Fermentation of sugar beet waste by ¤Aspergillus niger¤ facilitates growth and P uptake of external mycelium of mixed populations of arbuscular mycorrhizal fungi

A. Medina, Iver Jakobsen, N. Vassilev, R. Azcon, J. Larsen

    Research output: Contribution to journalJournal articleResearchpeer-review

    Abstract

    Sugar beet waste has potential value as a soil amendment and this work studied whether fermentation of the waste by Aspergillus niger would influence the growth and P uptake of arbuscular mycorrhizal (AM) fungi. Plants were grown in compartmentalised growth units, each with a root compartment (RC) and two lateral root-free compartments (RFC). One RFC contained untreated soil while the other RFC contained soil, which was uniformly mixed with sugar beet waste, either untreated (SB) or degraded by A. niger (ASB) in a rock phosphate (RP)-supplied medium. The soil in each pair of RFC was labelled with P-33 and (32)p in order to measure P uptake by the AM fungal mycelium, of which length density was also measured. Whole cell fatty acid (WCFA) signatures were used as biomarkers of the AM fungal mycelium and other soil microorganisms. The amount of biomarkers of saprotrophic fungi and both Grain-positive and Gram-negative bacteria was higher in SB than in ASB treatments. Whilst ASB increased growth and activity of AM mycelium, SB had the opposite effect. Moreover, shoot P content was increased by the addition of ASB, and by inoculation with AM fungi. Modification of soil microbial structure and production of exudates by A. niger, as a consequence of fermentation process of sugar beet waste, could possibly explain the increase of AM growth in ASB treatments. On the other hand, the highest P uptake was a result of the solubilisation of rock phosphate by A. niger during the fermentation. (c) 2006 Elsevier Ltd. All rights reserved.
    Original languageEnglish
    JournalSoil Biology & Biochemistry
    Volume39
    Issue number2
    Pages (from-to)485-492
    ISSN0038-0717
    DOIs
    Publication statusPublished - 2007

    Fingerprint Dive into the research topics of 'Fermentation of sugar beet waste by ¤Aspergillus niger¤ facilitates growth and P uptake of external mycelium of mixed populations of arbuscular mycorrhizal fungi'. Together they form a unique fingerprint.

    Cite this