Search Results (2,747)

Microdochium species are harmful pathogens of winter cereals, causing snow mould and stem base diseases such as root rot. With changing climatic conditions, including prolonged wet autumns and mild winters, addressing pathogens that thrive at low positive temperatures has become increasingly important. Integrated strategies, including optimized sowing times, resistant cultivars, and the use of seed treatment fungicides have been suggested as effective approaches to mitigate Microdochium-induced damage. Field trials were conducted between 2021 and 2024 using five winter wheat cultivars treated with different seed treatment fungicides and sown at either optimal or delayed sowing times. Laboratory analyses identified Microdochium spp. as the dominant pathogens on the stem base across all trial years. Disease severity assessments indicated that seed treatment fungicides were generally effective against root rot, with products containing fludioxonil and SDHI group fungicides delivering the best performance. While disease pressure varied between optimal and late sowing experiments, late-sown winter wheat exhibited slightly reduced damage in most years. Additionally, some of the tested winter wheat cultivars demonstrated better performance against Microdochium spp. damage compared to others, highlighting the importance of selecting resistant cultivars. This study provides valuable insights into the control of Microdochium spp. under changing climatic conditions, particularly during the early growth stages of winter wheat. Full article

Managing foliar corn diseases like northern leaf blight (NLB) and gray leaf spot (GLS), which can occur rapidly and impact yield, requires proactive measures including early scouting and fungicides to mitigate these effects. Decision support tools, which use data from in-field monitors and predicted leaf wetness duration (LWD) intervals based on meteorological conditions, can help growers to anticipate and manage crop diseases effectively. Effective crop disease management programs integrate crop rotation, tillage practices, hybrid selection, and fungicides. However, growers often struggle with correctly timing fungicide applications, achieving only a 30–55% positive return on investment (ROI). This paper describes the development of a disease-warning and fungicide timing system, equally effective at predicting NLB and GLS with ~70% accuracy, that utilizes historical and forecast hourly weather data. This scalable recommendation system represents a valuable tool for proactive, practicable crop disease management, leveraging in-season weather data and advanced modeling techniques to guide fungicide applications, thereby improving profitability and reducing environmental impact. Extensive on-farm trials (>150) conducted between 2020 and 2023 have shown that the predicted fungicide timing out-yielded conventional grower timing by 5 bushels per acre (336 kg/ha) and the untreated check by 9 bushels per acre (605 kg/ha), providing a significantly improved ROI. Full article

Fungal infections are a significant global public health challenge because of their widespread occurrence, morbidity, and profound social and economic consequences. Antifungal resistance is also an increasing concern, posing a substantial risk to public health. There is a growing interest in searching for new antifungal drugs isolated from natural sources. This study aimed to evaluate the antifungal activity of novel mollusk fractions against fungal strains resistant to nystatin and amphotericin B. In addition, the role of oxidative stress in the mechanism of damage was determined. The mucus from the garden snail Cornu aspersum (MCa/1-20) and the hemolymph fraction from the marine snail Rapana venosa (HLRv/3-100) were obtained and characterized via 12% sodium dodecyl sulfate–polyacrylamide gel electrophoresis (SDS-PAGE) and mass spectrometric -analyses. The results demonstrate that the spores and biomass of both mollusk fractions have a significant fungicidal effect against Penicillium griseofulvum, and Aspergillus niger. Compared to the control group, the release of intracellular proteins and reducing sugars was significantly increased in the treated groups. The data showed increased levels of oxidative stress biomarkers (lipid peroxidation and oxidatively damaged proteins) and a downregulated antioxidant enzyme defense, corresponding to increased antifungal activity. To our knowledge, this is the first study evaluating oxidative stress as a factor in mollusk fractions’ antifungal activity. Full article

