Fungal endophytes of the obligate parasitic dwarf mistletoe Arceuthobium americanum (Santalaceae) act antagonistically in vitro against the native fungal pathogen Cladosporium (Davidiellaceae) of their host

2012 ◽  
Vol 99 (12) ◽  
pp. 2027-2034 ◽  
Author(s):  
Lyssa L. Martin ◽  
Cynthia M. Ross Friedman ◽  
Lori A. Phillips
Keyword(s):  
Fungal Pathogen ◽  
Fungal Endophytes ◽  
Dwarf Mistletoe ◽  
Arceuthobium Americanum

scholarly journals Callus Culture of Arceuthobium americanum Nutt. ex Englem. and Explant Response to Varying Auxin and Cytokinin Concentrations

2012 ◽  
Vol 21 (1) ◽  
pp. 1-10 ◽  
Author(s):  
Lyssa L. Martin ◽  
Cynthia Ross Friedman ◽  
Ronald G. Smith
Keyword(s):  
North America ◽  
Callus Culture ◽  
Shoot Organogenesis ◽  
Coniferous Forests ◽  
Western North America ◽  
Laboratory Studies ◽  
Dwarf Mistletoe ◽  
Arceuthobium Americanum ◽  
Infected Area

The lodgepole pine dwarf mistletoe Arceuthobium americanum is a severe pest in coniferous forests of western North America.  To facilitate laboratory studies of this obligate parasite, a modified White’s medium was used for in vitro culture; the concentrations of IAA and Kn were varied to determine optimal IAA/Kn ratios.  It was found that explant health was related to the concentration of IAA (p = 0.008), but not Kn (p = 0.937), and that explants were healthiest at an IAA/Kn ratio of 0.1.  Radicular apices were generated at IAA/Kn ratios of 1.0 or greater, but no shoot organogenesis was observed.  These data suggest that A. americanum is more sensitive to auxins than cytokinins.  Parasites of plants are known to secrete high levels of cytokinins, which stimulate the host to shuttle nutrients to the infected area, and so we suspect that A. americanum has reduced cytokinin sensitivity.   Key words: Callus culture, Arceuthobium americanum, Explant, Response, Cytokinin, Insensitivity   D.O.I. 10.3329/ptcb.v21i1.9557   Plant Tissue Cult. & Biotech. 21(1): 1-10, 2011 (June)

Germination of pollen of the dwarf mistletoe Arceuthobium americanum

1991 ◽  
Vol 69 (3) ◽  
pp. 685-688 ◽  
Author(s):  
Jeannie Gilbert ◽  
David Punter
Keyword(s):  
Key Words ◽  
Pollen Germination ◽  
Pinus Banksiana ◽  
Optimum Temperature ◽  
Dwarf Mistletoe ◽  
In Vitro Pollen Germination ◽  
Arceuthobium Americanum ◽  
Pollen Germinability ◽  
Germination Of Pollen

Pollen of Arceuthobium americanum Nuttall ex Engelmann, a parasitic dwarf mistletoe of Pinus banksiana Lamb, in Manitoba, was germinated on media containing a range of concentrations of sucrose and salts. Highest germination levels occurred on 20% sucrose agar; addition of salts significantly depressed germination. Pollen germinability was below 5% at first but increased to near 50% as the season advanced. Mean germination differed significantly between flowers from 10 staminate plants but peaked at approximately the same times in association with increasing temperatures. Freezing night temperatures were followed by reduced germinability. The optimum temperature for in vitro pollen germination is close to 30 °C, whereas 40 °C impairs germination. Key words: parasitic angiosperms, microclimate, jack pine, reproductive biology.

Evaluating the in vitro antituberculosis, antibacterial and antioxidant potential of fungal endophytes isolated from Glycyrrhiza glabra L.

2016 ◽  
Vol 5 (2) ◽  
pp. 140-146 ◽  
Author(s):  
Aiyatullah Shah ◽  
Muzafar Ahmad Rather ◽  
Aabid Manzoor Shah ◽  
Saleem Mushtaq ◽  
Aehtesham Hussain ◽  
...  
Keyword(s):  
Fungal Endophytes ◽  
Glycyrrhiza Glabra ◽  
Antioxidant Potential ◽  
Glycyrrhiza Glabra L

scholarly journals The Influence of the Grapevine Bacterial and Fungal Endophytes on Biomass Accumulation and Stilbene Production by the In Vitro Cultivated Cells of Vitis amurensis Rupr.

