Mycorrhizal succession and inoculant efficiency of dual inoculation on Eucalyptus urophylla

A pot experiment with dual inoculation of ectomycorrhizal and vesicular arbuscular mycorrhizal fungi in sterilized mix soil was undertaken to determine root colonisation and inoculant effects on Eucalyptus urophylla saplings. Successful colonisation of the two inoculated fungi, Glomus and Pisolithus, was observed with high infection rates at 5 months after inoculation. However the colonisation of each fungus on the roots of dual inoculated saplings decreased when comparing to that of individually inoculated ones. This would indicate the competition between the two fungi in the same root system. Inoculation with the two fungi alone or in combination significantly enhanced the growth of saplings. A positive correlation between the total root length of mycorrhizas and the dry weight of seedlings (r 2=0 79,P=0 05)was identified. Results also showed that both fungi could influence nutrient acquisition of eucalypt saplings.