Tan spot (Pyrenophora tritici-repentis) and stripe rust (Puccinia striiformis f. sp. tritici) are major foliar diseases of wheat, causing significant yield losses globally. This study evaluated the efficacy of fungicide seed treatments in managing these diseases during early growth stages under greenhouse, growth chamber, and field conditions in the Northern Great Plains. Winter and spring wheat cultivars were treated with pyraclostrobin or combinations of thiamethoxam, difenoconazole, mefenoxam, fludioxonil, and sedaxane, among others. Greenhouse and growth chamber plants were inoculated with the respective pathogens, while field trials relied on natural inoculum. Fungicide treatments significantly reduced stripe rust severity (up to 36%) (p ≤ 0.05) and moderately reduced tan spot severity during early growth stages (15–20%). Treated plants demonstrated a 30–40% improvement in plant vigor, and a 25–50% increase in winter survival. Additionally, grain yield in treated plots increased by 25–50% (p ≤ 0.05), with test weight and protein content improving by 10% and 15%, respectively. These findings demonstrate the potential of fungicide seed treatments as an integrated pest (or pathogen) management (IPM) strategy to enhance early foliar disease control and wheat productivity. Full article

1, 2, 4-triazole derivatives, including tebuconazole, have been reported to show positive physiological effects in cereals apart from fungicidal activity and to increase plants’ tolerance against temperature stress. This study investigates the mechanisms of increasing frost resistance of etiolated winter wheat (Triticum aestivum L., “Irkutskaya” variety) seedlings by tebuconazole-based seed dresser “Bunker” (1.5 μL g⁻¹ of seeds) and tebuconazole (30 μg g⁻¹ of seeds). To identify ABA-dependent and ABA-independent pathways of frost resistance, we used fluridone (FLD, 5 mg L⁻¹), an inhibitor of endogenous abscisic acid (ABA) synthesis. FLD effectively inhibited the accumulation of carotenoids in the shoots and prevented the formation of carotenoids caused by the “Bunker” and tebuconazole. In non-hardened seedlings, FLD stimulated coleoptile and first leaf growth, but did not suppress the growth inhibitory effects of “Bunker” and tebuconazole. In shoots of hardened seedlings, FLD reduced the retarding effect of tebuconazole. Regardless of seedling age, temperature, and the protectant treatment, FLD had no effect on the sugar content in the shoots. FLD did not essentially influence frost resistance induced by “Bunker” and tebuconazole in cold-hardened seedlings. Fluridone increased H₂O₂ content and guaiacol peroxidase activity under control conditions (both with tebuconazole and without tebuconazole) and during cold hardening (in seedlings from seeds treated with tebuconazole). ABA levels in cold-hardened seedlings treated with FLD alone, tebuconazole alone, or a combination of the two were two to three times lower than in untreated hardened seedlings. Changes in indole-3-acetic and salicylic acids in response to FLD and tebuconazole treatment indicate complex interactions with signaling cellular systems. Our results suggest that tebuconazole activates ABA-independent pathways more strongly than ABA-dependent pathways in enhancing frost resistance. The potential mechanisms of tebuconazole action in plant cells are discussed. Full article

Agroecosystems provide habitats, food, and water for many pollinators and insects, but they are also heavily exposed to threats from the widespread use of pesticides and fertilizers. Managed honeybees and wild bees encounter pesticides in vineyards by collecting morning dew from vine leaves and accessing sugars from grapes, particularly during dry periods. This study assessed the toxicological effects of the commercial fungicide formulations Fantic FNCWG^® and Ramedit combi^®, both individually and in combination, on honeybees. Using a multi-biomarker approach, we evaluated neurotoxicity, metabolic disturbances, phase II detoxification processes, and immune system function. Our findings revealed that commercial fungicide mixtures with multiple active ingredients affect bees differently than single active compounds. Biomarker responses highlighted how these complex mixtures disrupt various enzymatic pathways; including immune function; altering critical enzyme kinetics involved in detoxification and potentially impairing essential bee functions. This study emphasizes the need for more comprehensive research into the sublethal effects of commercial pesticides, particularly those used in vineyards, which are understudied compared to pesticides used in orchards. Full article

