Root-associated endophytic fungi like Serendipita indica and arbuscular mycorrhizal(AM) fungi can improve plant growth and root construction, but the potential mechanism is unclear. In this study, Funneliformis mossea...Root-associated endophytic fungi like Serendipita indica and arbuscular mycorrhizal(AM) fungi can improve plant growth and root construction, but the potential mechanism is unclear. In this study, Funneliformis mosseae(an AM fungus) and S. indica, singly or in combination were inoculated into trifoliate orange(Poncirus trifoliata) seedlings, to assess changes in biomass and root morphological traits, coupled with auxins and cytokinins concentrations in leaves and roots and the expression of auxin synthesis and transporter protein genes. After 20 weeks of inoculation with these fungi, shoot and root biomass, root total length, taproot length, average diameter, surface area, volume, and the number of lateral roots in 1st-, 2nd-, and 3rd-order were improved, and S. indica showed a relatively greater effect than F. mosseae and dual inoculation. Endophytic fungal inoculation also significantly increased the concentration of indoleacetic acid, indole butyric acid, trans-zeatin,dihydrozeatin, and isopentenyl adenine in leaves and roots, whilst F. mosseae and S. indica exhibited relatively greater effects on leaves and roots, respectively. Correlation analysis revealed that both biomass and root morphological traits(except root projected area) were significantly positively associated with endogenous auxins and cytokinins. In addition, the inoculated plants recorded comparatively higher expression levels of indoleacetic acid synthesis genes(PtTAA1, PtTAR2, PtYUC3, PtYUC4, PtYUC6, and PtYUC8) and indoleacetic acid transporter protein genes(PtAUX1, PtLAX1, PtLAX2, PtLAX3, PtPIN1, PtPIN3, PtPIN4, PtABCB1, and PtABCB19) than the non-inoculated plants, among which F. mosseae and S. indica showed better effects in leaves and roots, respectively. These results suggest that root-associated endophytic fungi improved plant growth and root architecture, which were associated with changes in endogenous auxins and cytokinins.展开更多
Melatonin and dopamine can potentially prevent waterlogging stress in apples.The current study investigated the mechanism by which melatonin and dopamine alleviate apple waterlogging stress.This study demonstrated tha...Melatonin and dopamine can potentially prevent waterlogging stress in apples.The current study investigated the mechanism by which melatonin and dopamine alleviate apple waterlogging stress.This study demonstrated that melatonin and dopamine alleviated waterlogging by removing reactive oxygen species(ROS),and that the nitric oxide(NO)content and nitrate reductase(NR)activity were significantly correlated.Melatonin and dopamine were also found to recruit different candidate beneficial endophytes(melatonin:Novosphingobium,Propionivibrio,and Cellvibrio;dopamine:Hydrogenophaga,Simplicispira,Methyloversatilis,Candidatus_Kaiserbacteria,and Humicola),and these endophytes were significantly and positively correlated with plant growth.Network analyses showed that melatonin and dopamine significantly affected the endophytic bacterial and fungal communities under waterlogging stress.The metabolomic results showed that melatonin and dopamine led to waterlogging resistance by upregulating the abundance of beneficial substances such as amino acids,flavonoids,coumarins,and organic acids.In addition,melatonin and dopamine regulated the physicochemical properties of the soil,which altered the endophyte community and affected plant growth.The co-occurrence network demonstrated close and complex relationships among endophytes,metabolites,soil,and the plants.Our results demonstrate that melatonin and dopamine alleviate waterlogging stress in apples by recruiting beneficial endophytes to enhance physiological resilience.This study provides new insights into how melatonin and dopamine alleviate stress and a theoretical basis for synergistic beneficial microbial resistance to waterlogging stress.展开更多
Root-associated microbes play an essentialrole in mediating plant growth,health,and habitat adaptability.However,it is unknown which microbial taxa help develop host fitness and how habitats shape root-associated micr...Root-associated microbes play an essentialrole in mediating plant growth,health,and habitat adaptability.However,it is unknown which microbial taxa help develop host fitness and how habitats shape root-associated microbial assembly patterns.As an endemic species of subalpine forests in western Sichuan,China,Minjiang fir(Abies fargesii var.faxoniana)is dominant on cold-shaded northwestern slopes while absent on warm sunlit southwestern slopes.In this study,fungal and bacterial communities were investigated in three spatial compartments(endosphere,rhizosphere,and bulk soil)associated with Minjiang fir saplings on a cold-shaded northwestern slope and a warm sunlit southwestern slope.Habitats differentiated the microbial communities regardless of the spatial compartment and microbial taxa.Slope aspect variations caused shifts in root-associated(rhizosphere and endosphere)microbial compositions.Compared with the southwestern slope,the cold-shaded northwestern slope harbored a higher abundance of the growth-promoting bacteria Burkholderia and ectomycorrhizal fungi Cortinarius and Piloderma.The slope aspect had stronger effects on fungal diversity than bacterial diversity,with higher fungal endemism and lower bacterial endemism.Slope aspect variations were the dominant drivers of root-associated microbial communities,with lower contribution by soil properties and higher contribution by plant traits on the northwestern slope.Findings from this study could improve the understanding of plant habitat adaptability from the perspective of microbial community assembly.It is suggested that forest management should consider root-associated microbiomes for enhancing species fitness and habitat adaptability.展开更多
Common wheat (Triticum aestivum L.) is one of the most important food crops. Powdery mildew, caused by Blumeria graminis f. sp. tritici (Bgt), is one of the most serious diseases on wheat. In this study, the changes o...Common wheat (Triticum aestivum L.) is one of the most important food crops. Powdery mildew, caused by Blumeria graminis f. sp. tritici (Bgt), is one of the most serious diseases on wheat. In this study, the changes of endogenous bacteria in root, stem and leaf tissues of wheat infected and uninfected with powdery mildew were measured based on 16S rDNA. Integration, OTU cluster analysis, taxonomic analysis, diversity index, Shannon-Index curve, Rank-Abundance curve and PCoA analysis were carried out for each sample, and the roots, stems and leaves of different tissue parts were classified and summarized. The results showed that the infection of wheat powdery mildew had a certain effect on endophytic bacteria in stem tissue. There are also differences in the control and treatment of leaf tissue and root tissue. This indicated that endophytic bacteria were distributed differently in different parts of wheat.展开更多
Antibiotic resistance poses a significant global health threat, necessitating a thorough understanding of its prevalence in various ecological contexts. Medicinal plants, renowned for their therapeutic properties, hos...Antibiotic resistance poses a significant global health threat, necessitating a thorough understanding of its prevalence in various ecological contexts. Medicinal plants, renowned for their therapeutic properties, host endophytic bacteria that produce bioactive compounds. Understanding antibiotic resistance dynamics in these bacteria is vital for human health and antibiotic efficacy preservation. In this study, we investigated antibiotic resistance profiles in endophytic bacteria from five medicinal plants: Thankuni, Neem, Aparajita, Joba, and Snake plant. We isolated and characterized 113 endophytic bacteria, with varying resistance patterns observed against multiple antibiotics. Notably, 53 strains were multidrug-resistant (MDR), with 14 exhibiting extensive drug resistance (XDR). Thankuni-associated bacteria displayed 44% MDR and 11% XDR, while Neem-associated bacteria showed higher resistance (60% MDR, 13% XDR). Aparajita-associated bacteria had lower resistance (22% MDR, 6% XDR), whereas Joba-associated bacteria exhibited substantial resistance (54% MDR, 14% XDR). Snake plant-associated bacteria showed 7% MDR and 4% XDR. Genus-specific distribution revealed Bacillus (47%), Staphylococcus (21%), and Klebsiella (11%) as major contributors to MDR. Our findings highlight diverse drug resistance patterns among plant-associated bacteria and underscore the complexity of antibiotic resistance dynamics in diverse plant environments. Identification of XDR strains emphasizes the severity of the antibiotic resistance problem, warranting further investigation into contributing factors.展开更多
