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Three-dimensional (3D) printing is dramatically improving breast reconstruction by offering customized and precise interventions at various stages of the surgical process. In preoperative planning, 3D imaging techniques, such as computer-aided design, allow the creation of detailed breast models for surgical simulation, optimizing surgical outcomes and reducing complications. During surgery, 3D printing makes it possible to customize implants and precisely shape autologous tissue flaps with customized molds and scaffolds. This not only improves the aesthetic appearance, but also conforms to the patient's natural anatomy. In addition, 3D printed scaffolds facilitate tissue engineering, potentially favoring the development and integration of autologous adipose tissue, thus avoiding implant-related complications. Postoperatively, 3D imaging allows an accurate assessment of breast volume and symmetry, which is crucial in assessing the success of reconstruction. The technology is also a key educational tool, enhancing surgeon training through realistic anatomical models and surgical simulations. As the field evolves, the integration of 3D printing with emerging technologies such as biodegradable materials and advanced imaging promises to further refine breast reconstruction techniques and outcomes. This study aims to explore the various applications of 3D printing in breast reconstruction, addressing current challenges and future opportunities.

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Fludioxonil is a highly effective phenylpyrrole fungicide for controlling Botrytis cinerea. Although the field efficacy of fludioxonil remains high, Botrytis cinerea isolates with reduced sensitivity have been reported globally. The molecular target of fludioxonil still remains unknown; however, a mechanism of reduced sensitivity to fludioxonil underlies the overexpression of the ATP binding cassette (ABC) transporter AtrB in a dependent pathway of the Mrr1 transcription factor. Fludioxonil is a key player in controlling B. cinerea infection in table grapes in Chile. However, some isolates with a reduced sensitivity to fludioxonil were detected. This study observed endogenous atrB overexpression in Chilean isolates with reduced sensitivity to fludioxonil (n = 22) compared to the sensitive isolates (n = 10). All isolates increased the expression of atrB in a growth medium supplemented with fludioxonil (0.05 µg/mL). However, sensitive isolates showed lower atrB expression than those with reduced fludioxonil sensitivity. Remarkably, a mutant version of the transcription factor Mrr1 carrying 21 amino acid modifications was identified in all isolates with reduced sensitivity to fludioxonil. These changes alter the protein's transcription factor domain and the C-terminal portion of the protein but not the Zn (2)-C6 fungal-type DNA-binding domain. These results suggest a direct relationship between the conserved and divergent mutant version of mrr1 and sensitivity to fludioxonil. This study provides a new target for developing molecular diagnostic strategies to monitor B. cinerea's sensitivity to fludioxonil in the field.

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Background: Outdoor aeroallergens, such as pollens and molds, are known triggers of asthma exacerbation; however, few studies have examined children's aeroallergen response based on sensitization. Objective: Our aim was to compare the relative impact of aeroallergen levels on asthma exacerbation between pediatric patients with asthma who tested positive or negative for sensitization to particular allergens. Methods: A case-crossover design study was conducted to examine associations between outdoor aeroallergen levels and asthma exacerbation events among children living in Philadelphia, Pennsylvania, who were treated within a large pediatric care network. Sensitization to common allergens was characterized in a subset of patients with asthma exacerbation who had undergone skin prick testing (5.5%). Odds ratios (ORs) and 95% CIs were estimated in all patients with asthma exacerbation and in those sensitized or not sensitized to aeroallergens. Results: Children who were sensitized to a particular allergen had higher odds of asthma exacerbation with exposure to the allergen (ie, early-season tree pollen, oak tree pollen, early-season weed pollen, and late-season molds) than did all patients with asthma or nonsensitized patients. For example, the association between early-season tree pollen and asthma exacerbation among sensitized children (>90th percentile vs ≤25th, OR = 2.28 [95% CI = 1.23-4.22]) was considerably stronger than that estimated among all patients (OR = 1.34 [95% CI = 1.19-1.50]), and it was also substantially different from the lack of association seen among nonsensitized children (OR = 0.89 [95% CI = 0.51-1.55] [P value for heterogeneity = .03]). Conclusion: More prevalent allergy testing may be useful for prevention of asthma exacerbation by informing interventions targeted to sensitized children and tailored for particular aeroallergens.

