Endophytic fungi are widely found in almost all kinds of plants. Many endophytic fungi can produce some physio-logical active compounds, which are same to or analog to those isolated from their hosts. Producing physio...Endophytic fungi are widely found in almost all kinds of plants. Many endophytic fungi can produce some physio-logical active compounds, which are same to or analog to those isolated from their hosts. Producing physiological active com-pounds through microbial fermentation can give a new way to resolve resource limitation and to find out alternative source. Through the methods of organic solvent extraction, thin layer chromatography (TLC) and column chromatography, compound I was isolated, purified from the liquid fermentation metabolites of the taxoids-produced endophytic fungi (Alternaria. alternata var. taxi 1011 Y. Xiang et LU An-guo) that was screened from the bark of Taxus. cuspidata Sieb.et Zucc.. Compound I was identified as one kind of taxoids type III, based on the analyzing results by using the methods of ultraviolet spectroscopy (UV), infrared spectroscopy (IR), mass spectrometry (MS) and nuclear magnetic resonance spectroscopy (NMR). This study provides a com-pleted method for separation and purification of the endophytic fungi as well as structure identification of its fermentation me-tabolite展开更多
Apple leaf spot,caused by the Alternaria alternata apple pathotype(AAAP),is an important fungal disease of apple.To understand the molecular basis of resistance and pathogenesis in apple leaf spot,the transcriptomes o...Apple leaf spot,caused by the Alternaria alternata apple pathotype(AAAP),is an important fungal disease of apple.To understand the molecular basis of resistance and pathogenesis in apple leaf spot,the transcriptomes of two apple cultivars‘Hanfu'(HF)(resistant)and‘Golden Delicious'(GD)(susceptible)were analyzed at 0,6,18,24 and 48 h after AAAP inoculation by RNA-Seq.At each time point,a large number of significantly differentially expressed genes(DEGs)were screened between AAAP-inoculated and uninoculated apple leaves.Analysis of the common DEGs at four time points revealed significant differences in the resistance of‘HF'and‘GD'apple to AAAP infection.RLP,RNL,and JA signal-related genes were upregulated in both cultivars to restrict AAAP development.However,genes encoding CNLs,TNLs,WRKYs,and AP2s were only activated in‘HF'as part of the resistance response,of which,some play major roles in the regulation of ET and SA signal transduction.Further analysis showed that many DEGs with opposite expression trends in the two hosts may play important regulatory roles in response to AAAP infection.Transient expression of one such gene MdERF110 in‘GD'apple leaves improved AAAP resistance.Collectively,this study highlights the reasons for differential resistance to AAAP infection between‘HF'and‘GD'apples which can theoretically assist the molecular breeding of disease-resistant apple crops.展开更多
In this research,green synthesized magnesium oxide nanoparticles(MgO NPs)from lemon fruit extracts and their fungicidal potential was evaluated against Alternaria dauci infection on carrot(Daucus carota L.)under green...In this research,green synthesized magnesium oxide nanoparticles(MgO NPs)from lemon fruit extracts and their fungicidal potential was evaluated against Alternaria dauci infection on carrot(Daucus carota L.)under greenhouse conditions.The scanning and transmission electron microscopy(SEM and TEM)and ultra-violet(UV)visible spectroscopy were used to validate and characterize MgO NPs.The crystalline nature of MgONPs was determined using selected area electron diffraction(SAED).MgO NPs triggered substantial antifungal activity against A.dauci when exposed to 50 and 100 mg L^(–1)concentrations but the higher antifungal potential was noticed in 100 mg L^(–1)under invitro conditions.In fungal inoculated plants,a marked decrease in growth,photosynthetic pigments,and an increase in phenol,proline contents,and defense-related enzymes of carrot were seen over control(distilled water).However,foliar application of MgO NPs at 50 and 100 mg L^(–1)resulted in significant improvement of plant growth,photosynthetic pigments,phenol and proline contents,and defense enzymes activity of carrots with and without A.dauci infection.Spraying of MgO NPs at 100 mg L^(–1)had more plant length(17.11%),shoot dry weight(34.38%),plant fresh weight(20.46%),and root dry weight(49.09%)in carrots when challenged with A.dauci over inoculated control.The leaf blight indices and percent disease severity were also reduced in A.dauci inoculated plants when sprayed with MgO NPs.The non-bonding interactions of Alternaria genus protein with nanoparticles were studied using molecular docking.展开更多
Three new amide derivatives(alteralkaloids A-C,1-3)and three known alkaloids(4-6)were afforded after phytochemical investigation of fungus Alternaria brassicicola.The structures of these compounds were confirmed by NM...Three new amide derivatives(alteralkaloids A-C,1-3)and three known alkaloids(4-6)were afforded after phytochemical investigation of fungus Alternaria brassicicola.The structures of these compounds were confirmed by NMR spectroscopic and HRESIMS data.Furthermore,the absolute configuration of 1 was determined using the single-crystal X-ray diffraction analysis.Compounds 1-3 belong to a class of amide derivatives that have not been found in nature before,sharing the same characteristic signals of the butyl moiety and amide group.These isolated compounds mentioned above were tested for the cytotoxic activity.展开更多