Employing post-harvest treatments to maintain pomegranate fruit quality during storage is a prevalent practice within the food industry. IMAZALIL (IMZ), a fungicide, has demonstrated efficacy in reducing both the incidence of chilling injury symptoms and the presence of pathogenic fungi. This study aims to assess the impact of IMZ treatment on the technological quality (weight loss, color attributes (C* and h°), pH, titratable acidity, and total soluble solids), nutritional properties (total sugars content), and functional properties (total phenolic compounds (TPC) and total anthocyanin content (TAC)) in pomegranate fruits of the ‘Sefri Ouled Abdellah’ and ‘Kingdom’ cultivars. These fruits were collected in the Beni Mellal region and immediately stored at 4 °C for 120 days. Untreated pomegranates exhibited significant degradation in overall quality when stored in cold conditions. The fruits treated with IMZ are characterized by a major loss in weight (3.41% to 20.11%) compared to the control fruits (1.62% to 13.19%). This was accompanied by more pronounced color degradation in the IMZ-treated fruits relative to the control. This study substantiates the effectiveness of IMZ treatment in prolonging the post-harvest quality of pomegranates during cold storage, demonstrating superior efficacy in delaying losses in bioactive compounds by 39.44% and enhancing nutritional properties by 18.84%. This finding initiates the exploration of optimal IMZ concentrations and the best treatments to maintain the overall quality of pomegranate fruits. Full article

Postharvest decay of vegetables and fruits presents a significant threat confronting sustainable food production worldwide, and in the recent times, applying synthetic fungicides has become the most popular technique of managing postharvest losses. However, there are concerns and reported proofs of hazardous impacts on consumers’ health and the environment, traceable to the application of chemical treatments as preservatives on fresh produce. Physical methods, on the other hand, cause damage to fresh produce, exposing it to even more infections. Therefore, healthier and more environmentally friendly alternatives to existing methods for managing postharvest decays of fresh produce should be advocated. There is increasing consensus that utilization of biological control agents (BCAs), mainly fungi, represents a more sustainable and effective strategy for controlling postharvest losses compared to physical and chemical treatments. Secretion of antifungal compounds, parasitism, as well as competition for nutrients and space are the most common antagonistic mechanisms employed by these BCAs. This article provides an overview of (i) the methods currently used for management of postharvest diseases of fresh produce, highlighting their limitations, and (ii) the use of biocontrol agents as an alternative strategy for control of such diseases, with emphasis on fungal antagonists, their mode of action, and, more importantly, their advantages when compared to other methods commonly used. We therefore hypothesize that the use of fungal antagonists for prevention of postharvest loss of fresh produce is more effective compared to physical and chemical methods. Finally, particular attention is given to the gaps observed in establishing beneficial microbes as BCAs and factors that hamper their development, particularly in terms of shelf life, efficacy, commercialization, and legislation procedures. Full article

With the rising incidence of drug-resistant pathogens, focus should be placed on biologically active compounds derived from plant species used in herbal medicine, as these compounds may provide a new source of antifungal and antibacterial activities. The aim of this study was to evaluate the antifungal and antibacterial activity of ethanol and aqueous extracts from different parts of Rosa rugosa. In order to evaluate the antimicrobial activity of the extracts of R. rugosa rose hips, flowers, petals, leaves, stems, and roots, a laboratory microbiological test was performed using the well diffusion method in agar. A rotary evaporator was used for extract concentration and extractant removal. Antimicrobial activity was tested against one fungus, four Gram-positive, and four Gram-negative bacteria. The leaf extracts exhibited the strongest antimicrobial activity, followed by the extracts from the petals and rose hips, while weaker activity was observed in the root extracts. The extracts from the stems and rose hips showed the weakest effect. Ethanol extracts were more effective than water extracts. Aqueous and ethanolic extracts of R. rugosa parts demonstrated antifungal activity against Candida albicans, with ethanol extracts proving to be more effective. Among all the R. rugosa parts analyzed, the petals exhibited the strongest antifungal activity. Full article