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OBJECTIVE: To identify and registry the most important fungal spores trapped in our aerobiology station, as well as to report the prevalence of skin sensitization to these allergens. METHODS: The pollen counts were made according to standardized technique with a Burkard seven days spore trap, following the American Academy of Allergy, Asthma and Immunology (AAAAI) through National Allergy Bureau (NAB) recommendations. The trap was installed on the roof of Clinica SANNA, El GOLF, San Isidro, which is 20 m high, 12°5'54"S 77°3'6"W in the west-south of the Lima urban area. The sampling period was performed from September 2020 to October 2021. Skin prick tests were carried out according to the recommendations of the Spanish Society of Allergology and Clinical Immunology (SEAIC) in 200 patients (18 to 60 years old) with symptoms of rhinoconjunctivitis and/or asthma, who were evaluated in the Allergology Service of Clinica SANNA el Golf. Allergenic extracts were applied, dust mites (Dermatophagoides pteronyssinus, Dermatophagoides farinae, Blomia tropicalis), cat and dog danders, cockroach (Periplaneta americana), grass 6 mix, weed mix, molds (Cladosporium herbarum, Alternaria alternata, Aspergillus fumigatus, Penicillium notatum, Nigrospora spp.), INMUNOTEK-Spain provided the extracts. We also tested other fungal allergens such as Fusarium spp, Stemphylium spp, Curvularia spp, a mixture of Helmintosporum/Dreschlera spp. from the DIATER-Argentina laboratory. RESULTS: We identified spores of Alternaria alternata, Cladosporium spp., Nigrospora spp., Stemphylium spp., Fusarium spp., Curvularia spp., Dreschlera/Helmintosporum spp. The patients showed sensitization to Cladosporium herbarum (14%), Fusarium spp. (13,5%), Nigrospora spp. (8%), Alternaria Alternata (7%), Stemphylium (6%), Dreschlera/Helmintosporium spp. (5,5%), Curvularia spp. (3%), Aspergillus fumigatus (2,5%). CONCLUSIONS: The inhabitants of the south-western area of the urban city of Lima are exposed to different fungal spores with allergenic potential, with a higher concentration being identified during the summer/autumn months. Cutaneous sensitization is demonstrated in variable percentages to the fungal spores identified in this aerobiological sampling. The results of this study should be expanded and compared with data in the forthcoming years, identify seasonal and annual fluctuations and extend the traps to other locations in Lima.

OBJETIVO: Identificar y registrar las esporas de hongos más importantes captadas en nuestra estación de aerobiología, además reportar la prevalencia de sensibilización cutánea a estos alérgenos. MÉTODOS: La identificación y los conteos de esporas de hongos se realizaron según la técnica estandarizada con un equipo colector Burkard Spore Trap For Seven Days, siguiendo las recomendaciones de la National Allergy Bureau (NAB), de la American Academy Allergy Asthma and Immunology (AAAAI). El equipo se instaló a 20 m de altura desde el nivel del suelo, en la azotea de la Clínica SANNA El Golf, distrito de San Isidro, (12°5'54"S 77°3'6"O), en la zona sur-oeste del área urbana de Lima. El periodo de captación se llevó a cabo entre septiembre de 2020 y octubre de 2021. Se realizaron estudios de pruebas cutáneas (skin prick-test), según recomendaciones de la Sociedad Española de Alergología e Inmunología Clínica (SEAIC), en 200 pacientes (entre 18 y 60 años), con sintomatología de rinoconjuntivitis y/o asma. Fueron evaluados en el servicio de Alergología de la Clínica SANNA El Golf. Se aplicaron extractos alergénicos de ácaros del polvo (Dermatophagoides pteronyssinus, Dermatophagoides farinae, Blomia tropicalis), epitelios de gato y perro, Periplaneta americana, mezclas de seis gramíneas, mezclas de malezas, hongos ambientales (Cladosporium herbarum, Alternaria alternata, Aspergillus fumigatus, Penicillium notatum, Nigrospora spp.), extractos del laboratorio INMUNOTEK-España. Además, testeamos otros alérgenos fúngicos de Fusarium spp, Stemphylium spp, Curvularia spp, una mezcla de Helmintosporum/Dreschlera spp. del laboratorio DIATER-Argentina. RESULTADOS: Identificamos esporas de Alternaria alternata, Cladosporium spp., Nigrospora spp., Stemphylium spp., Fusarium spp., Curvularia spp., Dreschlera/Helmintosporum spp. Los pacientes mostraron sensibilización a Cladosporium herbarum (14%), Fusarium spp. (13,5%), Nigrospora spp. (8%), Alternaria Alternata (7%), Stemphylium (6%), Dreschlera/Helmintosporium spp. (5,5%), Curvularia spp. (3%) y Aspergillus fumigatus (2,5%). CONCLUSIONES: Los habitantes de la zona sur-oeste de la ciudad urbana de Lima están expuestos a distintas esporas de hongos con potencial alergénico, identificándose mayor concentración durante los meses de verano y otoño. Se demuestra sensibilización cutánea en porcentajes variables a las esporas fúngicas identificadas en este muestreo aerobiológico. Los resultados de este estudio deberían ampliarse y ser comparados con data en los años siguientes, identificar fluctuaciones estacionales y anuales y extender los captadores a otras locaciones en Lima.

