DE ARAUJO, ALVARO A.1, LAURE HANNIBAL1, CLAUDE PLASSARD2, DANIEL MOUSAIN2 & SEVASTIANOS ROUSSOS1.
1ORSTOM, Laboratoire de Biotechnologie, B.P. 5045, 34032 Montpellier cedex 1, France. * Scholarship CNPq/SFERE - Brazil 2 INRA, Laboratoire des Symbiotes des Racines, 2, Place Viala, 34060 Montpellier cedex 1. FRANCE.
Ectomycorrhizal fungi as Lactarius, Pisolithus, & Suilllus strains are considered as key microorganisms for qualitative improvement of trees and reforestation programmes. The objective of this study is to show how the ectomycorrhizal fungi inoculum production is influenced by nutritional parameters (culture media composition, carbon and nitrogen sources) during their growth on solid surface. These studies have been carried out both on agar media containing a Cellophane sheet on it and on solid substrate (sugarcane bagasse, peat/vermiculite) impregnated with a nutritive solution. Culture conditions as well as analysis such as apical growth, sugar consumption and biomass production are presented at this poster. Results show that Potato Dextrose Agar medium (PDA) is favorable for the mycelium growth of Pisolithus tinctorius, Lactarius deliciosus, Suilllus collinitus and Lactarius sanguiflius strains. A good mycelium development was observed for cultures on SSF (solid state fermentation) in which respirometric data reveled the influence of the age, the size of the inoculum as well as the influence of the light on the metabolism of these strains. State solid fermentation is a well adapted technique for mycelium development and the respirometry is a non destructive analytical method which permits to follow on line the ectomycorrhizal mycelium growth.
Key words: Physiology, Pisolithus, Lactarius, Suilllus, Solid State, Respirometry