Search Results (45)

Honey bees (Apis mellifera ligustica) are essential pollinators in both ecosystems and agricultural production. However, their populations are declining due to various factors, including pesticide exposure. Despite their importance, the reproductive castes, particularly drones, remain understudied in terms of pesticide effects. To investigate the effects of azoxystrobin and picoxystrobin on honey bee drones, the drones were exposed to different concentrations of azoxystrobin and picoxystrobin for 14 days; the drone survival, body weight, nutrient content, reproductive organs, and sperm concentration were assessed. Results showed that exposure to both fungicides caused a significant reduction in drone survival rates, with survival rates decreasing progressively as the duration of exposure increased. Compared to the control group, the body weights of drones in all treatment groups were significantly lower on days 7 and 14. Nutrient analysis revealed that low concentrations of azoxystrobin and picoxystrobin increased protein levels, while free fatty acid content decreased significantly in all treatment groups. No significant changes were observed in the total carbohydrate content. Morphological examination of reproductive organs showed that the lengths of the mucus glands and seminal vesicles in drones were significantly shorter in the treatment groups compared to the control group. Furthermore, exposure to azoxystrobin and picoxystrobin resulted in a significant decline in sperm concentration in the drones. These findings indicate that azoxystrobin and picoxystrobin have adverse effects on the health and reproductive capacity of honey bee drones. The present study highlights the need to reassess the risks posed by these fungicides to pollinators, particularly given the critical role of drones in maintaining the genetic diversity and resilience of honey bee colonies. Further research is warranted to elucidate the underlying mechanisms of these effects and explore potential mitigation strategies. Full article

This study describes the development, characterization and in vitro evaluation of poly(ε-caprolactone) (PCL) nanoparticles loaded with xanthyletin for the control of Atta sexdens rubropilosa through the inhibition of its symbiotic fungus Leucoagaricus gongylophorus. Nanoparticles were prepared via interfacial polymer deposition, with formulation NC5 selected based on optimal physicochemical properties. NC5 exhibited an encapsulation efficiency of 98.0%, average particle size of 304 nm and zeta potential of −29.3 mV. Scanning electron microscopy confirmed spherical morphology and the absence of crystalline residues. The formulation remained physically stable for four months at 4 °C. In vitro release showed biphasic behavior, with an initial burst followed by sustained release. Under UV exposure, NC5 enhanced xanthyletin photostability by 15.4-fold compared to the free compound. Fungicidal assays revealed 76% inhibition of fungal growth with NC5, compared to 85% with free xanthyletin. These results support the potential application of xanthyletin-loaded PCL nanoparticles as a stable and controlled delivery system for the biological control of leaf-cutting ants by targeting their fungal mutualist. Further in vivo studies are recommended to assess efficacy under field conditions. Full article

The proliferation of toxigenic fungi in food and the subsequent production of mycotoxins constitute a significant concern in the fields of public health and consumer protection. This review highlights recent strategies and emerging methods aimed at preventing fungal growth and mycotoxin contamination in food matrices as opposed to traditional approaches such as chemical fungicides, which may leave toxic residues and pose risks to human and animal health as well as the environment. The novel methodologies discussed include the use of plant-derived compounds such as essential oils, classified as Generally Recognized as Safe (GRAS), polyphenols, lactic acid bacteria, cold plasma technologies, nanoparticles (particularly metal nanoparticles such as silver or zinc nanoparticles), magnetic materials, and ionizing radiation. Among these, essential oils, polyphenols, and lactic acid bacteria offer eco-friendly and non-toxic alternatives to conventional fungicides while demonstrating strong antimicrobial and antifungal properties; essential oils and polyphenols also possess antioxidant activity. Cold plasma and ionizing radiation enable rapid, non-thermal, and chemical-free decontamination processes. Nanoparticles and magnetic materials contribute advantages such as enhanced stability, controlled release, and ease of separation. Furthermore, this review explores recent advancements in the application of artificial intelligence, particularly machine learning methods, for the identification and classification of fungal species as well as for predicting the growth of toxigenic fungi and subsequent mycotoxin production in food products and culture media. Full article

