Search Results (548)

Botrytis cinerea, the causal agent of gray mold or Botrytis rot on many vegetable and fruit crops worldwide, is ranked among the main limiting factors for strawberry production, being able to strongly compromise the quality, shelf life, and commercial value of fruit. UV-C is considered an environmentally friendly strategy for postharvest protection for several commodities. In this regard, this research evaluated the performance of short-wavelength UV-C radiation in reducing postharvest Botrytis decay, extending or maintaining the shelf life and quality of strawberry fruit, and detecting possible negative effects. The topic is of growing interest, as it falls within the strategic priorities of so-called “Green Technologies” to pursue a sustainable agriculture and safe food supply by minimizing fungicide use as much as possible. UV-C exposure (at a rate of 1428 J m⁻²) by means of a UV-C lamp (15 W) at a source distance of 25 cm for just 1 min provided significant reductions (from 41 up to almost 80%) depending on the artificial or natural decay pressure of gray mold caused by B. cinerea on strawberry fruit without phytotoxic effects. Analyses performed under both refrigerated and room-temperature storage conditions at different day intervals showed that postharvest UV-C does not significantly affect key chemical parameters, including the ascorbic acid content, total sugars, pH, and titratable acidity of strawberry fruit. Thus, UV-C exposure for a brief time, especially if combined with a low temperature, can be effectively considered for sustainable protection of strawberry fruit at the postharvest stage, providing a theoretical basis for further elucidation of the action modes for this and other targets, and potential large-scale application. Full article

The Australian sea lion (Neophoca cinerea) is an endangered species with threats including bycatch, prey depletion, pollution, and habitat loss. Coastal and offshore industrial development causes disturbance—largely mediated by noise. Yet nothing was known about this species’ hearing sensitivity. We present the first in-air audiograms of two adult female Australian sea lions, measured between 100 Hz and 20 kHz via behavioral audiometry. Greatest sensitivity occurred at 3.2 kHz at 13 and 14 dB re 20 µPa in the two individuals. Their 20 dB bandwidth of best sensitivity ranged from 600 Hz to 9 kHz in one and to at least 20 kHz in the other sea lion. While these audiograms were generally comparable to those published for other sea lion species, frequencies of best sensitivity were lower in the Australian sea lions. These results may add to future research on comparative ecology in pinnipeds and inform the management of anthropogenic noise. Full article

Gray mold caused by Botrytis cinerea severely limits the postharvest quality of rose, but the contribution of ATP-binding cassette (ABC) transporters to rose defense remains unclear. Here, we identified 185 RcABC genes in the Rosa chinensis genome and classified them into eight subfamilies, with RcABCG as the largest subfamily. DESeq2-based RNA-seq analysis identified 13 significantly upregulated RcABC genes in response to B. cinerea infection at 48 hpi, nine of which belonged to the RcABCG subfamily. At 48 hpi, the log₂ fold changes of these induced genes ranged from 1.34 to 7.98, and RcABCG5, RcABCG50, RcABCG59, and RcABCG60 were selected for functional analysis. Further phylogenetic, gene-structure, and promoter analyses showed that several full-size RcABCG members were closely related to previously reported defense-associated ABCG transporters and harbored predicted GA-, MeJA-, and ABA-responsive cis-elements. Virus-induced gene silencing reduced the relative transcript levels of RcABCG5, RcABCG50, RcABCG59, and RcABCG60 to 22.8%, 17.9%, 35.2%, and 27.5% of the TRV-GFP control, respectively. Mean lesion area increased from 39.27 mm² in TRV-GFP discs to 44.96, 46.95, and 43.23 mm² in RcABCG5-, RcABCG50-, and RcABCG59-silenced discs, respectively, whereas no significant lesion increase was observed in RcABCG60-silenced discs. Together, these results establish a genome-wide framework for defense-related ABC transporters in rose and identify RcABCG5/50/59 as candidate genes associated with gray mold resistance under VIGS conditions. Full article