Beneficial microbes can improve soil health by promoting soil structure,nutrient cycling,and disease suppression.In addition,a wide array of rhizospheric microbes are responsible for producing metabolically active comp...Beneficial microbes can improve soil health by promoting soil structure,nutrient cycling,and disease suppression.In addition,a wide array of rhizospheric microbes are responsible for producing metabolically active compounds including various types of plant growth regulators.So,microbial biodiversity studies could contribute to the improvement of agricultural practices in deprived areas,such as the Pampean semiarid region.The vast majority of studies conducted on endophytic microorganisms have focused on intensive crop legume species.In contrast,little attention has been paid to microorganisms of native legumes,whose ecology is not directly affected by human action.In this study,endophytic microorganisms isolated from root nodules of a selected native legume of the genus Rhynchosia were characterized.Viable isolates were studied with a focus on their plant growth-pro-moting rhizobacteria(PGPR)properties.Considering the edaphic characteristics of the Pampean semiarid region,the isolates obtained were evaluated for their ability to grow under three salt stress conditions(50,100,and 200 mM NaCl)and four different pH values(6,7,8,and 9).Based on their PGPR activities,the selected strains were phylogenetically grouped using BOX-PCR.The results showed great variability among the isolates in terms of the characteristics studied.Native legumes manifested a wide endophytic variability and remarkable perfor-mance in PGPR activities.We conclude that they could be used as potential bioinoculants for legume cultivation,an excellent alternative to the use of chemical fertilizers that currently pollute the environment.展开更多
Background:Completely endophytic renal tumors(CERT)pose significant challenges due to their anatomical complexity and loss of visual clues about tumor location.A facile scoring model based on three-dimensional(3D)reco...Background:Completely endophytic renal tumors(CERT)pose significant challenges due to their anatomical complexity and loss of visual clues about tumor location.A facile scoring model based on three-dimensional(3D)reconstructed images will assist in better assessing tumor location and vascular variations.Methods:In this retrospective study,80 patients diagnosed with CERT were included.Forty cases underwent preoperative assessment using 3D reconstructed imaging(3D-Cohort),while the remaining 40 cases were assessed using two-dimensional imaging(2D-Cohort).Vascular variations were evaluated by ascertaining the presence of renal arteries>1,prehilar branching arteries,and arteries anterior to veins.The proposed scoring system,termed RAL,encompassed three critical components:(R)adius(maximal tumor diameter in cm),(A)rtery(occurrence of arterial variations),and(L)ocation relative to the polar line.Comparison of the RAL scoring system was made with established nephrometry scoring systems.Results:A total of 48(60%)patients exhibited at least one vascular variation.In the 2D-Cohort,patients with vascular variations experienced significantly prolonged operation time,increased bleeding volume,and extended warm ischemia time compared with those without vascular variations.Conversely,the presence of vascular vari-ations did not significantly affect operative parameters in the 3D-Cohort.Furthermore,the 2D-Cohort demon-strated a notable decline in both short-and long-term estimated glomerular filtration rate(eGFR)changes com-pared with the 3D-Cohort,a trend consistent across patients with warm ischemia time≥25 min and those with vascular variations.Notably,the 2D-Cohort exhibited a larger margin of normal renal tissue compared with the 3D-Cohort.Elevated RAL scores correlated with larger tumor size,prolonged operation time,extended warm is-chemia time,and substantial postoperative eGFR decrease.The RAL scoring system displayed superior predictive capabilities in assessing postoperative eGFR changes compared with conventional nephrometry scoring systems.Conclusions:Our proposed 3D vascular variation-based nephrometry scoring system offers heightened proficiency in preoperative assessment,precise prediction of surgical complexity,and more accurate evaluation of postoper-ative renal function in CERT patients.展开更多
After insufflating extended endophytes phomopsis B3 ferment diluent on seedling bed of rice, the effect of microbial inoculum on rice growth was studied. The investigation result of seedlings before transplanting seed...After insufflating extended endophytes phomopsis B3 ferment diluent on seedling bed of rice, the effect of microbial inoculum on rice growth was studied. The investigation result of seedlings before transplanting seedling showed that leaf age,the number of green leaves,the number of tiller of individual plant and the weight of per 100 fresh plants in microbial inoculum treatment group increased 0.11,0.12 ,0. 03 and 2.6 g respectively compared with those of control group. 20 days after transplanting, increased tiller number in microbial inoculum treatment group was 55 500 hm^2 more than that in control group. 30 days after transplanting, tiller number in microbial inoculum treatment group was 42 000 hm^2 more than that in control group. In harvest season, the yield ,weight of I 0130 grain and seed-setting rate increased 300 kg/hm2, 0. 7 g and 0. 23% respectively compared with these in control group. The result of preliminary study demonstrated that microbial inoculum confected by endophytes phomopsis B3 could increase the number of strong seedling and yield.展开更多
Endophytes are hypothesized to be transferred across the soil-plant continuum, suggesting both the transfers of endophytes from environment to plant and from plant to soil. To verify this hypothesis and to assess the ...Endophytes are hypothesized to be transferred across the soil-plant continuum, suggesting both the transfers of endophytes from environment to plant and from plant to soil. To verify this hypothesis and to assess the role of locality, we evaluated the similarity of microbial communities commonly found both in soils and endophytic communities in three arid regions, i.e. the Jornada LTER (Long Term Ecological Research) site in New Mexico, USA, and the research station of Jordan University of Science and Technology (JUST) and Khanasd research station in Badia region of Jordan. Rhizosphere and non-rhizosphere soils, leaves and seeds of Atriplex spp. were sampled. Diversity and distribution of bacteria and fungi across the soil-plant continuums were assessed by tag-encoded FLX amplicon pyrosequencing and sequence alignment. Of the total bacterial OTUs (operational taxonomic units), 0.17% in Khanasri research station, 0.16% in research station of JUST, and 0.42% in Jornada LTER site were commonly found across all the plant and soil compartments. The same was true for fungi in two regions, i.e. 1.56% in research station of JUST and 0.86% in Jornada LTER site. However, in Khanasri research station, 12.08% of total fungi OTUs were found in at least one soil compartment and one plant compartment. Putative Arthrobacter, Sporosarcina, Cladosporium and members of Proteobacteria and Actinobacteria were found across all the soil-plant continuums. Ascomycota, mainly including Didymellaceae, Pleosporaceae and Davidiellaceae were present across all the soil-plant continuums. Microbial communities in two regions of Jordan were similar to each other, but both of them were different from the Jornada LTER site of USA. SIMPER (similarity percentage) analysis of bacterial and fungal taxa for both soil and endophyte communities revealed that dissimilarities of two bacterial genera (Arthrobacter and Sporosarcina) and two fungal genera (Cladosporium and Alternaria) are very high, so they play key roles in the soil-plant continuums. A weighed Pearson correlation analysis for the specific bacterial OTUs in the soil-plant continuums only showed high similarity between the two regions of Jordan. However, fungal groups showed higher similarities among all regions. This research supports the hypothesis of continuity of certain bacterial and fungal communities across the soil-plant continuums, and also explores the influences of plant species and geographic specificity on diversity and distribution of bacteria and fungi.展开更多
