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Panax ginseng C. A. Meyer is one of the most important medicinal herbs in China. It is known for its high medicinal value and economic value. The ginseng root rust rot (RRR) has always been one of the important diseases troubling the ginseng industry. The yield reduction rate of RRR is ~30%. To understand why the Cylindrocarpon species bring about the ginseng RRR in Northeastern China, this study isolates 45 strains from samples collected in Liaoning, Jilin, and Heilongjiang provinces. The rDNA-internal transcribed spacer (ITS) sequence was analyzed to identify the pathogenic species. The morphological characteristics of colonies and conidia of each strain on potato dextrose agar (PDA) medium were observed, and the pathogenicity difference between different pathogenic species was analyzed by pricking method and determining the cell wall degrading enzyme activity. The BLAST alignment analysis shows that the homology of rDNA-ITS between 45 strains and Cylindrocarpon is more than 99%, among which 28 are identified as Cylindrocarpon destructans , three are identified as C. destructans var. destructans , and 14 are identified as Ilyonectria robusta. The colony diameters of all 45 isolated range from 4.21 ± 0.16a to 7.78 ± 0.25c cm after several days of incubation. Among all the species, I. robusta has the fastest growth rate, and C. destructans var. destructans has the slowest growth rate. Pathogenicity test results show that the pathogenicity of C. destructans var. destructans is the strongest, followed by C. destructans. I. robusta has relatively weak pathogenicity. [ABSTRACT FROM AUTHOR]

Panax ginseng C. A. Meyer is one of the most important medicinal herbs in China. It is known for its high medicinal value and economic value. The ginseng root rust rot (RRR) has always been one of the important diseases troubling the ginseng industry. The yield reduction rate of RRR is ~30%. To understand why the Cylindrocarpon species bring about the ginseng RRR in Northeastern China, this study isolates 45 strains from samples collected in Liaoning, Jilin, and Heilongjiang provinces. The rDNA-internal transcribed spacer (ITS) sequence was analyzed to identify the pathogenic species. The morphological characteristics of colonies and conidia of each strain on potato dextrose agar (PDA) medium were observed, and the pathogenicity difference between different pathogenic species was analyzed by pricking method and determining the cell wall degrading enzyme activity. The BLAST alignment analysis shows that the homology of rDNA-ITS between 45 strains and Cylindrocarpon is more than 99%, among which 28 are identified as Cylindrocarpon destructans, three are identified as C. destructans var. destructans, and 14 are identified as Ilyonectria robusta. The colony diameters of all 45 isolated range from 4.21 ± 0.16a to 7.78 ± 0.25c cm after several days of incubation. Among all the species, I. robusta has the fastest growth rate, and C. destructans var. destructans has the slowest growth rate. Pathogenicity test results show that the pathogenicity of C. destructans var. destructans is the strongest, followed by C. destructans. I. robusta has relatively weak pathogenicity.

Fusarium species are among the most commonly isolated causes of fungal keratitis. Most species of the genus Fusarium belong to Fusarium solani species complex (FSSC). Fusarium lichenicola, a member of the FSSC complex, is a well-established plant and human pathogen. However, reports of fungal keratitis due to Fusarium lichenicola have not been frequently reported. To the best of our knowledge, only twelve cases of Fusarium lichenicola keratitis have been reported in the past fifty years. Clinical cases of Fusarium lichenicola may have most likely been misidentified because of the lack of clinical and microbiological suspicion, as well as inadequate diagnostic facilities in many tropical countries where the burden of the disease may be the highest. We report a case of fungal keratitis caused by Fusarium lichenicola and present a global review of the literature of all cases of fungal keratitis caused by this potentially blinding fungus. [ABSTRACT FROM AUTHOR]

Black foot disease of grapevines is a major economic issue for the viticulture industry worldwide. The disease is mainly associated with a complex of pathogen species within the genera Dactylonectria and Ilyonectria. The susceptibility of six grapevine rootstock cultivars to black foot disease under field conditions was assessed. Callused rootstocks of 101-14, 5C, 420A, Riparia Gloire, Schwarzmann and 3309C were planted into soil containing low natural pathogen populations or inoculated with isolates representing the species diversity in New Zealand. Disease incidence, disease severity and dry weight accumulation were assessed after 8 months of growth. Root and shoot dry weights were not significantly affected by inoculation treatment, but differed among rootstock cultivars, with cultivar 420A having the lowest root and shoot dry weight, cultivar 3309C having the largest shoot dry weight and cultivar 5C the largest root dry weight. The relative susceptibility of rootstocks differed significantly depending on whether they were grown under low natural inoculum pressure or a higher pressure in artificially inoculated soil. Schwarzmann and Riparia Gloire rootstock cultivars were the least susceptible under natural low inoculum pressure, but were the most susceptible in inoculated soil. In contrast, 5C was one of the most susceptible under low inoculum levels but was the least susceptible under high pathogen pressure. The result of the study indicate that black foot pathogen inoculum levels in soil affect the relative susceptibility of grapevine rootstocks to infection, and may have implications for the selection of rootstocks for planting. [ABSTRACT FROM AUTHOR]

