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Li YY, Tan XM, Wang YD, Yang J, Zhang YG, Sun BD, Gong T, Guo LP, Ding G. Bioactive seco-Sativene Sesquiterpenoids from an Artemisia desertorum Endophytic Fungus, Cochliobolus sativus. J Nat Prod 2020; 83:1488-1494. [PMID: 32302133 DOI: 10.1021/acs.jnatprod.9b01148] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
A series of seco-sativene sesquiterpenoids (1-11) including two new natural products (2 and 3), four new analogues (4-7), and six known analogues, helminthosporic acid (1), drechslerine A (8), drechslerine B (9), helminthosporol (10), helminthosporal acid (11), and isosativenediol (12), were purified from the endophytic fungus Cochliobolus sativus isolated from a desert plant, Artemisia desertorum. The stereochemistry of helminthosporic acid (1) was established for the first time by X-ray diffraction, and the structures including relative and absolute configurations of these new compounds were determined by NMR and CD spectra together with biosynthetic considerations. Compounds 5-7 are the first seco-sativene sesquiterpenoids possessing a glucose group on C-15, C-15, and C-14, respectively. Compounds 1, 7, 9, and 11 displayed strong phytotoxic effects on corn leaves by producing visible lesions, and helminthosporic acid (1) was shown to promote division of leaves and roots of Arabidopsis thaliana with a dose-dependent relationship.
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Affiliation(s)
- Yuan-Yuan Li
- Key Laboratory of Bioactive Substances and Resources Utilization of Chinese Herbal Medicine, Ministry of Education, Institute of Medicinal Plant Development, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing 100193, People's Republic of China
| | - Xiang-Mei Tan
- Key Laboratory of Bioactive Substances and Resources Utilization of Chinese Herbal Medicine, Ministry of Education, Institute of Medicinal Plant Development, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing 100193, People's Republic of China
| | - Yan-Duo Wang
- Key Laboratory of Bioactive Substances and Resources Utilization of Chinese Herbal Medicine, Ministry of Education, Institute of Medicinal Plant Development, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing 100193, People's Republic of China
| | - Jian Yang
- National Resource Center for Chinese Materia Medica, China Academy of Chinese Medical Sciences, Beijing 100700, People's Republic of China
| | - Yong-Gang Zhang
- Biology Institute, Qilu University of Technology (Shandong Academy of Sciences), Shandong, Jinan 250103, People's Republic of China
| | - Bing-Da Sun
- Institute of Microbiology, Chinese Academy of Sciences, Beijing 100090, People's Republic of China
| | - Ting Gong
- State Key Laboratory of Bioactive Substance and Function of Natural Medicines, Institute of Materia Medica, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing 100050, People's Republic of China
| | - Lan-Ping Guo
- National Resource Center for Chinese Materia Medica, China Academy of Chinese Medical Sciences, Beijing 100700, People's Republic of China
- State Key Laboratory Breeding Base of Dao-di Herbs, Beijing 100700, People's Republic of China
| | - Gang Ding
- Key Laboratory of Bioactive Substances and Resources Utilization of Chinese Herbal Medicine, Ministry of Education, Institute of Medicinal Plant Development, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing 100193, People's Republic of China
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Shi XS, Meng LH, Li XM, Li X, Wang DJ, Li HL, Zhou XW, Wang BG. Trichocadinins B-G: Antimicrobial Cadinane Sesquiterpenes from Trichoderma virens QA-8, an Endophytic Fungus Obtained from the Medicinal Plant Artemisia argyi. J Nat Prod 2019; 82:2470-2476. [PMID: 31418264 DOI: 10.1021/acs.jnatprod.9b00139] [Citation(s) in RCA: 21] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
Trichocadinins B-G (1-6), six new cadinane-type sesquiterpene derivatives, each with C-14 carboxyl functionality, were isolated from the culture extract of Trichoderma virens QA-8, an endophytic fungus obtained from the fresh inner tissue of the medicinal plant Artemisia argyi. Their structures were elucidated by interpretation of the NMR spectroscopic and mass spectrometric data. The structures and absolute configurations of compounds 1 and 3 were confirmed by X-ray crystallographic analysis. Compounds 1-3 showed antibacterial and antifungal activity.
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Affiliation(s)
- Xiao-Shan Shi
- Key Laboratory of Experimental Marine Biology, Institute of Oceanology , Chinese Academy of Sciences, and Laboratory of Marine Biology and Biotechnology, Qingdao National Laboratory for Marine Science and Technology , Nanhai Road 7 , Qingdao 266071 , People's Republic of China
- College of Chemistry and Chemical Engineering , Hubei Normal University , Cihu Road 11 , Huangshi 435002 , People's Republic of China
- University of Chinese Academy of Sciences , Yuquan Road 19A , Beijing 100049 , People's Republic of China
| | - Ling-Hong Meng
- Key Laboratory of Experimental Marine Biology, Institute of Oceanology , Chinese Academy of Sciences, and Laboratory of Marine Biology and Biotechnology, Qingdao National Laboratory for Marine Science and Technology , Nanhai Road 7 , Qingdao 266071 , People's Republic of China
- Center for Ocean Mega-Science , Chinese Academy of Sciences , Nanhai Road 7 , Qingdao 266071 , People's Republic of China
| | - Xiao-Ming Li
- Key Laboratory of Experimental Marine Biology, Institute of Oceanology , Chinese Academy of Sciences, and Laboratory of Marine Biology and Biotechnology, Qingdao National Laboratory for Marine Science and Technology , Nanhai Road 7 , Qingdao 266071 , People's Republic of China
- Center for Ocean Mega-Science , Chinese Academy of Sciences , Nanhai Road 7 , Qingdao 266071 , People's Republic of China
| | - Xin Li
- Key Laboratory of Experimental Marine Biology, Institute of Oceanology , Chinese Academy of Sciences, and Laboratory of Marine Biology and Biotechnology, Qingdao National Laboratory for Marine Science and Technology , Nanhai Road 7 , Qingdao 266071 , People's Republic of China
- Center for Ocean Mega-Science , Chinese Academy of Sciences , Nanhai Road 7 , Qingdao 266071 , People's Republic of China
| | - Dun-Jia Wang
- College of Chemistry and Chemical Engineering , Hubei Normal University , Cihu Road 11 , Huangshi 435002 , People's Republic of China
| | - Hong-Lei Li
- Key Laboratory of Experimental Marine Biology, Institute of Oceanology , Chinese Academy of Sciences, and Laboratory of Marine Biology and Biotechnology, Qingdao National Laboratory for Marine Science and Technology , Nanhai Road 7 , Qingdao 266071 , People's Republic of China
- Center for Ocean Mega-Science , Chinese Academy of Sciences , Nanhai Road 7 , Qingdao 266071 , People's Republic of China
| | - Xing-Wang Zhou
- College of Chemistry and Chemical Engineering , Hubei Normal University , Cihu Road 11 , Huangshi 435002 , People's Republic of China
| | - Bin-Gui Wang
- Key Laboratory of Experimental Marine Biology, Institute of Oceanology , Chinese Academy of Sciences, and Laboratory of Marine Biology and Biotechnology, Qingdao National Laboratory for Marine Science and Technology , Nanhai Road 7 , Qingdao 266071 , People's Republic of China
- Center for Ocean Mega-Science , Chinese Academy of Sciences , Nanhai Road 7 , Qingdao 266071 , People's Republic of China
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Hu D, Zhang S, Baskin JM, Baskin CC, Wang Z, Liu R, Du J, Yang X, Huang Z. Seed mucilage interacts with soil microbial community and physiochemical processes to affect seedling emergence on desert sand dunes. Plant Cell Environ 2019; 42:591-605. [PMID: 30193400 DOI: 10.1111/pce.13442] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/17/2018] [Revised: 08/31/2018] [Accepted: 09/03/2018] [Indexed: 06/08/2023]
Abstract
Seedling emergence is a critical stage in the establishment of desert plants. Soil microbes participate in plant growth and development, but information is lacking with regard to the role of microbes on seedling emergence. We applied the biocides (captan and streptomycin) to assess how seed mucilage interacts with soil microbial community and physiochemical processes to affect seedling emergence of Artemisia sphaerocephala on the desert sand dune. Fungal and bacterial community composition and diversity and fungal-bacterial interactions were changed by both captan and streptomycin. Mucilage increased soil enzyme activities and fungal-bacterial interactions. Highest seedling emergence occurred under streptomycin and mucilage treatment. Members of the phyla Firmicutes and Glomeromycota were the keystone species that improved A. sphaerocephala seedling emergence, by increasing resistance of young seedlings to drought and pathogen. Seed mucilage directly improved seedling emergence and indirectly interacted with the soil microbial community through strengthening fungal-bacterial interactions and providing favourable environment for soil enzymes to affect seedling emergence. Our study provides a comprehensive understanding of the regulatory mechanisms by which soil microbial community and seed mucilage interactively promote successful establishment of populations of desert plants on the barren and stressful sand dune.