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Bell pepper presents rapid weight loss and is highly susceptible to gray mold caused by the fungus Botrytis cinerea. The most employed method to control this disease is the application of synthetic fungicides such as thiabendazole (TBZ); however, its continued use causes resistance in fungi as well as environmental problems. For these reasons, natural alternatives arise as a more striking option. Currently, bell pepper fruits are coated with carnauba wax (CW) to prevent weight loss and improve appearance. Moreover, CW can be used as a carrier to incorporate essential oils, and previous studies have shown that thyme essential oil (TEO) is highly effective against B. cinerea. Therefore, this study aimed to evaluate the effect of CW combined with TEO on the development of gray mold and maintenance of microestructural and postharvest quality in bell pepper stored at 13°C. The minimal inhibitory concentration of TEO was 0.5%. TEO and TBZ provoked the leakage of intracellular components. TEO and CW + TEO treatments were equally effective to inhibit the development of gray mold. On the quality parameters, firmness and weight loss were ameliorated with CW and CW + TEO treatments; whereas lightness increased in these treatments. The structural analysis showed that CW + TEO treatment maintained the cell structure reducing the apparition of deformities. The results suggest that CW + TEO treatment could be used as a natural and effective antifungal retarding the appearance of gray mold and maintaining the postharvest quality of bell pepper. PRACTICAL APPLICATION: CW and TEO are classified as generally recognized as safe (GRAS) by the US Food and Drug Administration (FDA). This combination can be employed on the bell pepper packaging system to extend shelf life and oppose gray mold developments. Bell pepper fruits are normally coated with lipid-base coatings such as CW before commercialization; therefore, TEO addition would represent a small investment without any changes on the packaging system infrastructure.

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In August 2018, symptoms of apical and basal rot resembling those caused by Sclerotinia sclerotiorum infection were observed in a commercial Brussels sprouts field in North Patagonia, Argentina. The incidence of apical and basal rot was 23.30% and 2.30%, respectively. Carpogenic germination of sclerotia was detected in shaded, highly humid soil areas. To our knowledge, this is the first report of carpogenic germination of sclerotia from S. sclerotiorum in North Patagonia.

