The Presence and Behavior of B-Chromosomes in Meiocytes in Apluda mutica L.

Abstract

Accession based analysis in Apluda mutica studied from cytologically unexplored and phytogeographically isolated region of Uttarakhand, India revealed the existence of diploid chromosome count of 2n=20, normal meiosis and high pollen fertility. Individuals of three wild accessions however showed the presence of one to two B-chromosomes in 25.64 to 88.06% meiocytes. We here re-record the existence of B-chromosome in species from India. The Bs were noticed to behave differently, either as unpaired or showed regular pairing constituting B-bivalent when paired. B-Bivalent chromosomes also showed different behavior in the meiocytes. In, some cases, Bs disjunct regularly like A-chromosomes. But in some meiocytes they left failed to disjunct and both Bs get included at one pole. It has been inferred that Bs in the presently analysed accessions invariably affect the pollen grain formation and seem to be responsible for reducing pollen fertility.