Impact of Reciprocal Translocations and Non-Synchronous Disjunction of Chromosomes on Pollen Fertility in <i>Astragalus chlorostachys</i> from the Northwest Himalayas (India)

Abstract

Cytological investigations carried out on a population basis in Astragalus chlorostachys Lindl. which exists at diploid level (n=8) revealed the presence of quadrivalents, the late disjunction of 1–4 bivalents and some pollen sterility (34%) in 1 accession collected from Koksar, at 3140 m in the Lahaul Valley (Lahaul-Spiti, Himachal Pradesh). The presence of quadrivalents in this diploid species seems to be a consequence of reciprocal translocations. The occurrence of structural heterozygosity in the species has been reported here for the first time. All of the other populations showed normal bivalent formation and regular sporad generation and 100% pollen fertility. The paper here discusses in detail the course of meiosis and the effect of multivalent formation and non-synchronous disjunction of bivalents on meiotic course and pollen fertility.