Phytopathogenic fungi are important causative agents of many plant diseases, resulting in substantial economic losses in agriculture. Proteomics has become one of the most relevant high-throughput technologies, and current advances in proteomic methodologies have been helpful in obtaining massive biological information about several organisms. This review outlines recent advances in mass spectrometry-based proteomics applied to the study of phytopathogenic fungi, including analytical platforms such as LC-MS/MS and MALDI-TOF, as well as quantitative strategies including TMT, iTRAQ, and label-free quantification. Key findings are presented from studies exploring infection-related protein expression, virulence-associated factors, post-translational modifications, and fungal adaptation to chemical fungicides, antimicrobial peptides, and biological control agents. Proteomic analyses have also elucidated mechanisms of resistance, oxidative stress response, and metabolic disruption following exposure to natural products, including essential oils and volatile organic compounds. The proteomic approach enables a comprehensive understanding of fungal biology by identifying proteins related to pathogenicity, stress adaptation, and antifungal resistance, while also facilitating the discovery of molecular targets and natural compounds for the development of sustainable antifungal strategies that reduce risks to human health and the environment. Full article

Diaporthe species are critical plant pathogens that contribute to a disease complex responsible for substantial yield losses in soybean production worldwide. However, reports on the primary Diaporthe species causing soybean stem blight and their sensitivity to various fungicides are scarce in China. In this study, a total of 46 D. longicolla strains were isolated and identified from diseased soybean stems and rots collected from 14 regions of Heilongjiang province in 2021 and 2022. Among the eight fungicides examined, fludioxonil, mefentrifluconazole, tebuconazole, and azoxystrobin demonstrated effective inhibition for D. longicolla, with EC₅₀ values < 0.3 µg/mL. Interestingly, the EC₅₀ values of D. longicolla to two succinate dehydrogenase inhibitors (SDHIs), pydiflumetofen and fluopyram, were 5.47 µg/mL and over 100 µg/mL, respectively. In molecular dynamics simulations, pydiflumetofen exhibited a smaller RMSD, while fluopyram had a higher binding free energy with Sdh proteins compared to pydiflumetofen. This difference may contribute to the higher activity of pydiflumetofen in D. longicolla. Further analysis of the electrostatic potential and structural conformations of the binding pocket revealed that pydiflumetofen formed more hydrophobic interactions with SdhC and SdhD and was positioned closer to the SdhD subunit. A mixture of fludioxonil and mefentrifluconazole at a ratio of 1:5, as well as fludioxonil and pydiflumetofen at a ratio of 1:5, exhibited synergistic effects. These findings demonstrated that several fungicides could be utilized to control Diaporthe stem blight, and the difference in binding affinity to the Sdh subunit impacts sensitivity to fluopyram and pydiflumetofen. Full article

A total of 34 strains of bacteria were isolated from peanut rhizosphere soil, and all showed some in vitro inhibition of the pathogen Sclerotium rolfsii in co-culture. Strain YB-1632 produced the highest level of inhibition and also produced relatively high levels of biofilm in culture. Cell-free culture extracts and volatiles from it were also inhibitory to S. rolfsii. Based on 16S rDNA, gyrA, and gyrB sequences, it was identified as Bacillus siamensis. In the greenhouse, seed treatment resulted in a level of control of peanut sclerotium blight (PSB) comparable to that of a standard fungicide seed treatment. In addition to its antifungal activity, YB-1632 could induce disease resistance in peanut seedlings based on increasing peanut defense enzyme activities and gene expression. The priming of defense gene expression against a necrotrophic pathogen is consistent with Induced Systemic Resistance (ISR). In addition, YB-1632 produced enzyme activities in culture associated with root colonization and plant growth promotion. In the greenhouse, it increased peanut seedling growth, indicating the YB-1632 is a plant growth-promoting rhizobacterium (PGPR). In summary, YB-1632 is a promising novel PSB biocontrol agent and PGPR of peanut. Full article

