ecological factors related to community composition and dynamics
Santos-González, Juan Carlos
(2007).
Diversity of arbuscular mycorrhizal fungi in grasslands and arable fields.
Diss. (sammanfattning/summary)
Uppsala :
Sveriges lantbruksuniv.,
Acta Universitatis Agriculturae Sueciae, 1652-6880
; 2007:105
ISBN 978-91-85913-04-6
[Doctoral thesis]
![]() |
PDF
2MB |
Abstract
This thesis comprises four studies on the identification and ecology of arbuscular mycorrhizal fungi (AMF) in grasslands and in arable soils. Fungi belonging to the phylum Glomeromycota are obligate symbionts in the roots of land plants where they form arbuscular mycorrhiza. The symbiotic association increases the ability of the host plant to take up nutrients from the soil via the extensive mycelia of the fungal symbionts, which have a larger and better distributed surface area for uptake than the roots alone. In turn, the fungi obtain carbohydrates that the plants produce. Arbuscular mycorrhiza are almost ubiquitous in grasslands, and therefore assumed to play a key role in ecosystem functioning. AMF taxa in the plant roots were identified with the use of different molecular techniques. Their phylogenetic affiliations were investigated and the significance of some relevant ecological factors shaping the AMF community structure was evaluated. In a seminatural grassland, we observed that AMF richness decreased in relation to increasing levels of nitrogen in the soil. The temporal patterns and species composition of the fungal communities colonizing the roots of two co-existing plant species were also shown to be different. We also found that AMF communities colonizing a single plant species varied between different localities within the same region. We used a long-term field experiment to show how different management practices affected the microbial soil biota. We compared the application of different organic and inorganic fertilisers, and their effect upon the AM fungi colonizing maize roots and the bacteria in root-associated soil aggregates. Some amendments induced dramatic changes in the richness and composition of the bacterial and the fungal communities. In conclusion, our experiments revealed evidence of complex ecological patterns in this cryptic but important group of fungi. Human management practices in grasslands and arable fields can shape the communities of both AMF and bacteria in the soil. Improved knowledge of the spatial and temporal niches of different taxa is a prerequisite in order to design manipulative experiments that can establish the link between taxonomical and functional diversity.
Authors/Creators: | Santos-González, Juan Carlos | ||||
---|---|---|---|---|---|
Title: | Diversity of arbuscular mycorrhizal fungi in grasslands and arable fields | ||||
Subtitle: | ecological factors related to community composition and dynamics | ||||
Year of publishing : | 2007 | ||||
Number: | 2007:105 | ||||
Number of Pages: | 30 | ||||
Papers/manuscripts: |
| ||||
Place of Publication: | Uppsala | ||||
ISBN for printed version: | 978-91-85913-04-6 | ||||
ISSN: | 1652-6880 | ||||
Language: | English | ||||
Publication Type: | Doctoral thesis | ||||
Full Text Status: | Public | ||||
Agrovoc terms: | vesicular arbuscular mycorrhizae, fungi, rRNA, genes, grasslands, arable land, microbial ecology | ||||
Keywords: | arbuscular mycorrhiza, Glomeromycota, rRNA gene, microbial ecology, grasslands, arable fields | ||||
URN:NBN: | urn:nbn:se:slu:epsilon-1837 | ||||
Permanent URL: | http://urn.kb.se/resolve?urn=urn:nbn:se:slu:epsilon-1837 | ||||
ID Code: | 1545 | ||||
Department: | (NL, NJ) > Dept. of Forest Mycology and Plant Pathology (S) > Dept. of Forest Mycology and Plant Pathology | ||||
Deposited By: | Juan Carlos Santos-González | ||||
Deposited On: | 03 Oct 2007 00:00 | ||||
Metadata Last Modified: | 02 Dec 2014 10:12 |
Repository Staff Only: item control page