Search Results (48)

Phytopathogenic fungi that affect postharvest are a serious problem for agriculture, so this research explores the antifungal potential of three different “rosemary” species growing in Chile through in vitro and in silico assays. The analysis of essential oils (GC/MS) reveals the dominant constituents of Salvia rosmarinus (camphor: 66.96%), Baccharis linearis (lachnophyllum ester: 88.62%) and Fabiana imbricata (an oxygenated sesquiterpene: 43.66%) and shows profiles that differ from chemotypes of the same species from other areas of the world. B. linearis oil was shown to be a versatile antifungal substance, inhibiting Botrytis cinerea and Monilinia fructicola at moderate concentrations; F. imbricata oil stood out as a major inhibitor of mycelial growth of the same isolate of M. fructicola used to test B. linearis oil (EC₅₀ of 15.86 + 0.67 µg/mL) and completely inhibited of its conidial germination. In silico assays confirmed the complexity of interactions of F. imbricata sequiterpenoids with catalytic sites of succinate dehydrogenase and catalase 2, key enzymes in mycelial growth and in maintaining redox homeostasis in the early development of M. fructicola, respectively. The results of this research make F. imbricata a good candidate for the development of a formulation applicable in vivo as an eco-friendly post-harvest antifungal agent. Full article

The antifungal activity of natural extracts, essential oils (EOs), and pure volatiles against Monilinia fructicola, the main causal agent of brown rot of stone fruits, was evaluated in in vitro tests. Cinnamon (CI), lemongrass (LE), geraniol (GE), and myrrh (MY) EOs were the most effective antifungal agents and, hence, selected as ingredients of composite edible coatings (CECs) formulated with hydroxypropyl methylcellulose (HPMC) and lipidic components. In in vivo curative experiments with ‘Black Gold’ plums artificially inoculated with M. fructicola and incubated for up to 10 days at 20 °C, brown rot incidence was reduced by up to 49% with CECs containing 4 g/kg LE, 2 g/kg GE, or 5 g/kg MY. These CECs were then evaluated for brown rot control and quality maintenance of ‘Angeleno’ plums stored for up to 6 weeks at 1 °C and 90% RH, followed by a shelf-life period of 4 days at 20 °C. After 3 weeks, CECs containing GE and MY reduced brown rot incidence by 45 and 70%, respectively. After 6 weeks plus shelf life, all CECs reduced brown rot severity (lesion size) by 30–50%. Regarding fruit quality, coated plums showed higher firmness than uncoated control plums, and the CEC containing GE significantly reduced weight loss after 6 weeks plus shelf life. Moreover, physicochemical quality attributes (titratable acidity, soluble solids content, and volatile compounds) and sensory properties (overall flavor, off-flavor, firmness, and external appearance) of coated plums were not negatively affected by CEC application. Furthermore, all coated plums exhibited more gloss than uncoated fruit. Overall, the CEC-GE formulation was the most effective in reducing decay and maintaining the postharvest quality of cold-stored plums, showing the best potential as a sustainable alternative for plum postharvest preservation. Full article

Extreme environments are a largely unexplored reservoir of microbial diversity, with a remarkable potential to be exploited in agriculture. One hundred and seventeen yeast isolates, derived from different ecosystems in Italy, Sweden, Algeria, and France, were molecularly identified, and the most represented genus was Aureobasidium (57%). A phylogenetic analysis based on a multi-locus sequence typing (ITS, ELO, EF-1alpha) was conducted to characterize the black yeasts’ population. To investigate A. pullulans extremophilic and extremotolerant behaviour, different temperatures and pH, together with the enzymatic production, were evaluated. The strains were tested by in vitro and in vivo assays against the postharvest fungal pathogen Monilinia fructicola as potential biocontrol agents (BCAs). Results displayed a great ecological variability concerning strains’ growth and cell production depending on different culture conditions. However, a remarkable thermotolerance aptitude was detected in almost all the strains. In particular, the strains belonging to Group 2 (Algerian Desert) and 3 (Alto Adige Region) showed, respectively, higher thermotolerance and biocontrol ability. These findings showed how some extreme environments could represent a promising source for new potential BCAs. However, further studies are needed to investigate the mechanisms of action of these putative BCAs for application during the postharvest phase. Full article