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The dragon fruit is native of Mexico, and Puebla is the third-largest producing state (SIAP 2023). In June 2023, field sampling was conducted in El Paraíso, Atlixco (18° 49' 5.275" N, 98° 26' 52.353" W), Puebla, Mexico. The mean temperature and relative humidity were 20 °C and 75% for seven consecutive days. Dragon fruits cv. 'Delight' close to harvest with gray mold symptoms were found in a commercial area of 2 ha, with an incidence of 35 to 40% and an estimated severity of 75% on infected fruit. The symptoms included necrosis at the apex, which later spread throughout the fruit, along with a soft, black rot covered in abundant mycelium and sporulation. The fungus was isolated from 40 symptomatic fruits by disinfesting pieces of necrotic tissue with 3% NaClO for one minute, rinsing with sterile distilled water (SDW), plating on Petri dishes with potato dextrose agar, and incubating at 25 °C in the dark. One isolate was obtained from each diseased fruit by the hyphal-tip method. The colonies were initially white with a growth rate of 1.15-1.32 cm per day and turned gray after 10 days; the mycelium was dense and aerial. Spherical and irregular sclerotia were formed, measuring 0.9-1.4 × 0.6-1.1 mm (n = 100). Each Petri dish produced 56-278 sclerotia (n = 40) after 11 days; these were initially white and gradually turned dark brown. Brown to olive conidiophores were straight, septate, and branched, measuring 1075-1520 × 10-21 µm, with elliptical hyaline to light brown conidia of 6.6-11.5 × 5-8.1 µm (n=100). The isolates were tentatively identified as Botrytis cinerea based on morphological characteristics (Ellis 1971). Two representative isolates were chosen for molecular identification and genomic DNA was extracted by the CTAB protocol. The ITS region and the heat shock protein (HSP60), RNA polymerase binding II (RPB2) and glyceraldehyde 3-phosphate dehydrogenase (G3PDH) genes were sequenced (White et al. 1990; Staats et al. 2005). The sequences of a representative isolate (BcPh5) were deposited in GenBank (ITS-OR582337; HSP60-OR636622; RPB2-OR636623; and G3PDH-OR636621). BLAST analysis of the partial sequences of ITS (479 bp), HSP60 (1006 bp), RPB2 (1126 bp), and G3PDH (907 bp) showed 100% similarity to B. cinerea isolates (GenBank: KM840848, MH796663, MK919495, MF480679). Phylogenetic analysis confirmed that BcPh5 clustered with B. cinerea strains. Pathogenicity was confirmed by inoculating the non-wounded surface of 20 detached dragon fruits cv. 'Delight' using the BcPh5 isolate by depositing 20 µl of a 105 conidia/ml suspension with a sterile syringe. The fruits were placed on the rim of a plastic container and inserted in a moisture box with 2 cm of water at the bottom. The box was covered with a plastic sheet to maintain humidity. Control fruits were inoculated with SDW. The inoculated fruits became covered with abundant white to gray mycelium, and soft rot developed within eight days, while no symptoms were observed on the controls. The fungus was re-isolated from the inoculated fruits as described above, fulfilling Koch's postulates. The pathogenicity tests were repeated three times. Gray mold caused by B. cinerea was also recently reported in Mexico on pomegranate (Hernández et al. 2023) and rose apple (Isodoro et al. 2023). As far as we know, this is the first report of B. cinerea causing gray mold on dragon fruit in Mexico. This research is essential for designing integrated management strategies against gray mold on dragon fruits.

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The microbiota refers to all the microorganisms living in and on the human body; its fungal component is known as the mycobiota. The molecular component (mycobiome) has been linked to certain pulmonary diseases. Morphological fungal examination is still common practice and makes it possible to isolate fungi on direct examination or after sample culture. This study aimed to identify fungi via the genus colonising the respiratory tract in our environment and to evaluate the relationship between identified fungi and underlying diseases. We performed a retrospective study of patients who underwent bronchofiberoscopy and mycological analysis of fluid collected by broncho-alveolar lavage at our centre over a period of 5 years. During the study period, 1588 samples from 1547 patients were analysed (50.7% male, mean age 63.7 ± 14.8 years). Among the 1588 samples, 213 (13.4%) were positive on direct examination, and 1282 (80.8%) were positive after culture. The average number of species detected per sample was 1.4 ± 1.1. For patients with positive fungus, the median was two (ranging from one to seven). At least three fungal species were isolated in 14.4% of samples (17.9% of positive cultures), and at least two were isolated in 41.2% of samples (51.1% of positive cultures). Sterile mycelium was observed in 671 samples (42.28%), while Candida was identified in 607 samples (38.25%), and Geotrichum was identified in 271 samples (17.08%). Moulds were more frequently associated with bronchiectasis, while yeasts were associated with infectious pneumonia. Both moulds and yeasts were less frequent in diffuse interstitial lung disease, and yeast was less frequently present in chronic cough. Although overall, sterile mycelium and Candida were most frequently observed regardless of the underlying disease, there was nonetheless significant variability in the fungal genera between diseases. Fungal spores are highly prevalent in respiratory samples in Martinique. The species present in the samples varied according to the underlying respiratory disease.

