Meiotic behavior of Robertsonian heterozygotes in populations of Dichroplus pratensis with different fusion frequencies.

P. MIROL; C. BIDAU

GENETICA

Año: 1991 p. 171 - 178

0016-6707

The meiotic behavior of Robertsonian heterozygotes of Dichropluspratensis was analyzed in order to establish the nature of the fusion polymorphisms (stable or transient) that occur in the species. The range of fusion frequencies varies widely for each fusion studied and populations with extreme frequencies exist, which could indicate a tendency for the loss or fixation of a given rearrangement. Our results revealed that no significant correlation exists between orientation (convergent and non-convergent) in PM1 and MI and fusion frequency, nor between aneuploidy and fusion frequency. Thus, orientation and segregation seem to be independent of the frequencies of the fusions, which also do not appear to affect severely the fertility of heterozygotes. Our data suggest that the polymorphisms are, at least, cytogenetically stable.