Abstract
The combined effect of the arbuscular mycorrhizal (AM) fungusGlomus intraradices and the bacteriumBurkholderia cepacia onPythium ultimum was studied in a growth system with root-free soil compartments allowing examination of microbial interactions without direct interference from roots. Signature fatty acids were used to quantify individual microbial populations. Biomass and amount of energy reserves were estimated using specific phospholipid fatty acids (PLFA) and neutral lipid fatty acids (NLFA), respectively. Population density ofP. ultimum was estimated by colony forming units on selective media. Both biocontrol agents (BCAs) reduced population density ofP. ultimum. Biomass ofB. cepacia measured using signature fatty acids was inhibited by the presence of mycelium ofG. intraradices, which might explain why no additive effect onP. ultimum was found when combining the two BCAs. In conclusion, combiningG. intraradices andB. cepacia did not enhance the biocontrol efficacy againstP. ultimum.
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Larsen, J., Ravnskov, S. & Jakobsen, I. Combined effect of an arbuscular mycorrhizal fungus and a biocontrol bacterium againstPythium ultimum in soil. Folia Geobot 38, 145–154 (2003). https://doi.org/10.1007/BF02803147
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DOI: https://doi.org/10.1007/BF02803147