Nucleolar behavior in pollen mother cells in the pigeonpea

Abstract

Reports on the number of satellite chromosomes in the karyotype of Cajanus cajan are controversial, with the number varying from zero to two. Expression of nucleolar organizer chromosomes during melosis (prophase-I, telophase-I and telophase-II) is used as an index for the number of nucleolar organizers and conclusive evidence is provided for the presence of two nucleolar organizer chromosomes in Cajanus and also its related species in the genus Atylosia. Nucleolar number in an autotetraplold of Caianus confirmed the evidence from the diploid Cajanus for two nucleolar organizer chromosomes. Variation In the nucleolar size suggests that the two nucleolar organizer chromosomes differ in their activity.