Argemone mexicana L. is considered a weed; however, it contains secondary metabolites that can control phytopathogenic fungi in vitro, with the potential to adapt its effectiveness in the field. In the present study, leaf extracts of A. mexicana (hexane and methanol) were prepared, and their chemical profiles were analyzed using gas chromatography–mass spectrometry (GC-MS). The in vitro antifungal activity of each extract was evaluated at different concentrations (500, 1000, 2000, 4000, and 8000 mg L⁻¹) against phytopathogens such as Monilinia fructicola, Colletotrichum gloeosporioides, Fusarium oxysporum, and Sclerotinia sclerotiorum. Based on their chemical profiles, 14 compounds were identified in the hexanic extract, and 11 compounds were identified in the methanolic extract. These compounds included those with antifungal activity, such as Benzene; 1.3-bis(1.1-dimethylethyl)-; pentanoic acid; 5-hydroxy-, 2,4-di-1-butylphenyl esters; 1,2,4-Triazol-4-amine; and N-(2-thienylmethyl). The hexanic extract demonstrated fungistatic activity on the four fungi tested, while the methanolic extract exhibited fungicidal activity against C. gloeosporioides and F. oxysporum. The results of the Probit analysis showed variations in the sensitivity of phytopathogenic fungi to the treatments evaluated. In M. fructicola, the hexane extract presented an EC₅₀ of 317,146 mg L⁻¹ and an EC₉₀ of 400,796 mg L⁻¹. For C. gloeosporioides, the EC₅₀ was 2676 mg L⁻¹ and the EC₉₀ was 888,177 mg L⁻¹, while in F. oxysporum an EC₅₀ of 34,274 mg L⁻¹ and an EC₉₀ of 1528 mg L⁻¹ were estimated. In the case of S. sclerotiorum, an EC₅₀ of 560 mg L⁻¹ and an EC₉₀ of 7776 mg L⁻¹ were obtained. Finally, for the commercial fungicide Captan^®, an EC₅₀ of 1.19 mg L⁻¹ and an EC₉₀ of 1.67 mg L⁻¹. These results suggest that extracts from A. mexicana could provide a natural alternative for the control of phytopathogenic fungi. Full article

Postharvest fungal rot causes significant economic losses in the agroindustry. Current control methods involving the use of synthetic fungicides are becoming increasingly ineffective and pose environmental risks. This necessitates exploring sustainable alternatives, such as essential oils derived from medicinal plants, to achieve safer and effective disease control. This research examined the chemical composition and efficacy of essential oils from Aloysia citriodora, Aloysia polystachya and their compounds against the postharvest rot fungi Monilinia fructicola, Monilinia laxa, and Botrytis cinerea. The main compounds of essential oils were analyzed by GC/MS and revealed differences in their composition. A. citriodora is characterized by the presence of spathulenol and caryophyllene oxide. In contrast, A. polystachya is characterized by the predominance of carvone. The results show that the essential oil of A. citriodora and the compound farnesol are able to inhibit the three pathogens. Notably, against M. fructicola, the EC₅₀ values were 61.89 μg/mL and 72.18 μg/mL, respectively. Against B. cinerea, the EC₅₀ values were 85.34 μg/mL and 47.6 μg/mL. Molecular docking also showed that farnesol has affinity for the enzyme succinate dehydrogenase suggesting a possible mechanism of action. This compound and A. citriodora essential oil show potential in the control of phytopathogens. Full article