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Affiliation(s)
- Dandan Hu
- State Key Laboratory of Vegetation and Environmental Change, Institute of Botany, Chinese Academy of Sciences, Beijing, China
- University of Chinese Academy of Sciences, Beijing, China
| | - Shudong Zhang
- State Key Laboratory of Vegetation and Environmental Change, Institute of Botany, Chinese Academy of Sciences, Beijing, China
- University of Chinese Academy of Sciences, Beijing, China
| | - Jerry M Baskin
- Department of Biology, University of Kentucky, Lexington, Kentucky
| | - Carol C Baskin
- Department of Biology, University of Kentucky, Lexington, Kentucky
- Department of Plant and Soil Sciences, University of Kentucky, Lexington, Kentucky
| | - Zhaoren Wang
- State Key Laboratory of Vegetation and Environmental Change, Institute of Botany, Chinese Academy of Sciences, Beijing, China
- University of Chinese Academy of Sciences, Beijing, China
| | - Rong Liu
- State Key Laboratory of Vegetation and Environmental Change, Institute of Botany, Chinese Academy of Sciences, Beijing, China
- University of Chinese Academy of Sciences, Beijing, China
| | - Juan Du
- State Key Laboratory of Vegetation and Environmental Change, Institute of Botany, Chinese Academy of Sciences, Beijing, China
| | - Xuejun Yang
- State Key Laboratory of Vegetation and Environmental Change, Institute of Botany, Chinese Academy of Sciences, Beijing, China
| | - Zhenying Huang
- State Key Laboratory of Vegetation and Environmental Change, Institute of Botany, Chinese Academy of Sciences, Beijing, China
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Hu D, Baskin JM, Baskin CC, Wang Z, Zhang S, Yang X, Huang Z. Arbuscular mycorrhizal symbiosis and achene mucilage have independent functions in seedling growth of a desert shrub. J Plant Physiol 2019; 232:1-11. [PMID: 30530198 DOI: 10.1016/j.jplph.2018.11.010] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/29/2018] [Revised: 11/11/2018] [Accepted: 11/11/2018] [Indexed: 06/09/2023]
Abstract
Arbuscular mycorrhizal (AM) symbiosis can play a role in improving seedling establishment in deserts, and it has been suggested that achene mucilage facilitates seedling establishment in sandy deserts and that mucilage biodegradation products may improve seedling growth. We aimed to determine if AM symbiosis interacts with achene mucilage in regulating seedling growth in sand dunes. Up to 20 A M fungal taxa colonized Artemisia sphaerocephala roots in the field, and mycorrhizal frequency and colonization intensity exhibited seasonal dynamics. In the greenhouse, total biomass of AM fungal-colonized plants decreased, whereas the root/shoot ratio increased. AM symbiosis resulted in increased concentrations of nutrients and chlorophyll and decreased concentrations of salicylic acid (SA) and abscisic acid (ABA). Achene mucilage had a weaker effect on biomass and on nutrient, chlorophyll, and phytohormone concentration than did AM symbiosis. We suggest that AM symbiosis and achene mucilage act independently in enhancing seedling establishment in sandy deserts.
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Affiliation(s)
- Dandan Hu
- State Key Laboratory of Vegetation and Environmental Change, Institute of Botany, Chinese Academy of Sciences, Beijing, 100093, PR China; University of Chinese Academy of Sciences, Beijing, 100039, PR China
| | - Jerry M Baskin
- Department of Biology, University of Kentucky, Lexington, KY, 40506, USA
| | - Carol C Baskin
- Department of Biology, University of Kentucky, Lexington, KY, 40506, USA; Department of Plant and Soil Sciences, University of Kentucky, Lexington, KY, 40546, USA
| | - Zhaoren Wang
- State Key Laboratory of Vegetation and Environmental Change, Institute of Botany, Chinese Academy of Sciences, Beijing, 100093, PR China; University of Chinese Academy of Sciences, Beijing, 100039, PR China
| | - Shudong Zhang
- State Key Laboratory of Vegetation and Environmental Change, Institute of Botany, Chinese Academy of Sciences, Beijing, 100093, PR China; University of Chinese Academy of Sciences, Beijing, 100039, PR China
| | - Xuejun Yang
- State Key Laboratory of Vegetation and Environmental Change, Institute of Botany, Chinese Academy of Sciences, Beijing, 100093, PR China.
| | - Zhenying Huang
- State Key Laboratory of Vegetation and Environmental Change, Institute of Botany, Chinese Academy of Sciences, Beijing, 100093, PR China.
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Bueno de Mesquita CP, Martinez Del Río CM, Suding KN, Schmidt SK. Rapid temporal changes in root colonization by arbuscular mycorrhizal fungi and fine root endophytes, not dark septate endophytes, track plant activity and environment in an alpine ecosystem. Mycorrhiza 2018; 28:717-726. [PMID: 30141076 DOI: 10.1007/s00572-018-0863-7] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/22/2018] [Accepted: 08/17/2018] [Indexed: 05/16/2023]
Abstract
Fungal root endophytes play an important role in plant nutrition, helping plants acquire nutrients in exchange for photosynthates. We sought to characterize the progression of root colonization by arbuscular mycorrhizal fungi (AMF), dark septate endophytes (DSE), and fine root endophytes (FRE) over an alpine growing season, and to understand the role of the host plant and environment in driving colonization levels. We sampled four forbs on a regular schedule from June 26th-September 11th from a moist meadow (3535 m a.s.l) on Niwot Ridge, Rocky Mountain Front Range, CO, USA. We quantified the degree of root colonization by storage structures, exchange structures, and hyphae of all three groups of fungi. AMF and FRE percent colonization fluctuated significantly over time, while DSE did not. All AMF structures changed over time, and the degree of change in vesicles differed by plant species. FRE hyphae, AMF arbuscules and AMF vesicles peaked late in the season as plants produced seeds. AMF hyphae levels started high, decreased, and then increased within 20 days, highlighting the dynamic nature of plant-fungal interactions. Overall, our results show that AMF and FRE, not DSE, root colonization rapidly changes over the course of a growing season and these changes are driven by plant phenology and seasonal changes in the environment.
