scholarly journals Towards Growth of Arbuscular Mycorrhizal Fungi Independent of a Plant Host

2002 ◽  
Vol 68 (4) ◽  
pp. 1919-1924 ◽  
Author(s):  
Ulrich Hildebrandt ◽  
Katharina Janetta ◽  
Hermann Bothe
Keyword(s):  
Mycorrhizal Fungi ◽  
Glomus Intraradices ◽  
Mycorrhizal Fungus ◽  
Fungal Growth ◽  
Arbuscular Mycorrhizal ◽  
Plant Host ◽  
Significant Step ◽  
Hyphal Coils ◽  
K 12 ◽  
Root Tissues

ABSTRACT When surface-sterilized spores of the arbuscular mycorrhizal fungus (AMF) Glomus intraradices Sy167 were germinated on agar plates in the slightly modified minimum mineral medium described by G. Bécard and J. A. Fortin (New Phytol. 108:211-218, 1988), slime-forming bacteria, identified as Paenibacillus validus, frequently grew up. These bacteria were able to support growth of the fungus on the agar plates. In the presence of P. validus, hyphae branched profusely and formed coiled structures. These were much more densely packed than the so-called arbuscule-like structures which are formed by AMF grown in coculture with carrot roots transformed with T-DNA from Agrobacterium rhizogenes. The presence of P. validus alone also enabled G. intraradices to form new spores, mainly at the densely packed hyphal coils. The new spores were not as abundant as and were smaller than those formed by AMF in the monoxenic culture with carrot root tissues, but they also contained lipid droplets and a large number of nuclei. In these experiments P. validus could not be replaced by bacteria such as Escherichia coli K-12 or Azospirillum brasilense Sp7. Although no conditions under which the daughter spores regerminate and colonize plants have been found yet, and no factor(s) from P. validus which stimulates fungal growth has been identified, the present findings might be a significant step forward toward growth of AMF independent of any plant host.

Quantifying the growth of arbuscular mycorrhizal fungi: usefulness of the fractal dimension

Botany ◽  
2009 ◽  
Vol 87 (4) ◽  
pp. 387-400 ◽  
Author(s):  
Christine Juge ◽  
Annie Champagne ◽  
Andrew P. Coughlan ◽  
Nicolas Juge ◽  
Lael Parrott ◽  
...  
Keyword(s):  
Fractal Dimension ◽  
Mycorrhizal Fungi ◽  
Growth And Development ◽  
Time Course ◽  
Glomus Intraradices ◽  
Fungal Growth ◽  
Arbuscular Mycorrhizal ◽  
Hyphal Growth ◽  
Growth Cycle

The present study is, to the best of our knowledge, the first to investigate the use of the fractal dimension (FD) to quantify the growth and development of undisturbed, fully functional arbuscular mycorrhizal (AM) hyphae developing in vitro. The majority of the work focused on the model AM fungus Glomus intraradices DAOM 181602. The time course study and final measurements of an intact mature extraradical mycelium allowed us to compare the development of the mycelium and the FD value. The final FD value of 1.62 for the mature mycelium is similar to that obtained for highly branched root systems and tree crowns. The FD method was used to characterize the morphology of germinative and presymbiotic hyphae in the presence of stimulatory (strigolactone GR-24, 0.1 µmol·L–1 and bisphenol A, 10 µmol·L–1) and inhibitory (NaCl, 80 mmol·L–1) molecules, and the extraradical phase in the presence of an inhibitory molecule (NaCl, 80 mmol·L–1). Where possible, results were compared with those obtained using the traditional grid-line (GL) technique. The FD approach allowed treatment effects to be accurately quantified, both in germinative and extraradical phases. In the second case, this technique provided a single quantitative value of extraradical hyphal growth that included runner hyphae (RH) networks, and fine-branching (FB) ramifications. This is in contrast to the GL technique, which provides a value for the estimation of RH, but which is not suitable for accurately measuring FB hyphae. Given the ease with which the FD values can be calculated, and the fact that this method can provide a single value for the quantification of extraradical hyphal growth and development, we suggest that this method is useful for in vitro studies. Furthermore under certain situations of germinative or presymbiotic growth, it may be used in concert with the GL method to provide a greater degree of information about hyphal morphology. The usefulness and limits of the FD method at different stages of the AM fungal growth cycle are discussed.

scholarly journals Colonization and Growth Effects of the Mycorrhizal Fungus Glomus intraradicies in a Commercial Nursery Container Production System