The market demand for baby leaf lettuce is constantly increasing, while safety has become one of the most important traits in determining consumer preference driven by human health hazards concerns. In this study, the performance of visible and near-infrared (vis/NIR) spectroscopy was tested in discriminating pesticide-free against pesticide-treated lettuce plants. Two commercial fungicides (mancozeb and fosetyl-al) and two insecticides (deltamethrin and imidacloprid) were applied as spray solutions at the recommended rates on baby leaf lettuce plants. Untreated-control plants were sprayed with water. Reflectance data in the wavelength range 400–2500 nm were captured on leaf samples until harvest on the 10th day upon pesticide application, as well as after 4 and 8 days during post-harvest storage at 5 °C. In addition, biochemical components in leaf tissue were also determined during storage, such as antioxidant enzymes’ activities (peroxidase [POD], catalase [CAT], and ascorbate peroxidase [APX]), along with malondialdehyde [MDA] and hydrogen peroxide [H₂O₂] content. Partial least square discriminant analysis (PLSDA) combined with feature-selection techniques was implemented, in order to classify baby lettuce tissue into pesticide-free or pesticide-treated ones. The genetic algorithm (GA) and the variable importance in projection (VIP) scores identified eleven distinct regions and nine specific wavelengths that exhibited the most significant effect in the detection models, with most of them in the near-infrared region of the electromagnetic spectrum. According to the results, the classification accuracy of discriminating pesticide-treated against non-treated lettuce leaves ranged from 94% to 99% in both pre-harvest and post-harvest periods. Although there were no significant differences in enzyme activities or H₂O₂, the MDA content in pesticide-treated tissue was greater than in untreated ones, implying that the chemical spray application probably induced a stress response in the plant that was disclosed with the reflected energy. In conclusion, vis/NIR spectroscopy appears as a promising, reliable, rapid, and non-destructive tool in distinguishing pesticide-free from pesticide-treated lettuce products. Full article

Apple scab, caused by the pathogenic fungus Venturia inaequalis, can result in significant economic losses. The frequent use of fungicidal products has led to the emergence of isolates resistant to commonly used active substances. Therefore, biological control offers a sustainable alternative for managing apple scab. In this study, eight Trichoderma isolates were evaluated against five different isolates of V. inaequalis isolated from the Fes-Meknes region. The biocontrol potential of these Trichoderma isolates had previously been demonstrated against other pathogens. The results indicated that the inhibition rate of mycelial growth of V. inaequalis obtained with Trichoderma spp. isolates ranged from 50% to 81%, with significant differences observed among the pathogenic isolates after 5 and 12 days of incubation. In addition, the in vitro tests with Trichoderma cell-free filtrates showed inhibition rates ranging from 2% to 79%, while inhibition rates ranged from 5% to 78% for volatile compound tests. Interestingly, the inhibition of spore germination and elongation was approximately 40–50%, suggesting the involvement of antifungal metabolites in their biocontrol activities. The in vivo bioassay on detached apple leaves confirmed the biocontrol potential of these Trichoderma isolates and demonstrated their ability to preventively control apple scab disease. However, their efficacies were still lower than those of the fungicidal product difenoconazole. These findings could contribute to the development of an effective biofungicide based on these Trichoderma isolates for reliable and efficient apple scab control. Full article

The causal agent of tomato leaf mold, Cladosporium fulvum, is prevalent in greenhouses worldwide, especially under high humidity conditions. Despite its economic impact, studies on antifungal agents targeting C. fulvum remain limited. This study evaluates biocontrol agents (BCAs) as alternatives to chemical controls for managing this disease, alongside the strobilurin fungicide azoxystrobin. From a Moroccan collection of potential BCAs, five bacterial isolates (Alcaligenes faecalis ACBC1, Pantoea agglomerans ACBC2, ACBP1, ACBP2, and Bacillus amyloliquefaciens SF14) and three fungal isolates (Trichoderma spp. OT1, AT2, and BT3) were selected and tested. The in vitro results demonstrated that P. agglomerans isolates reduced mycelial growth by over 60% at 12 days post-inoculation (dpi), while Trichoderma isolates achieved 100% inhibition in just 5 dpi. All bacterial isolates produced volatile organic compounds (VOCs) with mycelial inhibition rates ranging from 38.8% to 57.4%. Likewise, bacterial cell-free filtrates significantly inhibited the pathogen’s mycelial growth. Greenhouse tests validated these findings, showing that all the tested isolates were effective in reducing disease incidence and severity. Azoxystrobin effectively impeded C. fulvum growth, particularly in protective treatments. Fourier transform infrared spectroscopy (FTIR) analysis revealed significant biochemical changes in the treated plants, indicating fungal activity. This study provides valuable insights into the efficacy of these BCAs and azoxystrobin, contributing to integrated management strategies for tomato leaf mold disease. Full article

