Heteroplasmy is the state characterised by the presence of more than one type of mitochondrial or chloroplast genome in one organism. Infrequent recombinations across short repeated sequences often lead to heteroplasmy in higher plant mitochondria. Different Phaseolus species have been examined in order to understand the dynamics of heteroplasmy originating through recombination mediated by the 315 bp repeated sequence. Two techniques were applied to detect heteroplasmy: Souhern hybridization with prolonged autoradiography and PCR amplification followed by hybridization or reamplification. In all examined genomes the four recombination forms were detected. However, these forms do not occur in the same relative amounts. Moreover, in the examined genomes different recombination forms exist at the predominant/substoichiomeric level, but always only two of them are predominant. Based on these results and the previous data, we suggest that the changes in the heteroplasmic population of mitochondrial molecules in plants may offer the source of genetic variation in the course of evolution.