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Affiliation(s)
- Clifton P Bueno de Mesquita
- Department of Ecology and Evolutionary Biology, University of Colorado, Boulder, CO, 80309-0334, USA.
- Institute of Arctic and Alpine Research, University of Colorado, Boulder, CO, 80309-0450, USA.
| | - Cormac M Martinez Del Río
- Department of Ecology and Evolutionary Biology, University of California, Santa Cruz, CA, 95064, USA
| | - Katharine N Suding
- Department of Ecology and Evolutionary Biology, University of Colorado, Boulder, CO, 80309-0334, USA
- Institute of Arctic and Alpine Research, University of Colorado, Boulder, CO, 80309-0450, USA
| | - Steven K Schmidt
- Department of Ecology and Evolutionary Biology, University of Colorado, Boulder, CO, 80309-0334, USA
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Kodym A, Senula A, Temsch EM, Hood-Nowotny R, Schumacher F, Sekurova ON, Zotchev SB, Kiehn M. Micropropagation and Cryoconservation of the Endangered Plant Species Artemisia laciniata (Asteraceae). Cryo Letters 2018; 39:177-189. [PMID: 30059564] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 06/08/2023]
Abstract
UNLABELLED BACKGROUND: Artemisia laciniata, mainly distributed in Siberia and Central Asia, is classified as critically endangered in Europe. OBJECTIVES This study developed a protocol for its micropropagation and cryopreservation. MATERIALS AND METHODS In vitro cultures from fresh seed and in vivo shoots were initiated. Micropropagation and cryopreservation protocols were developed. Bacteria detected after cryopreservation were investigated using 16S rRNA analysis. Genome size measurements of regenerated plants after cryopreservation using flow cytometry and carbon isotope measurements to evaluate stress status were also carried out. RESULTS A. laciniata from both starting materials could be successfully propagated on MS medium with 0.5 uM BAP. Material initiated from in vivo shoots yielded lower regeneration percentages (16%) after cryopreservation than material generated from seed (57 and 63%) using the droplet-vitrification method and PVS3. Bacteria occurring after cryopreservation belonged to the genera Sphingomonas, Staphylococcus, Curtobacterium and Gordonia. There was no significant difference in the genome size and stress status between non-cryopreserved and cryopreserved plants. CONCLUSION A. laciniata could be readily micropropagated and cryopreserved. No negative effects of cryopreservation on plant water use efficiency or on genetic stability were found.
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Affiliation(s)
- A Kodym
- Department of Pharmacognosy, University of Vienna, 1090 Vienna, Austria. Core Facility Botanical Garden, University of Vienna, 1030 Vienna, Austria.
| | - A Senula
- Leibniz Institute of Plant Genetics and Crop Plant Research (IPK), 06466 Seeland OT Gatersleben, Germany
| | - E M Temsch
- Dept. of Botany and Biodiversity Research, University of Vienna, 1030 Vienna, Austria
| | - R Hood-Nowotny
- Energy Department, AIT Austrian Institute of Technology GmbH, 3430 Tulln, Austria
| | - F Schumacher
- Core Facility Botanical Garden, University of Vienna, 1030 Vienna, Austria
| | - O N Sekurova
- Department of Pharmacognosy, University of Vienna, 1090 Vienna, Austria
| | - S B Zotchev
- Department of Pharmacognosy, University of Vienna, 1090 Vienna, Austria
| | - M Kiehn
- Core Facility Botanical Garden, University of Vienna, 1030 Vienna, Austria
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Martirosyan V, Unc A, Miller G, Doniger T, Wachtel C, Steinberger Y. Desert Perennial Shrubs Shape the Microbial-Community Miscellany in Laimosphere and Phyllosphere Space. Microb Ecol 2016; 72:659-668. [PMID: 27450478 DOI: 10.1007/s00248-016-0822-9] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/25/2016] [Accepted: 07/14/2016] [Indexed: 06/06/2023]
Abstract
Microbial function, composition, and distribution play a fundamental role in ecosystem ecology. The interaction between desert plants and their associated microbes is expected to greatly affect their response to changes in this harsh environment. Using comparative analyses, we studied the impact of three desert shrubs, Atriplex halimus (A), Artemisia herba-alba (AHA), and Hammada scoparia (HS), on soil- and leaf-associated microbial communities. DNA extracted from the leaf surface and soil samples collected beneath the shrubs were used to study associated microbial diversity using a sequencing survey of variable regions of bacterial 16S rRNA and fungal ribosomal internal transcribed spacer (ITS1). We found that the composition of bacterial and fungal orders is plant-type-specific, indicating that each plant type provides a suitable and unique microenvironment. The different adaptive ecophysiological properties of the three plant species and the differential effect on their associated microbial composition point to the role of adaptation in the shaping of microbial diversity. Overall, our findings suggest a link between plant ecophysiological adaptation as a "temporary host" and the biotic-community parameters in extreme xeric environments.
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Affiliation(s)
- Varsik Martirosyan
- The Mina and Everard Goodman Faculty of Life Sciences, Bar-Ilan University, Ramat-Gan, 5290002, Israel
- Life Sciences International Postgraduate Educational Center, Acharyan 31 Str., Yerevan, 0040, Armenia
| | - Adrian Unc
- Boreal Ecosystems Research Initiative, Memorial University of Newfoundland, Corner Brook, Newfoundland and Labrador, A2H 6P9, Canada
| | - Gad Miller
- The Mina and Everard Goodman Faculty of Life Sciences, Bar-Ilan University, Ramat-Gan, 5290002, Israel
| | - Tirza Doniger
- The Mina and Everard Goodman Faculty of Life Sciences, Bar-Ilan University, Ramat-Gan, 5290002, Israel
| | - Chaim Wachtel
- The Mina and Everard Goodman Faculty of Life Sciences, Bar-Ilan University, Ramat-Gan, 5290002, Israel
| | - Yosef Steinberger
- The Mina and Everard Goodman Faculty of Life Sciences, Bar-Ilan University, Ramat-Gan, 5290002, Israel.
