DIÉDHIOU, PAPA M. & HEINZ-W. DEHNE.
University of Bonn, Institute for Plant Diseases, Nussallee 9, D-53115 Bonn, GERMANY.
The use of arbuscular mycorrhizae (AM) to influence soilborne plant diseases is
based on their ability to promote plant health and reduce the damage caused by
the pathogens. AM have proved to control different pathogens - nematodes as
well as parasitic fungi. Similarly non-pathogenic strains of soilborne
pathogens can reduce the incidence of fungal disease and nematode infections.
These endophytes as well as AM are improving plant health with different
mechanisms like competition for infection sites and for host assimilates.
Biocontrol of nematodes using arbuscular mycorrhizal (AM) fungi and/or other
endophytes provides an alternative to replace the use of synthetic nematicides,
which have already been reduced due to environmental problems.
Tomato plants were preinoculated with Glomus spp. and a non-pathogenic
Fusarium oxysporum, individually or combined to identify the kind of
interaction between these biocontrol agents and their influence on the
sedentary nematodes. After establishment of the beneficial organisms the
nematodes were inoculated as juveniles of Meloidogyne incognita
Kofoid & White. Later the influence on plant growth, degree of colonisation
and gall formation by M. incognita were evaluated. The beneficial effect
of AM and the non-pathogenic F. oxysporum, their mutual interaction and
their influence on nematode infection will be discussed.
Key words: arbuscular mycorrhizae, biocontrol, non-pathogenic Fusarium oxysporum, Meloidogne incognita, Tomato