Search Results (495)

Wheat (Triticum aestivum L.) is a crucial global food crop. The intensive crop farming, monoculture cultivation, and impact of climate change affect the susceptibility of wheat cultivars to biotic stresses, mainly caused by soil fungal pathogens, especially those belonging to the genus Fusarium. This situation threatens yield and grain quality through root and crown rot. While conventional chemical fungicides face resistance issues and environmental concerns, biological alternatives like seed priming with natural metabolites are gaining attention. Polyamines, including putrescine, spermidine, and spermine, are attractive priming agents influencing plant development and abiotic stress responses. Spermine in particular shows potential for in vitro antifungal activity against Fusarium. Optimising spermine concentration for seed priming is crucial to maximising protection against Fusarium infection while ensuring robust plant growth. In this research, we explored the potential of the polyamine spermine as a seed treatment to enhance wheat resilience, aiming to identify a sustainable alternative to synthetic fungicides. Our findings revealed that a six-hour seed soak in spermine solutions ranging from 0.5 to 5 mM did not delay germination or seedling growth. In fact, the 5 mM concentration significantly stimulated root weight and length. In complementary in vitro assays, we evaluated the antifungal activity of spermine (0.5–5 mM) against three Fusarium species. The results demonstrated complete inhibition of Fusarium culmorum growth at 5 mM spermine. A less significant effect on Fusarium graminearum and little to no impact on Fusarium oxysporum were found. The performed analysis revealed that the spermine had a fungistatic effect against the pathogen, retarding the mycelium growth of F. culmorum inoculated on the seed surface. A pot experiment with Bulgarian soft wheat cv. Sadovo-1 was carried out to estimate the effect of seed priming with spermine against infection with isolates of pathogenic fungus F. culmorum on plant growth and disease severity. Our results demonstrated that spermine resulted in a reduced distribution of F. culmorum and improved plant performance, as evidenced by the higher fresh weight and height of plants pre-treated with spermine. This research describes the efficacy of spermine seed priming as a novel strategy for managing Fusarium root and crown rot in wheat. Full article

Phytoalexins are antimicrobial compounds of diverse chemical classes whose production is triggered in plants in response to pathogen infection. This study demonstrated that spraying with a celery flavonoid-rich extract (CFRE) or a spinach flavonoid-rich extract (SFRE) enhanced the production of phytoalexins in cucumber leaves artificially infected with powdery mildew incited by Podosphaera fusca. High-performance liquid chromatographic (HPLC) analysis revealed a noticeable increase in the content of phenolic acids, including caffeic acid, ellagic acid, ferulic acid, gallic acid, p-coumaric acid, and syringic acid, as well as the flavonoid rutin in both non-inoculated and inoculated leaves of cucumber seedlings treated with CFRE and SFRE, compared to healthy untreated leaves used as a control. Fluorescence microscopy revealed the accumulation of phenolic acid compounds in chloroplasts and at the periphery of epidermal cells. Overall, results suggest the reduced severity of P. fusca infection following the application of CFRE and SFRE in cucumber leaves could be due, at least in part, to the production of phytoalexins of polyphenolic nature. These findings provide insights into the mechanisms of systemic resistance induced by CFRE and SFRE. Moreover, they confirm these two natural flavonoid-rich products could be promising alternatives to synthetic chemical fungicides for the safe and ecofriendly control of cucumber powdery mildew. Full article

The conventional agricultural industry largely relies on pesticides to maintain healthy and viable crops. Application of fungicides, both pre- and post-harvest of crops, is the go-to method for avoiding and eliminating Botrytis cinerea, the fungal pathogen responsible for gray mold. However, conventional fungicides and their residues have purported negative environmental and health impacts. Natural products, such as essential oils, are viewed as a promising alternative to conventional fungicides. The current research is an in vitro study on the antifungal activity of a natural water-based fungicide (N.F.), which uses a blend of essential oils (ajowan, cassia, clove, eucalyptus, lemongrass, oregano) as the active ingredients against B. cinerea. Compared to conventional fungicides tested at the same concentration (50 μL/mL), those with active ingredients of myclobutanil or propiconazole; the N.F. demonstrated significant (F(3,16) = 54, p = <0.001) and complete fungal growth inhibition. While previous research has largely focused on the antifungal properties of single essential oils and/or isolated compounds from essential oils, this research focuses on the efficacy of using a blend of essential oils in a proprietary delivery system. This research is of importance to the fields of agronomy, ecology, and health sciences. Full article

