Cytogenetic variation among populations of Aster thomsonii C. B. Clarke from district Sirmaur, Himachal Pradesh (India)

Abstract

Presently, cytomorphological investigations have been carried out in five populations of Aster thomsonii from different altitudinal areas of district Sirmaur (H.P.). The investigations revealed three cytomorphotypes: diploid (2n=18), tetraploid (2n=36) and hexaploid (2n=54). The chromosome count of 2n=54 (hexaploid cytotype) has been reported for the first time at world level. All the populations have anomalous meiotic course and reduced reproductive potential of 72, 81 and 59% for diploid, tetraploid and hexaploid, respectively.