Relationship between pairing frequencies and genome affinity estimations in aegilops ova ta X triticum aestivum hybrid plants

Abstract

Meiotic associations at metaphase I have been analysed in Aegilops ova ta x Triticum aestivum hybrid plants (genome constitution ABDUM) with low and high homoeologous pairing by using C-banding. Five different types of meiotic associations involving Aegilops and wheat genomes were identified. Pairing affinities between Aegilops and wheat genomes have been analysed from meiotic associations at metaphase I in low and high homoeologous pairing hybrid plants as well as from different meiotic configurations (bivalents and multivalents) in those hybrids with a high pairing mutant (phlb). Those kinds of distinguishable associations revealed the same relative order: AD-UM>A-D>U-M>AD-B>UM-B in both low and high homoeologous pairing hybrids. The mean number of associations per total associations (relative contribution) for the different distinguishable types of pairing was well maintained among hybrids with different levels of pairing (low and high) as well as in different meiotic configurations (bivalents and multivalents) in the high pairing plants. These results seem to indicate that the affinities expressed between the genomes that are in competition for pairing are independent of the meiotic configurations considered and on the level of pairing analysed. © 1992 The Genetical Society of Great Britain.