[Objectives]The paper was to identify Alternaria alternata causing leaf spot disease on Huangdi banana in China.[Methods]Fungal isolates were isolated and identified by morphological features,molecular identification ...[Objectives]The paper was to identify Alternaria alternata causing leaf spot disease on Huangdi banana in China.[Methods]Fungal isolates were isolated and identified by morphological features,molecular identification and pathogenicity test.[Results]There were light to dark brown,tiny oval spots on leaves.The causal agent isolated from affected leaves was identified as A.alternata based on the morphological properties,coupled with sequence analyses of the internal transcribed spacer(ITS)region,large subunit ribosomal DNA(LSU rDNA)and the translation elongation factor 1-alpha(TEF-1α)gene.Koch s postulates were fulfilled by successful re-isolation of pathogen from the artificial inoculated leaves.[Conclusions]To our knowledge,this is the first report of leaf spot caused by A.alternata on Huangdi banana in China.The identification of A.alternata as the causal agent of the observed leaf spot disease on Huangdi banana is critical to the prevention and control of this disease in the future.展开更多
Centella asiatica (L.), frequently known as Thankuni, is an important ethnobotanical plant in Bangladesh. This study was conducted to evaluate the morphological characteristics, cultural factors and molecular identifi...Centella asiatica (L.), frequently known as Thankuni, is an important ethnobotanical plant in Bangladesh. This study was conducted to evaluate the morphological characteristics, cultural factors and molecular identification of the causal agent of Alternaria leaf blight disease of C. asiatica. The potato dextrose agar (PDA) medium recorded the maximum mycelial growth (69 mm), followed by the yeast extract agar (YEA) medium, while the honey peptone agar (HPA) medium recorded the lowest growth (27 mm). The optimal pH and temperature for mycelial growth of Alternaria alternata were 6 and 30°C, respectively. Internal transcribed spacer (ITS) region of Alternaria alternata PCR products measured 558 bp and blast search showed 99% sequence similarity with Alternaria alternata species complex. To the best of our knowledge, Alternaria leaf blight disease caused by Alternaria alternata is the first record in Bangladesh.展开更多
文摘Endophytic fungi are widely found in almost all kinds of plants. Many endophytic fungi can produce some physio-logical active compounds, which are same to or analog to those isolated from their hosts. Producing physiological active com-pounds through microbial fermentation can give a new way to resolve resource limitation and to find out alternative source. Through the methods of organic solvent extraction, thin layer chromatography (TLC) and column chromatography, compound I was isolated, purified from the liquid fermentation metabolites of the taxoids-produced endophytic fungi (Alternaria. alternata var. taxi 1011 Y. Xiang et LU An-guo) that was screened from the bark of Taxus. cuspidata Sieb.et Zucc.. Compound I was identified as one kind of taxoids type III, based on the analyzing results by using the methods of ultraviolet spectroscopy (UV), infrared spectroscopy (IR), mass spectrometry (MS) and nuclear magnetic resonance spectroscopy (NMR). This study provides a com-pleted method for separation and purification of the endophytic fungi as well as structure identification of its fermentation me-tabolite
基金financially supported by the National Natural Science Foundation of China(Grant No.32202463)China Agriculture Research System(Grant No.CARS-27)the Agricultural Science and Technology Innovation Program(Grant No.CAAS-ASTIP-2021-RIP-02)。
文摘Apple leaf spot,caused by the Alternaria alternata apple pathotype(AAAP),is an important fungal disease of apple.To understand the molecular basis of resistance and pathogenesis in apple leaf spot,the transcriptomes of two apple cultivars‘Hanfu'(HF)(resistant)and‘Golden Delicious'(GD)(susceptible)were analyzed at 0,6,18,24 and 48 h after AAAP inoculation by RNA-Seq.At each time point,a large number of significantly differentially expressed genes(DEGs)were screened between AAAP-inoculated and uninoculated apple leaves.Analysis of the common DEGs at four time points revealed significant differences in the resistance of‘HF'and‘GD'apple to AAAP infection.RLP,RNL,and JA signal-related genes were upregulated in both cultivars to restrict AAAP development.However,genes encoding CNLs,TNLs,WRKYs,and AP2s were only activated in‘HF'as part of the resistance response,of which,some play major roles in the regulation of ET and SA signal transduction.Further analysis showed that many DEGs with opposite expression trends in the two hosts may play important regulatory roles in response to AAAP infection.Transient expression of one such gene MdERF110 in‘GD'apple leaves improved AAAP resistance.Collectively,this study highlights the reasons for differential resistance to AAAP infection between‘HF'and‘GD'apples which can theoretically assist the molecular breeding of disease-resistant apple crops.