Plants ◽  
2021 ◽  
Vol 10 (7) ◽  
pp. 1276
Author(s):  
Olga A. Aleynova ◽  
Andrey R. Suprun ◽  
Nikolay N. Nityagovsky ◽  
Alexandra S. Dubrovina ◽  
Konstantin V. Kiselev
Keyword(s):  
Cell Culture ◽  
Cell Suspension ◽  
Endophytic Fungi ◽  
Endophytic Bacteria ◽  
Fungal Endophytes ◽  
Biomass Accumulation ◽  
Vitis Amurensis ◽  
Grape Cell ◽  
Stilbene Biosynthesis

Plant endophytes are known to alter the profile of secondary metabolites in plant hosts. In this study, we identified the main bacterial and fungal representatives of the wild grape Vitis amurensis Rupr. microbiome and investigated a cocultivation effect of the 14 endophytes and the V. amurensis cell suspension on biomass accumulation and stilbene biosynthesis. The cocultivation of the V. amurensis cell culture with the bacteria Agrobacterium sp., Bacillus sp., and Curtobacterium sp. for 2 weeks did not significantly affect the accumulation of cell culture fresh biomass. However, it was significantly inhibited by the bacteria Erwinia sp., Pantoea sp., Pseudomonas sp., and Xanthomonas sp. and fungi Alternaria sp., Biscogniauxia sp., Cladosporium sp., Didymella sp. 2, and Fusarium sp. Cocultivation of the grapevine cell suspension with the fungi Didymella sp. 1 and Trichoderma sp. resulted in cell death. The addition of endophytic bacteria increased the total stilbene content by 2.2–5.3 times, while the addition of endophytic fungi was more effective in inducing stilbene accumulation by 2.6–16.3 times. The highest content of stilbenes in the grapevine cells cocultured with endophytic fungi was 13.63 and 13.76 mg/g of the cell dry weight (DW) after cultivation with Biscogniauxia sp. and Didymella sp. 2, respectively. The highest content of stilbenes in the grapevine cells cocultured with endophytic bacteria was 4.49 mg/g DW after cultivation with Xanthomonas sp. The increase in stilbene production was due to a significant activation of phenylalanine ammonia lyase (PAL) and stilbene synthase (STS) gene expression. We also analyzed the sensitivity of the selected endophytes to eight antibiotics, fluconazole, and trans-resveratrol. The endophytic bacteria were sensitive to gentamicin and kanamycin, while all selected fungal strains were resistant to fluconazole with the exception of Cladosporium sp. All endophytes were tolerant of trans-resveratrol. This study showed that grape endophytes stimulate the production of stilbenes in grape cell suspension, which could further contribute to the generation of a new stimulator of stilbene biosynthesis in grapevine or grape cell cultures.

scholarly journals Trojan Horse Transit Contributes to Blood-Brain Barrier Crossing of a Eukaryotic Pathogen

mBio ◽  
2017 ◽  
Vol 8 (1) ◽  
Author(s):  
Felipe H. Santiago-Tirado ◽  
Michael D. Onken ◽  
John A. Cooper ◽  
Robyn S. Klein ◽  
Tamara L. Doering
Keyword(s):  
Experimental Evidence ◽  
Cryptococcus Neoformans ◽  
Blood Brain Barrier ◽  
Fungal Pathogen ◽  
Trojan Horse ◽  
Brain Barrier ◽  
Barrier Crossing ◽  
Blood Brain ◽  
The Brain

ABSTRACT The blood-brain barrier (BBB) protects the central nervous system (CNS) by restricting the passage of molecules and microorganisms. Despite this barrier, however, the fungal pathogen Cryptococcus neoformans invades the brain, causing a meningoencephalitis that is estimated to kill over 600,000 people annually. Cryptococcal infection begins in the lung, and experimental evidence suggests that host phagocytes play a role in subsequent dissemination, although this role remains ill defined. Additionally, the disparate experimental approaches that have been used to probe various potential routes of BBB transit make it impossible to assess their relative contributions, confounding any integrated understanding of cryptococcal brain entry. Here we used an in vitro model BBB to show that a “Trojan horse” mechanism contributes significantly to fungal barrier crossing and that host factors regulate this process independently of free fungal transit. We also, for the first time, directly imaged C. neoformans-containing phagocytes crossing the BBB, showing that they do so via transendothelial pores. Finally, we found that Trojan horse crossing enables CNS entry of fungal mutants that cannot otherwise traverse the BBB, and we demonstrate additional intercellular interactions that may contribute to brain entry. Our work elucidates the mechanism of cryptococcal brain invasion and offers approaches to study other neuropathogens. IMPORTANCE The fungal pathogen Cryptococcus neoformans invades the brain, causing a meningoencephalitis that kills hundreds of thousands of people each year. One route that has been proposed for this brain entry is a Trojan horse mechanism, whereby the fungus crosses the blood-brain barrier (BBB) as a passenger inside host phagocytes. Although indirect experimental evidence supports this intriguing mechanism, it has never been directly visualized. Here we directly image Trojan horse transit and show that it is regulated independently of free fungal entry, contributes to cryptococcal BBB crossing, and allows mutant fungi that cannot enter alone to invade the brain. IMPORTANCE The fungal pathogen Cryptococcus neoformans invades the brain, causing a meningoencephalitis that kills hundreds of thousands of people each year. One route that has been proposed for this brain entry is a Trojan horse mechanism, whereby the fungus crosses the blood-brain barrier (BBB) as a passenger inside host phagocytes. Although indirect experimental evidence supports this intriguing mechanism, it has never been directly visualized. Here we directly image Trojan horse transit and show that it is regulated independently of free fungal entry, contributes to cryptococcal BBB crossing, and allows mutant fungi that cannot enter alone to invade the brain.