Carbendazim (MBC), a commonly used fungicide from the benzimidazole group, was applied in this study as a probe molecule to understand the influence of sample preparation on the SERS (surface-enhanced Raman scattering) signal. We applied the external standard method (ESM), preparing fresh Ag colloid samples (reduced by hydroxylamine) for each concentration and measuring with and without potassium nitrate (KNO₃) as an aggregation-inducing salt. The impact of sample dilution before or after the addition of the salt to the Ag colloid was also explored. SERS signals were correlated with Ag colloid aggregation observed via transmission electron microscopy (TEM), UV-Vis extinction, dynamic light scattering (DLS), and zeta potential, examining diffusion-limited cluster aggregation (DLCA) and reaction-limited cluster aggregation (RLCA) mechanisms. The optimal results were achieved without KNO₃, with more compact aggregates at lower concentrations and more branched ones at higher concentrations. Dilution of the Ag colloid before salt addition enabled lower detection limits than without any dilution. No SERS signal was observed when the salt was added before dilution. These findings emphasize that a consistent relationship between aggregate morphology and the SERS signal cannot be generalized across analytes. Analyte-specific properties play a crucial role in determining optimal aggregation conditions for SERS analysis. Full article

In Chile and worldwide, walnut (Juglans regia L.) production faces significant losses due to crown and root rot caused by the phytopathogen Phytophthora cinnamomi. Currently, control methods have proven insufficient or unfavorable for the environment, increasing the need for sustainable alternatives. This research evaluates nanoemulsions based on extracts of medicinal plants endemic to Chile to control P. cinnamomi in walnut crops. The methodology included an in vitro test to determine the effective inhibitory concentrations of three nanoemulsions (N80, N90, and N100) on the mycelial growth of the phytopathogen, a test on walnut plants under controlled conditions, and two field tests using concentrations between 300 and 500 ppm. The in vitro results showed that the nanoemulsions could inhibit 90% of mycelial growth at 80 to 100 ppm concentrations. In the field, the N90 nanoemulsion at 500 ppm significantly reduced disease symptoms preventively and post-inoculation, compared with the control. This research is the first to study the use of nanoemulsions from native Chilean plants to control P. cinnamomi, showing potential to reduce the use of synthetic fungicides, contributing to safer and more ecological phytosanitary management. Full article

Santolina chamaecyparissus L. (cotton-lavender) is receiving increasing attention due to its potential for modern medicine and is considered both a functional food and nutraceutical. In this work, the phytochemical profile of its flower hydromethanolic extract was investigated by gas chromatography–mass spectrometry, and its applications as a biorational for crop protection were explored against Neocosmospora spp., both in vitro and in planta. The phytochemical profiling analysis identified several terpene groups. Among sesquiterpenoids, which constituted the major fraction (50.4%), compounds featuring cedrane skeleton (8-cedren-13-ol), aromadendrene skeleton (such as (−)-spathulenol, ledol, alloaromadendrene oxide, epiglobulol, and alloaromadendrene), hydroazulene skeleton (ledene oxide, isoledene, and 1,2,3,3a,8,8a-hexahydro-2,2,8-trimethyl-,(3aα,8β,8aα)-5,6-azulenedimethanol), or copaane skeleton (cis-α-copaene-8-ol) were predominant. Additional sesquiterpenoids included longiborneol and longifolene. The monoterpenoid fraction (1.51%) was represented by eucalyptol, (+)-4-carene, endoborneol, and 7-norbornenol. In vitro tests against N. falciformis and N. keratoplastica, two emerging soil phytopathogens, resulted in effective concentration EC₉₀ values of 984.4 and 728.6 μg·mL⁻¹, respectively. A higher dose (3000 μg·mL⁻¹) was nonetheless required to achieve full protection in the in planta tests conducted on zucchini (Cucurbita pepo L.) cv. ‘Diamant F1’ and tomato (Solanum lycopersicum L.) cv. ‘Optima F1’ plants inoculated with N. falciformis by root dipping. The reported data indicate an antimicrobial activity comparable to that of fosetyl-Al and higher than that of azoxystrobin conventional fungicides, thus making the flower extract a promising bioactive product for organic farming and expanding S. chamaecyparissus potential applications. Full article

