Abstract
In order to analyse the action of 3B chromosome on homologous pairing in common wheat, effect of 3B deficiency on the pairing between the arms of an isochromosome (1A-long-arm) was investigated. Unlike the cases of colchicines and high temperature treatment, 3B deficiency proved to cause the failure of homologous pairing not only in arms of ordinary chromosomes but also in those of the isochromosome. From this result, the genetic factor on 3B seemed to affect synapsis, crossing over, and other chromosome behaviours in post-zygotene stages.
