Biochemical systematics of some species in the genus Tuber

We report results on a systematic study of the genus Tuber using isozyme analysis. Eighteen enzyme loci were analyzed on numerous fruitbodies of various morphotaxa collected from different Spanish, French, Italian and Austrian locations. Fruitbodies were classified into 20 electrophoretic types based on isozyme polymorphisms. Genetic distances were analyzed by phenetic analysis. Based on the genetic and morphological differences, it was possible to confirm the specific status for T. magnatum, T. borchii, T. maculatum, T. puberulum, T. melanosporum, T. brumale and T. aestivum; whereas T. b. moschatum and T. uncinatum appeared to be morphological "varieties" of T. brumale and T. aestivum, respectively. High genetic distance values, ranging from D = 0.693 and D = 2.079, were observed among the taxa. Genetic heterogeneity was observed in T. borchii, T. maculatum and, particularly, T. aestivum, based on the presence of different electrophoretic types within these taxa. The source of genetic variation was discussed within an ecological context