2000 ◽  
Vol 18 (4) ◽  
pp. 247-251
Author(s):  
F.T. Davies ◽  
J.A. Saraiva Grossi ◽  
L. Carpio ◽  
A.A. Estrada-Luna
Keyword(s):  
Production System ◽  
Mycorrhizal Fungi ◽  
Host Plants ◽  
Glomus Intraradices ◽  
Mycorrhizal Fungus ◽  
Arbuscular Mycorrhizal ◽  
Dry Mass ◽  
Fertility Level ◽  
Mycorrhizal Development ◽  
Container Production

Abstract The objectives of this research were to demonstrate that mycorrhiza can survive in a commercial nursery container production system, and enhance plant productivity. Four species were used as host plants [Nandina domestica ‘Moon Bay’, Loropetalum chinense variety Rubrum ‘Hinepurpleleaf’ Plumb delight®, Salvia gregii, and Photinia fraseri]. Plants were inoculated with arbuscular mycorrhizal fungi, Glomus intraradices, and grown in a commercial nursery in Texas. For the first 5.5 months, plants were grown in #1 cans containing either 3 kg cu m (5 lbs cu yd) or 4.2 kg cu m (7 lbs cu yd) 24N–4P205–8K20. For the final 6.5 months of the study, plants were in larger containers, all of which contained 4.2 kg cu m (7 lbs cu yd) 24N–4P2O5–8K2O. The commercial inoculum of Glomus intraradices only enhanced growth of N. domestica. The shoot dry mass of mycorrhizal N. domestica plants at 3 kg cu m was the same as non-colonized plants at the higher fertility level of 4.2 cu m. Intraradical hyphae development and colonization (total arbuscules, vesicles/endospores, hyphae) of L. chinense, N. domestica, and S. gregii increased at the higher fertility levels. S. gregii had the greatest mycorrhizal development and a 216% increase in hyphae development and colonization at the higher fertility level.

Symbiosis of Acacia auriculiformis and Acacia mangium with mycorrhizal fungi and Bradyrhizobium spp. improves salt tolerance in greenhouse conditions

2005 ◽  
Vol 32 (12) ◽  
pp. 1143 ◽  
Author(s):  
Diégane Diouf ◽  
Robin Duponnois ◽  
Amadou Tidiane Ba ◽  
Marc Neyra ◽  
Didier Lesueur
Keyword(s):  
Salt Tolerance ◽  
Mineral Nutrition ◽  
Mycorrhizal Fungi ◽  
Glomus Intraradices ◽  
Mycorrhizal Fungus ◽  
Acacia Mangium ◽  
Arbuscular Mycorrhizal ◽  
Ectomycorrhizal Fungus ◽  
Acacia Auriculiformis ◽  
Acacia Species

The aim of our work was to assess the growth and mineral nutrition of salt stressed Acacia auriculiformis A. Cunn. ex Benth. and Acacia mangium Willd. seedlings inoculated with a combination of selected microsymbionts (bradyrhizobia and mycorrhizal fungi). Plants were grown in greenhouse conditions in non-sterile soil, irrigated with a saline nutrient solution (0, 50 and 100 mm NaCl). The inoculation combinations consisted of the Bradyrhizobium strain Aust 13c for A. mangium and Aust 11c for A. auriculiformis, an arbuscular mycorrhizal fungus (Glomus intraradices, DAOM 181602) and an ectomycorrhizal fungus (Pisolithus albus, strain COI 007). The inoculation treatments were designed to identify the symbionts that might improve the salt tolerance of both Acacia species. The main effect of salinity was reduced tree growth in both acacias. However, it appeared that, compared with controls, both rhizobial and mycorrhizal inoculation improved the growth of the salt-stressed plants, while inoculation with the ectomycorrhizal fungus strain appeared to have a small effect on their growth and mineral nutrition levels. Endomycorrhizal inoculation combined with rhizobial inoculation usually gave good results. Analysis of foliar proline accumulation confirmed that dual inoculation gave the trees better tolerance to salt stress and suggested that the use of this dual inoculum might be beneficial for inoculation of both Acacia species in soils with moderate salt constraints.

scholarly journals Changes in essential oil and morpho-physiological traits of tarragon (Artemisia dracuncalus L.) in responses to arbuscular mycorrhizal fungus, AMF (Glomus intraradices N.C. Schenck & G.S. Sm.) inoculation under salinity

