Phyllosticta capitalensis is an endophyte and weak plant pathogen with a worldwide distribution presently known from 70 plant families.This study isolated P.capitalensis from different host plants in northern Thailand...Phyllosticta capitalensis is an endophyte and weak plant pathogen with a worldwide distribution presently known from 70 plant families.This study isolated P.capitalensis from different host plants in northern Thailand,and determined their different life modes.Thirty strains of P.capitalensis were isolated as endophytes from 20 hosts.An additional 30 strains of P.capitalensis from other hosts and geographic locations were also obtained from established culture collections.Phylogenetic analysis using ITS,ACTand TEF gene data confirmed the identity of all isolates.Pathogenicity tests with five strains of P.capitalensis originating from different hosts were completed on their respective host plants.In all cases there was no infection of healthy leaves,indicating that this endophyte does not cause disease on healthy,unstressed host plants.That P.capitalensis is often isolated as an endophyte has important implications in fungal biology and plant health.Due to its endophytic nature,P.capitalensisis commonly found associated with lesions of plants,and often incorrectly identified as a species of quarantine importance,which again has implications for trade in agricultural and forestry production.展开更多
Plant pathogenic fungi are a large and diverse assemblage of eukaryotes with substantial impacts on natural ecosystems and human endeavours.These taxa often have complex and poorly understood life cycles,lack observab...Plant pathogenic fungi are a large and diverse assemblage of eukaryotes with substantial impacts on natural ecosystems and human endeavours.These taxa often have complex and poorly understood life cycles,lack observable,discriminatory morphological characters,and may not be amenable to in vitro culturing.As a result,species identification is frequently difficult.Molecular(DNA sequence)data have emerged as crucial information for the taxonomic identification of plant pathogenic fungi,with the nuclear ribosomal internal transcribed spacer(ITS)region being the most popular marker.However,international nucleotide sequence databases are accumulating numerous sequences of compromised or low-resolution taxonomic annotations and substandard technical quality,making their use in the molecular identification of plant pathogenic fungi problematic.Here we report on a concerted effort to identify high-quality reference sequences for various plant pathogenic fungi and to re-annotate incorrectly or insufficiently annotated public ITS sequences from these fungal lineages.A third objective was to enrich the sequences with geographical and ecological metadata.The results-a total of 31,954 changes-are incorporated in and made available through the UNITE database for molecular identification of fungi(http://unite.ut.ee),including standalone FASTA files of sequence data for local BLAST searches,use in the next-generation sequencing analysis platforms QIIME and mothur,and related applications.The present initiative is just a beginning to cover the wide spectrum of plant pathogenic fungi,and we invite all researchers with pertinent expertise to join the annotation effort.展开更多
This study aims to report baseline soil nutrients, specifically the organic carbon, nitrogen and phosphorus profile, in soil samples collected from Puntta Fort William on Greenwich Island in maritime Antarctic. Sample...This study aims to report baseline soil nutrients, specifically the organic carbon, nitrogen and phosphorus profile, in soil samples collected from Puntta Fort William on Greenwich Island in maritime Antarctic. Samples were collected along two transect lines during the early summer of 2008. Ward＇s method of hierarchical agglomerative clustering was employed to group the sampling points based on their physico-chemical properties. In this context, the soil samples can be grouped into three major clus- ters： （1） Samples with intensive biological activities, （2） samples from the area recently exposed by glacial retreat and （3） samples from barren and dried areas. Nutrient contents in Punta Fort William are driven by the intensity of biological activities as well as melt water from the Qnito glacier.展开更多
Various crude extracts of Lentinus squarrosulus mushroom mycelium and culture broth were prepared for antioxidant studies, glucan and carbohydrate compound analysis. Crude extract from ethanol, cold and hot water extr...Various crude extracts of Lentinus squarrosulus mushroom mycelium and culture broth were prepared for antioxidant studies, glucan and carbohydrate compound analysis. Crude extract from ethanol, cold and hot water extraction was tested on several complementary test systems namely DPPH free radical scavenging, β-carotene linoleic acid oxidation, total phenolic compound, total flavonoid compound, total carbohydrate content and total glucan compositions. The antioxidant activity of the crude extracts of Lentinus squarrosulus mushroom mycelium and culture broth was determined by 2,2’ diphenyl-1-picrylhydrazyl (DPPH) radical scavenging method and β-carotene linoleic acid assay. Crude extracted from culture broth EPS EE recorded the highest radical scavenging effects at 20 mg/mL (85%) which is closer to the control antioxidants (ascorbic acid 97%;BHT 92.4%;BHA 93.6%). Both the ethanol extract (IPS EE and EPS EE) exhibited the highest β-carotene linoleic acid oxidation by recording IC50 values of 0.6 and 0.65 mg/mL respectively. IPS EE (0.59 mg/g) and EPS WE (0.58 mg/g) showed high flavonoid content whereas total phenol content was high in EPS WE (0.85 mg/g) and IPS EE (0.84 mg/g). Total carbohydrate concentrations were high in IPS HWE and IPS CWE with 19.1 and 16.3 mg/mL respectively and these data correlate with the β-glucan content in both extracts. The highest β-glucan content found in IPS CWE and IPS HWE were 12.2 and 11.4% w/w respectively.展开更多
基金supported by the Thailand Research Fund through the Royal Golden Jubilee Ph.D.Program(Grant No.PHD/0198/2552)to S.Wikee and Kevin D.Hyde.