A series of novel triazone derivatives containing aldehyde hydrazone or ketone hydrazone moieties were designed, synthesized and their biological activities were investigated against Aphis craccivora, Culex pipiens pallens, Helicoverpa armigera, Ostrinia nubilalis, Mythimna separata and 14 Kinds of fungi. Most of the aldehyde hydrazone exhibited excellent insecticidal activities against A. craccivora. In particular, the aphicidal activities of compounds 3t (35%) and 3w (30%) were equivalent to pymetrozine (30%) at 5 mg/kg. The aphicidal activities of derivatives 3p, 3u, 3y, 5g, 5i, 5l, 5q and 5u against C. pipiens pallens were higher than that of pymetrozine. Compound 3u (100%) exhibited good larvicidal activities against C. pipiens pallens at 0.25 mg/kg. Most derivatives exhibited broad-spectrum fungicidal activities against 14 kinds of plant fungi at 50 mg/kg. Thirty-nine compounds exhibited a more than 50% inhibition rate against Physalospora piricola. Compounds 3h, 3t and 3w were expected to be the leading structure for the development of new triazone insecticides agents. Full article

The plant pathogenic fungus Botrytis cinerea causes significant losses in agricultural production and it is rather difficult to control due to its broad host range and environmental persistence. The management of gray mold disease is still mainly based on the use of chemicals, which could have harmful effects not only due to impacts on the environment and human health, but also because they favor the development of fungicide-resistant strains. In this scenario, the strategy of RNA interference (RNAi) is being widely considered, and Spray-Induced Gene Silencing (SIGS) is gaining interest as a versatile, sustainable, effective, and environmentally friendly alternative to the use of chemicals in the protection of crops. The SIGS approach was evaluated to control B. cinerea infection on lettuce plants. In vitro-synthesized dsRNA molecules (BcBmp1-, BcBmp3-, and BcPls1-dsRNAs) were used naked, or complexed to small layered double hydroxide (sLDH) clay nanosheets. Therefore, treatments were applied by pressure spraying whole lettuce plants lately inoculated with B. cinerea. All sprayed dsRNAs proved effective in reducing disease symptoms with a notable reduction compared to controls. The effectiveness of SIGS in reducing disease caused by B. cinerea was high overall and increased significantly with the use of sLDH clay nanosheets. The sLDH clay nanosheet–dsRNA complexes showed better plant protection over time compared to the use of naked dsRNA and this was particularly evident at 27 days post-inoculation. RNAi-based biocontrol could be an excellent alternative to chemical fungicides, and several RNAi-based products are expected to be approved soon, although they will face several challenges before reaching the market. Full article

Difenoconazole (DIF), a demethylation inhibitor fungicide, was registered in 2016 for the control of postharvest diseases of pome fruits. In this study, 162 isolates from P. expansum (n = 31) and 13 other “non-expansum” Penicillium spp., i.e., P. solitum (n = 52), P. roqueforti (n = 32), P. commune (n = 15), P. paneum (n = 9), P. psychrosexuale (n = 8), P. crustosum (n = 5), P. carneum (n = 3), P. palitans (n = 2), along with one isolate each of P. citrinum, P. griseofulvum, P. raistrickii, P. ribium, and P. viridicatum, were collected from multiple packinghouses in the U.S. Pacific Northwest. In vitro sensitivity assays showed similar sensitivities of spores and mycelia across species with the mean EC₅₀ values ranging from 0.01 for P. psychrosexuale (n = 8) to 1.33 μg mL⁻¹ for P. palitans (n = 2), whereas the mean EC_50s were 0.03, 0.12, 0.19, and 0.51 μg mL⁻¹ for P. expansum (n = 31), P. paneum (n = 9), P. solitum (n = 52), and P. crustosum (n = 5), respectively. The recommended rate of DIF controlled P. expansum and P. roqueforti isolates but not all isolates of four other Penicillium spp. on Fuji apples after five months at 1.5 °C. The mixture of DIF + fludioxonil (FDL) (Academy^TM) controlled all the dual-sensitive isolates (DIF^SFDL^S) and DIF single-resistant (DIF^R) isolates among the six species tested but not the FDL^R and dual DIF^RFDL^R isolates. Notable polymorphism was detected in the CYP51 gene of the “non-expansum” species with four mutations located at four residues. Although the isolates analyzed in this study had not previously been exposed to DIF, the findings indicate variable sensitivity levels among the Penicillium spp. Full article