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Davidson BE, Novak SJ, Serpe MD. Consequences of inoculation with native arbuscular mycorrhizal fungi for root colonization and survival of Artemisia tridentata ssp. wyomingensis seedlings after transplanting. Mycorrhiza 2016; 26:595-608. [PMID: 27075898 DOI: 10.1007/s00572-016-0696-1] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/06/2016] [Accepted: 04/05/2016] [Indexed: 06/05/2023]
Abstract
In arid environments, the propagule density of arbuscular mycorrhizal fungi (AMF) may limit the extent of the plant-AMF symbiosis. Inoculation of seedlings with AMF could alleviate this problem, but the success of this practice largely depends on the ability of the inoculum to multiply and colonize the growing root system after transplanting. These phenomena were investigated in Artemisia tridentata ssp. wyomingensis (Wyoming big sagebrush) seedlings inoculated with native AMF. Seedlings were first grown in a greenhouse in soil without AMF (non-inoculated seedlings) or with AMF (inoculated seedlings). In spring and fall, 3-month-old seedlings were transplanted outdoors to 24-L pots containing soil from a sagebrush habitat (spring and fall mesocosm experiments) or to a recently burned sagebrush habitat (spring and fall field experiments). Five or 8 months after transplanting, colonization was about twofold higher in inoculated than non-inoculated seedlings, except for the spring field experiment. In the mesocosm experiments, inoculation increased survival during the summer by 24 % (p = 0.011). In the field experiments, increased AMF colonization was associated with increases in survival during cold and dry periods; 1 year after transplanting, survival of inoculated seedlings was 27 % higher than that of non-inoculated ones (p < 0.001). To investigate possible mechanisms by which AMF increased survival, we analyzed water use efficiency (WUE) based on foliar (13)C/(12)C isotope ratios (δ (13)C). A positive correlation between AMF colonization and δ (13)C values was observed in the spring mesocosm experiment. In contrast, inoculation did not affect the δ (13)C values of fall transplanted seedlings that were collected the subsequent spring. The effectiveness of AMF inoculation on enhancing colonization and reducing seedling mortality varied among the different experiments, but average effects were estimated by meta-analyses. Several months after transplanting, average AMF colonization was in proportion 84 % higher in inoculated than non-inoculated seedlings (p = 0.0042), while the average risk of seedling mortality was 42 % lower in inoculated than non-inoculated seedlings (p = 0.047). These results indicate that inoculation can increase AMF colonization over the background levels occurring in the soil, leading to higher rates of survival.
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Affiliation(s)
- Bill E Davidson
- Department of Biological Sciences, Boise State University, 1910 University Drive, Boise, ID, 83725-1515, USA
| | - Stephen J Novak
- Department of Biological Sciences, Boise State University, 1910 University Drive, Boise, ID, 83725-1515, USA
| | - Marcelo D Serpe
- Department of Biological Sciences, Boise State University, 1910 University Drive, Boise, ID, 83725-1515, USA.
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Noorashikin MN, Li LY, Karim M, Daud HM, Natrah FMI. Screening and identification of quorum sensing degraders from live feed Artemia. J Environ Biol 2016; 37:811-816. [PMID: 28779741] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
Quorum sensing (QS) is bacterial cell-to-cell communication with small signal molecules such as acyl-homoserine lactones (AHL) that control a number of phenotypes including the regulation of virulence determinants in pathogenic bacteria. Therefore, quorum sensing degrader has been suggested as one of the biocontrol strategies to fight bacterial infections. In the present study, different bacterial QS degrader strains were isolated from Artemia and screened using Chromobacterium violaceum CV026 bioassay. The results showed that six bacterial strains (four Gram-positive and two Gram-negative) isolated from Artemia were able to degrade AHL in two different in vitro assays. All the strains were later identified through 16S rRNA gene sequencing as Rhodococcus opacus, Strepsporangium roseum, Streptomyces alboniger, Enterobacter clocae and Bacillus litoralis. Highest bacterial AHL degrader, Bacillus litoralis BP-ART/6 fully degraded 10 ppm AHL in 9 hrs. The present study showed that bacterial strains isolated from Artemia can act as a QS degrader. ?
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Wiber CF, King GM, Aho K. Relative abundance of and composition within fungal orders differ between cheatgrass (Bromus tectorum) and sagebrush (Artemisia tridentata)-associated soils. PLoS One 2015; 10:e0123849. [PMID: 25822987 PMCID: PMC4378941 DOI: 10.1371/journal.pone.0123849] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
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Carter KA, Smith JF, White MM, Serpe MD. Assessing the diversity of arbuscular mycorrhizal fungi in semiarid shrublands dominated by Artemisia tridentata ssp. wyomingensis. Mycorrhiza 2014; 24:301-314. [PMID: 24249492 DOI: 10.1007/s00572-013-0537-4] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/30/2013] [Accepted: 10/27/2013] [Indexed: 06/02/2023]
Abstract
Variation in the abiotic environment and host plant preferences can affect the composition of arbuscular mycorrhizal (AMF) assemblages. This study analyzed the AMF taxa present in soil and seedlings of Artemisia tridentata ssp. wyomingensis collected from sagebrush steppe communities in southwestern Idaho, USA. Our aims were to determine the AMF diversity within and among these communities and the extent to which preferential AMF-plant associations develop during seedling establishment. Mycorrhizae were identified using molecular methods following DNA extraction from field and pot culture samples. The extracted DNA was amplified using Glomeromycota specific primers, and identification of AMF was based on phylogenetic analysis of sequences from the large subunit-D2 rDNA region. The phylogenetic analyses revealed seven phylotypes, two within the Claroideoglomeraceae and five within the Glomeraceae. Four phylotypes clustered with known species including Claroideoglomus claroideum, Rhizophagus irregularis, Glomus microaggregatum, and Funneliformis mosseae. The other three phylotypes were similar to several published sequences not included in the phylogenetic analysis, but all of these were from uncultured and unnamed glomeromycetes. Pairwise distance analysis revealed some phylotypes with high genetic variation. The most diverse was the phylotype that included R. irregularis, which contained sequences showing pairwise differences up to 12 %. Most of the diversity in AMF sequences occurred within sites. The smaller genetic differentiation detected among sites was correlated with differences in soil texture. In addition, multiplication in pot cultures led to differentiation of AMF communities. Comparison of sequences obtained from the soil with those from A. tridentata roots revealed no significant differences between the AMF present in these samples. Overall, the sites sampled were dominated by cosmopolitan AMF taxa, and young seedlings of A. tridentata ssp. wyomingensis were colonized in relation to the abundance of these taxa in the soil.
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Affiliation(s)
- Keith A Carter
- Department of Biological Sciences, Boise State University, 1910 University Drive, Boise, ID, 83725-1515, USA
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Qian YX, Kang JC, Lei BX, Wang L, Huang Y. [Screening and taxonomic identification of endophytic fungi with antitumor and antioxidant activities from Artemisia lactiflora]. Zhongguo Zhong Yao Za Zhi 2014; 39:438-441. [PMID: 24946544] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
Artemisia lactiflora is an important medicinal plant in China. The antitumor and antioxidant activities of the extracts of 54 endophytic fungi from the plant were screened via MTT assay and DPPH scavenging radical assay, respectively. The bioactive strains were identified based on similarity of 5.8S gene and internal transcribed spacer (ITS) sequences. The results showed that extracts from ten (18.5%) isolates exhibited antitumor activity, and which from two (3.7%) isolates exhibited antioxidant activity. The Alternaria sp. GYBH47 strain was simultaneously having antagonistic activity against HL-60 leukemia, MCF-7 breast and COLO205 colon cell lines, and Phomopsis sp. GYBH42 strain having cytotoxic and antioxidant activities. The results indicated that endophytic fungi from Artemisia lactiflora are potential resources to find valuable bioactive components.
