Chromosomal diversity in three species of genus Rosa L. (Rosaceae) from district Kangra of Himachal Pradesh

Abstract

The chromosome number, detailed male meiosis, microsporogenesis and pollen fertility were examined in three species of the genus Rosa namely, Rosa brunonii (2n=14), R. indica (2n=14) and R. macrophylla (2n=14, 28). Of these, 2n=14 for R. brunonii and R. indica and 2n=28 for R. macrophylla makes a new records at India level. The course of meiosis varies from normal to abnormal in different populations of the species. The anomalous taxa are marked with meiotic abnormalities in the form of cytomixis, chromosomal stickiness, unoriented bivalents, formation of laggards and bridges resulting in abnormal microsporogenesis and production of heterogenous sized fertile pollen grains. All the taxa with normal meiotic course show high pollen fertility.