QUANTIFICATION OF THE NUCLEAR-DNA CONTENT OF 2 ARBUSCULAR MYCORRHIZAL FUNGI

The nuclei of two arbuscular mycorrhizal fungi, Gigaspora margarita and Glomus versiforme, were examined cytofluometrically to (i) determine their DNA amount and (ii) look for differences in their genome size during some steps of their life cycle. The fluorescence characteristics of DNA-DAPI complex revealed that DNA amount is significantly different. This value expressed as arbitrary units and then quantified by using a biological standard is of 0.25-0.27 pg per nucleus in G. versiforme and 0.74-0.77 pg per nucleus in G. margarita. There were no differences between their individual spore and hyphal phases.