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13
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Hernandez RR, Allen MF. Diurnal patterns of productivity of arbuscular mycorrhizal fungi revealed with the Soil Ecosystem Observatory. New Phytol 2013; 200:547-557. [PMID: 23844990 PMCID: PMC4288973 DOI: 10.1111/nph.12393] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/22/2013] [Accepted: 05/24/2013] [Indexed: 05/08/2023]
Abstract
Arbuscular mycorrhizal (AM) fungi are the most abundant plant symbiont and a major pathway of carbon sequestration in soils. However, their basic biology, including their activity throughout a 24-h day : night cycle, remains unknown. We employed the in situ Soil Ecosystem Observatory to quantify the rates of diurnal growth, dieback and net productivity of extra-radical AM fungi. AM fungal hyphae showed significantly different rates of growth and dieback over a period of 24 h and paralleled the circadian-driven photosynthetic oscillations observed in plants. The greatest rates (and incidences) of growth and dieback occurred between noon and 18:00 h. Growth and dieback events often occurred simultaneously and were tightly coupled with soil temperature and moisture, suggesting a rapid acclimation of the external phase of AM fungi to the immediate environment. Changes in the environmental conditions and variability of the mycorrhizosphere may alter the diurnal patterns of productivity of AM fungi, thereby modifying soil carbon sequestration, nutrient cycling and host plant success.
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Affiliation(s)
- Rebecca R Hernandez
- Department of Environmental Earth System Science, Stanford University, Stanford, CA, 94305, USA
- Department of Global Ecology, Carnegie Institution for Science, Stanford, CA, 94305, USA
- Center for Conservation Biology, University of California, Riverside, CA, 92521, USA
| | - Michael F Allen
- Center for Conservation Biology, University of California, Riverside, CA, 92521, USA
- Department of Biology, University of California, Riverside, CA, 92521, USA
- Department of Plant Pathology and Microbiology, University of California, Riverside, CA, 92521, USA
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14
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Busby RR, Stromberger ME, Rodriguez G, Gebhart DL, Paschke MW. Arbuscular mycorrhizal fungal community differs between a coexisting native shrub and introduced annual grass. Mycorrhiza 2013; 23:129-141. [PMID: 22864708 DOI: 10.1007/s00572-012-0455-x] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/07/2012] [Accepted: 07/02/2012] [Indexed: 06/01/2023]
Abstract
Arbuscular mycorrhizal fungi (AMF) have been implicated in non-native plant invasion success and persistence. However, few studies have identified the AMF species associating directly with plant invaders, or how these associations differ from those of native plant species. Identifying changes to the AMF community due to plant invasion could yield key plant-AMF interactions necessary for the restoration of native plant communities. This research compared AMF associating with coexisting Bromus tectorum, an invasive annual grass, and Artemisia tridentata, the dominant native shrub in western North America. At three sites, soil and root samples from Bromus and Artemisia were collected. Sporulation was induced using trap cultures, and spores were identified using morphological characteristics. DNA was extracted from root and soil subsamples and amplified. Sequences obtained were aligned and analyzed to compare diversity, composition, and phylogenetic distance between hosts and sites. Richness of AMF species associated with Artemisia in cultures was higher than AMF species associated with Bromus. Gamma diversity was similar and beta diversity was higher in AMF associated with Bromus compared to Artemisia. AMF community composition differed between hosts in both cultures and roots. Two AMF species (Archaeospora trappei and Viscospora viscosum) associated more frequently with Artemisia than Bromus across multiple sites. AMF communities in Bromus roots were more phylogenetically dispersed than in Artemisia roots, indicating a greater competition for resources within the invasive grass. Bromus associated with an AMF community that differed from Artemisia in a number of ways, and these changes could restrict native plant establishment.
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Affiliation(s)
- Ryan R Busby
- Graduate Degree Program in Ecology, Colorado State University, Fort Collins, CO 80523, USA.
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15
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Lin L, Ge HM, Yan T, Qin YH, Tan RX. Thaxtomin A-deficient endophytic Streptomyces sp. enhances plant disease resistance to pathogenic Streptomyces scabies. Planta 2012; 236:1849-1861. [PMID: 22922880 DOI: 10.1007/s00425-012-1741-8] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/26/2012] [Accepted: 08/06/2012] [Indexed: 06/01/2023]
Abstract
Each plant species in nature harbors endophytes, a community of microbes living within host plants without causing any disease symptom. However, the exploitation of endophyte-based phytoprotectants is hampered by the paucity of mechanistic understandings of endophyte-plant interaction. We here reported two endophytic Streptomyces isolates IFB-A02 and IFB-A03 recovered from a stress-tolerant dicotyledonous plant Artemisia annua L. After the determination of their non-pathogenicity at the genomic level and from the toxin (thaxtomin A, TXT) level, the endophytism of both isolates was supported by their successful colonization in planta. Of the two endophytes, IFB-A03 was further studied for the mechanism of endophyte-conferred phytoprotection owing to its plant growth promotion in model eudicot Arabidopsis thaliana. Using the endophyte-Arabidopsis co-cultivation system into which pathogenic Streptomyces scabies was introduced, we demonstrated that IFB-A03 pre-inoculation could activate the salicylic acid (SA)-mediated plant defense responses upon pathogen challenge. Moreover, IFB-A03 was shown to partially rescue the defense deficiency in eds5 (enhanced disease susceptibility 5) Arabidopsis mutants, putatively acting at the upstream of SA accumulation in the defense signaling pathway associated with the systemic acquired resistance (SAR). These data suggest that endophytic Streptomyces sp. IFB-A03 could be a promising candidate for biocontrol agents against S. scabies--a causative pathogen of common scab diseases prevailing in agronomic systems.
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Affiliation(s)
- Lan Lin
- Institute of Functional Biomolecules, State Key Laboratory of Pharmaceutical Biotechnology, Nanjing University, Nanjing, 210093, People's Republic of China.
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16
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Yang X, Baskin CC, Baskin JM, Zhang W, Huang Z. Degradation of seed mucilage by soil microflora promotes early seedling growth of a desert sand dune plant. Plant Cell Environ 2012; 35:872-83. [PMID: 22070663 DOI: 10.1111/j.1365-3040.2011.02459.x] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/09/2023]
Abstract
In contrast to the extensive understanding of seed mucilage biosynthesis, much less is known about how mucilage is biodegraded and what role it plays in the soil where seeds germinate. We studied seed mucilage biodegradation by a natural microbial community. High-performance anion-exchange chromatography (HPAEC) was used to determine monosaccharide composition in achene mucilage of Artemisia sphaerocephala. Mucilage degradation by the soil microbial community from natural habitats was examined by monosaccharide utilization tests using Biolog plates, chemical assays and phospholipid fatty acid (PLFA) analysis. Glucose (29.4%), mannose (20.3%) and arabinose (19.5%) were found to be the main components of achene mucilage. The mucilage was biodegraded to CO(2) and soluble sugars, and an increase in soil microbial biomass was observed during biodegradation. Fluorescence microscopy showed the presence of mucilage (or its derivatives) in seedling tissues after growth with fluorescein isothiocyanate (FITC)-labelled mucilage. The biodegradation also promoted early seedling growth in barren sand dunes, which was associated with a large soil microbial community that supplies substances promoting seedling establishment. We conclude that biodegradation of seed mucilage can play an ecologically important role in the life cycles of plants especially in harsh desert environments to which A. sphaerocephala is well-adapted.
