Fungal Colonization Patterns Research Articles

Unraveling the interactions of Esteya vermicola, pinewood nematode, and pine hosts: Insights into population dynamics and molecular responses

Esteya vermicola has shown promise as an efficient biological control agent against pine wilt disease, a devastating disease in pine forests caused by the pinewood nematode (PWN, Bursaphelenchus xylophilus). However, the in vivo interactions among E. vermicola, PWN, and pine hosts are less understood, both at the population and molecular levels. In this study, we performed a series of bioassays to investigate E. vermicola colonization patterns in pine xylem and its population responses to PWN invasion in healthy and PWN-induced wilting trees. Our results demonstrated that although E. vermicola exhibits slow growth, its conidia germinate and grew along the pine tracheid, even producing lunate conidia capable of initiating PWN infections within the xylem. Interestingly, while fungal hyphae became undetectable in pine sapling xylem after inoculation, the E. vermicola population increased immediately in response to PWN invasion. Furthermore, we observed a “leap-frog” dispersal pattern of fungal colonization in PWN-induced wilting pines, facilitated by the migration of fungal-infected nematodes. Moreover, we explored the molecular mechanisms underlying fungal tolerance to pine defense systems using transcriptomic analysis. Comparative transcriptomics revealed that carbohydrate metabolism and abiotic stress-induced oxidoreductive activities are involved in the fungal tolerance to the pine defense compound β-pinene. This study enhances our understanding of how E. vermicola colonizes and persists within pine xylem, its molecular responses to plant defense compounds, and its population dynamics upon PWN invasion, validating its efficacy as a biocontrol agent against pine wilt disease.

Fern species and seasonal variation alter arbuscular mycorrhizal fungal colonization and co-occurrence patterns in the Heishiding Natural Reserve, South China

The establishment of arbuscular mycorrhizal fungi (AMF) symbiosis is generally considered an important pathway that assists ferns in their adaption to a variable environment in the forest ecosystem. However, how both fern species and seasonal variation affect the symbiotic characteristics and AMF community structure remains largely unknown. In this study, the AMF colonization status of 19 fern species in the Heishiding Nature Reserve located in south China was assessed. The effects of seasons on AMF colonization and community structure were also determined. The results showed that both seasons and species significantly affected AMF colonization rate (1.88–56.03 %) and spore density (94–546/25 g dry soil). In addition, according to principal component analysis, in spring, AMF colonization and spore density differed considerably from other seasons. The total AMF sequences detected in spring were significantly higher than in winter (p < 0.05). Glomus was the dominant genus, accounting for >75 % of all sequences. The AMF Chao1 and Faith PD indexes of Blechnum orientale Linn as well as the Shannon and Simpson indexes of Selaginella doederleinii Hieron were significantly higher in spring than in winter (p < 0.05). According to partial least squares path modeling, season had a significant influence on AMF colonization by varying the AMF alpha diversity rather than their community composition. Notably, network analysis showed that seasonal variation induced differences in AMF network structure, keystone taxa, and the number of links between species. This study highlights the symbiotic relationship between ferns and AMF in different seasons. The results provide novel insights on terrestrial ecosystem management and fern conservation from the perspective of plant-AM symbiosis.

Fungal diversity and colonization in roots seed trees of Swietenia macrophylla King (Magnoliophyta: Meliaceae) in the tropical rainforest of Laguna Om, Quintana Roo, Mexico

Aim of study: (i) To investigate the diversity of arbuscular mycorrhizal fungi (AMF) associated with the roots of seed trees stands in a conserved and natural population of mahogany (Swietenia macrophylla), based on rDNA sequences; and (ii) to evaluate the dual colonization by AMF and dark septate fungi (DSF), showing the types of fungal colonization patterns in the dry season. Area of study: Tropical rainforest of Ejido Laguna Om, Quintana Roo, Mexico. Material and methods: We evaluated the AMF and DSF colonization in secondary root segments of ten adult trees of mahogany. We analysed the diversity of AMF in one composite sample of mahogany roots (three trees) using 18S rDNA gene with Illumina MiSeq platform. Main results: Through metabarcoding 14 virtual taxa belonging mainly to the genus Glomus and Diversispora were obtained, VTX00186 being the most abundant. The percentages of colonization for the different fungal structures were hyphae 80%, vesicles 18%, coils 2%, and arbuscules 0.5%; for DSF, 60% hyphae and 12% microsclerotia. The Paris-type colonization predominated with 61% in the roots. Research highlights: The knowledge of the AMF diversity present in natural mahogany forests will allow the selection of species for inoculation management seeking to enhance seedling survival and growth of this species.