Cylindrocarpon root rot is caused by “Cylindrocarpon destructans”/ “Ilyonectria destructans”. The bibliometric analysis had been conducted to understand the active authors, organizations, journals, and countries involved in the research domain of “Cylindrocarpon root rot”. All published articles related to “Cylindrocarpon root rot” from “Scopus”, were analyzed using the VOS viewer to develop analysis tables and visualization maps. This article had set the objective to consolidate the scientific literature regarding the “Cylindrocarpon root rot” and also to find out the trends related to the same. The most active journals in this research domain were identified as Mycological Progress, European Journal of Plant Pathology, and Phytopathology. The most active countries were South Korea, Canada, and Portugal. The leading organization engaged in the research domain was The Department of Agriculture and Agri-Food of Canada. The most active authors were Yang D.-C, Reeleder R.D., and Li Y. [ABSTRACT FROM AUTHOR]

Grapevine trunk diseases (GTDs) are one of the most important groups of fungal diseases affecting grapevine plants worldwide. One of the main causes of GTDs infection occur during nursery plant production processes. The phytosanitary status was determined for 150 young grapevine plants (two varieties grafted onto different rootstocks) that were produced in three European nurseries. Some plants were analyzed upon submission, while others were assessed after up to 12 months growth in a greenhouse. Fungal species associated with GTDs were identified and characterized from the scions, graft unions, rootstocks, or roots. A total of 449 fungal isolates associated with GTDs were obtained, and 20 species were identified by morphological characteristics and DNA analyses. Five species were involved in Botryosphaeria dieback, six in black foot disease, six in Diaporthe dieback, and three in Petri disease. Incidence of GTDs on grapevine plants was between 81 and 100%, with different diseases varying between rootstocks and grapevine varieties. Isolates of other fungal genera not involved in the GTD complex were also detected, including Colletotrichum, Fusarium, and Rhizoctonia. The high presence of GTDs during nursery production of grapevine plants raises the need to implement effective control methods that could prevent the spread of these diseases to vineyards.

Grapevine trunk diseases (GTDs) are one of the most important groups of fungal diseases affecting grapevine plants worldwide. One of the main causes of GTDs infection occur during nursery plant production processes. The phytosanitary status was determined for 150 young grapevine plants (two varieties grafted onto different rootstocks) that were produced in three European nurseries. Some plants were analyzed upon submission, while others were assessed after up to 12 months growth in a greenhouse. Fungal species associated with GTDs were identified and characterized from the scions, graft unions, rootstocks, or roots. A total of 449 fungal isolates associated with GTDs were obtained, and 20 species were identified by morphological characteristics and DNA analyses. Five species were involved in Botryosphaeria dieback, six in black foot disease, six in Diaporthe dieback, and three in Petri disease. Incidence of GTDs on grapevine plants was between 81 and 100%, with different diseases varying between rootstocks and grapevine varieties. Isolates of other fungal genera not involved in the GTD complex were also detected, including Colletotrichum, Fusarium, and Rhizoctonia. The high presence of GTDs during nursery production of grapevine plants raises the need to implement effective control methods that could prevent the spread of these diseases to vineyards. [ABSTRACT FROM AUTHOR]

Cylindrocarpon-like asexual morphs infect herbaceous and woody plants, mainly in agricultural scenarios, but also in forestry systems. The aim of the present study was to characterize a collection of Cylindrocarpon-like isolates recovered from the roots of a broad range of forest hosts from nurseries showing decline by morphological and molecular studies. Between 2009 and 2012,17 forest nurseries in Spain were surveyed and a total of 103 Cylindrocarpon-like isolates were obtained. Isolates were identified based on DNA sequences of the partial gene regions histone H3 (his3). For the new species, the internal transcribed spacer and intervening 5.8S nrRNA gene (ITS) region, (3-tubulin (Iub2), and translation elongation factor I-a (tefl) were also used to determine their phylogenetic position. Twelve species belonging to the genera Cylindrodendrum, Dactylonectria, and llyonectria were identified from damaged roots of 15 different host genera. The species C. alicantinum, D. macrodidyma, D. novozelandica, D. pauciseptata, D. pinícola, D. torresensis, I. capensis, I. cyclaminicola, I. liriodendri, 1. pseudodestructans, I. robusta, and I. rufa were identified. In addition, two Dactylonectria species (D. hispánico sp. nov. and D valentina sp. nov.), one llyonectria species (I. ilicicola sp. nov.), and one Neonectria species (N. quercicola sp. nov.) are newly described. The present study demonstrates the prevalence of this fungal group associated with seedlings of diverse hosts showing decline symptoms in forest nurseries in Spain. [ABSTRACT FROM AUTHOR]

Activated sludge microbial community composition is a key bio-indicator of the sustainability of wastewater treatment systems. Therefore, a thorough understanding of the activated sludge microbial community dynamics is critical for environmental engineers to effectively manage the wastewater treatment plants (WWTPs). However, fungal communities associated with activated sludge have been poorly elucidated. Here, the activated sludge fungal community in 18 geographically distributed WWTPs was determined by using Illumina sequencing. The results showed that differences in activated sludge fungal community composition were observed among all WWTPs and also between oxidation ditch and anaerobic-anoxic-aerobic (A/A/O) systems. Ascomycota was the largest phyla, followed by Basidiomycota in all samples. Sporidiobolales and Pezizales were the most abundant order in oxidation ditch and A/A/O systems, respectively. The network analysis indicated cooperative and co-occurrence interactions between fungal taxa in order to accomplish the wastewater treatment process. Hygrocybe sp., Sporobolomyces sp., Rhodotorula sp., Stemphylium sp., Parascedosporium sp., and Cylindrocarpon sp., were found to have statistically significant interactions. Redundancy analysis revealed that temperature, total phosphorus, pH, and ammonia nitrogen were significantly affected the fungal community. This study sheds light on providing the ecological characteristics of activated sludge fungal communities and useful guidance for improving wastewater treatment performance efficiency. [ABSTRACT FROM AUTHOR]