An endophyte is a fungus or bacterium that lives within a plant in a symbiotic relationship.Extensive colonization of the plant tissue by endophytes creates a barrier effect,where they outcompete and prevent pathogen...An endophyte is a fungus or bacterium that lives within a plant in a symbiotic relationship.Extensive colonization of the plant tissue by endophytes creates a barrier effect,where they outcompete and prevent pathogenic organisms from taking hold.This happens by producing secondary metabolites that inhibit the growth of the competitors or pathogens.In this way they play a very important role in the plant defence mechanisms.The metabolites produced by these endophytes fall within a wide range of classes of compounds that include peptides which are the focus of this review.Peptides are increasingly being selected for drug development because they are specific for their targets and have a higher degree of interactions.There have been quite a number of endophytic peptides reported in the recent past indicating that endophytes can be used for the production of peptide based drugs.Molecular screening for NRPS,which shows peptide producing capability,has also shown that endophytes are potential producers of peptides.The presence of NRPS also offers the possibility of genetic modifications which may generate peptides with high pharmacological activities.This review,therefore,aims to show the current status of peptides isolated from endophytic bacteria and fungi in the recent decade.Endophytes as potential sources of peptides according to NRPS studies will also be discussed.展开更多
Bacterial endophytes have been shown to improve abiotic and biotic stress responses in plants. Plants growing under harsh conditions along the Oregon Coast could contain bacterial endophytes that improve persistence a...Bacterial endophytes have been shown to improve abiotic and biotic stress responses in plants. Plants growing under harsh conditions along the Oregon Coast could contain bacterial endophytes that improve persistence and growth of grasses in this environment. Thirty-four plants consisting of eight different species were collected along the Oregon coast from four different sites. Bacterial endophytes were isolated from root crown, stem and leaf tissues. A portion of the 16S rRNA ITS regions of each isolate was amplified, sequenced, and used to perform a BLAST search against the nucleotide database collection at National Center for Biotechnology Information. One-hundred and thirty-three different bacterial isolates, ninety-four of which were unique, representing thirty-six different taxonomic groups were found. Over 50% of the total bacteria isolates were in just five taxonomic groups. Pseudomonads were the most predominant bacteria isolated, making up 20.3% of the total isolates, followed by Curtobacterium and Microbacterium, each at 8.2%, Bacillus at 7.5% and Xanthomomas at 6%. Forty-seven percent (17 of 36) of the taxonomic groups contained only a single isolate. Fourteen bacterial isolates from five taxonomic groups, nine of which were from the genus Pseudomonas, were found to have 1-aminocyclopropane-1-carboxylate (ACC) deaminase activity, an enzyme associated with improving plant growth under stress. These newly discovered bacterial endophytes will be a valuable biological resource to develop approaches to increase the yield and adaptability of grasses and other crops grown in diverse environments and to meet the challenges associated with an unpredictable climate.展开更多
Leishmaniases and chronic inflammatory diseases are the cause of millions of deaths in the world each year.The treatment of leishmaniasis is facing serious drawbacks particularly due to the limited number of effective...Leishmaniases and chronic inflammatory diseases are the cause of millions of deaths in the world each year.The treatment of leishmaniasis is facing serious drawbacks particularly due to the limited number of effective medicines,the resistance,and the toxicity of available drugs.On the other hand,many drugs are used for the management of inflammatory disorders.However,the most commonly prescribed although efficient is highly toxic with multiples side effects.New leads compounds for the development of new anti-leishmanial and anti-inflammatory drugs are needed.Over the past decade,several studies on the potential of endophytes to produce bioactive metabolites have been reported.We are presenting in the present review the status of research from 2000 to 2019 on the anti-leishmanial and anti-inflammatory metabolites isolated from endophytes from diverse habitats.An emphasis was put on existing gaps in the literature to inspire and guide future investigations.We hope that this review will help accelerate the drug discovery against leishmaniases and inflammation-associated disorders.展开更多
We used standard isolation protocols to explore the endophytic fungal communities in three tissue types of two dominant orchids (Bulbophyllum neilgherrense and Vanda testacea) of the Kaiga forest of the Western Ghat...We used standard isolation protocols to explore the endophytic fungal communities in three tissue types of two dominant orchids (Bulbophyllum neilgherrense and Vanda testacea) of the Kaiga forest of the Western Ghats. We surface sterilized and assessed 90 segments of each orchid for the occurrence and diversity of endophytic fungal taxa. The 118 fungal isolates were obtained from root, bulb and leaves of B. neilgherrense, consisting of 17 anamorphic taxa (range, 10-15 taxa) with 1.3 fungal taxa per segment (range, 1.2-1.4 taxa). Four taxa (Aspergillus flavus, A. niger, Penicillium sp. and morpho sp. 1) belonged to the core group (11.1%--32.2%). The relative abundance of A. flavus and morpho sp. 1 was more than 10%. A total of 130 fungal isolates from roots, stems and leaves of V. testacea yielded 20 anamorphic taxa (range, 11-15 taxa) with 1.4 fungal taxa per segment (range, 1.4-1.5 taxa). Aspergillusflavus, A. niger, A. ochraceus, Gliocladium viride, Penicillium sp. and morpho sp. 1 belonged to the core group. Relative abundance exceeded 10% for A. flavus, A. niger, and morpho sp. 1. The Simpson and Shannon diversity indices were higher in leaf than root or bulb/stem of both orchids. Jaccard's similarity coefficient was higher between root and leaf in both orchids (56.3%-60%) than between other pairs. Our study revealed that the endophytic fungal assemblage and diversity orB. neilgherrense and E testacea of Kaiga forest of the Western Ghats were relatively similar between orchids and their tissues.展开更多