Gray mold (Botrytis cinerea) and brown rot (Monilinia fructicola) are devastating diseases in stone fruit production. In this work, a series of 3-acyl-6-bromoindoles, including six new compounds, were synthesized via green and efficient microwave-assisted methodology to evaluate their antifungal potential. Bioassays revealed a remarkable duality in the compounds’ mechanism of action. The starting material, 6-bromoindole (I), proved to be a highly potent inhibitor of mycelial growth, with a remarkable EC₅₀ of 11.62 µg/mL against B. cinerea and 18.84 µg/mL against M. fructicola, surpassing BC-1000^® and Captan^® and comparable to Mystic^®. Conversely, compound I was ineffective at inhibiting conidial germination. In stark contrast, the simple acetylated derivative 3-acetyl-6-bromoindole (II) emerged as a formidable inhibitor of spore germination, achieving 100% inhibition for B. cinerea and 96% for M. fructicola, outperforming several controls. This suggests that, while compound I is effective against established infections, compound II acts as a powerful preventative agent against initial spore-based propagation. The antifungal activity of the compounds directly correlates with their ability to bind to the enzymes SDH and MfCat2, the latter being the main mechanism of action. These findings highlight the potential of developing specialized fungicides from the 6-bromoindole scaffold, targeting different stages of fungal development. Full article

Brown rot, caused by Monilinia species, is a major disease affecting stone and pome fruits. The most relevant species are M. fructigena, M. laxa, M. polystroma, and M. fructicola. These four species exhibit morphological differences, but comparative data on these traits remain limited. In European integrated fruit production, pre-harvest control of brown rot mainly relies on the fungicides cyprodinil, boscalid, and tebuconazole. Given the coexistence of multiple Monilinia species, understanding differences in fungicide sensitivity is crucial for optimizing control strategies. In this study, mycelial growth, colony and conidial morphology, and sporulation capacity on potato dextrose agar (PDA), tomato sauce agar (TSA), and apple fruit were investigated. Fungicide sensitivity was assessed by measuring mycelial growth on apples following treatment with the three active ingredients. Tebuconazole was the most effective fungicide, particularly against M. laxa and M. polystroma, while cyprodinil and boscalid were less effective. These results highlight the need for species-specific fungicide strategies, Monilinia populations, and the effectiveness of disease control under various environmental conditions. All Monilinia species sporulated successfully on TSA, underscoring its suitability for sporulation studies. Conidial size varied significantly among species; nevertheless, overlapping sizes prevent reliable species or strain discrimination based on this trait alone. Full article

Molecules containing indole cores are of interest due to their multiple biological applications and seem to be an alternative to face contemporary challenges in agriculture, especially the control of phytopathogens that affect fruit quality. In this research, starting from 5-bromoindole (A), eleven 3-acyl-5-bromoindole derivatives with linear (B–G) and aromatic (H–L) substitutions were obtained through microwave-assisted synthesis. The antifungal capacity of indole, 5-bromoindole (A) and their derivatives (B–L) were determined by in vitro assays on Monilinia fructicola and Botrytis cinerea, and a molecular docking was performed on mitochondrial complex II, succinate dehydrogenase (SDH). The results indicate that compounds A, B, G, and L were able to inhibit the growth of M. fructicola, while only A and J showed activity against B. cinerea. The acylation of A improved their ability to inhibit the germination of conidia on both pathogens. Compounds A, B and G are the most promising candidates for future research due to their inhibition on M. fructicola and/or B. cinerea and demonstrate favorable binding energies with SDH. Full article