Crop decline is a progressive soil health reduction commonly associated to the specialized cultivations. As a series of biotic factors are involved in this phenomenon, it can be controlled with essentially agronomic methods, the impact of winter cover crops on early growth at subsequent vegetable crops was investigated in a two-year field study. Barley and hairy vetch were incorporated into the soil following two mechanical terminations of cover crops (green manure and green mulching). Immediately after, tomato and zucchini seedlings were transplanted and grown for 28 days. The above-ground biomass of the vegetables was taken as indicator of crop response to pre-plant treatments, whilst root colonizing fungi and rhizosphere bacteria were the two analyzed soil microbial components. Root-colonizing fungi were evaluated using culture-based methods, bacteria were analyzed by amplification of rhizosphere soil DNA with 16S rDNA, then processed with PCR-DGGE. Tomato and zucchini growth response after vetch was always significantly higher than after barley regardless of mechanical termination. Rhizosphere bacterial communities differed significantly between cover crops and this differences was maintained also in the subsequent vegetable crops. Root-colonizing fungi differed between barley and vetch, although they shared most species (70%) such as Pythium spp., binucleate Rhizoctonia AG-A and several Fusarium spp. The latter three fungal groups were also found most abundant in tomato and zucchini roots. Pathogenicity test showed that tomato was more susceptible than zucchini to Pythium , Rhizoctonia solani , Fusarium oxysporum and Fusarium spp. and that their relationship with vegetable plants varied from pathogenic to neutral, up to mutualistic in the case of Rhizoctonia AG-A. These findings indicate difficulty to identify specific biotic agents responsible of crop decline. Tomato and zucchini showed an undoubted growth improvement after legume; however, a certain specificity of Cylindrocarpon -like fungi and Phoma spp. to hairy vetch suggests that, when exploiting benefit of this cover crop for mitigating yield decline of vegetable crops, legume should alternate cereal and other botanically distant genera in rotation. [ABSTRACT FROM AUTHOR]

Bio-transformed volatile compounds in horse gram sprouts, Lactobacillus plantarum NRRL B-4496 and Lactobacillus plantarum NCDO 1193 mediated as well as naturally fermented horse gram sprouts were analyzed using gas chromatography-mass spectrometry coupled with headspace solid-phase micro extraction. A total of 36 compounds, including acids, alcohols, aldehydes, esters, ketones, sulfur containing compounds were identified in sprouts fermented for 1, 2, 3, 4 and 5 days by mass spectral data, Kovats indices and comparing authentic standards. Fermentation-mediated volatile metabolites such as acetic acid, eugenol, benzyl alcohol (benzene methanol), acetoin, 2, 3-butanediol and ethyl palmitate were found to be the prime contributors to the sensory attributes of fermented samples. As the contents of alcohols, ketones, esters and phenols increased during fermentation, some aldehydes significantly decreased. For the first time, eugenol was detected in fermentation of horse gram, paving the way for new bioprocessing strategy for production of health beneficial aroma compound. Therefore, fermentation of horse gram sprouts enhances bio-transformed volatile composition derived from primary metabolites which has relevance for improving value-added flavor and health benefits from short chain fatty acids while integrating potential probiotic benefits. [ABSTRACT FROM AUTHOR]

To investigate the role that ginsenosides (and some of their metabolites) play in interactions between plants and phytopathogenic fungi (e.g. Cylindrocarpon destructans (Zinss) Scholten), we systematically determined the anti-fungal activities of six major ginsenosides (Rb 1 , Rb 2 , Rc, Rd, Re and Rg 1 ), along with the metabolites of ginsenoside Rb 1 (Gypenoside XVII (G-XVII) and F 2 ), against the ginseng root pathogen C. destructans (Zinss) Scholten and non-ginseng pathogens Fusarium graminearum Schw., Exserohilum turcicum (Pass.) Leonard et Suggs, Phytophthora megasperma Drech. and Pyricularia oryzae Cav. Our results showed that the growth of both ginseng pathogens and non-pathogens could be inhibited by using the proto-panaxatriol (PPT) ginsenosides Re and Rg 1 . In addition, the growth of the non-pathogens could also be inhibited by using proto-panaxadiol (PPD) ginsenosides Rb 1 , Rb 2 , Rc and Rd, whereas the growth of ginseng pathogen C. destructans (Zinss) Scholten was enhanced by ginsenosides Rb 1 and Rb 2 . In contrast, ginsenoside G-XVII and F 2 strongly inhibited the hyphal growth of both C. destructans (Zinss) Scholten and the non-pathogens tested. Furthermore, addition of sucrose to the media increased the growth of C. destructans (Zinss) Scholten, whereas glucose did not affect the growth. Moreover, C. destructans (Zinss) Scholten and all four non-pathogens were able to deglycosylate PPD ginsenosides using a similar transformation pathway, albeit with different sensitivities. We also discussed the anti-fungal structure-activity relationships of the ginsenosides. Our results suggest that the pathogenicity of C. destructans (Zinss) Scholten against ginseng root is independent of its ability to deglycosylate ginsenosides. [ABSTRACT FROM AUTHOR]