Seaweeds are known to exhibit various antimicrobial properties, since it harbours an enormous range of indigenous bioactive compounds. The emergence of drug resistant strains has directed to the identification of pros...Seaweeds are known to exhibit various antimicrobial properties, since it harbours an enormous range of indigenous bioactive compounds. The emergence of drug resistant strains has directed to the identification of prospective metabolites from seaweed and its endophytes, thereby exploiting the properties in resisting bacterial diseases. The current study was aimed to assess the antimicrobial activity of extracts obtained from Ulva reticulate, for which metabolites of Ulva reticulata and its endophytes were extracted and assessed against human pathogens like Staphylococcus aureus, Escherichia coli, Pseudomonas aeruginosa, Salmonella typhi, and Bacillus subtilis. It was observed that the hexane extract of isolate VITDSJ2 was effective against all the tested pathogens but a significant inhibition was observed for Staphylococcus aureus and Escherichia coli. Further, Gas chromatography coupled with Mass spectroscopy (GC-MS) revealed the existence of phenol, 3, 5-bis (1, 1-dimethylethyl) in the crude hexane extract which is well-known to possess antibacterial activity. The effective isolate VITDSJ2 was identified to be the closest neighbour of Pseudomonas smtzeri by phenotypic and genotypic methods. The crude extracts of the seaweed Ulva reticulata was also screened for antibacterial activity and the hexane extract was effective in showing inhibition against all the tested pathogens. The compound in the crude extract of Ulva reticulata was identified as hentriacontane using GC-MS. The extracts obtained from dichloromethane did not show significant activity in comparison with the hexane extracts. Hence the metabolites of Ulva reticulata and the bacterial secondary metabolites of the endophytes could be used in the treatment of bacterial infections.展开更多
The study was taken up with the objective of testing whether the endophytic organisms isolated from crops that are normally non-hosts to the bacterial wilt pathogen Ralstonia solanacearum possessed pathogen-antagonist...The study was taken up with the objective of testing whether the endophytic organisms isolated from crops that are normally non-hosts to the bacterial wilt pathogen Ralstonia solanacearum possessed pathogen-antagonistic activity and to evaluate the selected isolates for the alleviation of wilt disease in the target tomato crop through horizontal movement of promising organisms. Sixteen endophytic bacteria (EB) isolated from the micropropagated cultures of grape, watermelon and papaya were tested for potential antagonistic effects against R. solanacearum tomato isolate “NH-01” through agar-well diffusion assay. Enterobacter cloacae from papaya (EB-11) displayed the maximum antagonistic effect followed by Bacillus subtilis (EB-06) and B. flexus (EB-07) from watermelon and B. pumilus (EB-02) from grape. Testing the above organisms for crop protection through seed fortification of susceptible tomato cv. Arka Vikas at sowing in R. solanacearum inoculated (Ral+) organic cocopeat showed EB-02 and EB-11 promising (33% and 32% survival, respectively, four weeks after sowing against 15% in Ral+ control). A second trial showed 37%, 28%, 21% and 55% seedling survival 6 weeks after sowing for EB-02, EB-06, EB-07 and EB-11 respectively, compared to 2.5% in non-treated control. Assessing the four endophytes for crop protection in Ral+ sick-soil through seedling fortification at transplanting indicated less disease incidence in treated sets (40%, 40%, 20% and 20% survival, respectively, six weeks after transplanting) over non-fortified control (5%). Endophytic fortification of seedlings through hypocotyl inoculation showed some systemic resistance induction upon seedling transplanting to sick soil but not with petiole fortification. Seedling growth was enhanced by the isolates EB-06 and EB-07. The study thus identifies four endophytic organisms from crops unrelated to tomato possessing potential antagonistic activity against the wilt pathogen and prospects for exploitation as biocontrol agents coupled with seedling growth promotion effects.展开更多
Green coffee seeds from Colombia, Guatemala, India, Kenya, Papua New Guinea, Puerto Rico and Vietnam were sampled for the presence of fungal endophytes. Stions of surface sterilized seeds were plated on yeast malt aga...Green coffee seeds from Colombia, Guatemala, India, Kenya, Papua New Guinea, Puerto Rico and Vietnam were sampled for the presence of fungal endophytes. Stions of surface sterilized seeds were plated on yeast malt agar, and fungal growth was isolated for subsequent DNA extraction and sequencing. Several fungal genera were isolated, including Acremonium, Aspergillus, Eurotium, Fusarium, Gibberella, Penicillium, Pseudozyma and an undescribed clavicipitaceous species. The biological activities that these fungi might be playing in coffee seeds remain unknown, but in other plants some of the genera isolated have been reported to protect against plant pathogens.展开更多
The aim of this study is to investigate in vitro antioxidant activities and the phytochemical screening endophytes. Seven different endophytic fungi were isolated from different parts of the plant and their extracts s...The aim of this study is to investigate in vitro antioxidant activities and the phytochemical screening endophytes. Seven different endophytic fungi were isolated from different parts of the plant and their extracts subjected to know antioxidant properties and phytochemical screening. Phytochemical analysis revealed the presence of tannins, flavonoids, steroids, alkaloids, phenols and proteins from different solvents extracts of different endophytes. The antioxidant activity was evaluated by six separated methods: scavenging of free radical DPPH, FRAP, TBA, superoxide radical, FTC and iron methods. All seven different endophytes yielded almost all phytochemicals in methanol extracts which were tested. The endophytes A. niger, Penicillium sp. and Trichoderma sp. have shown potential in vitro antioxidant activities. Further work is needful to isolate the exact compound which is responsible for antioxidant activity and biophysical characterization will be done in the future.展开更多
Fungal endophytes have been shown to improve abiotic and biotic stress response in plants. Grasses growing along the Oregon coast are exposed to harsh conditions and may harbor endophytes that enable them to survive a...Fungal endophytes have been shown to improve abiotic and biotic stress response in plants. Grasses growing along the Oregon coast are exposed to harsh conditions and may harbor endophytes that enable them to survive and grow under these conditions. Endophytic fungi were isolated from thirty-four grass plants representing eight different grass species at four different locations along the Oregon coast. The ITS-1, 5.8S, and ITS-2 regions of each isolate were amplified, sequenced, and used to perform a BLAST search against the nucleotide database collection at National Center for Biotechnology Information. One-hundred-eleven different fungal isolates were classified into thirtynine genera with two isolates that did not show a match greater than 95%. These endophytes will be investigated to determine their potential for improving the adaptability of grasses and other crop plants to grow in diverse environments where they are subjected to multiple biotic and abiotic stresses.展开更多