Plant viruses have been traditionally considered pathogens restricted to plant hosts. However, recent studies have shown that some plant viruses can infect and replicate in filamentous fungi and oomycetes, suggesting that their host range is broader than previously thought, and that their ecological interactions are more complex. In this study, we investigated the ability of the well-characterized positive-sense RNA plant virus Tobacco mosaic virus (TMV) to replicate in four major phytopathogenic fungi from different taxonomic groups: Botrytis cinerea, Fusarium oxysporum f. sp. lycopersici, Verticillium dahliae, and Monilinia fructicola. Using a recombinant TMV-based vector expressing a green fluorescent protein (TMV-GFP-1056) as reporter, we demonstrated that TMV can enter, replicate, and persist within the mycelia of B. cinerea and V. dahliae—at least through the first subculture. However, it cannot replicate in F. oxysporum f. sp. lycopersici and M. fructicola. RNA interference (RNAi) is a conserved eukaryotic epigenetic mechanism that provides an efficient defence against viruses. We explored the role of RNAi in the interaction between TMV and the mycelia of V. dahliae and B. cinerea. Our results revealed a strong induction of the Dicer-like 1 and Argonaute 1 genes, which are key compounds of the RNA silencing pathway. This RNAi-based response impaired TMV-GFP replication in both fungi. Notably, despite viral replication and RNAi activation, the virulence of V. dahliae and B. cinerea on their respective host plants remained unaffected. These findings reinforce the emerging recognition of cross-kingdom virus transmission and interactions, which likely play a crucial role in pathogen ecology and viral evolution. Understanding these virus–fungus interactions not only sheds light on RNAi interference silencing mechanisms but also suggests that plant viruses like TMV could serve as simple and effective tools for functional genomic studies in fungi, such as in V. dahliae and B. cinerea. Full article

This study introduces an innovative strategy for active, biodegradable food packaging through the incorporation of gamma-decalactone (GDL), a natural aromatic compound with antimicrobial properties, into apple-pectin-based edible films. The addition of GDL significantly modified the film structure, resulting in enhanced light barrier properties (the opacity increased from 1.10 to 8.64 a.u./mm), a more porous microstructure (confirmed by SEM), and reduced tensile strength (from 13.84 to 5.68 MPa). The films also exhibited lower water vapour sorption (from 1.45 to 0.80 g/g dry matter (d.m.) and increased gas permeability. FTIR analysis confirmed interactions between GDL and the polymer matrix. The films with GDL added exhibited antimicrobial properties against various microbial species, such as bacteria, yeasts, and moulds. A 5% addition of GDL to the coating completely inhibited the growth of Bacillus subtilis bacteria and Yarrowia lipolytica, reducing the number of yeast cells by 3 log units (after 48 h of culture, from 7.11 ± 0.09 to 4.09 ± 0.27 log CFU/mL) and limiting Monilinia fructicola mycelium growth by 70%. These results highlight GDL’s dual function as a natural aromatic and antimicrobial agent, supporting its potential application in sustainable packaging for perishable foods. Full article

Monilinia fructicola causes brown rot on a wide variety of stone fruits, causing several losses in the field and during storage of fruits. Due to the diverse biological activity of chalcones and their derivatives, they have emerged as a promising alternative for controlling phytopathogenic fungi. The aim of this study was to synthesize 3′,4′-methylenedioxychalcone derivatives and evaluate their in vitro inhibitory effect on mycelial growth and the conidial germination of M. fructicola. Additionally, a molecular docking study and the prediction of lipophilicity were carried out to investigate their chemical behavior. The results showed that compound F exhibited the most potent antifungal activity, with EC₅₀ and MIC values of 20.61 µg/mL and <10 µg/mL for mycelial growth and conidial germination, respectively, presenting an adequate lipophilicity (Log p values = 2.79), which would allow proper diffusion through the fungal cell membrane. The in silico study revealed a great number of interactions between compound F and the different active sites of the succinate dehydrogenase enzyme, suggesting a favorable interaction with a binding energy score value of −6.9 kcal/mol, similar to CBE, the native ligand of this enzyme. These types of compounds could provide preventive protection in various stone and other crops. Full article

To carry out this work, latex from Ficus carica was obtained for the production of coatings, the characteristics of the produced coatings were analyzed, and their application on dried figs was evaluated. Work was conducted to obtain latex and produce coatings, optimizing the mixture and determining its properties. Additionally, the shelf life of coated fruits was studied. The results showed that the coatings had a milky white color, a thickness between 0.04 mm and 0.09 mm, a moisture content close to 25%, and a water solubility ranging from 80% to 98.73%. The 10% latex coatings showed better elasticity and resistance, being selected for the shelf life study. The optimal formulations selected were 28, 29, and 31, all with 10% latex. These coatings exhibited interesting antimicrobial activities against bacteria Escherichia coli, Staphylococcus aureus, and Salmonella choleraesuis and antifungal activity against Botrytis cinerea, Penicillium expansum, Aspergillus flavus, and Monilinia fructicola. When applied to dried figs, it was observed that the appearance of the figs did not visibly change. Antioxidant activity was highest in batch 28, which also showed less microbiology and lower hardness at 60 days. Thus, coatings not only helped maintain the natural color of the fruits but also preserved their freshness and overall quality for a longer period. This makes them an effective and sustainable solution for the food industry. Full article