The Fungal Microbiome of the Upper Airway Is Associated With Future Loss of Asthma Control and Exacerbation Among Children With Asthma

Accumulating evidence suggests that the upper airway bacterial microbiota is implicated in asthma inception, severity, and exacerbation. Unlike bacterial microbiota, the role of the upper airway fungal microbiome (mycobiome) in asthma control is poorly understood. What are the upper airway fungal colonization patterns among children with asthma and their relationship with subsequent loss of asthma control and exacerbation of asthma? The study was coupled with the Step Up Yellow Zone Inhaled Corticosteroids to Prevent Exacerbations (ClinicalTrials.gov Identifier: NCT02066129) clinical trial. The upper airway mycobiome was investigated using Internal transcribed spacer 1 (ITS1) sequencing of nasal blow samples collected from children with asthma when asthma was well controlled (baseline, n= 194) and during early signs of loss of asthma control (yellow zone [YZ], n= 107). At baseline, 499 fungal genera were detected in the upper airway samples, with two commensal fungal species, Malassezia globosa and Malassezia restricta, being most dominant. The relative abundance of Malassezia species varies by age, BMI, and race. Higher relative abundance of M globosa at baseline was associated with lower risk of future YZ episodes (P= .038) and longer time to development of first YZ episode (P= .022). Higher relative abundance of M globosa at YZ episode was associated with lower risk of progression from YZ episode to severe asthma exacerbation (P= .04). The upper airway mycobiome underwent significant changes from baseline to YZ episode, and increased fungal diversity was correlated highly with increased bacterial diversity (ρ= 0.41). The upper airway commensal mycobiome is associated with future asthma control. This work highlights the importance of the mycobiota in asthma control and may contribute to the development of fungi-based markers to predict asthma exacerbation.

Highlighting the Structures and Patterns of Fungal Colonization in the Species Festuca rubra

&#x0D; Grasslands are the most dynamic ecosystems are characterized by high biodiversity both above-ground and underground. The biggest problem in these ecosystems is oligotrophy. The phenomenon affects the stability and resilience of these ecosystems, increasing the impact of biological processes. The symbiotic relationship between plants and mycorrhizas is a natural option with a great impact on maintaining the high natural value of ecosystems. This article aims rating colonization Festuca rubra, dominant in a mountain grassland ecosystem. Roots were cleared and stained with ink for the detection of mycorrhizas in roots. All root samples were analyzed with an optical microscope for the detection of mycorrhizal structures. The results obtained highlight a main mycorrhizal pattern as well as specific subcategories. Both types of arbuscules were identified: Arum and Paris. The results obtained highlight a main mycorrhizal pattern as well as specific subcategories. Vesicles are structures with a constant lack of consistency, which indicates their fluctuating nature. The mycorrhizal pattern of Festuca rubra as the dominant species in the pratol ecosystem may be the first step towards a more detailed understanding of the fungal strategy as well as the increased importance in the stability of the pratol ecosystem. &#x0D;

Molecular Characterization of Fungal Colonization on the Provox™ Tracheoesophageal Voice Prosthesis in Post Laryngec-tomy Patients