This study aims to isolate and identify taxonomic characterization of endophytic fungi from bitter melon in Guangdong province, China. A total of 1172 endophytic fungi are isolated from roots, stems, leaves, flowers, ...This study aims to isolate and identify taxonomic characterization of endophytic fungi from bitter melon in Guangdong province, China. A total of 1172 endophytic fungi are isolated from roots, stems, leaves, flowers, and fruits of healthy plants, and they are classified to 49 taxa based on morphological and molecular features. The results show that endophytic fungi from bitter melon plants exhibit high biodiversity. Arthrinium aureum, A. marii, A. sphaerospermum, Corynascus verrucosus, Curvularia borreriae and C. protuberate have not been recorded in any plants in China. Basidiomycetous endophytes, such as Ceratobasidium sp., and C. cornigerum, are reported in this study for the first time in bitter melon. According to the results of phylogenetic analysis, the rDNA ITS (Internal Transcribed Spacer) sequences can successfully separate species, such as F. solani, F. kyushuense, C. verrucosus, C. globosum, E. rostratum, C. brachyspora, C. verruculosus, C. affinis, P. bougainvilleicola, P. longicolla, P. glabrae, P. verruculosum, P. oxalicum, P. citrinum, P. chermesinum, P. glomerata, A. fumigatus and A. japonicas. Some isolates belonging to A. alternata, C. gloeosporioides, C. cladosporioides, C. brasiliense, C. convolutum, F. proliferatum, F. oxysporum, F. verticillioides, F. equiseti, F. camptoceras and Xylaria, however, require the analysis of others molecular markers to provide better taxonomic resolution. Molecular analyses of rDNA ITS sequences are useful for identification and classification of endophytes of bitter melon, but it is desirable to consider an integrated approach, such as molecular phylogeny, host, colony growth rate, symptoms, and shape of conidia.展开更多
基金supported by the Plan in Scientific and Technological Innovation Team of Outstanding Young Scientists,Hubei Provincial Department of Education (Grant No.T201604)。
文摘Root-associated endophytic fungi like Serendipita indica and arbuscular mycorrhizal(AM) fungi can improve plant growth and root construction, but the potential mechanism is unclear. In this study, Funneliformis mosseae(an AM fungus) and S. indica, singly or in combination were inoculated into trifoliate orange(Poncirus trifoliata) seedlings, to assess changes in biomass and root morphological traits, coupled with auxins and cytokinins concentrations in leaves and roots and the expression of auxin synthesis and transporter protein genes. After 20 weeks of inoculation with these fungi, shoot and root biomass, root total length, taproot length, average diameter, surface area, volume, and the number of lateral roots in 1st-, 2nd-, and 3rd-order were improved, and S. indica showed a relatively greater effect than F. mosseae and dual inoculation. Endophytic fungal inoculation also significantly increased the concentration of indoleacetic acid, indole butyric acid, trans-zeatin,dihydrozeatin, and isopentenyl adenine in leaves and roots, whilst F. mosseae and S. indica exhibited relatively greater effects on leaves and roots, respectively. Correlation analysis revealed that both biomass and root morphological traits(except root projected area) were significantly positively associated with endogenous auxins and cytokinins. In addition, the inoculated plants recorded comparatively higher expression levels of indoleacetic acid synthesis genes(PtTAA1, PtTAR2, PtYUC3, PtYUC4, PtYUC6, and PtYUC8) and indoleacetic acid transporter protein genes(PtAUX1, PtLAX1, PtLAX2, PtLAX3, PtPIN1, PtPIN3, PtPIN4, PtABCB1, and PtABCB19) than the non-inoculated plants, among which F. mosseae and S. indica showed better effects in leaves and roots, respectively. These results suggest that root-associated endophytic fungi improved plant growth and root architecture, which were associated with changes in endogenous auxins and cytokinins.
基金supported by the National Natural Science Foundation of China(31901964)the Natural Science Foundation of Hebei,China(C2021204158)+3 种基金the Science and Technology Project of Hebei Education Department,China(BJK2022012)the Introduced Talents Project of Hebei Agricultural University,China(YJ201904)the earmarked fund for Hebei Apple Innovation Team of Modern Agroindustry Technology Research System,China(HBCT2024150205)the earmarked fund for the China Agricultural Research System,China(CARS-27).
文摘Melatonin and dopamine can potentially prevent waterlogging stress in apples.The current study investigated the mechanism by which melatonin and dopamine alleviate apple waterlogging stress.This study demonstrated that melatonin and dopamine alleviated waterlogging by removing reactive oxygen species(ROS),and that the nitric oxide(NO)content and nitrate reductase(NR)activity were significantly correlated.Melatonin and dopamine were also found to recruit different candidate beneficial endophytes(melatonin:Novosphingobium,Propionivibrio,and Cellvibrio;dopamine:Hydrogenophaga,Simplicispira,Methyloversatilis,Candidatus_Kaiserbacteria,and Humicola),and these endophytes were significantly and positively correlated with plant growth.Network analyses showed that melatonin and dopamine significantly affected the endophytic bacterial and fungal communities under waterlogging stress.The metabolomic results showed that melatonin and dopamine led to waterlogging resistance by upregulating the abundance of beneficial substances such as amino acids,flavonoids,coumarins,and organic acids.In addition,melatonin and dopamine regulated the physicochemical properties of the soil,which altered the endophyte community and affected plant growth.The co-occurrence network demonstrated close and complex relationships among endophytes,metabolites,soil,and the plants.Our results demonstrate that melatonin and dopamine alleviate waterlogging stress in apples by recruiting beneficial endophytes to enhance physiological resilience.This study provides new insights into how melatonin and dopamine alleviate stress and a theoretical basis for synergistic beneficial microbial resistance to waterlogging stress.
基金jointly funded by the National Key Research and Development Program of China (No.2021YFD2200405)the National Natural Science Foundation of China (No.31930078)。
文摘Root-associated microbes play an essentialrole in mediating plant growth,health,and habitat adaptability.However,it is unknown which microbial taxa help develop host fitness and how habitats shape root-associated microbial assembly patterns.As an endemic species of subalpine forests in western Sichuan,China,Minjiang fir(Abies fargesii var.faxoniana)is dominant on cold-shaded northwestern slopes while absent on warm sunlit southwestern slopes.In this study,fungal and bacterial communities were investigated in three spatial compartments(endosphere,rhizosphere,and bulk soil)associated with Minjiang fir saplings on a cold-shaded northwestern slope and a warm sunlit southwestern slope.Habitats differentiated the microbial communities regardless of the spatial compartment and microbial taxa.Slope aspect variations caused shifts in root-associated(rhizosphere and endosphere)microbial compositions.Compared with the southwestern slope,the cold-shaded northwestern slope harbored a higher abundance of the growth-promoting bacteria Burkholderia and ectomycorrhizal fungi Cortinarius and Piloderma.The slope aspect had stronger effects on fungal diversity than bacterial diversity,with higher fungal endemism and lower bacterial endemism.Slope aspect variations were the dominant drivers of root-associated microbial communities,with lower contribution by soil properties and higher contribution by plant traits on the northwestern slope.Findings from this study could improve the understanding of plant habitat adaptability from the perspective of microbial community assembly.It is suggested that forest management should consider root-associated microbiomes for enhancing species fitness and habitat adaptability.
文摘Common wheat (Triticum aestivum L.) is one of the most important food crops. Powdery mildew, caused by Blumeria graminis f. sp. tritici (Bgt), is one of the most serious diseases on wheat. In this study, the changes of endogenous bacteria in root, stem and leaf tissues of wheat infected and uninfected with powdery mildew were measured based on 16S rDNA. Integration, OTU cluster analysis, taxonomic analysis, diversity index, Shannon-Index curve, Rank-Abundance curve and PCoA analysis were carried out for each sample, and the roots, stems and leaves of different tissue parts were classified and summarized. The results showed that the infection of wheat powdery mildew had a certain effect on endophytic bacteria in stem tissue. There are also differences in the control and treatment of leaf tissue and root tissue. This indicated that endophytic bacteria were distributed differently in different parts of wheat.