Introduction: We report a rare cause of keratitis, due to Cylindrocarpon lichenicola, in a farmer with keratomycosis. Despite the acknowledged virulence of this fungus, a suitable antifungal for its management was not accessible. Case presentation: A 67-year-old farmer presented with a two-week history of pain, mucopurulent discharge, redness and a corneal ulcer with a visual acuity of hand movement in the right eye. With a working diagnosis of infective keratitis, corneal scrapings were taken under a slit lamp biomicroscope for microbiological testing. Direct lactophenol cotton blue mounts revealed septate fungal hyphae, while fungal culture on Sabouraud dextrose agar at room temperature grew woolly mould phenotypically consistent with C. lichenicola. Management and outcome: The patient was started on hourly topical natamycin (5%), ciprofloxacin (0.3%), two-hourly instillation of tobramycin (0.3%) and atropine (1%) twice daily for three months following the isolation of the fungus. The eye healed with a corneal scar and no improvements in visual acuity. Discussion: This infection was difficult to manage due to the inaccessibility of a suitable antifungal, namely, voriconazole in our setting. Hence, there is a need for prompt identification and early institution of suitable antifungals in any patient with suspected keratomycosis.

Cylindrocarpon destructans is an ascomycete soil-borne pathogen that causes ginseng root rot. To identify effective biocontrol agents, we isolated several bacteria from ginseng cultivation soil and evaluated their antifungal activity. Among the isolated bacteria, one isolate (named JH7) was selected for its high antibiotic activity and was further examined for antagonism against fungal pathogens. Strain JH7 was identified as a Chromobacterium sp. using phylogenetic analysis based on 16S rRNA gene sequences. This strain was shown to produce antimicrobial molecules, including chitinases and proteases, but not cellulases. Additionally, the ability of JH7 to produce siderophore and solubilize insoluble phosphate supports its antagonistic and beneficial traits for plant growth. The JH7 strain suppressed the conidiation, conidial germination, and chlamydospore formation of C. destructans. Furthermore, the JH7 strain inhibited other plant pathogenic fungi. Thus, it provides a basis for developing a biocontrol agent for ginseng cultivation. [ABSTRACT FROM AUTHOR]

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Aims The effect of Bacillus amyloliquefaciens AK-0 ( AK-0) on ginseng root rot disease caused by Cylindrocarpon destructans was investigated. Methods and Results From 190 ginseng rhizosphere bacteria, AK-0 was selected for further analysis; its morphological characteristics were investigated by microscopy. AK-0 was identified as B. amyloliquefaciens using the Biolog system, 16S rRNA gene sequence analysis and examination of morphological and biochemical characteristics. Bacterial population and media optimization were estimated by the bacterial growth curve. The number of AK-0 cells was relatively higher in brain-heart infusion ( BHI) medium than in other media. The potential antifungal effect of AK-0 culture filtrate on the in vitro conidial germination of C. destructans and root rot development on root discs and 4-year-old ginseng roots were assessed. Polymerase chain reaction ( PCR) analysis of antibiotic biosynthesis gene expression suggested that the release of antibiotic compounds is involved in the antifungal effect of AK-0 and the suppression of ginseng root rot. Conclusion These results indicate that the CF of AK-0 has antifungal effects on fungal pathogens of ginseng, resulting in the suppression of root rot disease caused by C. destructans. Significance and Impact of the Study AK-0 is a potential source of novel bioactive metabolites. AK-0 CF exhibited antifungal effects against C. destructans on ginseng roots. PCR analysis indicated that the AK-0 harbours genes involved in the biosynthesis of antimicrobial compounds. [ABSTRACT FROM AUTHOR]

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Cylindrocarpon-like fungi are globally distributed plant pathogens and have a wide range of host species. However, very little is known about the species that live in the topsoil of forests and their potential role in reducing the natural regeneration of tree species, particularly of forest trees that produce abundant fruit only once every few years. To enhance our understanding of the species that inhabit the topsoil, we studied the diversity and pathogenicity of Cylindrocarpon-like fungi inhabiting the litter in old-growth mixed-beech forests in the Carpathians (Poland) and in the Alps (Austria), and in a managed beech stand in the Krakowsko-Częstochowska Highland (Poland). The fungi inhabiting the beech litter were investigated using beechnuts and pine seedlings as bait. Isolates were identified based on morphology and DNA sequencing. The pathogenicity of the most common species was investigated by inoculating beech germinants. A wide range of Cylindrocarpon-like fungi were associated with the beech litter: 718 cultures representing 12 species were isolated. Five taxa were identified down to species level: namely Ilyonectria crassa, I. pseudodestructans, I. rufa, Neonectria candida and N. obtusispora, and seven species were identified to genus level ( Neonectria or Ilyonectria species). Ilyonectria destructans, which is considered to be the sexual morph of ' Cylindrocarpon destructans', was not found. There were qualitative and quantitative differences between the different forest sites in terms of Neonectria and Ilyonectria species composition in beech litter. The isolation frequency and species richness of Cylindrocarpon-like fungi were greatest in beech litter taken from old-growth mixed-beech forests. Neonectria and Ilyonectria species were capable of killing beech germinants, suggesting that they may play a negative role in natural beech regeneration. [ABSTRACT FROM AUTHOR]