Gray mold, caused by Botrytis cinerea Pers. Fr., is one of the most vital plant diseases, causing extensive pre- and post-harvest losses in apple fruits. In the current study, we isolated and identified two potential endophytic bioagents, Bacillus subtilis and Streptomyces endus. Both bioagents exhibited a potent fungistatic effect against B. cinerea under both in vitro and in planta conditions. Moreover, two experiments were carried out; (i) the first experiment was conducted at room temperature after artificial inoculation with B. cinerea to monitor the progression of the infection and the corresponding biochemical responses of the apples. Our in vivo findings showed that the treated B. cinerea-infected apple fruits with the cell-free bacterial filtrate of B. subtilis and S. endus (dipping or wrapping) significantly reduced the rotten area of the treated apple at room temperature. Additionally, B. subtilis and S. endus enhanced the enzymatic (POX and PPO) and non-enzymatic (phenolics and flavonoids) antioxidant defense machinery in treated apples. (ii) The second experiment focused on the preventive effects of both bioagents over a 90-day storage period at 1 °C of healthy apples (no artificial inoculation). The application of both bacterial filtrates prolonged the storage period, reduced the relative weight loss, and maintained high-quality parameters including titratable acidity, firmness, and total soluble solids of apple fruits under cold storage at 1 °C. The Kaplan–Meier analysis of rotten apples over 90 days during cold storage showed that the treated apples lasted longer than the non-treated apples. Moreover, the lifespan of apple fruits dipped in the culture filtrate of B. subtilis, or a fungicide, was increased, with no significant differences, compared with the non-treated apples. The current results showed the possibility of using both bioagents as a safe and eco-friendly alternative to chemical fungicides to control gray mold disease in apples. Full article

Citrus fruits stand as pivotal and extensively cultivated fruit crops on a global scale, boasting substantial economic and nutritional significance. Despite their paramount importance, citrus growers and the industry face a formidable obstacle in the form of post-harvest losses caused by plant pathogens. Effectively addressing this challenge has become imperative. The predominant approach to tackle these pathogens has traditionally involved the use of chemical fungicides. However, the escalating environmental concerns associated with chemical interventions, coupled with a growing consumer preference for pesticide-free produce, have catalyzed an earnest quest for alternative methods of disease control in the citrus industry. The antagonistic yeasts hold great promise as biocontrol agents for mitigating post-harvest fungal diseases in citrus. In this regard, this review summarizes the current state of knowledge regarding the study of yeast strains with biocontrol potential. Thus, the various modes of action employed by these yeasts and their effectiveness against prominent citrus pathogens such as Penicillium digitatum, Penicillium italicum and Geotrichum citri were discussed. Additionally, the review delved into the challenges associated with the practical implementation of yeast-based biocontrol strategies in citrus post-harvest management and investigated the potential of yeast-based approaches to enhance the safety and quality of citrus produce, while reducing the reliance on chemical fungicides and contributing to the sustainable and environmentally responsible future of the citrus industry. Full article

Decades of intensive use of copper-based fungicides against downy mildew in hops has led to considerable accumulation of copper in topsoil, resulting in toxic effects on plants. Due to its high sorption capacity, the application of co-composted biochar compost might reduce copper toxicity, whereby a synergistic effect of the composting process is supposed to occur. Furthermore, biochar addition might improve the composting process itself. Therefore, hop bines were co-composted without as well as with 5 and 20 vol% biochar, respectively. During composting, the temperature and concentration of O₂, CO₂, H₂S, CH₄ and NH₃ in the compost heaps were regularly recorded. The biochar-free compost as well as the two composts with the biochar addition were characterized with regard to their plant-growing properties and were mixed into soils artificially spiked with different amounts of copper as well as into copper-polluted hop garden and apple orchard soils. The respective soil without the compost addition was used as the control, and further treatments with biochar alone and in combination with biochar-free compost were included in a plant response test with Chinese cabbage. The biochar addition increased the temperature within the compost heaps by about 30 °C and extended the duration of the thermophilic phase by almost 30 days, resulting in a higher degree of hygienization. Furthermore, the application of co-composted biochar composts significantly improved plant biomass by up to 148% and reduced the copper concentration, especially of roots, by up to 35%. However, no significant differences in the biochar-free compost were found in the artificially copper-spiked soils, and the effect of co-composted biochar compost did not differ from the effect of biochar alone and in combination with biochar-free compost. Nevertheless, the co-composting of hop bines with biochar is recommended to benefit from the positive side effect of improved sanitization in addition to reducing copper toxicity. Full article