文摘Antibiotic resistance poses a significant global health threat, necessitating a thorough understanding of its prevalence in various ecological contexts. Medicinal plants, renowned for their therapeutic properties, host endophytic bacteria that produce bioactive compounds. Understanding antibiotic resistance dynamics in these bacteria is vital for human health and antibiotic efficacy preservation. In this study, we investigated antibiotic resistance profiles in endophytic bacteria from five medicinal plants: Thankuni, Neem, Aparajita, Joba, and Snake plant. We isolated and characterized 113 endophytic bacteria, with varying resistance patterns observed against multiple antibiotics. Notably, 53 strains were multidrug-resistant (MDR), with 14 exhibiting extensive drug resistance (XDR). Thankuni-associated bacteria displayed 44% MDR and 11% XDR, while Neem-associated bacteria showed higher resistance (60% MDR, 13% XDR). Aparajita-associated bacteria had lower resistance (22% MDR, 6% XDR), whereas Joba-associated bacteria exhibited substantial resistance (54% MDR, 14% XDR). Snake plant-associated bacteria showed 7% MDR and 4% XDR. Genus-specific distribution revealed Bacillus (47%), Staphylococcus (21%), and Klebsiella (11%) as major contributors to MDR. Our findings highlight diverse drug resistance patterns among plant-associated bacteria and underscore the complexity of antibiotic resistance dynamics in diverse plant environments. Identification of XDR strains emphasizes the severity of the antibiotic resistance problem, warranting further investigation into contributing factors.
基金supported by Facultad de Ciencias Exactas y Naturales de la Universidad Nacional de La Pampa(FCEyN-UNLPam).
文摘Beneficial microbes can improve soil health by promoting soil structure,nutrient cycling,and disease suppression.In addition,a wide array of rhizospheric microbes are responsible for producing metabolically active compounds including various types of plant growth regulators.So,microbial biodiversity studies could contribute to the improvement of agricultural practices in deprived areas,such as the Pampean semiarid region.The vast majority of studies conducted on endophytic microorganisms have focused on intensive crop legume species.In contrast,little attention has been paid to microorganisms of native legumes,whose ecology is not directly affected by human action.In this study,endophytic microorganisms isolated from root nodules of a selected native legume of the genus Rhynchosia were characterized.Viable isolates were studied with a focus on their plant growth-pro-moting rhizobacteria(PGPR)properties.Considering the edaphic characteristics of the Pampean semiarid region,the isolates obtained were evaluated for their ability to grow under three salt stress conditions(50,100,and 200 mM NaCl)and four different pH values(6,7,8,and 9).Based on their PGPR activities,the selected strains were phylogenetically grouped using BOX-PCR.The results showed great variability among the isolates in terms of the characteristics studied.Native legumes manifested a wide endophytic variability and remarkable perfor-mance in PGPR activities.We conclude that they could be used as potential bioinoculants for legume cultivation,an excellent alternative to the use of chemical fertilizers that currently pollute the environment.
基金We thank researchers for patients enrolled from the FUSCC cohort.This work was supported by grants from the National Natural Science Foundation of China(grant numbers:81802525 and no.82172817)the Natural Science Foundation of Shanghai(grant number:20ZR1413100)+3 种基金Beijing Xisike Clinical Oncology Research Foundation(grant number:Y-HR2020MS-0948)the Shanghai“Science and Technology Innova-tion Action Plan”medical innovation research Project(grant num-ber:22Y11905100)the Shanghai Anti-Cancer Association Eyas Project(grant number:SACA-CY21A06 and no.SACA-CY21B01)Fudan University Fuqing scholars Project(grant number:FQXZ202304A).
文摘Background:Completely endophytic renal tumors(CERT)pose significant challenges due to their anatomical complexity and loss of visual clues about tumor location.A facile scoring model based on three-dimensional(3D)reconstructed images will assist in better assessing tumor location and vascular variations.Methods:In this retrospective study,80 patients diagnosed with CERT were included.Forty cases underwent preoperative assessment using 3D reconstructed imaging(3D-Cohort),while the remaining 40 cases were assessed using two-dimensional imaging(2D-Cohort).Vascular variations were evaluated by ascertaining the presence of renal arteries>1,prehilar branching arteries,and arteries anterior to veins.The proposed scoring system,termed RAL,encompassed three critical components:(R)adius(maximal tumor diameter in cm),(A)rtery(occurrence of arterial variations),and(L)ocation relative to the polar line.Comparison of the RAL scoring system was made with established nephrometry scoring systems.Results:A total of 48(60%)patients exhibited at least one vascular variation.In the 2D-Cohort,patients with vascular variations experienced significantly prolonged operation time,increased bleeding volume,and extended warm ischemia time compared with those without vascular variations.Conversely,the presence of vascular vari-ations did not significantly affect operative parameters in the 3D-Cohort.Furthermore,the 2D-Cohort demon-strated a notable decline in both short-and long-term estimated glomerular filtration rate(eGFR)changes com-pared with the 3D-Cohort,a trend consistent across patients with warm ischemia time≥25 min and those with vascular variations.Notably,the 2D-Cohort exhibited a larger margin of normal renal tissue compared with the 3D-Cohort.Elevated RAL scores correlated with larger tumor size,prolonged operation time,extended warm is-chemia time,and substantial postoperative eGFR decrease.The RAL scoring system displayed superior predictive capabilities in assessing postoperative eGFR changes compared with conventional nephrometry scoring systems.Conclusions:Our proposed 3D vascular variation-based nephrometry scoring system offers heightened proficiency in preoperative assessment,precise prediction of surgical complexity,and more accurate evaluation of postoper-ative renal function in CERT patients.
基金Supported by the National Natural Science Foundation of China(30770073,30500066)~~
文摘After insufflating extended endophytes phomopsis B3 ferment diluent on seedling bed of rice, the effect of microbial inoculum on rice growth was studied. The investigation result of seedlings before transplanting seedling showed that leaf age,the number of green leaves,the number of tiller of individual plant and the weight of per 100 fresh plants in microbial inoculum treatment group increased 0.11,0.12 ,0. 03 and 2.6 g respectively compared with those of control group. 20 days after transplanting, increased tiller number in microbial inoculum treatment group was 55 500 hm^2 more than that in control group. 30 days after transplanting, tiller number in microbial inoculum treatment group was 42 000 hm^2 more than that in control group. In harvest season, the yield ,weight of I 0130 grain and seed-setting rate increased 300 kg/hm2, 0. 7 g and 0. 23% respectively compared with these in control group. The result of preliminary study demonstrated that microbial inoculum confected by endophytes phomopsis B3 could increase the number of strong seedling and yield.