文摘Phyllosticta capitalensis is an endophyte and weak plant pathogen with a worldwide distribution presently known from 70 plant families.This study isolated P.capitalensis from different host plants in northern Thailand,and determined their different life modes.Thirty strains of P.capitalensis were isolated as endophytes from 20 hosts.An additional 30 strains of P.capitalensis from other hosts and geographic locations were also obtained from established culture collections.Phylogenetic analysis using ITS,ACTand TEF gene data confirmed the identity of all isolates.Pathogenicity tests with five strains of P.capitalensis originating from different hosts were completed on their respective host plants.In all cases there was no infection of healthy leaves,indicating that this endophyte does not cause disease on healthy,unstressed host plants.That P.capitalensis is often isolated as an endophyte has important implications in fungal biology and plant health.Due to its endophytic nature,P.capitalensisis commonly found associated with lesions of plants,and often incorrectly identified as a species of quarantine importance,which again has implications for trade in agricultural and forestry production.
基金financial support from European Funds through COMPETENational Funds through the Portuguese Foundation for Science and Technology(FCT)within projects PTDC/AGR-FOR/3807/2012-FCOMP-01-0124-FEDER-027979 and PEst-C/MAR/LA0017/2013+4 种基金supported by National Science Foundation Grant DBI 1046115supported by FFG,BMWFJ,BMVIT,ZIT,Zukunftsstiftung Tirol,and Land Steiermark within the Austrian COMET program FFG Grant 824186Financial support to JP was partially provided by the Polish Ministry of Science and Higher Education(MNiSW),grant no.NN303_548839financial support from FAPEMIG and CNPqfunded by the Government of Canada through Genome Canada and the Ontario Genomics Institute through the Biomonitoring 2.0 project(OGI-050).
文摘Plant pathogenic fungi are a large and diverse assemblage of eukaryotes with substantial impacts on natural ecosystems and human endeavours.These taxa often have complex and poorly understood life cycles,lack observable,discriminatory morphological characters,and may not be amenable to in vitro culturing.As a result,species identification is frequently difficult.Molecular(DNA sequence)data have emerged as crucial information for the taxonomic identification of plant pathogenic fungi,with the nuclear ribosomal internal transcribed spacer(ITS)region being the most popular marker.However,international nucleotide sequence databases are accumulating numerous sequences of compromised or low-resolution taxonomic annotations and substandard technical quality,making their use in the molecular identification of plant pathogenic fungi problematic.Here we report on a concerted effort to identify high-quality reference sequences for various plant pathogenic fungi and to re-annotate incorrectly or insufficiently annotated public ITS sequences from these fungal lineages.A third objective was to enrich the sequences with geographical and ecological metadata.The results-a total of 31,954 changes-are incorporated in and made available through the UNITE database for molecular identification of fungi(http://unite.ut.ee),including standalone FASTA files of sequence data for local BLAST searches,use in the next-generation sequencing analysis platforms QIIME and mothur,and related applications.The present initiative is just a beginning to cover the wide spectrum of plant pathogenic fungi,and we invite all researchers with pertinent expertise to join the annotation effort.
基金the Malaysian Antarctic Research Program(MARP)Ministry of Higher Education(MoHE),MalaysiaInstituto Antartico Ecuatoriano(INAE)for sponsoring the study
文摘This study aims to report baseline soil nutrients, specifically the organic carbon, nitrogen and phosphorus profile, in soil samples collected from Puntta Fort William on Greenwich Island in maritime Antarctic. Samples were collected along two transect lines during the early summer of 2008. Ward＇s method of hierarchical agglomerative clustering was employed to group the sampling points based on their physico-chemical properties. In this context, the soil samples can be grouped into three major clus- ters： （1） Samples with intensive biological activities, （2） samples from the area recently exposed by glacial retreat and （3） samples from barren and dried areas. Nutrient contents in Punta Fort William are driven by the intensity of biological activities as well as melt water from the Qnito glacier.
文摘Various crude extracts of Lentinus squarrosulus mushroom mycelium and culture broth were prepared for antioxidant studies, glucan and carbohydrate compound analysis. Crude extract from ethanol, cold and hot water extraction was tested on several complementary test systems namely DPPH free radical scavenging, β-carotene linoleic acid oxidation, total phenolic compound, total flavonoid compound, total carbohydrate content and total glucan compositions. The antioxidant activity of the crude extracts of Lentinus squarrosulus mushroom mycelium and culture broth was determined by 2,2’ diphenyl-1-picrylhydrazyl (DPPH) radical scavenging method and β-carotene linoleic acid assay. Crude extracted from culture broth EPS EE recorded the highest radical scavenging effects at 20 mg/mL (85%) which is closer to the control antioxidants (ascorbic acid 97%;BHT 92.4%;BHA 93.6%). Both the ethanol extract (IPS EE and EPS EE) exhibited the highest β-carotene linoleic acid oxidation by recording IC50 values of 0.6 and 0.65 mg/mL respectively. IPS EE (0.59 mg/g) and EPS WE (0.58 mg/g) showed high flavonoid content whereas total phenol content was high in EPS WE (0.85 mg/g) and IPS EE (0.84 mg/g). Total carbohydrate concentrations were high in IPS HWE and IPS CWE with 19.1 and 16.3 mg/mL respectively and these data correlate with the β-glucan content in both extracts. The highest β-glucan content found in IPS CWE and IPS HWE were 12.2 and 11.4% w/w respectively.
