Controlled mycorrhization applied to improving the productivity of eucalyptus

[biotec at goliat.ugr.es]

A project entitled “Controlled mycorrhization applied to improving 
the productivity of eucalyptus industrial plantations in the wet 
tropics” lead by Dr. J. Garbaye of INRA-France, in partnership with 
other scientific institutions in France, Portugal, Brazil and Congo 
was carried out under the European Union (D.G.XII) STD2 scientific 
programme.
In a way this project is a follow up to another one STD1 programme, 
focusing the application of controlled mycorrhization to pines in 
the Congo.
The objective of the present research was to get knowledge about 
symbiosis, specially concerned with types, distribution, 
specificity, inoculation methods and some environmental effects. On 
a more technical approach, to go further on the knowledge of 
inoculation procedures, selection of fungal strains and the setting 
up of experimental plantations.
The mycorrhizal status of eucalyptus was studied in plantation 
(Congo and Brazil) and native stand (Australia and Papua Guinea). 
The mechanisms of specificity plant-fungus were tested in 
laboratory an differences on behaviour among fungal strains and 
among eucalyptus species were also investigated, as well as the 
effect of drought stress on the symbiosis. Also was tested the 
ability of the fungal strains to solubilize the rock phosphate and 
transfer orthophosphate to the root.
Tests were undertaken, in pots, nursery and greenhouse to evaluate 
the environmental effects of ectomycorrhiza formation and for 
optimising inoculation techniques.
In Portugal and Brazil different strains of Cenococum Geophilum, 
Pisolithos tinctorius and mycorrhiza were compared with native 
fungi from Australia, on seven plantations, which plants have been 
inoculated in the nursery.
In several areas auspicious results were obtained, especially in 
what concerns the knowledge of fungal strains associated with 
tropical eucalyptus in its native area.
New knowledge was achieved in the field of mechanism of 
specificity, aggressiveness (rapidity of infection), interaction 
between ectomycorrhiza and endomycorrhiza from the answer of 
ectomycorrhiza symbiosis drought stress and the fungal ability to 
solubilize the rock phosphate.
Some results are very stimulating, the best of them, point out to a 
30% increase in total height at 2 years, induced by strains of 
Pisolithos tinctorius.
We would like to finish by quoting the final summary report: “This 
project yielded a wide variety of new basic knowledge on the 
mycorrhizal symbioses of eucalyptus, published in 43 articles, 
communications and reports.
It also provided practical tools (laboratory tests) for a rapid 
screen of fungal isolates for controlled mycorrhization, and lead 
to the creation of experimental plantations which will produce new 
information during the next years. All the conditions are now 
favourable to technical experimentation on a larger scale.”
For further information please contact:
Dr J. Garbaye
Institut Nationale de la Recherche Agronomique
INRA
145 rue de l’Université
75007 Paris (France)
Phone (1) 42 75 90 00
Fax     (1) 42 75 94 86


Contract number A-093