Steep variation in mitochrondrial DNA and B chromosomes among natural populations of Eyprepocnemis plorans (Acrididae)

Abstract

Restriction enzyme analysis of the mitochondrial DNA of Eyprepocnemis plorans with 9 restriction enzymes revealed low variability - only Eco RI revealed any variability with 3 distinguishable digestion patterns, here named types I, II and III. The samples studied were collected from regions where different types of B chromosome exist. The demes from the central area show the B1 type (as a relict of a probably once continuous distribution) and also mtDNA type II. These show a parallel substitution towards the SW neighbouring demes by other Bs and mtDNA type I. However, the latter mtDNA type had a wider distribution and is predominant, or even the only one found in most other samples where other Bs exist. Considering the mtDNA as a marker unlinked with the Bs, some genetic differences should exist among areas defined by the B chromosomes. Our results support the hypothesis that in the central region the B chromosomes and the mtDNA are involved in two different events of substitution, but these do not necessarily occur in the same way.