Monilinia spp., which causes brown rot, is one of the most damaging pathogens in stone fruits. Researchers are exploring epiphytic and endophytic microorganisms with the potential to suppress pathogens, control pathogenic microorganisms, and/or promote plant growth. In this study, microorganisms with antagonistic activity against three Monilinia species were isolated from plum orchard soil and plum fruits. Antagonism tests in vitro showed strong antagonistic properties of six strains of bacteria and two yeast-like fungi against M. fructigena, M. fructicola, and M. laxa, with growth inhibition from 45.5 to 84.6%. The antagonists were identified and characterized at the genetic level using whole genome sequencing (WGS). Genes involved in antibiotic resistance, virulence, secondary metabolite synthesis, and plant growth promotion were identified and characterized through genome mapping, gene prediction, and annotation. None of the microorganisms studied were predicted to be pathogenic to humans. The results of this study indicate that the bacteria Bacillus pumilus, B. velezensis, two strains of Lysinibacillus agricola, Pseudomonas chlororaphis isolated from stone fruit orchard soil, and the yeast-like fungus Aureobasidium pullulans, isolated from plums, are promising candidates for the biological control of Monilinia spp. Full article

Monilinia fructicola is the most common and destructive brown rot agent on peaches. Knowledge of gene expression mediating host–pathogen interaction is essential to manage fungal plant diseases. M. fructicola putative virulence factors have been predicted by genome investigations. The pathogen interaction with the host was validated. Five M. fructicola isolates were inoculated on two cultivars (cv.s) of peach (Prunus persica (L.) Batsch) ‘Royal Summer’ and ‘Messapia’ with intermediate and late ripening periods, respectively. The expression pattern of 17 candidate effector genes of M. fructicola with functions linked to host invasion and fungal life, and seven peach genes involved in the immune defense system were monitored at 0, 2, 6, 10, and 24 h-post inoculation (hpi). All fungal isolates induced similar brown rot lesions on both cv.s whereas the modulation of effector genes was regulated mainly at 2, 6, and 10 hpi, when disease symptoms appeared on the fruit surface, confirming the involvement of effector genes in the early infection stage. Although differences were observed among the fungal isolates, the principal component investigation identified the main differences linked to the host genotype. The salicylic acid and jasmonate/ethylene signaling pathways were differently modulated in the host independent from the fungal isolate used for inoculation. On plants susceptible to brown rot, the pathogen may have adapted to the host’s physiology by modulating its effectors as weapons. Full article

Fruit rots caused by filamentous fungi such as Monilinia fructicola and Monilinia laxa have a strong impact on crop yield and fruit commercialization, especially as they affect a wide variety of stone fruits. The antifungal efficacy of benzylidene-cycloalkanones has been previously described in in vitro assays against M. fructicola; so, this study aims to evaluate the in vivo inhibitory potential of these hybrids on fruits that have been inoculated with M. fructicola, and use molecular docking to visualize the main interactions of these molecules in the active site of the enzyme succinate dehydrogenase (SDH). The results indicate that compound C achieves the highest inhibition of both Monilinia species (15.7–31.4 µg/mL), spore germination in vitro (<10 µg/mL), and has promising results in vivo, without causing phytotoxicity in fruits. The results from molecular docking suggest that hydroxyl groups play a crucial role in enhancing the binding of compound C to SDH and contribute to the formation of hydrogen bonds with amino acid residues on the enzyme active site. Full article