Rubber tree (Hevea brasiliensis Muell. Arg.) is a major tropical cash crop in southern China, with Hainan and Yunnan provinces being the main planting areas. In July 2023, bark cracking and gumming were observed on the trunks of mature rubber trees in Haikou City, Hainan Province, leading to xylem rot, which severely impacted the healthy growth of the rubber trees. The present study was conducted to confirm the pathogenicity of the patho-gen associated with stem gummosis disease, characterize it using morphological and mo-lecular tools, and devise field management strategies. Pathogenicity testing showed that this strain induced symptoms similar to those of natural outdoor infestation. Based on morphological study and molecular analyses of internal transcribed spacer (ITS), transla-tion elongation factor 1 alpha (TEF1-α), and β-tubulin 2 (TUB2) sequences, the causal agent was identified as Lasiodiplodia theobromae. Field trials demonstrated that an inte-grated fungicide approach—combining trunk application of Bordeaux mixture with root irrigation using citric acid–copper 6.4% + chelated copper-ammonium 15% at both 0.1% and 0.2% concentration—effectively suppressed stem gummosis disease incidence in rub-ber trees. To the best of our knowledge, this is the first report of L. theobromae causing stem gummosis on rubber tree in China. The findings of this study can provide valuable infor-mation for the management strategies and understanding of this disease. Full article

The excessive use of synthetic pesticides has not only resulted in increased resistance among weeds and pests, leading to significant economic loss, but has also raised serious health and environmental concerns. Chalcones and their derivatives, known for their herbicidal, fungicidal, bactericidal, and antiviral properties, are emerging as promising bio-based candidates. These naturally occurring compounds have long been recognized for their beneficial health effects and wide-range applications. However, their limited concentration in plants, along with poor solubility and bioavailability, brings challenges for their development. The aim of this study was to examine the properties of a synthetic substance, pinocembrin dihydrochalcone (3-phenyl-1-(2,4,6-trihydroxyphenyl)-1-propanone), including its soil dissipation and adsorption. Additionally, we evaluated its antioxidant activity through the DPPH assay and FRAP experiments. This analysis aims to provide insights into its potential classification as a low risk pesticide. Full article

Biopesticides represent a safe and sustainable strategy for biological pest management, applicable to weed and fungal control. Biotechnological processing offers a promising approach to enhance the bioactivity of natural products for agricultural use. In this study, guishe juice, an agroindustrial residue derived from Agave lechuguilla, was bioprocessed via inoculation with Fusarium chlamydosporum, and its fungicidal and herbicidal potentials were evaluated. The fungal biotransformation led to the accumulation of phytochemicals, including flavonoids and polyphenols, significantly enhancing antioxidant activity to 76% and 96% as measured by DPPH and ABTS assays, respectively. The resulting bioprocessed guishe extract (BGE), particularly at 10% concentration (BGE-10), exhibited strong fungicidal activity, achieving 100% control of phytopathogenic fungi Fusarium spp. and Penicillium spp. Additionally, BGE-10 demonstrated a bioherbicidal effect, with a 77% weed control rate against Verbesina encelioides. These findings emphasize the potential of bioprocessed agave residues as dual-action bioagents, supporting the development of novel, eco-friendly agricultural solutions. Full article