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Castor (Ricinus communis L.) is an important industrial crop with a wide range of industrial and pharmaceutical applications. Brazil is among the largest castor-producing countries. Between 2004 and 2010, castor cultivation was stimulated with an emphasis towards biodiesel production. However, this was not enough to leverage the production of castor in Brazil, mainly due to the lack of structured trade and the competition with other cheaper raw materials for the production of biodiesel. Despite this failure, the species presents itself as an excellent alternative for crop rotation in the second crop among soybean, corn, beans, and cotton cultivation areas as the oil is highly valuable for other products. Moreover, it has drawn the attention of producers and researchers in Brazil for this potential rotation as it is considered a plant tolerant of water-deficiency and is highly susceptible to gray mold, a disease favored by high humidity in the final stages of the crop. For instance, its cultivation in the second crop in Cerrado regions, where rains occur in the early stages of the crop and cease when the plants reach the final stage of production, has been successful and shows great promise. The current study aimed to evaluate the suitability of environments throughout Brazil to grow castor, incorporating variables associated with the incidence of gray mold and confirm these findings based on existing castor trial data obtained from the literature. The site suitability analysis determined that 74.99 million hectares - 8.8% of Brazilian territory - are highly suitable for castor production during second harvest, mostly located in the Northeastern and Midwestern regions. These results are surprising since Brazil currently has around 7.8% (∼66.81 million hectares) of its territory occupied with agriculture (grains, fruits, vegetables, and perennial crops). The findings of this study provide a method to perform site suitability for crops using data associated with agronomic and disease characteristics, as is the case with gray mold that often results in significant losses in castor production. Also, this analysis provides evidence for the great potential of Brazil to increase castor production and meet the world demand for its oil through utilization of second-crop cultivation.

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The literature is full of studies reporting environmental and health issues related to using traditional pesticides in food production and storage. Fortunately, alternatives have arisen in the last few decades, showing that organic agriculture is possible and economically feasible. And in this scenario, fungi may be helpful. In the natural environment, when associated with plants, these microorganisms offer plant-growth-promoting molecules, facilitate plant nutrient uptake, and antagonize phytopathogens. It is true that fungi can also be phytopathogenic, but even they can benefit agriculture in some way-since pathogenicity is species-specific, these fungi are shown to be useful against weeds (as bioherbicides). Finally, plant-associated yeasts and molds are natural biofactories, and the metabolites they produce while dwelling in leaves, flowers, roots, or the rhizosphere have the potential to be employed in different industrial activities. By addressing all these subjects, this manuscript comprehensively reviews the biotechnological uses of plant-associated fungi and, in addition, aims to sensitize academics, researchers, and investors to new alternatives for healthier and more environmentally friendly production processes.

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Onychomycosis is the most prevalent nail ailment in adults, accounting for 50% of all nail infections. Dermatophyte fungi are the primary cause, but non-dermatophyte molds (NDM) and yeasts can also cause onychomycosis. It remains important to precisely determine the fungal cause of onychomycosis since the response to current treatments may vary between fungal classes. Real-time polymerase chain reaction (qPCR) has become a widespread tool for detecting fungal organisms for diagnosis due to its sensitivity and ability to detect down to the species level. This retrospective study aims to evaluate the qPCR Onycho+ test for dermatophyte detection using remnants of toenails from a cohort of patients from Puerto Rico.  Two hundred forty-two toenail samples submitted for histological examination via Periodic acid Schiff (PAS) staining for suspected onychomycosis were analyzed by the Onycho+ test and Sanger sequencing of the internal transcribed spacer (ITS-2). Compared to the gold standard Sanger sequencing method, the Onycho+ test reported an agreement of 91.39%, a sensitivity of 100% and a specificity of 84.5% in detecting dermatophytes, superior to the histology method which had a 69.53% agreement, 85.1% sensitivity and 57.1% specificity. The distribution of fungal organisms detected in this cohort shows a dermatophyte majority but a higher-than-expected proportion of NDMs. Nails negative for the Onycho+ test and positive for histology were mostly NDMs. This study demonstrates that the clinical performance of the Onycho+ test is superior to histology in detecting dermatophytes and that a combination of Onycho+ and histology can result in a higher clinical accuracy.

