Different phenotypes of arbuscular mycorrhizal fungi from field roots of Argentina

SILVANI A, PERGOLA M, FERNANDEZ L, FRACCHIA S, GODEAS A

España

Congreso; International Conference On Mycorrhiza ICOM; 2006

Consejo Superior Investigaciones Científicas CSIC

Different phenotypes of arbuscular mycorrhizal fungi from field roots of Argentina We obtained arbuscular mycorrhizal fungi in transformed roots from field colonized roots, sampled from the provinces of Buenos Aires, Salta and Cordoba (Argentina). Different continuous pure cultures of Glomus intraradices were obtained and hyphal growth rate and spore production was measured in each isolate. Hyphal length was measured by counting the number of hyphal intersect on an L-shaped line at four randomly chosen positions on the plate. Spore density was measured by counting the number of spores infour randomly chosen squares. Isolates deffered significantly in their final hyphal length and spore number. The hyphal length ranged from 50 to 650m/plate and spore number ranged from 76 to 246 spores/cm-2. Also, differences in number of spores per cluster (1 to 25) spotres diameter (31 to 85um) and morphology of branched absorbing structures (BAS) and mycelium were observed. Because the isolates were in a constant enviroment, phenotypic variation depended on genotypic variation. This variations could be created by selection of different enviroments in the field and could explain differences in the plant ecological behavior. Cultures were deposited in the bank of glomeromycota in vitro (www.si.fcen.uba.ar)