An Infertile Triploid Population of Polystichum squarrosum from Himachal Pradesh

Abstract

Triploid cytotypes of Polystichum squarrosum have been found from India. All accessions shared the same cytological status of 2n=123, the first ever record against the earlier reported diploid (2n=82) and tetraploid (2n=164) cytotypes from India. Individuals depicted highly abnormal meiotic behavior characterized by presence of univalents beside bivalents, unoriented chromosomes at metaphase I (MI), laggards, chromatin bridges at anaphase and telophase. Cytomixis at tetrad showing nuclear fusion between sporads is another noticeable phenomenon in this species. Triads, polyads and micronuclei at tetrad stage consequently lead to low spore fertility and formation of heterogenous spores. B-chromosomes were found in few cells in one of the accessions.