基金the Researchers Supporting Project Number(RSP2023R339)at King Saud University,Riyadh,Saudi Arabia。
文摘In this research,green synthesized magnesium oxide nanoparticles(MgO NPs)from lemon fruit extracts and their fungicidal potential was evaluated against Alternaria dauci infection on carrot(Daucus carota L.)under greenhouse conditions.The scanning and transmission electron microscopy(SEM and TEM)and ultra-violet(UV)visible spectroscopy were used to validate and characterize MgO NPs.The crystalline nature of MgONPs was determined using selected area electron diffraction(SAED).MgO NPs triggered substantial antifungal activity against A.dauci when exposed to 50 and 100 mg L^(–1)concentrations but the higher antifungal potential was noticed in 100 mg L^(–1)under invitro conditions.In fungal inoculated plants,a marked decrease in growth,photosynthetic pigments,and an increase in phenol,proline contents,and defense-related enzymes of carrot were seen over control(distilled water).However,foliar application of MgO NPs at 50 and 100 mg L^(–1)resulted in significant improvement of plant growth,photosynthetic pigments,phenol and proline contents,and defense enzymes activity of carrots with and without A.dauci infection.Spraying of MgO NPs at 100 mg L^(–1)had more plant length(17.11%),shoot dry weight(34.38%),plant fresh weight(20.46%),and root dry weight(49.09%)in carrots when challenged with A.dauci over inoculated control.The leaf blight indices and percent disease severity were also reduced in A.dauci inoculated plants when sprayed with MgO NPs.The non-bonding interactions of Alternaria genus protein with nanoparticles were studied using molecular docking.
基金the National Program for Support of Top-notch Young Professionals(No.0106514050)the National NSFC(Nos.82273811 and 82104043)+3 种基金the National Key R&D Program of China(No.2021YFA0910500)the National NSF for Distinguished Young Scholars(No.81725021)the Innovative Research Groups of the National NSFC(No.81721005)the Academic Frontier Youth Team of HUST(No.2017QYTD19).
文摘Three new amide derivatives(alteralkaloids A-C,1-3)and three known alkaloids(4-6)were afforded after phytochemical investigation of fungus Alternaria brassicicola.The structures of these compounds were confirmed by NMR spectroscopic and HRESIMS data.Furthermore,the absolute configuration of 1 was determined using the single-crystal X-ray diffraction analysis.Compounds 1-3 belong to a class of amide derivatives that have not been found in nature before,sharing the same characteristic signals of the butyl moiety and amide group.These isolated compounds mentioned above were tested for the cytotoxic activity.
基金Supported by China Agriculture Research System(CARS-31).
文摘[Objectives]The paper was to identify Alternaria alternata causing leaf spot disease on Huangdi banana in China.[Methods]Fungal isolates were isolated and identified by morphological features,molecular identification and pathogenicity test.[Results]There were light to dark brown,tiny oval spots on leaves.The causal agent isolated from affected leaves was identified as A.alternata based on the morphological properties,coupled with sequence analyses of the internal transcribed spacer(ITS)region,large subunit ribosomal DNA(LSU rDNA)and the translation elongation factor 1-alpha(TEF-1α)gene.Koch s postulates were fulfilled by successful re-isolation of pathogen from the artificial inoculated leaves.[Conclusions]To our knowledge,this is the first report of leaf spot caused by A.alternata on Huangdi banana in China.The identification of A.alternata as the causal agent of the observed leaf spot disease on Huangdi banana is critical to the prevention and control of this disease in the future.
文摘Centella asiatica (L.), frequently known as Thankuni, is an important ethnobotanical plant in Bangladesh. This study was conducted to evaluate the morphological characteristics, cultural factors and molecular identification of the causal agent of Alternaria leaf blight disease of C. asiatica. The potato dextrose agar (PDA) medium recorded the maximum mycelial growth (69 mm), followed by the yeast extract agar (YEA) medium, while the honey peptone agar (HPA) medium recorded the lowest growth (27 mm). The optimal pH and temperature for mycelial growth of Alternaria alternata were 6 and 30°C, respectively. Internal transcribed spacer (ITS) region of Alternaria alternata PCR products measured 558 bp and blast search showed 99% sequence similarity with Alternaria alternata species complex. To the best of our knowledge, Alternaria leaf blight disease caused by Alternaria alternata is the first record in Bangladesh.