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Affiliation(s)
- Xuejun Yang
- State Key Laboratory of Vegetation and Environmental Change, Institute of Botany, Chinese Academy of Sciences, Beijing 100093, China
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17
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Binet MN, van Tuinen D, Deprêtre N, Koszela N, Chambon C, Gianinazzi S. Arbuscular mycorrhizal fungi associated with Artemisia umbelliformis Lam, an endangered aromatic species in Southern French Alps, influence plant P and essential oil contents. Mycorrhiza 2011; 21:523-535. [PMID: 21243378 DOI: 10.1007/s00572-010-0354-y] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/11/2010] [Accepted: 12/16/2010] [Indexed: 05/14/2023]
Abstract
Root colonization by arbuscular mycorrhizal (AM) fungi of Artemisia umbelliformis, investigated in natural and cultivated sites in the Southern Alps of France, showed typical structures (arbuscules, vesicles, hyphae) as well as spores and mycelia in its rhizosphere. Several native AM fungi belonging to different Glomeromycota genera were identified as colonizers of A. umbelliformis roots, including Glomus tenue, Glomus intraradices, G. claroideum/etunicatum and a new Acaulospora species. The use of the highly mycorrhizal species Trifolium pratense as a companion plant impacted positively on mycorrhizal colonization of A. umbelliformis under greenhouse conditions. The symbiotic performance of an alpine microbial community including native AM fungi used as inoculum on A. umbelliformis was evaluated in greenhouse conditions by comparison with mycorrhizal responses of two other alpine Artemisia species, Artemisia glacialis and Artemisia genipi Weber. Contrary to A. genipi Weber, both A. umbelliformis and A. glacialis showed a significant increase of P concentration in shoots. Volatile components were analyzed by GC-MS in shoots of A. umbelliformis 6 months after inoculation. The alpine microbial inoculum increased significantly the percentage of E-β-ocimene and reduced those of E-2-decenal and (E,E)-2-4-decadienal indicating an influence of alpine microbial inoculum on essential oil production. This work provides practical indications for the use of native AM fungi for A. umbelliformis field culture.
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Affiliation(s)
- Marie-Noëlle Binet
- UMR INRA 1088/CNRS 5184/Université Bourgogne, Plante-Microbe-Environnement, INRA-CMSE, 17 rue Sully, BP 86510, 21065, Dijon Cedex, France.
| | - Diederik van Tuinen
- UMR INRA 1088/CNRS 5184/Université Bourgogne, Plante-Microbe-Environnement, INRA-CMSE, 17 rue Sully, BP 86510, 21065, Dijon Cedex, France
| | - Nicolas Deprêtre
- Centre des Sciences du Goût et de l'Alimentation, INRA, 17 Rue Sully, 21000, Dijon, France
| | - Nathalie Koszela
- UMR INRA 1088/CNRS 5184/Université Bourgogne, Plante-Microbe-Environnement, INRA-CMSE, 17 rue Sully, BP 86510, 21065, Dijon Cedex, France
| | - Catherine Chambon
- Centre de Recherche en Biotechnologie Végétale, CERBIOTECH, 117 Route de Veynes, 05000, Gap, France
| | - Silvio Gianinazzi
- UMR INRA 1088/CNRS 5184/Université Bourgogne, Plante-Microbe-Environnement, INRA-CMSE, 17 rue Sully, BP 86510, 21065, Dijon Cedex, France
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18
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Igarashi Y, Mogi T, Yanase S, Miyanaga S, Fujita T, Sakurai H, Saiki I, Ohsaki A. Brartemicin, an inhibitor of tumor cell invasion from the actinomycete Nonomuraea sp. J Nat Prod 2009; 72:980-2. [PMID: 19358565 DOI: 10.1021/np9000575] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/15/2023]
Abstract
Brartemicin (1), a new trehalose-derived metabolite, was isolated from the culture broth of the actinomycete of the genus Nonomuraea. Its structure and absolute configuration were determined by spectroscopic analyses. The new compound inhibited the invasion of murine colon carcinoma 26-L5 cells with an IC(50) value of 0.39 microM in a concentration-dependent manner without showing cytotoxic effects.
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Affiliation(s)
- Yasuhiro Igarashi
- Biotechnology Research Center, Toyama Prefectural University, 5180 Kurokawa, Imizu, Toyama 939-0398, Japan.
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19
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Jiménez-Esquilín AE, Roane TM. Antifungal activities of actinomycete strains associated with high-altitude sagebrush rhizosphere. J Ind Microbiol Biotechnol 2005; 32:378-81. [PMID: 16044290 DOI: 10.1007/s10295-005-0007-x] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2005] [Accepted: 06/19/2005] [Indexed: 10/25/2022]
Abstract
The antifungal-producing potential of actinomycete populations from the rhizosphere of low-altitude sagebrush, Artemisia tridentata, has been examined. In a continued investigation of new sources of antifungal-producing microorganisms, this study examined the antifungal-producing potential of actinomycetes from the rhizosphere of high-altitude A. tridentata. With high-altitude sagebrush, rhizosphere soil actinomycete numbers were one to four orders of magnitude higher than those found in nonrhizosphere bulk soils and different from those found with the low-altitude plants. A total of 122 actinomycete isolates was screened against nine fungal species and six bacterial species for the production of antimicrobial compounds. Four rhizosphere isolates, Streptomyces amakusaensis, S. coeruleorubidus, S. hawaiiensis and S. scabies, showed broad-spectrum antifungal activity against three or more fungal species in plate assays. In liquid antagonism assays, mycelium production by Aspergillus niger was reduced by up to 50% by two of the actinomycete isolates. These results demonstrate the potential of rhizosphere microbiology in the search for new antimicrobials.
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Affiliation(s)
- A E Jiménez-Esquilín
- Department of Biology, University of Colorado, Campus Box 171, Denver, CO 80217-3364, USA
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20
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Blanke V, Renker C, Wagner M, Füllner K, Held M, Kuhn AJ, Buscot F. Nitrogen supply affects arbuscular mycorrhizal colonization of Artemisia vulgaris in a phosphate-polluted field site. New Phytol 2005; 166:981-92. [PMID: 15869657 DOI: 10.1111/j.1469-8137.2005.01374.x] [Citation(s) in RCA: 52] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/02/2023]
Abstract
Root colonization by arbuscular mycorrhizal fungi (AMF) was investigated in industrially polluted grassland characterized by exceptionally high phosphorus levels (up to 120 g kg(-1) soil). Along a pollution-induced nitrogen gradient, soil and tissue element concentrations of Artemisia vulgaris plants and their mycorrhizal status were determined. Additionally, we compared mycorrhization rates and above-ground biomass of A. vulgaris at N-fertilized and control plots in the N-poor area. Despite high soil and tissue P concentrations, plants from N-deficient plots, which were characterized by low tissue N concentrations and N : P ratios, were strongly colonized by AMF, whereas at a plot with comparable P levels, but higher soil and plant N concentrations and N : P ratios, mycorrhization rates were significantly lower. Correlation analyses revealed a negative relationship between percentage root colonization of A. vulgaris by AMF and both tissue N concentration and N : P ratio. Accordingly, in the fertilization experiment, control plants had higher mycorrhization rates than N-fertilized plants, whereas the species attained higher biomass at N-fertilized plots. The results suggest that N deficiency stimulates root colonization by AMF in this extraordinarily P-rich field site.