Legumes are indispensable crops in sustainable agricultural systems because of their capability for biological nitrogen fixation owing to symbiosis with rhizobia and soil fertility restoration. Fungal pathogens from the genera Fusarium cause rotting and wilting and produce mycotoxins in plant tissues. The use of fungicides in sustainable agricultural systems is limited; therefore, the application of biological agents with antifungal activity against Fusarium spp. is desirable. Lactic acid bacteria (LAB) are promising control agents that produce a wide spectrum of functional metabolites. Lactiplantibacillus plantarum and other lactobacilli are the most intensively studied genera of LAB in relation to antifungal activity against Fusarium spp. However, LAB strains belonging to the lactobacilli and lactococci genera have not yet been isolated and characterised from legumes. Therefore, we aimed to obtain wild strains of LAB from legumes, screen them for functional characteristics with respect to their antifungal activity, and compare their antifungal activity against isolates of Fusarium spp. from legumes. Consequently, 31 LAB isolates belonging to 10 species were obtained and identified from legumes. Their functional properties, including genetics and proteomics, short-chain organic acid production, and antifungal activity against five Fusarium spp., of Lactiplantibacillus plantarum, Lacticaseibacillus paracasei, and Lactiplantibacillus pentosus isolates, were studied. Cell-free supernatants of L. plantarum and L. pentosus showed significant suppression of mycelial growth and conidial germination. Full article

The effectiveness of lemon myrtle (LM) (Backhousia citriodora) essential oil (EO) was investigated to combat Penicillium digitatum by in vitro agar diffusion and vapour assay and in artificially infected oranges. The main constituent of LM EO was revealed as citral when analysed in gas chromatography–mass spectrometry. Pure citral was also included in the experiment for comparison. The in vitro fungal growth was significantly inhibited by LM EO at 1, 2, 3, 4 and 5 μL per disc while complete growth inhibition by both the pure citral and LM EO occurred at 4 and 5 μL per disc. Inoculated fruits treated by dipping in 1000 μL L⁻¹ LM EO solutions for 5, 10, 15, 30 and 120 s showed significantly lower fungal wounds compared to control. While longer dipping times led to some rind injuries, fruits with a 5 and 10 s dip were found free from any injury. The evaluation after dipping and storage confirmed that the fruits maintained the sensory attributes and were not compromised by the incorporation of the essential oil. The results of this study indicate that LM EO can be a promising alternative to synthetic fungicides for preserving the quality of citrus fruits during storage. Full article

Botrytis cinerea, causing grey mold, is a dangerous plant pathogen able to infect agricultural crops during the whole production cycle, including storage and transportation. A wide set of pathogenicity factors, high ecological plasticity, and universality of propagation and spreading of this fungus significantly complicate the control of this pathogen. A rapid increase in pathogen tolerance to fungicides dictates the necessity of developing antiresistant protection strategies, which include the use of biopreparations based on antagonistic microorganisms or their metabolites. The purpose of the study was to evaluate the antifungal activity of a dry biomass of P. chrysogenum VKM F-4876D (DMP), both individually and in combination with tebuconazole-, fludioxonil-, or difenoconazole-containing compounds recommended to control grey mold, in relation to B. cinerea isolated from grape samples. A water suspension of DMP was added to the PDA medium at a concentration of 1.0, 2.5, 5.0, 7.5, and 10.0 g/L. The pathogen growth inhibition was evaluated after 3, 7, and 14 days of cultivation; fungal cultures grown on DMP-free medium were used as a control. The resulting effective DMP concentration was 2.5 g/L. The effective concentrations of fungicides included in the study were determined to be 0.5 mg/L (tebuconazole), 0.1 g/L (difenoconazole), and 0.04 mg/L (fludioxonil). Combining DMP (2.5 g/L) with tebuconazole, difenoconazole, or fludioxonil (all taken at the effective concentrations) resulted in pathogen growth inhibition after 7 days of incubation by 86.5, 85.6, and 84.6%, respectively. Among all studied variants, the DMP (2.5 g/L) + difenoconazole (1.0 mg/L) combination provided the most efficient control of B. cinerea development under in vitro conditions: even after 14 days of incubation, the pathogen growth suppression remained at the level of 51.3%, whereas the DMP combination with tebuconazole or fludioxonil provided only 28.5 and 37.4%, respectively. The obtained results show good prospects for the efficient control of grey mold development, together with the reduction of pesticide loads on agrobiocoenoses and the prevention of the emergence of new resistant forms of plant pathogens. Full article