Salvia somalensis Vatke is a source of specialized metabolites with potential biological and agrochemical applications. Previous studies on the dichloromethane plant surface extract demonstrated strong antifungal activity associated with abietane diterpenoids. Building on these findings, the present study aimed to characterize the methanolic extract of S. somalensis and evaluate its antifungal potential against major phytopathogenic fungi, with the broader goal of exploring the extract as a sustainable source of antifungal metabolites for crop protection. LC-MS analysis of the methanolic extract revealed a diverse phytochemical profile comprising phenolic acids, including caffeic acid, ferulic acid, and rosmarinic acid, as well as abietane-type diterpenoids such as carnosol, rosmanol, and carnosic acid. Quantitative analysis showed that carnosic acid was present only at low levels (0.09% w/w of fresh biomass). The extract exhibited antifungal activity against Botrytis cinerea, Colletotrichum coccodes, Fusarium oxysporum, Rhizoctonia solani, and Sclerotinia sclerotiorum. More than 80% inhibition of mycelial growth was observed against B. cinerea and C. coccodes at 1000 μg/mL. In addition, as in vitro cultivation of this species has not previously been explored, micropropagated plants and callus culture were established. Phytochemical profiling revealed distinct chemical compositions in the in vitro biomass. Extracts obtained from micropropagated plants inhibited mycelial growth of the tested phytopathogens by 60–70% at 1000 μg/mL, except for F. oxysporum, which showed 35.29% inhibition at the same concentration. Collectively, these findings highlight S. somalensis as a source of bioactive metabolites with antifungal potential. Full article

With growing global recognition of the nutritional value of blueberries, their cultivation has expanded significantly across various regions. However, gray mold disease, caused by Botrytis cinerea, remains a major challenge in postharvest storage and transportation. In this study, two strains—Trichoderma asperellum BBR–A and B. cinerea BC7–1—were isolated and identified from the blueberry rhizosphere and diseased leaves. Co-culture assays demonstrated that BBR–A exhibits potent antagonistic activity, rapidly suppressing the growth of the pathogen BC7–1 through mycoparasitic behaviors, including hyphal coiling, penetration, and degradation. Transcriptomic analysis revealed that upon interaction with BC7–1, BBR–A undergoes extensive reprogramming of carbon metabolism, with coordinated upregulation of genes encoding degradative enzymes, transporters, and stress-related proteins. Congo red staining and enzymatic activity assays further confirmed the enhanced secretion of extracellular enzymes and the increased cell wall-degrading capacity of BBR–A. On detached blueberry leaves, seedlings, and fruits, BBR–A treatment significantly delayed lesion expansion and reduced disease severity. Metabolomic profiling further demonstrated that BBR–A induces the marked accumulation of phenolic compounds, polyamines, and other antioxidant- and immunity-related metabolites in blueberry leaves, thereby maintaining host redox homeostasis and enhancing stress resilience. Collectively, these findings indicate that T. asperellum BBR–A effectively suppresses B. cinerea through multiple mechanisms, including antagonism, mycoparasitism, metabolic regulation, and the induction of plant defense responses, highlighting its strong potential for development as a biocontrol agent against blueberry gray mold. Full article

Ethylene response factors (ERFs) are transcription factors specific to plants that serve critical functions in various aspects of plant growth, development, and responses to environmental stressors. Despite the significance of these factors, the specific mechanisms by which mulberry ERFs interact with and respond to the pathogenic fungus Botrytis cinerea have not yet been fully elucidated. This study focuses on the isolation of a particular ERF transcription factor, known as MnERF/ABR1, which is localized in the cell nucleus and is derived from mulberry. Overexpression of MnERF/ABR1 in Arabidopsis or transient overexpression of MnERF/ABR1 in mulberry leaves can significantly enhance its resistance to B. cinerea. Our results suggest that empty vector control (CK) has higher levels of malondialdehyde (MDA), a marker of oxidative stress, compared to overexpression lines. In contrast, the catalase (CAT) activity of overexpression lines was higher than that of CK plants. Furthermore, staining with 3,3′-diaminobenzidine (DAB) and nitro blue tetrazolium (NBT) indicated that the resistance to B. cinerea was more pronounced in plants with overexpression than in those of the CK plants. These findings uncovered the molecular regulatory pathway involving MnERF/ABR1 in response to B. cinerea and established a basis for the development of disease-resistant mulberry varieties through genome editing. Full article