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Infection by Aspergillus covers a broad clinical spectrum, including invasive pulmonary aspergillosis (IPA) and its disseminated extrapulmonary form, invasive aspergillosis (IA). It typically occurs in severely immunocompromised hosts, but it sometimes affects the immunocompetent population, especially patients with acute diseases being treated at the intensive care unit (ICU) and less often those with chronic conditions. In this article, we report the case of a 50-year-old male, with diabetes mellitus (DM) as the only risk factor, treated for IPA and IA with cardiac and central nervous system (CNS) involvement at a high complexity institution in Cali-Colombia. Clinical presentation and radiological findings are unspecific and require a high level of suspicion. To confirm the case, histological or cytological of the fungus is required; histopathological examination of lung tissue is the gold standard, but it is difficult to perform due to respiratory compromise and high risk of bleeding, so bronchoscopy and bronchoalveolar lavage (BAL) plays an essential role in the diagnostic process. A diagnostic algorithm that includes risk assessment, symptoms, imaging findings, and isolation in cultures is essential to allow the diagnosis and initiation of treatment promptly, which includes a combination of surgery and antifungal medications for long periods, even life-long treatment.

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One hundred twenty-five yeast strains isolated from table grapes and apples were evaluated for the control Botrytis cinerea of in vitro and in vivo. Ten strains were selected for their ability to inhibit mycelial growth of B. cinerea in vitro. In the in vivo assays, these yeasts were tested at 20 °C on 'Thompson Seedless' berries for 7 days; only three were selected (m11, me99 and ca80) because they significantly reduced the incidence of gray mold. These three yeast strains were then evaluated at different concentrations (1 × 107, 1 × 108 and 1 × 109 cells mL-1) on 'Thompson Seedless' grape berries at 20 °C. The strains m11, me99 and ca80 reduced the incidence of B. cinerea to 11.9, 26.1 and 32.1%, respectively, when the berries were submerged in a yeast suspension at a concentration of 1 × 109 cells mL-1 24 h before inoculation with B. cinerea. The most favorable pH for antifungal activity was 4.6 in the three isolates. The three yeast strains secreted the hydrolytic enzymes chitinase and ß-1-glucanase, and two strains (me99 and ca80) produced siderophores. The three yeast strains exhibited low oxidative stress tolerance and only strain m11 had the ability to produce biofilms. The strains were identified using 5.8S-ITS rDNA PCR-RFLP and correspond to the Meyerozyma guilliermondii (m11) and Aureobasidium pullulans (me99 and ca80) species.

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Lytic enzymes secreted by Kluyveromyces marxianus can lyse Saccharomyces cerevisiae cells. Their ability to hydrolyze yeast cell walls can be used in biotechnological applications, such as the production of glucans and protoplasts, as well as a biological control agent against plant pathogenic fungi. Herein, 27 proteins secreted by K. marxianus were identified by mass spectrometry analyses. Importantly, 14 out of the 27 proteins were classified as hydrolases. Indeed, the enzyme extract secreted by K. marxianus caused damage to S. cerevisiae cells and reduced yeast cell viability. Moreover, K marxianus inhibited spore germination and mycelial growth of the phytopathogenic fungus Botrytis cinerea in simultaneous cocultivation assays. We suggest that this inhibition may be partially related to the yeast's ability to secrete lytic enzymes. Consistent with the in vitro antagonistic tests, K. marxianus was able to protect strawberry fruits inoculated with B. cinerea. Therefore, these findings suggest that K. marxianus possesses potential as a biocontrol agent against strawberry gray mold during the postharvest stage and may also have potential against other phytopathogenic fungi by means of its lytic enzymatic arsenal.

