Different Phenotypes of Arbuscular Mycorrhizal Fungi from Field Roots of Argentina

SILVANI V.; PÉRGOLA M.; FERNÁNDEZ L.; FRACCHIA S.; GODEAS A.

Granada, España

Conferencia; V Conferencia Internacional en Micorrizas; 2006

We obtained arbuscular mycorrhizal fungi in trasformed roots from field colonizad roots, sampled from the providences of Buenos Aires, Salta and Córdoba (Argentina). Different continuous pure cultures of Glomus intraradices were obtained and hyphal growth rate and spore production was measured in each isolate. Hyphal lenght was measured by counting the number of hyphal intersects on an L-shaped line at tour randomly cosen positions on the plate. Spore density was measured by counting the number of spores in tour randomly cosen squares. Isolates differed significantly in their final hyphal length and spore number. The hyphal lenght ranged from 50 to 650m/plate and spore number ranged from 76 to 246 spores/cm-2. Also, differences in number of spores per cluste (1 to 25), spore diameter (31 to 85um) and morphology of branched absorbing structures (BAS) and mycelium were observed. Because the isolates were in a constant environment, phenotipic variation depended on genotypic variation. This varaition could be created by selection of diferente environments in the field and could explain differences in the plant ecological behaviour. Cultures were deposited in the bank of glomeromycota in Vitro (http:www.si.fcen.uba.ar).