Botrytis cinerea, the causal agent of gray mold disease, is a major phytopathogen responsible for substantial losses in horticultural crops. In this study, cultivation conditions for Bacillus velezensis R22 were optimized to maximize overall antifungal activity against B. cinerea. A Plackett–Burman design was used to identify medium components affecting antifungal activity in flask cultures, followed by response surface methodology based on a central composite design (CCD) to optimize sucrose concentration, temperature, and agitation speed in a stirred bioreactor. Maximum antifungal activity was obtained at 17.45 g/L initial sucrose, 31.8 °C, and 293 rpm. The biological relevance of the optimized culture was confirmed in a tomato infection model, in which gray mold severity was reduced by 85.3% relative to the untreated control and by 59.9% relative to the non-optimized R22 culture. The same CCD approach was subsequently applied to determine cultivation conditions that maximize the concentration of R22 viable cells. The optimal parameters for 24-h growth (35.46 g/L sucrose, 36.5 °C, and 454 rpm) differed markedly from those identified for maximal antifungal activity. When evaluated on uninfected tomato plants, cultures produced under conditions favoring higher cell density showed enhanced plant growth-promoting activity compared to the non-optimized culture. Mass spectrometric analysis of lipopeptide extracts revealed that the enhanced antifungal activity was accompanied by an increased abundance of long-chain homologs across all major lipopeptide families, particularly surfactins. Thus, our results indicate that maximizing overall antifungal activity may be of greater practical significance than optimization of the individual fungicidal agent. Full article

Phytopathogenic fungi cause major agricultural losses worldwide. Their control relies largely on synthetic fungicides, which raise concerns related to environmental impact, resistance development, and human health. Botanical extracts represent a promising, sustainable alternative, and members of the Brassicaceae family are recognized as rich sources of antifungal metabolites. In this study, the antifungal activity of ethanol extracts from Brassica napus and Capsella bursa-pastoris was evaluated against Botrytis cinerea, Colletotrichum acutatum, and Fusarium oxysporum, which are major phytopathogens widely recognized for causing significant diseases in diverse commercial crops worldwide. Antifungal effects on mycelial radial growth and conidial production were assessed in vitro using the amended culture medium assay. Extracts were chemically characterized by LC-DAD-ESI-MS, and a single-Y orthogonal partial least squares (OPLS) analysis was applied to integrate chemical and bioactivity data to identify metabolites associated with antifungal activity. Test botanical extracts showed organ- and pathogen-dependent antifungal activity. B. napus was more active, as seeds reduced B. cinerea growth, and roots strongly suppressed conidiation and inhibited F. oxysporum. In contrast, C. bursa-pastoris was less effective, with only the flower and fruit extracts causing modest reductions in F. oxysporum, while the other extracts were largely inactive. Fourteen metabolites were tentatively identified based on UV-Vis and mass spectral data. Among them, one flavanol and two indole-containing compounds were statistically correlated with antifungal activity, were subsequently isolated, and were structurally confirmed by NMR spectroscopy. These compounds (1–3) exhibited reasonable antifungal activity (IC₅₀ < 40 µM). The integrative covariate-based metabolic profiling approach proved operative for identifying bioactive constituents in the test botanical extracts, supporting the potential of Brassicaceae-derived extracts and their metabolites as natural antifungal agents. Full article