The apple tree (Malus domestica), a member of the Rosaceae family, holds significant economic value but faces postharvest challenges, like blue mold caused by Penicillium expansum and gray mold caused by Botrytis cinerea. While synthetic fungicides are widely used, their limitations highlight the need for sustainable alternatives. This study explores the antifungal properties of extracts from Celtis australis, Olea europea var. sylvestris, Chamaerops humilis, and Asparagus albus against these pathogens. In vitro tests assessed mycelial growth inhibition, whereas in vivo trials consisted of measurement of weight loss, firmness, total soluble solids, titratable acidity, and maturity index. Moreover, the phytochemical traits of the extracts were determined using the Folin–Ciocalteu method and HPLC. The results revealed notable antifungal activity, particularly for Celtis australis extract at a concentration of 300 g L⁻¹, which led to significant mycelial growth inhibition (61% for P. expansum and 41% for B. cinerea), a reduction in diseases’ severity (39% and 50%), and a notable decrease in diseases’ incidence (43% and 48%), respectively. Phytochemical analysis reflected the presence of phenols and flavonoids in the tested extracts. Importantly, the natural treatments helped preserve the apples’ quality during storage. Molecular docking studies further revealed that major compounds in Celtis australis extract inhibit the 14α-demethylase enzyme, a key target in fungal sterols biosynthesis. Full article

Candida auris is an emerging multidrug-resistant fungal pathogen with a high affinity for skin colonization and significant potential for nosocomial transmission. This study aimed to develop and evaluate chitosan-based hydrogels loaded with nystatin and propolis as a topical antifungal strategy for skin decolonization of C. auris. The formulations were selected based on our previous results and optimized for cutaneous application. The internal structure of the hydrogels was investigated by polarized light microscopy, confirming the amorphous nature of propolis and the partial dispersion of nystatin. The antifungal activity was assessed against ten fluconazole-resistant C. auris strains. The CS-NYS-PRO1 formulation demonstrated the highest antifungal performance in the agar test, also reducing viable cell counts to undetectable levels within 6 h. Time–kill assays and SEM imaging confirmed the rapid fungicidal effect and revealed severe membrane disruption and cytoplasmic leakage. Molecular docking analyses indicated the strong binding of nystatin to both sterol 14α-demethylase (CYP51) and dihydrofolate reductase (DHFR) from C. auris, suggesting complementary membrane and intracellular mechanisms of action. These findings support the use of such hydrogels as a local, non-invasive, and biocompatible strategy for managing C. auris colonization, with promising implications for clinical use in infection control and the prevention of skin-mediated transmission in healthcare settings. Full article

Postharvest fungal infections, particularly by Botrytis cinerea, can cause up to 50% losses in fruits and vegetables, and the overuse of synthetic fungicides has led to resistant pathogen strains. We hypothesized that hexane (Hex) and methanolic (MeOH) extracts from peanut (P) and pecan nut (PN) shells possess antifungal properties effective against B. cinerea in strawberries. To test this, we conducted both in vitro and ex vivo assays using strawberries inoculated with B. cinerea, comparing two controls (T0: water; T1: commercial synthetic fungicide) with four treatments—Hex-P, MeOH-P, Hex-PN, and MeOH-PN—at 1000 and 2000 ppm (in vitro) and 4000 ppm (ex vivo). Total phenolic content (TPC) and antioxidant activity (AA) were also measured. MeOH-P and Hex-PN extracts at 2000 ppm significantly inhibited fungal mycelial growth in vitro. In ex vivo assays, MeOH-P reduced both disease incidence and severity comparably to the synthetic fungicide. MeOH-PN exhibited the highest TPC and AA. These findings support the potential use of MeOH-P extract as a natural alternative to synthetic fungicides for controlling B. cinerea in strawberries during postharvest storage. Full article