Fungi colonising oak seedlings in forest plantations in north-eastern Poland were identified in 2014-2015. The evaluated 4- to 6-year bare root oaks originated from the Olsztynek Forest District (Regional Directorate of the State Forests in Olsztyn). In total, 744 fungal isolates belonging to 11 different species, and 11 genera, were identified in tested plants. Amongst them, 186 cultures (25%) were classified as plant pathogens. The most commonly isolated pathogenic fungi belonged to the Fusarium and Cylindrocarpon genera. [ABSTRACT FROM AUTHOR]

Ginseng (Panax ginseng) is a traditional medicinal plant in China, and the dried root is highly valued for its medicinal properties and is widely used in Chinese traditional medicine. Cylindrocarpon root rot of ginseng caused by Cylindrocarpon destructans is the main disease, which is difficult to be eliminated from soil, leading to serious crop yield losses and limited the re-use of fields for successive ginseng crops. Methyl jasmonate (MeJA), which is one of the plant lipid derivatives, considered as a signaling substance during plant-microbe interactions. It is related to plant resistance to biotic and abiotic stress, can be involved in plant response to pathogens and other adversity stress and signal transmission, and can be used to induce plant disease resistance reaction. The objective of this study was to test the effects of MeJA on C. destructans and to find the possible relationships between MeJA and pathogenic factors of C. destructans. To assess the influence of MeJA on soil pathogens, the direct effects of artificially applied MeJA on C. destructans were evaluated, including the effects on colony growth, spore germination, biomass and phytopathogenic enzyme activities of this pathogen. The results showed that MeJA strongly inhibited its growth and spore germination, whereas it stimulated phytopathogenic enzyme activities. The colony diameter of C. destructans on PDA decreased from(8.23±0.15)cm(control)to(0.71±0.00)cm(800 μg · mL-1). At the highest concentration(800 μg · mL-1)of MeJA, the colony diameter of C. destructans had almost totally inhibited, but the diameter had no difference compared with the untreated control at lower concentrations(1-50 μg · mL-1 MeJA). The biomass reduced by 65.3%-100% and the percent of spore germination decreased by 100% at concentrations higher than 400 μg · mL-1. Potent suppression of the growth of germ-tubes was observed at different concentrations, especially at(400-800)μg · mL-1, where the growth of germ-tubes was inhibited completely. However, activities of phytopathogenic enzymes(pectinase, cellulase, amylase, and protease)were greatly stimulated by MeJA at higher concentrations(MeJA>200 μg · mL-1), while the activity of protease was little changed. The activity of pectinase was high up to(0.61±0.05)U·mL-1·min-1 at the concentration of 800 μg · mL-1. The activity of cellulase was stimulated at high concentrations of MeJA in liquid culture, while it was suppressed at low concentrations(1-50 μg · mL-1). The activity of cellulase was(0.31±0.02)μmol·min-1 at 800 μg · mL-1 of MeJA. Amylase activity substantial increased at concentrations of(200-800)μg · mL-1, which was(0.45±0.02)μmol·min-1 at the concentration of 800 μg · mL-1. It was concluded that MeJA greatly inhibited C. destructans growth and spore germination, but stimulated activities of hydrolytic enzymes of C. destructans at higher doses. There might be different mechanisms presented for the effects of MeJA on hyphal growth and virulence factors of C. destructans. The critical concentration of MeJA inhibitory effects on C. destructans was 200 μg · mL-1. The research lays a foundation for the subsequent experiment using MeJA to induct disease resistance. This is of help to understand the mechanism of Cylindrocarpon root rot of ginseng and to control pathogen in practice. [ABSTRACT FROM AUTHOR]

Cytochrome P450nor catalyzes an unusual reaction that transfers electrons from NADP/NADPH to bound heme directly. To improve the expression level of P450nor2 from Cylindrocarpon tonkinense (C.P450nor2), Escherichia coli system was utilized to substitute the yeast system we constructed for expression of the P450nor2 gene, and the protein was purified in soluble form using Ni-NTA affinity chromatography. In contrast to P450nor from Fusarium oxysporum (F.P450nor) and P450nor1 from Cylindrocarpon tonkinense (C.P450nor1), C.P450nor2 shows a dual specificity for using NADH or NADPH as electron donors. The present study developed a computational approach in order to illustrate the coenzyme specificity of C.P450nor2 for NADH and NADPH. This study involved homology modeling of C.P450nor2 and docking analyses of NADH and NADPH into the crystal structure of F.P450nor and the predictive model of C.P450nor2, respectively. The results suggested that C.P450nor2 and F.P450nor have different coenzyme specificity for NADH and NADPH; whilst the space around the B'-helix of the C.P450nor2, especially the Ser79 and Gly81, play a crucial role for the specificity of C.P450nor2. In the absence of the experimental structure of C.P450nor2, we hope that our model will be useful to provide rational explanation on coenzyme specificity of C.P450nor2. [ABSTRACT FROM AUTHOR]

