNA) library screen, suggesting a previously unrecognized connection between sex determination and reproductive nutrient allocation. CONCLUSIONS: Ppdsx1 contributes to maintenance of the female developmental pathway, whereas Ppdsx2 represents a strong candidate component of the PGE-associated sex-determination cascade. The observed Dsx-Vg fragment interaction suggests a potential link between reproductive developmental programs and nutrient allocation pathways. These findings provide new insights into the molecular basis of sex determination and reproductive regulation in phytoseiid mites and establish a foundation for future studies on the coupling of reproductive development and resource allocation. © 2026 Society of Chemical Industry.

Animals