MEIOTIC PAIRING BETWEEN SINGLE CHROMOSOMES OF DIPLOID AGROPYRON ELONGATUM AND DECAPLOID A. ELONGATUM IN TRITICUM AESTIVUM

Abstract

It is shown that meiotic pairing between single chromosomes of closely related taxa can be studied in hybrids between alien addition and substitution lines. Using this technique, two chromosomes of diploid A. elongatum which appear to be homoeologous with wheat chromosomes of groups 6 and 7 were shown to pair with chromosomes of decaploid A. elongatum which are also homoeologous with wheat chromosomes of groups 6 and 7. Hence, pairing of these chromosomes verified the suggested homoeology among these chromosomes.Meiotic pairing was also studied in 2 hybrid progenies which carried specific telosomes of diploid A. elongatum in addition to a set of 7 Agropyron chromosomes which came from decaploid A. elongatum. The telosomes paired with the decaploid A. elongatum chromosomes in these hybrids. Hence, four chromosomes of diploid A. elongatum were shown to pair in common wheat with chromosomes of decaploid A. elongatum. Since pairing between diploid A. elongatum and decaploid A. elongatum chromosomes was generally low, it is suggested that the chromosomes assigned to the same group are not homologous but rather closely homoeologous.