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Botrytis cinerea, Rhizoctonia solani and Hemileia vastatrix are three species of phytopathogenic fungi behind major crop losses worldwide. These have been selected as target models for testing the fungicide potential of a series of bis(ylidene) cyclohexanones. Although some compounds of this chemical class are known to have inhibitory activity against human pathogens, they have never been explored for the control of phytopathogens until now. In the present work, bis(ylidene) cyclohexanones were synthesized through simple, fast and low-cost base- or acid-catalyzed aldol condensation reaction and tested in vitro against B. cinerea, R. solani and H. vastatrix. bis(pyridylmethylene) cyclohexanones showed the highest activity against the target fungi. When tested at 200 nmol per mycelial plug against R. solani., these compounds completely inhibited the mycelial growth, and the most active bis(pyridylmethylene) cyclohexanone compound had an IC50 of 155.5 nmol plug-1. Additionally, bis(pyridylmethylene) cyclohexanones completely inhibited urediniospore germination of H. vastatrix, at 125 µmol L-1. The most active bis(pyridylmethylene) cyclohexanone had an IC50 value of 4.8 µmol L-1, which was estimated as approximately 2.6 times lower than that found for the copper oxychloride-based fungicide, used as control. Additionally, these substances had a low cytotoxicity against the mammalian Vero cell line. Finally, in silico calculations indicated that these compounds present physicochemical parameters regarded as suitable for agrochemicals. Bis(ylidene) cyclohexanones may constitute promising candidates for the development of novel antifungal agents for the control of relevant fungal diseases in agriculture.

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This study evaluated the effects of potassium and sodium carbonate and bicarbonate, Bacillus subtilis (Cohn, 1872) QST-713, Bacillus pumilus (Meyer & Gottheil, 1901) QST-2808, and crude and roasted coffee oils on the inhibition of mycelial growth and conidial germination in Botrytis cinerea Pers.: Fr and the colonization of begonia (Begonia elatior Hort. ex Steud) leaf discs by B. cinerea inoculated before, simultaneously and after with these alternative products. The assays were carried out using the Baladin begonia cultivar. The inhibition of B. cinerea mycelial growth and conidial germination was proportional to increases in the concentration of all the products. The inhibition of conidial germination was directly proportional to the concentrations of B. pumilus QST-2808 and B. subtilis QST-713. Coffee oils were less efficient in inhibiting germination than the other products. The crude and roasted coffee oils, potassium and sodium carbonates and bicarbonates, and B. pumilus and B. subtilis sprayed 24 h before, simultaneously, or 24 h after pathogen inoculation inhibited the colonization of begonia leaf discs by B. cinerea. The positive results for the suppression of B. cinerea by the alternative products tested herein merit scrutiny. There is a pressing need to evaluate these products in the management of gray mold, as the severity of this disease is usually high under favorable conditions in greenhouses.

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The association of both cell-surface PRRs (Pattern Recognition Receptors) and intracellular receptor NLRs (Nucleotide-Binding Leucine-Rich Repeat) in engineered plants have the potential to activate strong defenses against a broad range of pathogens. Here, we describe the identification, characterization, and in planta functional analysis of a novel truncated NLR (TNx) gene from the wild species Arachis stenosperma (AsTIR19), with a protein structure lacking the C-terminal LRR (Leucine Rich Repeat) domain involved in pathogen perception. Overexpression of AsTIR19 in tobacco plants led to a significant reduction in infection caused by Sclerotinia sclerotiorum, with a further reduction in pyramid lines containing an expansin-like B gene (AdEXLB8) potentially involved in defense priming. Transcription analysis of tobacco transgenic lines revealed induction of hormone defense pathways (SA; JA-ET) and PRs (Pathogenesis-Related proteins) production. The strong upregulation of the respiratory burst oxidase homolog D (RbohD) gene in the pyramid lines suggests its central role in mediating immune responses in plants co-expressing the two transgenes, with reactive oxygen species (ROS) production enhanced by AdEXLB8 cues leading to stronger defense response. Here, we demonstrate that the association of potential priming elicitors and truncated NLRs can produce a synergistic effect on fungal resistance, constituting a promising strategy for improved, non-specific resistance to plant pathogens.