In this study, weekly grab samples extracted by solid-phase extraction (SPE) and stir bar sorptive extraction (SBSE) were compared for the analysis of 230 pesticides in surface waters. Samples were collected from three different locations around Melbourne, Australia. Analysis was performed using Gas Chromatography Quadrupole Time of Flight High Resolution Mass Spectrometry (GC-QToF-HRMS). The two extraction techniques were compared, among others, for their limits of detection, recovery, extraction, and quantification efficiency of pesticides, as well as spatial and temporal differences in detected compounds. The target compounds screened were pesticides belonging mainly to the categories of fungicides, insecticides, and herbicides. Although SBSE extracted more pesticides at two out of three sites, SPE extracted total concentrations up to four times higher than SBSE over all sampling sites. The log K_OW of detected pesticides only partially explained the differences in detection, with SBSE performing better in the absorption of hydrophobic compounds. In addition, matrix effects, in particular turbidity, appeared to hinder extraction of contaminants, especially for SBSE. Spatially, SBSE detected 10 pesticides more than SPE at two locations, while the opposite was true at the third location, where turbidity was higher. The types of pesticides detected varied slightly between techniques and locations. The study highlights the complementarity of SBSE and SPE for monitoring pesticides in natural environments. SBSE is an easy-to-use technique and allows for extraction of a higher number of pesticides at trace level, but it might not be the preferred option for highly turbid waters. SPE requires more tedious and complex sample processing but allows for a more accurate quantification of a broader range of pesticides. Full article

Honey bees and other pollinators are key to functioning natural and managed ecosystems. However, their health is threatened by many factors, including pesticides. Spraying fungicides during flowering of fruit trees is widespread even though it directly exposes pollinators to these fungicides. Here, we report a series of experiments designed to understand how the combination of propiconazole and carbendazim, marketed in China as Chunmanchun^®, affects honey bee health. With an acute oral toxicity of 23.8 μg a.i./bee over 24 h in the laboratory, we considered the acute mortality risk from normal Chunmanchun^® applications as relatively low. However, our comprehensive studies revealed other diverse effects: Chunmanchun^® reduced memory after classic conditioning by approximately 25% and altered the activity of protective enzymes and the composition of the honey bees’ gut microbiota. Specifically, the genus Lactobacillus was decreased by ~13%, and Bartonella and Snodgrassella were increased by ~10% and ~7.5%, respectively. The gut metabolome was also disrupted in diverse ways, possibly as a functional consequence of the microbiome changes. Thus, we demonstrated numerous sublethal effects of the combination of propiconazole and carbendazim, which adds to the growing evidence that agrochemicals and fungicides in particular can harm pollinator health in subtle ways that are not captured in simple mortality assays. Full article

The relationships between mycotoxins content in food commodities or feedstuffs and the foodborne diseases is well known. So far, the available data mainly include chemical methods of mycotoxins decontamination for agricultural commodities or raw materials, including mycotoxin binders. Therefore, the possible use of some natural and cost-effective supplements such as herbs, fungi, microorganisms, or plants with powerful and safe protection against mycotoxin-induced health ailments is the main subject of this review paper. Various antagonistic microorganisms or yeast with fungicidal properties, as well as some herbs or plants that suppress fungal development and the subsequent production of target mycotoxins and/or have protective effect against mycotoxins, are deeply studied in the literature, and practical suggestions are given in this regard. The protection by degradation, biotransformation, or binding of mycotoxins by using natural additives such as herbs or plants to feedstuffs or foods has also been thoroughly investigated and analyzed as a possible approach for ameliorating the target adverse effects of mycotoxins. Possible beneficial dietary changes have also been studied to potentially alleviate mycotoxin toxicity. Practical advice are provided for possible application of the same natural supplements in real-life practice for combating mycotoxin-induced health ailments. Natural feed supplements and bioactive compounds appeared to be safe emerging approaches to preventing health ailments caused by mycotoxins. However, the available data mainly address some in vitro studies, and more in vivo experiments are necessary for introducing such approaches in the real-life practice or industry. Generally, target herbal supplements, antioxidants, or polyenzyme complements could be used as powerful protectors in addition to natural mycotoxin binders. Bioactive agents and enzymatic degradation are reported to be very successful in regard to PAT and OTA, whereas antagonistic microorganisms/fungi/yeasts have a successful application against AFs and PAT-producing fungi. Full article