Background:Tracheoesophageal voice prostheses (TVPs) have been the gold standard in rehabilitation, after laryngectomy, producing faster and premier voicing towards esophageal speech. Fungal colonization shortens the device’s lifetime and leads to prosthesis dysfunction, leakage, and subsequent respiratory infection. Therefore, in the current study, we aimed to investigate the fungal colonization patterns and to propose prophylactic measures that shall increase the longevity of voice prosthesis.Methods:Failed TVPs were removed - due to leakage and/or aspiration - from 66 post laryngectomy patients and examined. They were referred to Amiralam and Rasoul Hospital, the main centers of Ear, Nose, and Throat in Tehran, Iran from April 2018 to January 2020. Fungal colonization patterns were assessed using DNA sequencing techniques. Furthermore, the susceptibility to fluconazole, amphotericin B, nystatin, and white vinegar was evaluated according to the Clinical and Laboratory Standards Institute (CLSI) guidelines.Results:Resident fungal species from the upper airways colonized all the 66 TVPs (100%). Diabetes (31%) and smoking (98%) were the predominant underlying disease and predisposing factors, respectively. Among the 79 fungal agents isolated from the 66 TVPs, Candida glabrata (n=25, 31.7%) was the most common. A significant reduction in minimum inhibitory concentration (MIC) values were observed for white vinegar when used alone (P<0.05).Conclusion:White vinegar at a very low concentration could decrease the amount of fungal colonization on TVPs without any adverse effects; its wide accessibility and affordability ensure a decrease in the overall health cost.

Morpho-anatomical differences among mycoheterotrophic Afrothismia spp. (Thismiaceae) indicate an evolutionary progression towards improved mycorrhizal benefit

Achlorophyllous, mycoheterotrophic plants depend on their mycorrhizal fungi for 100% of their carbon supply. Hence, there is strong evolutionary pressure towards a well-organized functioning of the association from the plant’s perspective. Members of the mycoheterotrophic genus Afrothismia have evolved elaborate fungal colonization patterns allowing a sustained benefit from external fungal penetration events. On the basis of anatomical details of the root-shoot systems of A. korupensis and A. hydra, we elucidate an evolutionary progression between the comparatively simple mycorrhizal pattern in A. gesnerioides and the so far most complex mycorrhiza in A. saingei. We detected two major advancements: (1) two species, A. korupensis and A. saingei, use the fungus itself as energy storage, replacing starch depositions used by A. gesnerioides and A. hydra, and (2) the morphological complexity of hyphal forms in plant tissue compartments increases from A. gesnerioides to A. saingei. We discuss the omitting of starch metabolism as well as the morpho-anatomical differences as an evolutionary fine-tuning of the compartmented mycorrhizal organization in Afrothismia. Our results support the idea of a taxonomic distinction between Afrothismia and other Thismiaceae.

Fungal colonization patterns and enzymatic activities of peatland ericaceous plants following long-term nutrient addition

Northern peatlands are often dominated by ericaceous shrub species which rely on ericoid mycorrhizal fungi (ERM) for access to organic sources of nutrients, such as nitrogen (N) and phosphorus (P), and host abundant dark septate endophytes (DSE). Relationships between hosts and fungal symbionts may change during deposition of anthropogenic N and P. We studied the long-term effects of N and P addition on two ericaceous shrubs, Calluna vulgaris and Erica tetralix, at Whim Bog, Scotland by analyzing fungal colonization of roots, enzymatic activity, and fungal species composition. Unexpectedly, the frequency of typical ERM intracellular colonization did not change while the occurrence of ERM hyphae tended to increase and DSE hyphae to decrease. Our findings indicate that altered nutrient limitations shift root associated fungal colonization patterns as well as affect ericaceous root enzyme activity and thereby decomposition potential. Reduction of recalcitrant fungal biomass in melanized DSE may have implications for peatland C sequestration under nutrient addition.

Root cortical anatomy is associated with differential pathogenic and symbiotic fungal colonization in maize.

Root anatomical phenotypes vary among maize (Zea mays) cultivars and may have adaptive value by modifying the metabolic cost of soil exploration. However, the microbial trade-offs of these phenotypes are unknown. We hypothesized that nodal roots of maize with contrasting cortical anatomy have different patterns of mutualistic and pathogenic fungal colonization. Arbuscular mycorrhizal colonization in the field and mesocosms, root rots in the field, and Fusarium verticillioides colonization in mesocosms were evaluated in maize genotypes with contrasting root cortical anatomy. Increased aerenchyma and decreased living cortical area were associated with decreased mycorrhizal colonization in mesocosm and field experiments with inbred genotypes. In contrast, mycorrhizal colonization of hybrids increased with larger aerenchyma lacunae; this increase coincided with larger root diameters of hybrid roots. F. verticillioides colonization was inversely correlated with living cortical area in mesocosm-grown inbreds, and no relation was found between root rots and living cortical area or aerenchyma in field-grown hybrids. Root rots were positively correlated with cortical cell file number and inversely correlated with cortical cell size. Mycorrhizae and root rots were inversely correlated in field-grown hybrids. We conclude that root anatomy is associated with differential effects on pathogens and mycorrhizal colonization of nodal roots in maize.