2017 ◽  
Vol 109 (2) ◽  
pp. 215
Author(s):  
Amin Lamian ◽  
Hassanali Naghdi Badi ◽  
Ali Mehrafarin ◽  
Mehdi Seif Sahandi
Keyword(s):  
Essential Oil ◽  
Mycorrhizal Fungi ◽  
Glomus Intraradices ◽  
Mycorrhizal Fungus ◽  
Arbuscular Mycorrhizal ◽  
Physiological Traits ◽  
Bornyl Acetate ◽  
Methyl Chavicol ◽  
Salinity Condition ◽  
Amf Inoculation

This study aimed to evaluate the arbuscular mycorrhizal fungi (AMF) (<em>Glomus intraradices </em>N.C. Schenck &amp; G.S. Sm.) inoculation and salinity effect on qualitative and quantitative changes in tarragon yield. Treatments included inoculation, and non-inoculation of AMF, and five salinity levels of irrigation water (with the electrical conductivity of 0, 2, 4, 6, and 8 dS m<sup>-1</sup>). The results showed the plant height, SPAD value, number of leaves, dry mass of leaves and shoot per plant were reduced under salinity condition. The various levels of salinity decreased the content of tarragon essential oil and some its components consist of <em>α</em>-pinene, limonene, <em>Z</em>-ocimene, <em>E</em>-ocimene, and methyl chavicol while, it increased the content of bornyl acetate, eugenol, methyl eugenol, caryophyllene, germacrene, and <em>α</em>-farnesene. AMF inoculation without salinity had the greatest positive effect on the evaluated traits of tarragon. Also, it improved the morpho-physiological traits under salinity due to alleviation of the harmful effects of salinity. Although the essential oil content was reduced with the AMF inoculation, the methyl chavicol amount was increased by the AMF inoculation under salinity condition.

scholarly journals Influence of Arbuscular Mycorrhizae on Callusing and root colonization of Tea (Camellia sinensis) Clones in Kenya

2021 ◽  
pp. 21-26
Author(s):  
Awa Chelangat ◽  
Joseph P. Gweyi-Onyango ◽  
Nicholas K. Korir ◽  
Maina Mwangi
Keyword(s):  
Chlorophyll Content ◽  
Mycorrhizal Fungi ◽  
Arbuscular Mycorrhizae ◽  
Glomus Intraradices ◽  
Soil Phosphorus ◽  
Block Design ◽  
Mycorrhizal Fungus ◽  
Arbuscular Mycorrhizal ◽  
Iron Aluminum ◽  
Standard Application

Mycorrhizal fungi are a major component of the soil micro flora in many ecosystems, but usually have limited saprophytic abilities. Arbuscular mycorrhizal fungi (AMF) are an important component of soil life and soil chemistry. In soil, phosphorus may be present in relatively large amounts, but much of it is poorly available because of the very low solubility of phosphates by formation of complexes with iron, aluminum, and calcium, leading to soil solution concentrations of 10μm or less and very low mobility. Tea is a major income earner in the country, but yields are declining since high yielding tea varieties have a major problem with rooting and take so long in the nursery. The current study was initiated to investigate the role between Mycorrhizae and plants to explain rooting and growth rates during early stages of tea establishment. It was conducted at James Finlay in Kericho County, Kenya. The experiment was laid out in a Randomized Complete Block Design (RCBD) with factorial arrangements. Phosphorus treatments consisted of a standard rate of 107.66kg ha -1, two clones of the tea (S15/10 and SC 12/28) and two mycorrhizal strains (Glomus mosseae and Glomus intraradices) plus one control without mycorrhizae. Data was collected on rate of callusing, chlorophyll content and rate of root infection by mycorrhizal fungus. Application of 50kg Mycorrhizae ha-1 exhibited the highest callusing rate on clone SC 15/10 with significant differences (P≤0.05) observed on the chlorophyll content from week 1 to week 30 where the standard application of phosphorus plus 50kg Mycorrhizae ha-1 on clone S 15/10 had the highest content consistently throughout the trial. The highest frequency of mycorrhizae colonization in the rhizosphere was observed when 70kg ha-1 was added under clone SC 12/28. AMF strains are recommended for use on tea propagation in improving callusing rate and the chlorophyll content at a rate of 50kg Mycorrhizae ha-1.

scholarly journals Inoculation with Vesicular-Arbuscular Mycorrhizal Fungi and Rhizobacteria Alters Nutrient Allocation and Flowering of Harlequin Flower

2004 ◽  
Vol 14 (1) ◽  
pp. 39-48 ◽  
Author(s):  
C.F. Scagel
Keyword(s):  
Mycorrhizal Fungi ◽  
Glomus Intraradices ◽  
Mycorrhizal Fungus ◽  
Arbuscular Mycorrhizal ◽  
Leaf Production ◽  
Flower Production ◽  
Beneficial Effects ◽  
Vesicular Arbuscular ◽  
Shoot Emergence