scholarly journals Cork Oak Endophytic Fungi as Potential Biocontrol Agents against Biscogniauxia mediterranea and Diplodia corticola

2020 ◽  
Vol 6 (4) ◽  
pp. 287
Author(s):  
Daniela Costa ◽  
Rui M. Tavares ◽  
Paula Baptista ◽  
Teresa Lino-Neto
Keyword(s):  
Fungal Endophytes ◽  
Cork Oak ◽  
In Vivo Assays ◽  
Oak Trees ◽  
Treatment Measures ◽  
Dual Plate ◽  
Antagonistic Potential ◽  
Selection Of

An increase in cork oak diseases caused by Biscogniauxia mediterranea and Diplodia corticola has been reported in the last decade. Due to the high socio-economic and ecologic importance of this plant species in the Mediterranean Basin, the search for preventive or treatment measures to control these diseases is an urgent need. Fungal endophytes were recovered from cork oak trees with different disease severity levels, using culture-dependent methods. The results showed a higher number of potential pathogens than beneficial fungi such as cork oak endophytes, even in healthy plants. The antagonist potential of a selection of eight cork oak fungal endophytes was tested against B. mediterranea and D. corticola by dual-plate assays. The tested endophytes were more efficient in inhibiting D. corticola than B. mediterranea growth, but Simplicillium aogashimaense, Fimetariella rabenhorstii, Chaetomium sp. and Alternaria alternata revealed a high potential to inhibit the growth of both. Simplicillium aogashimaense caused macroscopic and microscopic mycelial/hyphal deformations and presented promising results in controlling both phytopathogens’ growth in vitro. The evaluation of the antagonistic potential of non-volatile and volatile compounds also revealed that A. alternata compounds could be further explored for inhibiting both pathogens. These findings provide valuable knowledge that can be further explored in in vivo assays to find a suitable biocontrol agent for these cork oak diseases.

ITS2 ribotyping, in vitro anti-inflammatory screening, and metabolic profiling of fungal endophytes from the Mexican species Crescentia alata Kunth

2020 ◽  
Vol 134 ◽  
pp. 213-224
Author(s):  
Rosario del Carmen Flores-Vallejo ◽  
Jorge Luis Folch-Mallol ◽  
Ashutosh Sharma ◽  
Alexandre Cardoso-Taketa ◽  
Laura Alvarez-Berber ◽  
...  
Keyword(s):  
Metabolic Profiling ◽  
Fungal Endophytes ◽  
Anti Inflammatory ◽  
Mexican Species

In vitro selection of a fungal pathogen for use against Diaphorina citri

2015 ◽  
Vol 90 ◽  
pp. 6-15 ◽  
Author(s):  
N. Orduño-Cruz ◽  
A.W. Guzmán-Franco ◽  
E. Rodríguez-Leyva ◽  
R. Alatorre-Rosas ◽  
H. González-Hernández ◽  
...  
Keyword(s):  
Fungal Pathogen ◽  
In Vitro Selection ◽  
Diaphorina Citri ◽  
Selection Of

scholarly journals Two new species of Undifilum, fungal endophytes of Astragalus (locoweeds) in the United States

Botany ◽  
2012 ◽  
Vol 90 (9) ◽  
pp. 866-875 ◽  
Author(s):  
Deana L. Baucom ◽  
Marie Romero ◽  
Robert Belfon ◽  
Rebecca Creamer
Keyword(s):  
New Species ◽  
New Mexico ◽  
Random Amplified Polymorphic Dna ◽  
Phylogenetic Analyses ◽  
Fungal Endophytes ◽  
Morphological Characteristics ◽  
Its Region ◽  
The United States ◽  
Neighbor Joining

New species of Undifilum , from locoweeds Astragalus lentiginosus Vitman and Astragalus mollissimus Torr., are described using morphological characteristics and molecular phylogenetic analyses as Undifilum fulvum Baucom & Creamer sp. nov. and Undifilum cinereum Baucom & Creamer sp. nov. Fungi were isolated from dried plants of A. lentiginosus var. araneosus , diphysus , lentiginosus , and wahweapensis collected from Arizona, Oregon, and Utah, USA, and A. mollissimus var. biglovii , earleii , and mollissimus collected from New Mexico, Oklahoma, and Texas, USA. Endophytic fungi from Astragalus locoweeds were compared to Undifilum oxytropis isolates obtained from dried plant material of Oxytropis lamberteii from New Mexico and Oxytropis sericea from Arizona, Colorado, New Mexico, Utah, and Wyoming. Extremely slow growth in vitro was observed for all, and conidia, if present, were ellipsoid with transverse septa. However, in vitro color, growth on four different media, and conidium size differed between fungi from Astragalus spp. and U. oxytropis. Neighbor-joining analyses of internal transcribed spacer (ITS) region and glyceraldehyde-3-phosphate dehydrogenase (GPD) gene sequences revealed that U. fulvum and U. cinereum formed a clade distinct from U. oxytropis. This was supported by neighbor-joining analyses of results generated from random amplified polymorphic DNA (RAPD) fragments using two different primers.

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