Culture-based identification to examine spatiotemporal patterns of fungal communities colonizing wood in ground contact

ABSTRACTTimber durability is often assessed using small wood stakes exposed in direct soil contact, and the assessment generally emphasizes effects on wood rather than organisms involved. Understanding fungal colonization patterns can help identify key decay agents under varying conditions and use these patterns to improve wood protection strategies. Fungal colonization of red alder (Alnus rubra), Douglas-fir (Pseudotsuga menziesii) heartwood/sapwood, and western redcedar (Thuja plicata) field stakes was assessed over 2 y in western Oregon. Spatiotemporal fungal community variations were identified via culturing and DNA sequencing, where 814 isolates were identified from 84 stakes. Forty-six ascomycete genera were identified, with Phialophora, Trichoderma, and Epicoccum species occurring most frequently. Twenty-three basidiomycete genera were identified, with Trametes and Phanerochaete being the most common. Douglas-fir and western redcedar stakes contained the highest and lowest diversity levels, respectively, reflecting natural durability differences of these species. Fungal species abundance was higher below ground than in the above ground and groundline zones, likely reflecting more stable moisture regimes, proximity to soil-based fungi, and potential nutrient migration into wood beneath the soil surface. Ascomycetes were proportionally more abundant early in the exposure period, but basidiomycetes were also observed early in the process, and there appeared to be no consistent colonization pattern.

Fungal colonization of plant roots is resistant to nitrogen addition and resilient to dominant species losses

AbstractGlobal change drivers, such as nitrogen (N) deposition and non‐random species extinctions, may shift interactions among aboveground and belowground communities. However, tightly coupled interactions between aboveground and belowground organisms may buffer ecosystems to global change. Here, we test how four years of organic and inorganic N addition and removal of a dominant plant species, Festuca thurberi, independently and interactively influences fungal colonization patterns and performance in a co‐dominant plant species, Helianthella quinquenervis. Surprisingly, we found N addition and Festuca removal had no measurable effects on the colonization of arbuscular mycorrhizal fungi (AMF) and dark septate endophyte (DSE) or the performance of Helianthella seedlings grown with field‐collected inoculum in a companion greenhouse experiment. However, the proximity of Helianthella to Festuca predicted fungal colonization: DSE colonization decreased by 1% for each cm of distance Helianthella was from Festuca, although the differences in fungal inoculum potential had no effect on Helianthella seedling survival or biomass. Our results suggest that plant–fungal interactions can be resistant to N addition and resilient to the loss of dominant plant species. Additionally, our results suggest that soil legacies, mediated through surviving symbiont communities or changes in soil properties, can shape ecosystem resistance and resilience to disturbance and perturbations.

Fungal colonization patterns of wood exposed out of soil contact in Western Oregon

Wood is among the most decay-resistant cellulosic materials; however, all organics eventually succumb to decay. Understanding the degradation process is important when considering how products perform, but this knowledge can also be useful when determining how climates affect the organisms involved and the rates at which degradation occurs. Above ground wood decay tends to occur more slowly than decay in direct soil contact and is more dependent on climatic differences and wood species chemistries. While above ground wood deterioration is a subject of interest, most research has concentrated on the effects of the organisms on the wood. There are surprisingly few comprehensive studies of the fungi involved in the process and most have been performed under aggressive tropical conditions. Fungal colonization of red alder and Douglas-fir samples exposed above ground was evaluated over a 24-month period. Red alder is highly susceptible to fungal attack while Douglas-fir is moderately resistant. As such, they presented two differing selective media for fungal colonization. Red alder was more heavily colonized than Douglas-fir, reflecting the differing susceptibility of the two wood species to degradation. A similar number of Ascomycete and Basidiomycete species were isolated (11 vs 8 species, respectively), but Basidiomycetes were more frequently isolated. These results were similar to those found under more tropical conditions. The results illustrate the wide range of species that colonize wood exposed above ground.