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Microbial crop protection products based on Trichoderma have the ability to display multifunctional roles in plant protection, such as pathogen parasitism, enhance nutrient availability and stimulate plant growth, and these traits can be used to enhance the overall agronomic performance of a variety of crops. In the current study, we explored the multifunctional potential of two indigenous Brazilian strains of Trichoderma (T. asperelloides CMAA 1584 and T. lentiforme CMAA 1585) for their capability of controlling Sclerotinia sclerotiorum, a key plant pathogen of cotton, and for their ability of growth promotion in cotton plants (Gossypium hirsutum). Both strains were able to solubilize mineral phosphorus (CaHPO4), to release volatile organic compounds that impaired the mycelial growth of S. sclerotiorum, and to promote the growth of cotton plants under greenhouse conditions. In dual culture, Trichoderma strains reduced the growth rate and the number of sclerotia formed by S. sclerotiorum. By treating sclerotia with conidial suspensions of these Trichoderma strains, a strong inhibition of the myceliogenic germination was observed, as a result of the marked mycoparasitic activity exerted on the sclerotia. The parasitism over S. sclerotiorum was more effective with T. asperelloides CMAA 1584, whilst the biostimulant effects on cotton growth were more pronounced with T. lentiforme CMAA 1585, which also showed a higher capacity of phosphate solubilization. Thus, T. asperelloides CMAA 1584 displays higher efficiency in controlling S. sclerotiorum, while T. lentiforme CMAA 1585 is more suitable as a biostimulant due to its ability to promote growth in cotton plants. Overall, these Trichoderma strains may be used in mixture to provide both pathogen control and promotion of plant growth, and this strategy will support growers in minimizing the use of synthetic fertilizers and fungicides against white mold in cotton crops.

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Microcontact printing using PDMS embossing tools and its variations have aroused the interest of a wide spectrum of research fields, hence the feasibility of defining micro and nanoscale patterns. In this work, we have proposed and demonstrated a novel lithography method based on grayscale patterns printed in a flexographic photopolymer mold and transferred to epoxy resin and a single PDMS stamp to obtain different microprint pattern structures. The geometry of the patterns can be modified by adjusting the layout and grayscale of the stamp patterns. The functionality of this contact printing methodology was validated by generating human induced pluripotent stem cells (hiPSC) patterns. These specific micropatterns can be very useful for achieving complex differentiation in cell lines such as hiPSC. Microfabrication through the new technique provides a promising alternative to conventional lithography for constructing complex aligned surfaces; these structures could be used as components of biological patterns or microfluidic devices.

RESUMO

The common bean (Phaseolus vulgaris L.) is the most important grain legume in the human diet, mainly in Africa and Latin America. Argentina is one of the five major producers of the common bean in the world, and the main cultivation areas are concentrated in the northwestern provinces of this country. Crop production of the common bean is often affected by biotic factors like some endemic fungal diseases, which exert a major economic impact on the region. The most important fungal diseases affecting the common bean in Argentina are white mold caused by Sclerotinia sclerotiorum, angular leaf spot caused by Pseudocercospora griseola, web blight and root rot caused by Rhizoctonia solani, which can cause production losses of up to 100% in the region. At the present, the most effective strategy for controlling these diseases is the use of genetic resistance. In this sense, population study and characterization of fungal pathogens are essential for developing cultivars with durable resistance. In this review we report diversity studies carried out on these three fungal pathogens affecting the common bean in northwestern Argentina, analyzing more than 200 isolates by means of molecular, morphological and pathogenic approaches. Also, the screening of physiological resistance in several common bean commercial lines and wild native germplasm is reviewed. This review contributes to the development of sustainable management strategies and cultural practices in bean production aimed to minimize yield losses due to fungal diseases in the common bean.