We assessed whether addition of arbuscular mycorrhizal fungus (AMF) inoculum or rhizosphere organisms from AMF inoculum alters aspects of flowering, corm production, or corm quality of harlequin flower (Sparaxis tricolor) for two growth cycles after inoculation. Using pasteurized and nonpasteurized growth medium, plants were inoculated with either inoculum of the AMF, Glomus intraradices, or washings of the inoculum containing rhizobacteria. Shoots of plants inoculated with AMF emerged 2 days earlier than shoots on noninoculated plants or plants inoculated with inoculum washings. Flowers on AMF-inoculated plants opened 7-8 days earlier and plants produced more flowers per plant and per inflorescence than noninoculated plants. AMF-inoculated plants partitioned a higher proportion of biomass to cormel production than to daughter corms and had higher concentration and contents of zinc, sulfur, nitrogen, amino acids, and carbohydrates than corms from noninoculated plants. The rhizosphere organisms associated with the AMF inoculum influenced several measures of plant development, growth, and corm production suggesting that there are organisms associated with our AMF inoculum that have beneficial effects on the growth and productivity of harlequin flower. While inoculation with AMF can promote shoot emergence, leaf production, and flower production of harlequin flower, inoculation also alters aspects of biomass partitioning and corm composition that play an important role in the production of this crop for corms and cormels.

scholarly journals A Phosphate Transporter Gene from the Extra-Radical Mycelium of an Arbuscular Mycorrhizal Fungus Glomus intraradices Is Regulated in Response to Phosphate in the Environment

2001 ◽  
Vol 14 (10) ◽  
pp. 1140-1148 ◽  
Author(s):  
Ignacio E. Maldonado-Mendoza ◽  
Gary R. Dewbre ◽  
Maria J. Harrison
Keyword(s):  
Mycorrhizal Fungi ◽  
Glomus Intraradices ◽  
Arbuscular Mycorrhizal Fungus ◽  
Mycorrhizal Fungus ◽  
Arbuscular Mycorrhizal ◽  
Arbuscular Mycorrhizas ◽  
Phosphate Transporter ◽  
Transporter Gene ◽  
Symbiotic Associations ◽  
Mycorrhizal Association

The majority of vascular flowering plants are able to form symbiotic associations with arbuscular mycorrhizal fungi. These symbioses, termed arbuscular mycorrhizas, are mutually beneficial, and the fungus delivers phosphate to the plant while receiving carbon. In these symbioses, phosphate uptake by the arbuscular mycorrhizal fungus is the first step in the process of phosphate transport to the plant. Previously, we cloned a phosphate transporter gene involved in this process. Here, we analyze the expression and regulation of a phosphate transporter gene (GiPT) in the extra-radical mycelium of the arbuscular mycorrhizal fungus Glomus intraradices during mycorrhizal association with carrot or Medicago truncatula roots. These analyses reveal that GiPT expression is regulated in response to phosphate concentrations in the environment surrounding the extra-radical hyphae and modulated by the overall phosphate status of the mycorrhiza. Phosphate concentrations, typical of those found in the soil solution, result in expression of GiPT. These data imply that G. intraradices can perceive phosphate levels in the external environment but also suggest the presence of an internal phosphate sensing mechanism.

Effects of external phosphate concentration on glucose-6-phosphate dehydrogenase gene expression in the arbuscular mycorrhizal fungus Glomus intraradices

2006 ◽  
Vol 52 (9) ◽  
pp. 823-830 ◽  
Author(s):  
L I Stewart ◽  
S Jabaji-Hare ◽  
B T Driscoll
Keyword(s):  
Gene Expression ◽  
Mycorrhizal Fungi ◽  
Glomus Intraradices ◽  
Arbuscular Mycorrhizal Fungus ◽  
Mycorrhizal Fungus ◽  
Arbuscular Mycorrhizal ◽  
Pentose Phosphate ◽  
Dehydrogenase Gene ◽  
Significant Difference ◽  
Glucose 6 Phosphate Dehydrogenase