Fungal succession and decomposition of composted aquatic plants applied to soil

Abstract Few studies have documented the pattern of fungal colonization and decomposition of composted aquatic plants applied for amending soil. In the present study, we demonstrated the fungal succession and its relationship with chemical changes in decomposing composted aquatic plants applied to soil, by performing a 6-month litterbag experiment incubating three types of composted aquatic plants differing in the years of composting. A total of 189 operational taxonomic units (OTUs) of fungi were detected, including 115 and 34 OTUs in Ascomycota and Basidiomycota, respectively. The OTU richness generally increased with the progression of decomposition and was not significantly different among the three types of composted aquatic plants. Redundancy analysis indicated the relationships among the fungal assemblages, type of composted aquatic plants, duration of decomposition, and chemical changes in composted aquatic plants. Fungal succession was generally characterized by the cumulative increase of major OTUs and was affected by the contents of extractives, total carbohydrates, total carbon, and total nitrogen in decomposing composted aquatic plants.

Development of three fusarium crown rot causal agents and systemic translocation of deoxynivalenol following stem base infection of soft wheat

Fusarium pseudograminearum, F. culmorum and F. graminearum are the most important fusarium crown rot (FCR) causal agents. They have the common ability to biosynthesize deoxynivalenol (DON). To elucidate the behaviour of each of the three species, a comparative study was carried out to investigate symptom progression, fungal systemic growth and translocation of DON following stem base inoculation of soft wheat. FCR symptoms were mainly localized in the inoculated area, which extended up to the second node for all inoculated species. Only the most aggressive strains caused symptoms up to the third node. Real‐time quantitative PCR showed that fungal colonization reached the third node for all the tested species, but a low percentage of plants showed colonization above the third node following inoculation with the most aggressive strains. Fungal growth was detected in symptomless tissues but none of the three species was able to colonize as far as the head tissues. However, even if the pathogens were not detected in the heads, DON was detected in head tissues of the plants inoculated with the most aggressive strains. These results demonstrate that F. pseudograminearum, F. culmorum and F. graminearum, under the same experimental conditions, follow a similar pattern of symptom progression, fungal colonization and DON translocation after stem base infection. Differences in the extent of symptoms, fungal colonization and mycotoxin distribution were mainly attributable to strain aggressiveness. These findings provide comparative information on the events following infection of the stem base of wheat by three of the most important FCR casual agents.

Epidemiology and Resistance Patterns of Bacterial and Fungal Colonization of Biliary Plastic Stents: A Prospective Cohort Study.

BackgroundPlastic stents used for the treatment of biliary obstruction will become occluded over time due to microbial colonization and formation of biofilms. Treatment of stent-associated cholangitis is often not effective because of inappropriate use of antimicrobial agents or antimicrobial resistance. We aimed to assess the current bacterial and fungal etiology of stent-associated biofilms, with particular emphasis on antimicrobial resistance.MethodsPatients with biliary strictures requiring endoscopic stent placement were prospectively enrolled. After the retrieval of stents, biofilms were disrupted by sonication, microorganisms were cultured, and isolates were identified by matrix-associated laser desorption/ionization time-of-flight (MALDI-TOF) mass spectrometry and/or biochemical typing. Finally, minimum inhibitory concentrations (MICs) were determined for various antimicrobial agents. Selected stents were further analyzed by fluorescence in situ hybridization (FISH).ResultsAmong 120 patients (62.5% males, median age 64 years) with biliary strictures (35% malignant, 65% benign), 113 double pigtail polyurethane and 100 straight polyethylene stents were analyzed after a median indwelling time of 63 days (range, 1–1274 days). The stent occlusion rate was 11.5% and 13%, respectively, being associated with a significantly increased risk of cholangitis (38.5% vs. 9.1%, P<0.001). Ninety-five different bacterial and 13 fungal species were detected; polymicrobial colonization predominated (95.8% vs. 4.2%, P<0.001). Enterococci (79.3%), Enterobacteriaceae (73.7%), and Candida spp. (55.9%) were the leading pathogens. Candida species were more frequent in patients previously receiving prolonged antibiotic therapy (63% vs. 46.7%, P = 0.023). Vancomycin-resistant enterococci accounted for 13.7%, extended-spectrum beta-lactamase (ESBL)-producing Enterobacteriaceae with co-resistance to ciprofloxacin accounted for 13.9%, and azole-resistant Candida spp. accounted for 32.9% of the respective isolates.ConclusionsEnterococci and Candida species play an important role in the microbial colonization of biliary stents. Therefore, empirical antimicrobial treatment of stent-associated cholangitis should be guided toward enterococci, Enterobacteriaceae, streptococci, anaerobes, and Candida. To determine causative pathogens, an accurate microbiological analysis of the extracted stent(s) may be helpful.