Alternaria Brown Spot (ABS) is one of the most critical diseases affecting susceptible mandarins worldwide, being a limiting factor in their cultivation. Although there are numerous reports on effective plant protection products against the disease, field control is failing. In the literature, some of the results are contradictory, depending on the study and experimental scale. Therefore, this paper aimed to analyze the empirical evidence to answer the following questions: (i) What plant protection products have been used to control ABS? (ii) What are the methodologies used to test the substances? (iii) Why is ABS field control failing? An extensive literature search was performed in five databases: WoS, Scopus, Google Scholar, PubMed, and SciELO. The search string used was “Alternaria alternata” AND “Citrus”. Records were classified into ten groups according to their main topic. Group 3 “microorganisms and natural substances” and group 4 “fungicides” were full-text reviewed for data extraction (98 reports). Details of the microorganisms, natural substances, and fungicides used against A. alternata, as well as summaries of the methodologies, are provided. During this research, we highlighted significant aspects that may be hindering the control of Alternaria alternata in citrus: long periods of fruit sensitivity, abundance and floatability of inoculum, rapid infections, the appearance of resistance to fungicides, moderate effectiveness inhibiting the germination of conidia, uncertainty about the times of application, and persistence of the products. Full article

The use of biological agents in food preservation is considered a sustainable, modern, and promising approach, in which the use of lactic acid bacteria (LAB) is a potential solution. Additionally, Vietnamese fermented cocoa beans, a naturally diverse microflora, have not yet been assessed for the selection of antifungal LAB. Therefore, this study focused on evaluating the antifungal activities against Aspergillus flavus UBOCC-A-10866 of 19 LAB strains isolated from Vietnamese fermented cocoa beans from the Dak Lak and Dong Nai provinces. The results showed that lactic strains were all capable of inhibiting fungi growth (from 18–99% of the fungal colony diameter after 7 days), of which five LAB strains (L13E48, L7E96, L22E96, L41E96, and L2DN120) were selected due to their great fungi inhibition activities (inhibition rate > 75%). The strain L41E96 (Lactiplantibacillus plantarum) was chosen as the best antifungal species with the minimum inhibitory concentration (MIC) and the minimum fungicidal concentration (MFC) of 0.36 mg/mL. Full article

The aim of this study was to examine the effects of foliar application of protein biostimulants in combination with extracts from field horsetail (E. arvense L.), common tansy (T. vulgare L.), or yarrow (A. millefolium L.) on winter wheat. Initially, the fungistatic activity and phytotoxicity of three extract concentrations (1%, 5%, 10%) were tested on reference plants. The average results indicated a decrease in root elongation stimulation with increasing concentrations of all extracts. Antimicrobial tests revealed that the 5% and 10% extracts exhibited the strongest activity, especially against S. griseus, whereas the 1% extracts showed no inhibitory effect. The 5% concentration was chosen as optimal due to its comparable efficacy to a reference fungicide. Subsequently, the impact of combining foliar application of extracts with protein biostimulants on wheat seedling and root length, chlorophyll fluorescence, photosynthetic pigments, and soil dehydrogenase activity was analyzed. Horsetail and yarrow extracts combined with biostimulants improved plant growth, depending on dose and combination. This was particularly evident for variants S5-B8, K5-B4, K5-B8, A-B8, for which seedling lengths were 23.6 cm (16.8%), 24.4 cm (20.8%), 23.9 cm (18.3%), and 23.6 cm (16.8%), respectively. The maximum increase in chlorophyll (a + b) content (38.30%, 35.81%, and 41.24%) occurred in plants treated with S5-B4, K5-B8, and A-B4, respectively, compared with non-treated plants. In contrast, tansy extracts reduced chlorophyll content (by up to 78%) and induced moderate stress. The research highlights the potential of natural fungicides to protect plants effectively while minimizing environmental and human health risks compared to conventional chemicals. Full article