Peanut (Arachis hypogaea L.) production faces persistent threats from various infectious diseases. Planting healthy varieties with robust botanical defense networks is critical for minimizing future costs. Non-expressor of pathogenesis-related (NPR) regulators are involved in immune activation and act as key targets for deeper stress adaptation, and are thus promising targets for genetic enhancement. In this study, we characterized the peanut NPR4B protein and demonstrated its local subcellular binding to the nucleus. Ectopic overexpression of AhNPR4B in Arabidopsis thaliana significantly enhanced resistance to the necrotrophic pathogen Botrytis cinerea and enhanced cold tolerance, as supported by quantitative and statistical analyses (p < 0.05). As regards underlying molecular events, Y2H (Yeast 2-Hybrid) analysis revealed a binding in vitro physical relation of AhPR2-like to AhNPR4B. This binding was demonstrated in vivo through BiFC (Bimolecular Fluorescence Complementation). These results suggest that the AhNPR4B-AhPR2-like complex may act as a key regulatory module associated with biotic and abiotic stress signaling, potentially contributing to broad-spectrum stress resistance. These findings provide foundational insights into the functional roles of AhNPR4B and its interaction with AhPR2-like in regulating stress resistance and support its potential as a candidate target for future genetic improvements to enhance stress resilience in peanuts. Full article

Botrytis cinerea is a globally distributed phytopathogenic fungus that causes gray mold in eucalyptus seedlings, posing a severe threat to eucalyptus nursery production. Pseudomonas eucalypticola Liu et al. NP-1 is an endophytic bacterium isolated from eucalyptus with broad-spectrum antifungal activity. In this study, the fermentation broth extract of strain NP-1 was prepared using the organic solvent extraction method. The inhibitory effects, antifungal mechanisms, and biocontrol efficacy of the extract against B. cinerea were investigated. The results suggested that the NP-1 extract effectively inhibited mycelial growth, conidial germination, and germ tube development of B. cinerea. The EC₅₀ and EC₉₀ values for mycelial inhibition were 110 μg/mL and 332 μg/mL, respectively, while those for conidial germination inhibition were 126 μg/mL and 310 μg/mL. Microscopic and ultramicroscopic observations indicated that while the mycelial structures in the control and EC₅₀ groups remained intact, the EC₉₀ treatment significantly was associated with protoplasmic aggregation, leakage, and cavitation, suggesting potential structural damage to the fungal cells. In vitro and in vivo biocontrol assays showed that the control efficacy against gray mold reached 90.0% on detached eucalyptus leaves and 93.3% on eucalyptus seedlings. These findings elucidate the biocontrol potential of NP-1 and lay a foundation for the development of bio-based pesticides. Full article

Safflower (Carthamus tinctorius L.) is an economically important crop, yet its production is severely threatened by fungal diseases including Botrytis cinerea. The molecular mechanism underlying disease resistance in safflower remains largely unclear. Extracellular vesicles (EVs), as vital carriers for cross-kingdom communication and transport, play crucial roles in plant antifungal defense. Lipid transfer proteins (LTPs), members of the pathogenesis-related protein 14 family, have also been shown to be key players in plant disease resistance. The promising resistance-related candidate gene CtLTP8 was previously identified via genome-wide association study (GWAS). In this study, a genome-wide analysis of the LTP gene family in safflower was performed. EVs were isolated from the apoplastic washing fluid of B. cinerea-infected safflower leaves, and proteomic analysis was performed. Numerous proteins associated with disease resistance, including CtLTP8, were detected by proteomic profiling. CtLTP8 was found to be present in EVs through molecular biological experiments. Moreover, stable overexpression of CtLTP8 in safflower significantly increased resistance to B. cinerea. In summary, this study characterized the disease resistance-related proteome of safflower EVs, and verified the presence of CtLTP8 in EVs and its antifungal function, providing valuable gene resources and theoretical support for safflower disease-resistance breeding and research on EV-mediated plant immune mechanisms. Full article

Botrytis cinerea is a major phytopathogen responsible for significant postharvest losses in plant-derived foods. The increasing resistance to synthetic fungicides has driven the search for sustainable alternatives, including enzyme-based biofungicides. In this study, the proteolytic fraction P1G10 from Vasconcellea pubescens latex was encapsulated in an alginate–chitosan (ALG-CS) matrix to improve its stability and antifungal performance. The encapsulated formulation (ALG-CS-P1G10) retained ~95% enzymatic activity after 8 h under stress conditions (37 °C, 1350 lux), compared with 67% for the free enzyme. In vitro assays demonstrated a dose-dependent inhibition of B. cinerea growth, with an IC₅₀ value of ~11 mg/mL determined using a logistic model. At this concentration, the formulation reduced fungal adhesion by more than 80% and increased sensitivity to cell wall-disrupting agents (Congo Red and Calcofluor White), pointing to alterations in cell wall integrity. Importantly, the encapsulated system provided a more stable and sustained antifungal effect, consistent with a controlled-release mechanism. These results demonstrate that coupling enzyme stabilization with controlled release can improve the functional performance of protease-based antifungal systems, offering a promising strategy for the development of biofungicides in postharvest applications. Full article