Microbial colonization and lung function in adolescents with cystic fibrosis

With intensified antibiotic therapy and longer survival, patients with cystic fibrosis (CF) are colonized with a more complex pattern of bacteria and fungi. However, the clinical relevance of these emerging pathogens for lung function remains poorly defined. The aim of this study was to assess the association of bacterial and fungal colonization patterns with lung function in adolescent patients with CF. Microbial colonization patterns and lung function parameters were assessed in 770 adolescent European (German/Austrian) CF patients in a retrospective study (median follow-up time: 10years). Colonization with Pseudomonas aeruginosa and MRSA were most strongly associated with loss of lung function, while mainly colonization with Haemophilus influenzae was associated with preserved lung function. Aspergillus fumigatus was the only species that was associated with an increased risk for infection with P. aeruginosa. Microbial interaction analysis revealed three distinct microbial clusters within the longitudinal course of CF lung disease. Collectively, this study identified potentially protective and harmful microbial colonization patterns in adolescent CF patients. Further studies in different patient cohorts are required to evaluate these microbial patterns and to assess their clinical relevance.

Biotic and abiotic predictors of fungal colonization in grasses of the Colorado Rockies

AbstractAimFungal symbionts are ubiquitous in plants and can mitigate abiotic stressors associated with climate change. Predicting fungal symbiont distributions under future climates first requires knowledge of current distributions and their potential drivers.LocationWe documented colonization by fungal symbionts in perennial, cool‐season grasses along altitudinal gradients in the Rocky Mountains of Colorado, USA.MethodsAcross seven replicate altitudinal gradients, spanning c. 1400 vertical meters, we scored fungal colonization for 46 grass species. We documented altitudinal clines in colonization by both above‐ground and below‐ground fungal symbionts for the first time, including localized foliar endophytes (LFE) and systemic endophytes (epichloae) in leaves and arbuscular mycorrhizal fungi (AMF) and dark septate endophytes (DSE) in roots. For a subset of 16 well‐sampled grass species, we used model selection procedures to evaluate the relative importance of geography, edaphic factors and host plant identity. We also assessed the influence of host phylogenetic relatedness and colonization by co‐infecting fungi.ResultsLevels of fungal colonization varied strongly with host plant identity, but the effects of particular host species were not consistent across fungal groups. In addition to the influence of host identity, epichloae colonization declined with elevation and varied with geography (latitude/longitude) and edaphic factors. Geography and collection date were important predictors of LFE colonization, with higher colonization later in the growing season. Colonization estimates for the obligately plant‐associated fungi (epichloae, AMF) were phylogenetically conserved across the grass supertree. Positive correlations between AMF and DSE, which remained even after accounting for host plant relatedness, suggested possible synergisms between these fungal groups.Main conclusionsOur survey showed greater host specificity in patterns of fungal colonization than prior reports and revealed that different fungal symbiont groups do not share similar drivers. Conserving plant–fungal symbioses under future climates may require unique strategies for different plant species and fungal symbiont types.

Different Gene Expressions of Resistant and Susceptible Hop Cultivars in Response to Infection with a Highly Aggressive Strain of Verticillium albo-atrum.