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Affiliation(s)
- Verena Blanke
- Friedrich-Schiller-University of Jena, Institute of Ecology, Jena, Germany.
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21
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Basil AJ, Strap JL, Knotek-Smith HM, Crawford DL. Studies on the microbial populations of the rhizosphere of big sagebrush (Artemisia tridentata). J Ind Microbiol Biotechnol 2004; 31:278-88. [PMID: 15221668 DOI: 10.1007/s10295-004-0140-y] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2003] [Accepted: 04/12/2004] [Indexed: 10/26/2022]
Abstract
Prolonged use of broad-spectrum antibiotics has led to the emergence of drug-resistant pathogens, both in medicine and in agriculture. New threats such as biological warfare have increased the need for novel and efficacious antimicrobial agents. Natural habitats not previously examined as sources of novel antibiotic-producing microorganisms still exist. One such habitat is the rhizosphere of desert shrubs. Here, we show that one desert shrub habitat, the rhizosphere of desert big sagebrush ( Artemisia tridentata) is a source of actinomycetes capable of producing an extensive array of antifungal metabolites. Culturable microbial populations from both the sagebrush rhizosphere and nearby bulk soils from three different sites were enumerated and compared, using traditional plate-count techniques and antibiotic activity bioassays. There were no statistical differences between the relative numbers of culturable non-actinomycete eubacteria, actinomycetes and fungi in the rhizosphere versus bulk soils, but PCR amplification of the 16S rRNA gene sequences of the total soil DNA and denaturing gradient gel electrophoresis showed that the community structure was different between the rhizosphere and the bulk soils. A high percentage of actinomycetes produced antimicrobials; and the percentage of active producers was significantly higher among the rhizosphere isolates, as compared with the bulk soil isolates. Also, the rhizosphere strains were more active in the production of antifungal compounds than antibacterial compounds. 16S rRNA gene sequence analysis showed that sagebrush rhizospheres contained a variety of Streptomyces species possessing broad spectrum antifungal activity. Scanning electron microscopy studies of sagebrush root colonization by one of the novel sagebrush rhizosphere isolates, Streptomyces sp. strain RG, showed that it aggressively colonized young sagebrush roots, whereas another plant rhizosphere-colonizing strain, S. lydicus WYEC108, not originally isolated from sagebrush, was a poor colonizer of the roots of this plant, as were two other Streptomyces isolates from forest soil. These results support the hypothesis that the rhizosphere of desert big sagebrush is a promising source of habitat-adapted actinomycetes, producing antifungal antibiotics.
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Affiliation(s)
- Antony J Basil
- Department of Microbiology, Molecular Biology and Biochemistry, University of Idaho, Moscow, ID 83844-3052, USA
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22
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Gonzalez-Franco AC, Deobald LA, Spivak A, Crawford DL. Actinobacterial chitinase-like enzymes: profiles of rhizosphere versus non-rhizosphere isolates. Can J Microbiol 2003; 49:683-98. [PMID: 14735218 DOI: 10.1139/w03-089] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
The objective of this study was to determine if antifungal actinomycetes isolated from rhizosphere and non-rhizosphere soils exhibit different chitinase-like production and (or) induction patterns. Selected isolates from both habitats were compared. Chitinase-like levels and isoform characteristic patterns were evaluated over time in culture fluids of isolates grown on media containing different combinations of colloidal chitin and fungal cell wall (FCW) preparation. Supernatants were also subjected to native and non-native polyacrylamide gel electrophoresis (PAGE), using glycol chitin amended gels. For non-native PAGE, protein samples were denatured by two different approaches. Multiple active bands, ranging from 20 to 53 kDa and present in varying amounts, were detected in gels for most strains. Different substrate preferences were observed among strains, and different chitinase-like enzymes were produced, depending upon the substrate combinations used. The presence of FCW in the medium induced specific chitinase-like enzymes not observed otherwise. Enzymatic activities and profiles of the isolates, however, were strain and substrate specific rather than habitat specific. However, a sagebrush rhizosphere soil had a larger actinomycete community with higher chitinolytic activities than the nearby bulk soil. The use of PAGE to compare chitinase-like proteins induced in media with and without FCW was useful for identifying chitinase-like enzymes potentially involved in antifungal activity.Key words: chitinase, actinomycetes, hydrolytic enzymes, rhizosphere, antifungal.
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Affiliation(s)
- Ana C Gonzalez-Franco
- Department of Microbiology, Molecular Biology and Biochemistry, University of Idaho, Moscow 83844-3052, USA
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23
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Feige GB, Ale-Agha N, Dachowski M, Kricke R. Surveys of microfungi in a former industrial area in Duisburg-Nord. Meded Rijksuniv Gent Fak Landbouwkd Toegep Biol Wet 2003; 67:227-39. [PMID: 12701427] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 03/01/2023]
Abstract
One hundred and forty microfungi (Ascomycetes and Deuteromycetes) were collected in the "Landschaftspark Duisburg-Nord" located in North Rhine-Westphalia. New hosts for rarely found fungi are recorded for the first time. New for Germany are Massaria inquinans (Tode) De Not. and Nitschkia grevillei (Rhem) Nannf. on Acer pseudoplatanus L., Pirottaea nigrostriata Graddon on Artemisia vulgaris L., Ceratopycnis clematidis Höhn. on Clematis vitalba L., Dasyscyphus aff. humuli (W. Phillips) Dennis on Humulus lupulus L. and Leptosphaeria derasa (Berk. & Br.) Auersw. on Senecio inaequidens DC. New for North Rhine-Westphalia are Chaetosphaerella phaeostroma (Durieu & Mont.) E. Müller & Booth and Phomopsis platanoides (Cooke) Died. on Acer pseudoplatanus L., Microsphaeropsis pseudaspera Sutton, Mycosphaerella osborniae D. Hawksw. & Sivan. and Phomopsis oblita Sacc. on Artemisia vulgaris L., Leptosphaeria acuta (Fr.) P. Karst. and Leptosphaeria doliolum (Pers.) Ces. & De Not. on Bryonia dioica Jacq., Ophiobolus erythrosporus (Riess) G. Winter and Pleospora herbarum (Pers.) Rabenh. ex Ces. & De Not. on Dipsacus sylvestris (Huds), Keissleriella ocellata (Niessl) Bose on Hypericum perforatum L., Dactylaria aff. graminicola on Lolium perenne L., Siroplacodium aff. atrum on Oenothera beinnis L., Diatrypella favacea (Fr.) Sacc. on Prunus spec., Hapalosphaeria deformans (Syd.) Syd. and Microdiscula rubicola (Bres.) Höhn. on Rubus fructicosus agg. L., Cryptodiaporthe salicina (Pers.) Wehm. on Salix alba L. and Pleurophoma pleurospora (Sacc.) Höhn. on Salix caprea L.