文摘Endophytes are hypothesized to be transferred across the soil-plant continuum, suggesting both the transfers of endophytes from environment to plant and from plant to soil. To verify this hypothesis and to assess the role of locality, we evaluated the similarity of microbial communities commonly found both in soils and endophytic communities in three arid regions, i.e. the Jornada LTER (Long Term Ecological Research) site in New Mexico, USA, and the research station of Jordan University of Science and Technology (JUST) and Khanasd research station in Badia region of Jordan. Rhizosphere and non-rhizosphere soils, leaves and seeds of Atriplex spp. were sampled. Diversity and distribution of bacteria and fungi across the soil-plant continuums were assessed by tag-encoded FLX amplicon pyrosequencing and sequence alignment. Of the total bacterial OTUs (operational taxonomic units), 0.17% in Khanasri research station, 0.16% in research station of JUST, and 0.42% in Jornada LTER site were commonly found across all the plant and soil compartments. The same was true for fungi in two regions, i.e. 1.56% in research station of JUST and 0.86% in Jornada LTER site. However, in Khanasri research station, 12.08% of total fungi OTUs were found in at least one soil compartment and one plant compartment. Putative Arthrobacter, Sporosarcina, Cladosporium and members of Proteobacteria and Actinobacteria were found across all the soil-plant continuums. Ascomycota, mainly including Didymellaceae, Pleosporaceae and Davidiellaceae were present across all the soil-plant continuums. Microbial communities in two regions of Jordan were similar to each other, but both of them were different from the Jornada LTER site of USA. SIMPER (similarity percentage) analysis of bacterial and fungal taxa for both soil and endophyte communities revealed that dissimilarities of two bacterial genera (Arthrobacter and Sporosarcina) and two fungal genera (Cladosporium and Alternaria) are very high, so they play key roles in the soil-plant continuums. A weighed Pearson correlation analysis for the specific bacterial OTUs in the soil-plant continuums only showed high similarity between the two regions of Jordan. However, fungal groups showed higher similarities among all regions. This research supports the hypothesis of continuity of certain bacterial and fungal communities across the soil-plant continuums, and also explores the influences of plant species and geographic specificity on diversity and distribution of bacteria and fungi.
文摘An endophyte is a fungus or bacterium that lives within a plant in a symbiotic relationship.Extensive colonization of the plant tissue by endophytes creates a barrier effect,where they outcompete and prevent pathogenic organisms from taking hold.This happens by producing secondary metabolites that inhibit the growth of the competitors or pathogens.In this way they play a very important role in the plant defence mechanisms.The metabolites produced by these endophytes fall within a wide range of classes of compounds that include peptides which are the focus of this review.Peptides are increasingly being selected for drug development because they are specific for their targets and have a higher degree of interactions.There have been quite a number of endophytic peptides reported in the recent past indicating that endophytes can be used for the production of peptide based drugs.Molecular screening for NRPS,which shows peptide producing capability,has also shown that endophytes are potential producers of peptides.The presence of NRPS also offers the possibility of genetic modifications which may generate peptides with high pharmacological activities.This review,therefore,aims to show the current status of peptides isolated from endophytic bacteria and fungi in the recent decade.Endophytes as potential sources of peptides according to NRPS studies will also be discussed.
文摘Bacterial endophytes have been shown to improve abiotic and biotic stress responses in plants. Plants growing under harsh conditions along the Oregon Coast could contain bacterial endophytes that improve persistence and growth of grasses in this environment. Thirty-four plants consisting of eight different species were collected along the Oregon coast from four different sites. Bacterial endophytes were isolated from root crown, stem and leaf tissues. A portion of the 16S rRNA ITS regions of each isolate was amplified, sequenced, and used to perform a BLAST search against the nucleotide database collection at National Center for Biotechnology Information. One-hundred and thirty-three different bacterial isolates, ninety-four of which were unique, representing thirty-six different taxonomic groups were found. Over 50% of the total bacteria isolates were in just five taxonomic groups. Pseudomonads were the most predominant bacteria isolated, making up 20.3% of the total isolates, followed by Curtobacterium and Microbacterium, each at 8.2%, Bacillus at 7.5% and Xanthomomas at 6%. Forty-seven percent (17 of 36) of the taxonomic groups contained only a single isolate. Fourteen bacterial isolates from five taxonomic groups, nine of which were from the genus Pseudomonas, were found to have 1-aminocyclopropane-1-carboxylate (ACC) deaminase activity, an enzyme associated with improving plant growth under stress. These newly discovered bacterial endophytes will be a valuable biological resource to develop approaches to increase the yield and adaptability of grasses and other crops grown in diverse environments and to meet the challenges associated with an unpredictable climate.
文摘Leishmaniases and chronic inflammatory diseases are the cause of millions of deaths in the world each year.The treatment of leishmaniasis is facing serious drawbacks particularly due to the limited number of effective medicines,the resistance,and the toxicity of available drugs.On the other hand,many drugs are used for the management of inflammatory disorders.However,the most commonly prescribed although efficient is highly toxic with multiples side effects.New leads compounds for the development of new anti-leishmanial and anti-inflammatory drugs are needed.Over the past decade,several studies on the potential of endophytes to produce bioactive metabolites have been reported.We are presenting in the present review the status of research from 2000 to 2019 on the anti-leishmanial and anti-inflammatory metabolites isolated from endophytes from diverse habitats.An emphasis was put on existing gaps in the literature to inspire and guide future investigations.We hope that this review will help accelerate the drug discovery against leishmaniases and inflammation-associated disorders.
文摘We used standard isolation protocols to explore the endophytic fungal communities in three tissue types of two dominant orchids (Bulbophyllum neilgherrense and Vanda testacea) of the Kaiga forest of the Western Ghats. We surface sterilized and assessed 90 segments of each orchid for the occurrence and diversity of endophytic fungal taxa. The 118 fungal isolates were obtained from root, bulb and leaves of B. neilgherrense, consisting of 17 anamorphic taxa (range, 10-15 taxa) with 1.3 fungal taxa per segment (range, 1.2-1.4 taxa). Four taxa (Aspergillus flavus, A. niger, Penicillium sp. and morpho sp. 1) belonged to the core group (11.1%--32.2%). The relative abundance of A. flavus and morpho sp. 1 was more than 10%. A total of 130 fungal isolates from roots, stems and leaves of V. testacea yielded 20 anamorphic taxa (range, 11-15 taxa) with 1.4 fungal taxa per segment (range, 1.4-1.5 taxa). Aspergillusflavus, A. niger, A. ochraceus, Gliocladium viride, Penicillium sp. and morpho sp. 1 belonged to the core group. Relative abundance exceeded 10% for A. flavus, A. niger, and morpho sp. 1. The Simpson and Shannon diversity indices were higher in leaf than root or bulb/stem of both orchids. Jaccard's similarity coefficient was higher between root and leaf in both orchids (56.3%-60%) than between other pairs. Our study revealed that the endophytic fungal assemblage and diversity orB. neilgherrense and E testacea of Kaiga forest of the Western Ghats were relatively similar between orchids and their tissues.