Verticillium wilt has become a serious threat to hop production in Europe due to outbreaks of lethal wilt caused by a highly virulent strain of Verticillium albo-atrum. In order to enhance our understanding of resistance mechanisms, the fungal colonization patterns and interactions of resistant and susceptible hop cultivars infected with V. albo-atrum were analysed in time course experiments. Quantification of fungal DNA showed marked differences in spatial and temporal fungal colonization patterns in the two cultivars. Two differential display methods obtained 217 transcripts with altered expression, of which 84 showed similarity to plant proteins and 8 to fungal proteins. Gene ontology categorised them into cellular and metabolic processes, response to stimuli, biological regulation, biogenesis and localization. The expression patterns of 17 transcripts with possible implication in plant immunity were examined by real-time PCR (RT-qPCR). Our results showed strong expression of genes encoding pathogenesis-related (PR) proteins in susceptible plants and strong upregulation of genes implicated in ubiquitination and vesicle trafficking in the incompatible interaction and their downregulation in susceptible plants, suggesting the involvement of these processes in the hop resistance reaction. In the resistant cultivar, the RT-qPCR expression patterns of most genes showed their peak at 20 dpi and declined towards 30 dpi, comparable to the gene expression pattern of in planta detected fungal protein and coinciding with the highest fungal biomass in plants at 15 dpi. These expression patterns suggest that the defence response in the resistant cultivar is strong enough at 20 dpi to restrict further fungus colonization.Electronic supplementary materialThe online version of this article (doi:10.1007/s11105-014-0767-4) contains supplementary material, which is available to authorized users.

The prevalence of fungal infections in a level I Iranian burn hospital

Background: With significant increase in incidence of fungal infections in burn victims, determination of patternof fungal infections and colonization is required to allow medical staff to begin proper empirical antibiotic therapyin early stages of septic episodes. Objective: To determine the current infection profile (especially fungal profile) of burn wounds in a level I burncare center in Tehran. Methods: A cross-sectional survey was conducted from January 2008 to September 2009 on burn wound patientsadmitted in Shahid Motahari Burn Hospital, Tehran, Iran. Wound swab cultures and tissue specimens from 869patients (634 male and 235 female) out 4083 were taken and cultured in Sabouraud dextrose agar. The fungalorganisms were then identified with macroscopic and microscopic structures. Results: The incidence of fungal infection (not colonization) among the patients of this study was 13%.Candida albicans was identified as the dominant fungal agent (45%) followed by Aspergillus fumigatus (35%),Penicillium (8%), Aspergillus niger (5%), and other fungal organisms (7%). Conclusion: With such high mortality rate and an increasing incidence of fungal wound infections, fungalinfections should be a top infectious complication of burn patients and should be managed immediately andaggressively. Keywords: Burn wound, Candida albicans, colonization, fungal infection, incidence

Profiling functions of ectomycorrhizal diversity and root structuring in seedlings of Norway spruce (Picea abies) with fast‐ and slow‐growing phenotypes

We studied the role of taxonomical and functional ectomycorrhizal (ECM) fungal diversity in root formation and nutrient uptake by Norway spruce (Picea abies) seedlings with fast- and slow-growing phenotypes. Seedlings were grown with an increasing ECM fungal diversity gradient from one to four species and sampled before aboveground growth differences between the two phenotypes were apparent. ECM fungal colonization patterns were determined and functional diversity was assayed via measurements of potential enzyme activities of eight exoenzymes probably involved in nutrient mobilization. Phenotypes did not vary in their receptiveness to different ECM fungal species. However, seedlings of slow-growing phenotypes had higher fine-root density and thus more condensed root systems than fast-growing seedlings, but the potential enzyme activities of ectomycorrhizas did not differ qualitatively or quantitatively. ECM species richness increased host nutrient acquisition potential by diversifying the exoenzyme palette. Needle nitrogen content correlated positively with high chitinase activity of ectomycorrhizas. Rather than fast- and slow-growing phenotypes exhibiting differing receptiveness to ECM fungi, our results suggest that distinctions in fine-root structuring and in the belowground growth strategy already apparent at early stages of seedling development may explain later growth differences between fast- and slow-growing families.