Plant hormones and their synthetic analogueues offer sustainable alternatives for crop protection, yet the direct antifungal activity of strigolactone (SL) and its analogues against necrotrophic pathogens remain largely unexplored. Here, we screened eight phytohormones and related analogues for treatments of Botrytis cinerea and identified the SL analogue rac-GR24 (racemic GR24) as a concentration-dependent growth inhibitor active at low micromolar concentrations. Given the stereochemical complexity of SLs and their analogues, we evaluated multiple enantiopure isomers and found that ent-5DS and GR24^ent-5DS, which differ in configuration from natural SLs, exhibited the strongest inhibitory activity. This stereospecific response was further validated using another filamentous fungus, Sclerotinia sclerotiorum, which displayed an identical susceptibility profile. Combinatorial treatments with enantiopure isomers and double-concentration rac-GR24 revealed that the antifungal effect of the racemate is primarily attributable to the GR24^ent-5DS enantiomer, whereas the opposite enantiomer GR24^5DS is almost inactive. Collectively, our findings uncover a stereospecific response in fungal pathogens, demonstrating that B. cinerea and S. sclerotiorum respond to exogenous SL analogues in a chirally selective manner. This work establishes a stereochemically defined framework for developing enantioselective fungicidal agents with potential applications in sustainable agriculture. Full article

Papain-like cysteine proteases (PLCPs) are central immune hubs frequently targeted by pathogen effectors. Sugarcane smut, caused by Sporisorium scitamineum, threatens global sugarcane yield, yet effector manipulation of host PLCPs remains unclear. Genome-wide analysis of Saccharum spontaneum AP85-441 identified 61 PLCP-encoding genes, which were classified into nine conserved subfamilies. Among these, ScRD21A, a member of the RD21 subfamily, was prioritized for functional characterization. Two Pit2 homologs, SsPit2A and SsPit2B, were identified from S. scitamineum. Yeast two-hybrid, BiFC and pull-down assays demonstrated that both effectors interact with ScRD21A, and that this interaction depends on a conserved LXRR motif within their PID14-like region. In total protein extracts from Nicotiana benthamiana, co-expression of SsPit2A or SsPit2B reduced ScRD21A-associated cysteine protease activity. Transient expression of ScRD21A enhanced flg22-induced ROS production, attenuated Pst DC3000-induced hypersensitive response-associated necrosis, and increased resistance to Botrytis cinerea. Together, these results support a conserved PLCP-targeting strategy in smut fungi and identify the ScRD21A–SsPit2A/B module as a tractable framework for studying effector–protease interactions relevant to sugarcane smut. Full article

The potential of methanolic extracts from jara (Barkleyanthus salicifolius) and pomegranate carpel membranes (Punica granatum) as biological alternatives for the control of phytopathogenic fungi was evaluated against pathogens associated with commercially important crops in the Ciénega de Chapala region. Extracts were assessed in vitro against Botrytis cinerea and Rhizoctonia solani (strawberry), Curvularia sp., Pestalotiopsis sp., and Fusarium oxysporum (blackberry), Pythium sp. and Fusarium sp. (tomato), and Sclerotium rolfsii (onion). Antifungal bioassays demonstrated that the B. salicifolius extract inhibited the mycelial growth of R. solani, whereas the pomegranate extract inhibited seven of the eight species tested, with the exception of S. rolfsii. Phytochemical screening revealed the presence of alkaloids, flavones, flavonols, chalcones, and quinones in pomegranate, and flavones, flavonols, alkaloids, and sterols in jara. Additionally, phytol and caryophyllene were identified in the latter via GC–MS. Full article