Panax ginseng C. A. Meyer is a highly valued medicinal plant. Cylindrocarpon destructans is a destructive pathogen that causes root rot and significantly reduces the quality and yield of P. ginseng. However, an efficient method to control root rot remains unavailable because of insufficient understanding of the molecular mechanism underlying C. destructans-P. ginseng interaction. In this study, C. destructans-induced transcriptomes at different time points were investigated using RNA sequencing (RNA-Seq). De novo assembly produced 73,335 unigenes for the P. ginseng transcriptome after C. destructans infection, in which 3,839 unigenes were up-regulated. Notably, the abundance of the up-regulated unigenes sharply increased at 0.5 d postinoculation to provide effector-triggered immunity. In total, 24 of 26 randomly selected unigenes can be validated using quantitative reverse transcription (qRT)-PCR. Gene ontology enrichment analysis of these unigenes showed that “defense response to fungus”, “defense response” and “response to stress” were enriched. In addition, differentially expressed transcription factors involved in the hormone signaling pathways after C. destructans infection were identified. Finally, differentially expressed unigenes involved in reactive oxygen species and ginsenoside biosynthetic pathway during C. destructans infection were indentified. To our knowledge, this study is the first to report on the dynamic transcriptome triggered by C. destructans. These results improve our understanding of disease resistance in P. ginseng and provide a useful resource for quick detection of induced markers in P. ginseng before the comprehensive outbreak of this disease caused by C. destructans. [ABSTRACT FROM AUTHOR]

Genera with cylindrocarpon-like asexual morphs are important pathogens of various herbaceous and woody plant hosts globally. Recent multi-gene studies of this generic complex indicated that the genus Ilyonectria is paraphyletic. The present study was therefore initiated to re-evaluate the generic status of Ilyonectria and at the same time address some taxonomic irregularities in the genera Cylindrodendrum and Neonectria. Using multi-gene DNA data and morphological comparisons, the genus Dactylonectria is introduced with 10 new combinations, several of which were previously treated in Ilyonectria. Two new species, D. hordeicola and D. pinicola, are also described. Furthermore, one new combination is provided in the genus Cylindrodendrum, and three new combinations in the genus Neonectria, for species previously treated in the genera Acremonium, Cylindrocarpon, Nectria and Neonectria. The aquatic genus Heliscus is reduced to synonymy under Neonectria.

During the 2012 and 2013 growing seasons, a disease was detected on potted laurustinus (Viburnum tinus) plants in two nurseries located in the Catania province (eastern Sicily, Italy). 'Cylindrocarpon'-like species were consistently recovered from crown rot and stem rot tissues. Based on morphological characteristics, DNA sequencing and phylogenetic analysis of β-tubulin (TUB), histone H3 (HIS3) and translation elongation factor-1α (TEF-1 α) gene sequences, the fungi associated with symptomatic tissues were identified as 'Cylindrocarpon' pauciseptatum, Ilyonectria novozelandica and I. torresensis. Koch's postulates were fulfilled by pathogenicity tests carried out on potted V. tinus cuttings. To our knowledge, this is the first report worldwide of 'C.' pauciseptatum, I. novozelandica and I. torresensis causing disease on V. tinus. [ABSTRACT FROM AUTHOR]

This study aimed to elucidate the relationship between plant hosts and root-colonizing fungi recovered from apple orchard soils that had been replanted over multiple generations. Functional relationships of three groups of filamentous fungi ( Ceratobasidium sp., Cylindrocarpon-like group and Fusarium acuminatum) with apple rootstocks were evaluated in plant growth bioassays. The Cylindrocarpon-like group and Ceratobasidium sp. showed a relationship with the host plant varying from pathogenic to commensal through to mutualistic for the latter group, while that of F. acuminatum tended to be mutualistic. Seven fungal isolates of each group, which induced the highest plant growth in bioassays, were evaluated for auxin ( IAA) and gibberellin ( GA3 and GA4) production in culture filtrate. All isolates of F. acuminatum as well as most of those of the Ceratobasidium sp. and Cylindrocarpon-like groups produced IAA in culture filtrate. IAA production was evaluated for additional isolates of endophytic fungal species from fruit tree orchards and the functionality of IAA was confirmed by growing in vitro micropropagated plantlets of apple rootstock on MS medium supplemented with fungal culture filtrate. Findings from this study may explain the difficulty in defining the precise role of diverse root-colonizing fungal populations in replant disease aetiology of fruit tree orchards. However, the results demonstrate the presence of a positive and widely available biotic component of the orchard soil biology that may be exploited for the benefit of tree growth and production. [ABSTRACT FROM AUTHOR]

The broad biocontrol properties of myxobacteria (mainly members of the genera Corallococcus and Myxococcus) isolated from forest soils against main fungal pathogens of pine seedlings were estimated. Among the myxobacterial strains studied (in vivo tests), the strongest antagonism towards fungi was noticed for the strains of the species Myxococcus virescens Thaxter and Corallococcus exiguus Reichenbach. They inhibited the fungal growth within the range 38-63%. The strongest inhibitory reaction towards Cylindrocarpon destructans (Zinssm.) Scholten was observed. A predominating part of myxobacteria (22 from among 30) inhibited the growth of Rhizoctonia solani Kühn. Myxobacteria suppressed any pathogenic action of Rhizoctonia solani (strain 411) towards Scots pine seedlings (in vitro tests). They produced extracellular (but not intracellular) acidic and neutral proteinases. None of the myxobacterial strain under examination produced chitinases. The 57% of the myxobacterial strains studied produced siderophores. The numbers of myxobacterial strains, obtained from under forest trees were in the following order: Betula pendula Roth. > Pinus sylvestris L. > Alnus glutinosa Gaertn. = Quercus robur L. The results gained in present work have proved potential use of myxobacteria as biocontrol agents against Rhizoctonia solani, common fungal pathogen of pine seedlings. [ABSTRACT FROM AUTHOR]