Specific primers were developed to amplify a 227 bp segment of the arbuscular mycorrhizal fungus Glomus intraradices gene encoding glucose-6-phosphate dehydrogenase (G6PDH), an enzyme involved in the pentose phosphate pathway. G6PDH gene expression was measured by real-time quantitative reverse transcriptase – polymerase chain reaction in response to phosphorus (P) concentrations in the growth medium of colonized transformed carrot roots. We investigated the effects of different P concentration treatments on carbon (C) metabolism within the intraradical mycelia of G. intraradices. The results showed a significant (P = 0.017) down-regulation of G6PDH expression in the intraradical mycelia of G. intraradices cultures grown in high P than low P conditions but no significant difference in regulation in excessive P concentrations when compared with the low P or high P concentrations. These results indicate that a reduction in the C flow from the host could be occurring as a result of elevated P and that a decrease in fungal G6PDH gene expression occurs, but not in the short term (less than 2 h). Reduced C flow from the host could lead to reduced fungal growth and root colonization, as was observed under high soil P conditions.Key words: arbuscular mycorrhizal fungi, phosphorus, nutrient uptake, glucose-6-phosphate dehydrogenase, gene expression.

scholarly journals Mycorrhizal Fungi in Rooting Substrate Influences the Quantity and Quality of Roots on Stem Cuttings of Hick's Yew

2003 ◽  
Vol 13 (1) ◽  
pp. 62-66 ◽  
Author(s):  
C.F. Scagel ◽  
K. Reddy ◽  
J.M. Armstrong
Keyword(s):  
Root Growth ◽  
Mycorrhizal Fungi ◽  
Glomus Intraradices ◽  
Mycorrhizal Fungus ◽  
Arbuscular Mycorrhizal ◽  
Root Initiation ◽  
Stem Cuttings ◽  
Primary Roots ◽  
Vesicular Arbuscular

In a commercial nursery propagation system for hick's yew (Taxu×media `Hicksii'), we assessed whether or not the addition of inoculum of the vesicular-arbuscular mycorrhizal fungus (VAMF) Glomus intraradices into the rooting substrate during cutting propagation increased rooting, and how the quantity of inoculum influenced rooting. At 15 and 22 weeks (108 and 156 d) after cuttings were treated with root hormones and stuck, root initiation was higher on cuttings stuck in the rooting substrate containing VAMF inoculum. Increasing the quantity of inoculum in the rooting substrate increased root growth during the early stages of rooting. However the highest level of inoculum tested increased adventitious root initiation without increased root growth. Our results indicate that if VAMF inoculum is used during propagation from cuttings, there are optimal levels required to alter the initiation and growth of roots. For hick's yew, 1:100 or 2:100 (by volume) rates of G. intraradices in the rooting substrate increased the number of primary roots and growth of adventitious roots on cuttings above that achieved by using rooting hormone alone.

scholarly journals Effects of Vesicular–Arbuscular Mycorrhizal Fungi on Rooting and Growth of Two Woody Ornamentals

HortScience ◽  
1997 ◽  
Vol 32 (3) ◽  
pp. 447C-447
Author(s):  
Martin Trépanier ◽  
Jacques-André Rioux
Keyword(s):  
Mycorrhizal Fungi ◽  
Glomus Intraradices ◽  
Ornamental Plants ◽  
Mycorrhizal Fungus ◽  
Arbuscular Mycorrhizal ◽  
Mineral Elements ◽  
Cornus Sericea ◽  
Vesicular Arbuscular ◽  
Rooting Media ◽  
Juniperus Sabina

A commercial inoculum of Glomus intraradices Schenk and Smith, a vesicular–arbuscular mycorrhizal fungus, has been used with the objective of studying its effects on rooting and on subsequent growth of two woody ornamental plants (Juniperus Sabina `Blue Danube' and Cornus sericea `Coloradensis'). This inoculum, called Mycorise™, is produced by Premier Peat Co. (Rivière-du-Loup, Québec, Canada) and it contains one propagule/g of Glomus intraradices. The cuttings's rooting media was mixed in order to contain 0%, 10%, 20%, 40%, or 80% of inoculum. Hardwood cuttings have been inserted in 65-ml cells and put under a mist until good rooting. For both species used, presence of inoculum in rooting media has not given significant effects during the rooting stage of cuttings, but has given some during the following stage of growth in 6-L containers. The growth of young mycorrhized plants of Juniperus was up to 50% greater than the control after the first season of growth. The young plants of Cornus have only showed a tendency to have a higher growth. Moreover, several mineral elements (N, P, Ca, Mn, Zn) were present at higher concentrations on mycorrhized plants. For roots colonization by the fungus and growth results, the inoculum proportion of the rooting media the most appropriate for Juniperus Sabina `Blue Danube', a slow-rooting species, was 40%, and the most appropriate for Cornus sericea `Coloradensis', a quick-rooting species, was 20%.

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