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Affiliation(s)
- G B Feige
- Universität Essen, FB 9 Botanik Universitätsstr. 5, D-45117 Essen, Germany
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24
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Abstract
A central component in understanding plant-enemy interactions is to determine whether plant enemies, such as herbivores and pathogens, mediate the evolution of plant secondary metabolites. Using 26 populations of a broadly distributed plant species, sagebrush (Artemisia tridentata), we examined whether sagebrush populations in habitats with a greater prevalence of fungi contained antifungal secondary metabolites on leaf surfaces that were more active and diverse than sagebrush populations in habitats less favorable to fungi. Because moisture and temperature play a key role in the epidemiology of most plant-pathogen interactions, we also examined the relationship between the antifungal activity of secondary metabolites and the climate of a site. We evaluated the antifungal activity of sagebrush secondary metabolites against two fungi, a wild Penicillium sp. and a laboratory yeast, Saccharomyces cerevisiae, using a filter-paper disk assay and bioautography. Comparing the 26 sagebrush populations, we found that fungal abundance was a good predictor of both the activity (r2 = 0.36 for Saccharomyces, r2 = 0.37 for Penicillium) and number (r2 = 0.34 for Saccharomyces) of antifungal secondary metabolites. This suggests that selection imposed by fungal pathogens has led to more effective antifungal secondary metabolites. We found that the antifungal activity of sagebrush secondary metabolites was negatively related to average vapor pressure deficit of the habitat (r2 = 0.60 for Saccharomyces, r2 = 0.61 for Penicillium). Differences in antifungal activity among populations were not due to the amount of secondary metabolites, but rather to qualitative differences in the composition of antifungal compounds. Although all populations in habitats with high fungal prevalence had secondary metabolites with high antifungal activity, different suites of compounds were responsible for this activity, suggesting independent outcomes of selection on plants by fungal pathogens. The location of antifungal secondary metabolites on the leaf surface is consistent with their putative defense role, and we found no evidence supporting other functions, such as protection from ultraviolet light or oxidation. That the antifungal activity of sagebrush secondary metabolites was similar for two different fungi provides support for broad antifungal defenses. The incidence and severity of fungal disease in the field (caused by Puccinia tanaceti) were similar in moist and dry habitats, possibly reflecting an equilibrium between plant defense and fungal attack, as sites with greater fungal abundance compensated with more effective secondary metabolites. The geographic correlation between fungal abundance and antifungal secondary metabolites of sagebrush, coupled with our other data showing heritable variation in these metabolites, suggests that pathogenic fungi have selected for antifungal secondary metabolites in sagebrush.
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Affiliation(s)
- Sharon M Talley
- Department of Biology, University of Utah, 257 South 1400 East, Salt Lake City, Utah 84112-840, USA
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25
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Battikhi MNG. Characterization of a coryneform isolate from fasciated mugwort (Artemisia vulgaris). New Microbiol 2002; 25:187-93. [PMID: 12019725] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/25/2023]
Abstract
The morphological and physiological features of coryneform isolated from fasciated mugwort (Artemisia vulgaris) display many morphological similarities with the plant pathogenic corynebacteria, but differ from Corynebacterium fascians in exhibiting motility albeit in only a small proportion of each cell population, and by its ability to hydrolyze asculin, its failure to produce urease and differences in pigmentation. The isolate appears to be related to Corynebacterium fascians in its ability to cause fasciation but physiologically and biochemically it resembles Cornyebacterium poinsettiae and C. flaccumfaciens, both of which were transferred to the genus Curtobacterium.
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Affiliation(s)
- M N G Battikhi
- Hashemite University, Faculty of Allied Health Sciences, Department of Medical Laboratory Sciences, Zarqa, Jordan
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26
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Abstract
Artemisia annua, well recognized for its production of antimalarial drug artemisinin, is seldom attacked by any of phytopathogenic fungi, which could be partially associated with the presence of endophytes. Present investigation is aiming at disclosing whether the endophytes inside A. annua produce antifungal substances. A total of 39 endophytes were isolated and fermented, and the ferment broth was evaluated in vitro for the antifungal activity against crop-threatening fungi Gaeumannomyces graminis var. tritici, Rhizoctonia cerealis, Helminthosporium sativum, Fusarium graminearum, Gerlachia nivalis and Phytophthora capsici. These plant pathogens are still causing wheat take-all, sharp eyespot, common rot, scab, snow mould, and pepper phytophthora blight, respectively. Out of 39 endophytes investigated, 21 can produce in vitro substances that are inhibitory to all or a few of the tested phytopathogens whereas the rest yielded nothing active. Moreover, the most active broth of endophyte IV403 was extracted with EtOAc and n-butanol, and comparisons of the antifungal activity of the extracts indicated that the major active metabolites were EtOAc-extractable.
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Affiliation(s)
- C H Liu
- Institute of Functional Biomolecule, School of Life Sciences, Nanjing University, 210093, Nanjing, People's Republic of China
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27
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Zou WX, Meng JC, Lu H, Chen GX, Shi GX, Zhang TY, Tan RX. Metabolites of Colletotrichum gloeosporioides, an endophytic fungus in Artemisia mongolica. J Nat Prod 2000; 63:1529-1530. [PMID: 11087599 DOI: 10.1021/np000204t] [Citation(s) in RCA: 92] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
A new antimicrobial metabolite, named colletotric acid (1), was isolated from a liquid culture of Colletotrichum gloeosporioides, an endophytic fungus colonized inside the stem of Artemisia mongolica. The structure was determined using spectroscopic methods (EIMS and FABMS,(1)H and (13)C NMR, (1)H-(1)H COSY, HMBC, and HMQC). Compound 1 inhibited the growth of Bacillus subtilis, Staphylococcusaureus, and Sarcina lutea with minimal inhibitory concentrations (MICs) of 25, 50, and 50 microg/mL, respectively, and the crop pathogenic fungus Helminthosporium sativum (MIC: 50 microg/mL).
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Affiliation(s)
- W X Zou
- Institute of Functional Biomolecule, State Key Laboratory of Pharmaceutical Biotechnology, School of Life Sciences, Nanjing University, Nanjing 210093, People's Republic of China
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28
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Abstract
The level of toxigenic moulds and mycotoxins were analyzed in 62 samples of medicinal plant material and 11 herbal tea samples. The most predominant fungi detected were: Aspergillus, Penicillium, Mucor, Rhizopus, Absidia, Alternaria, Cladosporium and Trichoderma. Aspergillus flavus, a known producer of the aflatoxin mycotoxin, was present in 11 or 18% of the 62 medicinal plant samples and in 1 or 9% of the herbal tea samples. The medicinal plant samples, contaminated with A. flavus were also analyzed for the mycotoxins aflatoxin, ochratoxin and zearalenone; ochratoxin was found in one of the 7 samples analyzed. This study suggests that medicinal plant material and possibly herbal teas, if stored improperly allowing for mould growth, should be analyzed for mould and mycotoxin prior to use.
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Affiliation(s)
- M Halt
- Faculty of Food Technology, Osijek, Croatia
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