Strain DCY85 and DCY85-1, isolated from rhizosphere of ginseng, were rod-shaped, Gram-reaction-negative, strictly aerobic, catalase positive and oxidase negative. 16S rRNA gene sequence analysis revealed that strain DCY85 as well as DCY85-1 belonged to the genus Burkholderia and were closely related to Burkholderia fungorum KACC 12023 (98.1 and 98.0 % similarity, respectively). The major polar lipids of strain DCY85 and DCY85-1 were phosphatidylethanolamine, one unidentified aminolipid and two unidentified phospholipids. The major fatty acids of both strains are C, C ω7c and summed feature 3 (C ω6c and/or C ω7c). The predominant isoprenoid quinone of each strain DCY85 and DCY85-1 was ubiquinone (Q-8) and the G+C content of their genomic DNA was 66.0 and 59.4 mol%, respectively, which fulfill the characteristic range of the genus Burkholderia. The polyamine content of both DCY85 and DCY85-1 was putrescine. Although both DCY85 and DCY85-1 have highly similar 16S rRNA and identical RecA and gyrB sequences, they show differences in phenotypic and chemotaxonomic characteristics. DNA-DNA hybridization results proved the consideration of both strains as two different species. Based on the results from our polyphasic characterization, strain DCY85 and DCY85-1 are considered novel Burkholderia species for which the name Burkholderia ginsengiterrae sp. nov and Burkholderia panaciterrae sp. nov are, respectively, proposed. An emended description of those strains is also proposed. DCY85 and DCY85-1 showed antagonistic activity against the common root rot pathogen of ginseng, Cylindrocarpon destructans. The proposed type strains are DCY85 (KCTC 42054 = JCM 19888) and DCY85-1 (KCTC 42055 = JCM 19889). [ABSTRACT FROM AUTHOR]

Genera with cylindrocarpon-like asexual morphs are important pathogens of various herbaceous and woody plant hosts globally. Recent multi-gene studies of this generic complex indicated that the genus Ilyonectria is paraphyletic. The present study was therefore initiated to re-evaluate the generic status of Ilyonectria and at the same time address some taxonomic irregularities in the genera Cylindrodendrum and Neonectria. Using multi-gene DNA data and morphological comparisons, the genus Dactylonectria is introduced with 10 new combinations, several of which were previously treated in Ilyonectria. Two new species, D. hordeicola and D. pinicola, are also described. Furthermore, one new combination is provided in the genus Cylindrodendrum, and three new combinations in the genus Neonectria, for species previously treated in the genera Acremonium, Cylindrocarpon, Nectria and Neonectria. The aquatic genus Heliscus is reduced to synonymy under Neonectria. [ABSTRACT FROM AUTHOR]

In this study, aquatic and aerial algae were collected in various environments in Hongcheon-river of Gangwan-do between December 2011 and June 2012, with the aim of adding newly described genera and species to the Korean flora. As a result, five genera and eight species were recorded for the first time in Korea. These newly recorded genera and species were Cylindrocapsa geminella, Leptosira mediciana, Pseudendoclonium basiliense var. brandii, Stichococcus minor, S. deasonii, Eustigmatos polyphem, Nephrodiella lunaris, and Xanthonema exile. The eight taxa identified in this study mostly corresponded to their reported morphological characteristics. However, some differences from previous published descriptions were found; N. lunaria, reported to be an aquatic species in a previous study, was found to be an aerial algae inhabiting on rocks and mosses. Cylindrocapsa geminella was found to transform into attached or planktonic algae depending on the environmental condition, and the cell wall was found to be changed. Likewise, E. polyphem was seen to change cell-shape or chloroplast color according to the environment. [ABSTRACT FROM AUTHOR]

The primary symptoms associated withFusarium circinatuminfection in pine seedling nurseries are root and collar rot, shoot and tip die-back and seedling mortality. Management of this pathogen in nurseries usually involves the integration of various strategies relating to sanitation, insect control and fungicide treatment. The overall goal of this study was to use quantitative real-time PCR (qPCR) to detect and quantify the airborne inoculum ofF. circinatumin a commercial pine seedling nursery. For this purpose, an existing qPCR method was optimised and evaluated for its efficacy to quantify and monitor airborne conidia over a one-year period. Results showed thatF. circinatumoccurred at relatively low levels in the nursery throughout the year and that its distribution was spatially sporadic. The data suggest that standard nursery sanitation practices in the test nursery maintained the airborne inoculum ofF. circinatumat low levels. The uneven distribution of infection also suggests that airborne inoculum does not represent the primary source of inoculum for theF. circinatum-associated seedling disease. [ABSTRACT FROM AUTHOR]