文摘Seaweeds are known to exhibit various antimicrobial properties, since it harbours an enormous range of indigenous bioactive compounds. The emergence of drug resistant strains has directed to the identification of prospective metabolites from seaweed and its endophytes, thereby exploiting the properties in resisting bacterial diseases. The current study was aimed to assess the antimicrobial activity of extracts obtained from Ulva reticulate, for which metabolites of Ulva reticulata and its endophytes were extracted and assessed against human pathogens like Staphylococcus aureus, Escherichia coli, Pseudomonas aeruginosa, Salmonella typhi, and Bacillus subtilis. It was observed that the hexane extract of isolate VITDSJ2 was effective against all the tested pathogens but a significant inhibition was observed for Staphylococcus aureus and Escherichia coli. Further, Gas chromatography coupled with Mass spectroscopy (GC-MS) revealed the existence of phenol, 3, 5-bis (1, 1-dimethylethyl) in the crude hexane extract which is well-known to possess antibacterial activity. The effective isolate VITDSJ2 was identified to be the closest neighbour of Pseudomonas smtzeri by phenotypic and genotypic methods. The crude extracts of the seaweed Ulva reticulata was also screened for antibacterial activity and the hexane extract was effective in showing inhibition against all the tested pathogens. The compound in the crude extract of Ulva reticulata was identified as hentriacontane using GC-MS. The extracts obtained from dichloromethane did not show significant activity in comparison with the hexane extracts. Hence the metabolites of Ulva reticulata and the bacterial secondary metabolites of the endophytes could be used in the treatment of bacterial infections.
文摘The study was taken up with the objective of testing whether the endophytic organisms isolated from crops that are normally non-hosts to the bacterial wilt pathogen Ralstonia solanacearum possessed pathogen-antagonistic activity and to evaluate the selected isolates for the alleviation of wilt disease in the target tomato crop through horizontal movement of promising organisms. Sixteen endophytic bacteria (EB) isolated from the micropropagated cultures of grape, watermelon and papaya were tested for potential antagonistic effects against R. solanacearum tomato isolate “NH-01” through agar-well diffusion assay. Enterobacter cloacae from papaya (EB-11) displayed the maximum antagonistic effect followed by Bacillus subtilis (EB-06) and B. flexus (EB-07) from watermelon and B. pumilus (EB-02) from grape. Testing the above organisms for crop protection through seed fortification of susceptible tomato cv. Arka Vikas at sowing in R. solanacearum inoculated (Ral+) organic cocopeat showed EB-02 and EB-11 promising (33% and 32% survival, respectively, four weeks after sowing against 15% in Ral+ control). A second trial showed 37%, 28%, 21% and 55% seedling survival 6 weeks after sowing for EB-02, EB-06, EB-07 and EB-11 respectively, compared to 2.5% in non-treated control. Assessing the four endophytes for crop protection in Ral+ sick-soil through seedling fortification at transplanting indicated less disease incidence in treated sets (40%, 40%, 20% and 20% survival, respectively, six weeks after transplanting) over non-fortified control (5%). Endophytic fortification of seedlings through hypocotyl inoculation showed some systemic resistance induction upon seedling transplanting to sick soil but not with petiole fortification. Seedling growth was enhanced by the isolates EB-06 and EB-07. The study thus identifies four endophytic organisms from crops unrelated to tomato possessing potential antagonistic activity against the wilt pathogen and prospects for exploitation as biocontrol agents coupled with seedling growth promotion effects.
文摘Green coffee seeds from Colombia, Guatemala, India, Kenya, Papua New Guinea, Puerto Rico and Vietnam were sampled for the presence of fungal endophytes. Stions of surface sterilized seeds were plated on yeast malt agar, and fungal growth was isolated for subsequent DNA extraction and sequencing. Several fungal genera were isolated, including Acremonium, Aspergillus, Eurotium, Fusarium, Gibberella, Penicillium, Pseudozyma and an undescribed clavicipitaceous species. The biological activities that these fungi might be playing in coffee seeds remain unknown, but in other plants some of the genera isolated have been reported to protect against plant pathogens.
文摘The aim of this study is to investigate in vitro antioxidant activities and the phytochemical screening endophytes. Seven different endophytic fungi were isolated from different parts of the plant and their extracts subjected to know antioxidant properties and phytochemical screening. Phytochemical analysis revealed the presence of tannins, flavonoids, steroids, alkaloids, phenols and proteins from different solvents extracts of different endophytes. The antioxidant activity was evaluated by six separated methods: scavenging of free radical DPPH, FRAP, TBA, superoxide radical, FTC and iron methods. All seven different endophytes yielded almost all phytochemicals in methanol extracts which were tested. The endophytes A. niger, Penicillium sp. and Trichoderma sp. have shown potential in vitro antioxidant activities. Further work is needful to isolate the exact compound which is responsible for antioxidant activity and biophysical characterization will be done in the future.
文摘Fungal endophytes have been shown to improve abiotic and biotic stress response in plants. Grasses growing along the Oregon coast are exposed to harsh conditions and may harbor endophytes that enable them to survive and grow under these conditions. Endophytic fungi were isolated from thirty-four grass plants representing eight different grass species at four different locations along the Oregon coast. The ITS-1, 5.8S, and ITS-2 regions of each isolate were amplified, sequenced, and used to perform a BLAST search against the nucleotide database collection at National Center for Biotechnology Information. One-hundred-eleven different fungal isolates were classified into thirtynine genera with two isolates that did not show a match greater than 95%. These endophytes will be investigated to determine their potential for improving the adaptability of grasses and other crop plants to grow in diverse environments where they are subjected to multiple biotic and abiotic stresses.
文摘This study aims to isolate and identify taxonomic characterization of endophytic fungi from bitter melon in Guangdong province, China. A total of 1172 endophytic fungi are isolated from roots, stems, leaves, flowers, and fruits of healthy plants, and they are classified to 49 taxa based on morphological and molecular features. The results show that endophytic fungi from bitter melon plants exhibit high biodiversity. Arthrinium aureum, A. marii, A. sphaerospermum, Corynascus verrucosus, Curvularia borreriae and C. protuberate have not been recorded in any plants in China. Basidiomycetous endophytes, such as Ceratobasidium sp., and C. cornigerum, are reported in this study for the first time in bitter melon. According to the results of phylogenetic analysis, the rDNA ITS (Internal Transcribed Spacer) sequences can successfully separate species, such as F. solani, F. kyushuense, C. verrucosus, C. globosum, E. rostratum, C. brachyspora, C. verruculosus, C. affinis, P. bougainvilleicola, P. longicolla, P. glabrae, P. verruculosum, P. oxalicum, P. citrinum, P. chermesinum, P. glomerata, A. fumigatus and A. japonicas. Some isolates belonging to A. alternata, C. gloeosporioides, C. cladosporioides, C. brasiliense, C. convolutum, F. proliferatum, F. oxysporum, F. verticillioides, F. equiseti, F. camptoceras and Xylaria, however, require the analysis of others molecular markers to provide better taxonomic resolution. Molecular analyses of rDNA ITS sequences are useful for identification and classification of endophytes of bitter melon, but it is desirable to consider an integrated approach, such as molecular phylogeny, host, colony growth rate, symptoms, and shape of conidia.