We analyzed the genetic diversity of Cylindrocarpon destructans isolates obtained from Korean ginseng (i.e., Panax ginseng) roots by performing virulence tests and nuclear ribosomal gene internal transcribed spacer (ITS) and mitochondrial small subunit (mt SSU) rDNA sequence analysis. The phylogenetic relationship analysis performed using ITS DNA sequences and isolates from other hosts helped confirm that all the Korean C. destructans isolates belonged to Nectria/Neonectria radicicola complex. The results of in vivo and ex vivo virulence tests showed that the C. destructans isolates could be divided into two groups according to their distinctive difference in virulence and the genetic diversity. The highly virulent Korean isolates in pathogenicity group II (PC II), together with foreign isolates from P ginseng and R quinquefolius, formed a single group. The weakly virulent isolates in pathogenicity group I, together with the foreign isolates from other host plants, formed another group and exhibited a greater genetic diversity than the isolates of PC II, as confirmed by the mt SSU rDNA sequence analysis. In addition, as the weakly virulent Korean isolates were genetically very similar to the foreign isolates from other hosts, they were likely to originate from hosts other than the ginseng plants. [ABSTRACT FROM AUTHOR]

Understanding the interactions of plant-parasitic nematodes with antagonistic soil microbes could provide opportunities for novel crop protection strategies. Three arable soils were investigated for their suppressiveness against the root knot nematode Meloidogyne hapla. For all three soils, M. hapla developed significantly fewer galls, egg masses, and eggs on tomato plants in unsterilized than in sterilized infested soil. Egg numbers were reduced by up to 93%. This suggested suppression by soil microbial communities. The soils significantly differed in the composition of microbial communities and in the suppressiveness to M. hapla. To identify microorganisms interacting with M. hapla in soil, second-stage juveniles (J2) baited in the test soil were cultivation independently analyzed for attached microbes. PCR-denaturing gradient gel electrophoresis of fungal ITS or 16S rRNA genes of bacteria and bacterial groups from nematode and soil samples was performed, and DNA sequences from 12-associated bands were determined. The fingerprints showed many species that were abundant on J2 but not in the surrounding soil, especially in fungal profiles. Fungi associated with 12 from all three soils were related to the genera Davidiella and Rhizophydium, while the genera Eurotium, Ganoderma, and Cylindrocarpon were specific for the most suppressive soil. Among the 20 highly abundant operational taxonomic units of bacteria specific for 12 in suppressive soil, six were closely related to infectious species such as Shigella spp., whereas the most abundant were Malikia spinosa and Rothia amarae, as determined by 16S rRNA amplicon pyrosequencing. In conclusion, a diverse microflora specifically adhered to 12 of M. hapla in soil and presumably affected female fecundity. [ABSTRACT FROM AUTHOR]

Black foot disease of grapevines, caused by several fungal species in the genera Campylocarpon, Cylindrocarpon, Cylindrocladiella, and Ilyonectria, causes significant economic losses to the grapevine indus-try worldwide. This study represents the first attempt to identify and characterize the fungal pathogens associated with black foot disease of grapevines in British Columbia (BC). Field surveys conducted throughout all grape-growing regions in BC that included assessment of foliar symptomatology and isolations from symptomatic vines showed Cylindrocarpon/Ilyonectria spp. occurred in 32 of 90 (35.5%) young vineyards surveyed (<8 year old) and in 41 of 215 (19%) sam-ples collected. In 20 of the 41 (48.8%) samples, Cylindrocarpon/ Ilyonectria spp. were the sole fungi isolated from symptomatic tissue. In the rest of the samples, black foot fungi were found to primarily coexist with fungal taxa associated with Petri disease of grapevines. Colony and conidia phenotypical characterization, along with DNA analyses of the internal transcribed spacer region (ITS1-5.8S-ITS2) of the rDNA, and part of the ß-tubulin and translation elongation factor 1-a genes, revealed five different black foot fungi occurring in declining young vines in BC, namely Cylindrocarpon pauciseptatum, Ilyonectria liriodendri, Ilyonectria macrodidyma, Ilyonectria robusta, and Ilyonec-tria torresensis. Pathogenicity studies showed all five species to be highly virulent in the grapevine rootstock cultivar 3309C. Overall, 1. liriodendri and I. macrodidyma were the most virulent species when inoculated in Vitis vinifera 'Chardonnay' and rootstock 3309C. [ABSTRACT FROM AUTHOR]

The ornamental Tagetes minuta is a herbaceous plant of the Asteraceae family. T. minuta, a species native to southern South America, is used as a condiment, as a refreshing beverage, and for medicinal purposes. In 2011, disease symptoms of yellowing, root and foot rot, drying of leaves, and plant death were observed in an ornamental marigold (T. minuta) greenhouse in Fars province. The infected plants were collected and transferred to a laboratory. Samples were washed, cut into small pieces, surface disinfested with a 0.5% NaClO solution, and cultured on Potato Dextrose Agar (PDA) acidified to pH 4.5 with 0.5% lactic acid. Based on morphological characters, the causal agent was identified as Cylindrocarpon destructans. To confirm morphological identification, DNA was extracted from isolates using a genomic DNA purification Kit. The region of internal transcribed spacers 1, 2, and 5.8S genes of rDNA were amplified using the ITS4 and ITS1 universal primer set. Fragments of 600 bp were recovered from PCR, purified, sequenced, edited, and deposited in GenBank. The isolates had a 100% identity with all the compared C. destructans sequences. The pathogenicity tests were done with a suspension of 1 x 106 conidia per ml homogenised in sterile water. The symptoms on inoculated plants were similar to those previously observed and the fungus was reisolated from the inoculated plants. This is the first documented report of C. destructans as a cause of root and foot rot disease on T. minuta in Iran. [ABSTRACT FROM AUTHOR]