Mutagenic Effects of EMS on Pollen Mother Cells of Catharanthus roseus (L.) G. Don

Abstract

Mutation can be beneficially utilized for tailoring crop plants. Chemical mutagen become one of important tools in crop improvement. Each mutagen has its important role as positive or negative effects on crops. Cytological abnormalities during meiosis has also been regarded one of the dependable parameters for estimating mutagenic sensitivity of a species. Studies undertaken in M₁ and M₂ generations on pink flower and white flower strains of Catharanthus roseus showed EMS elicit various chromosomal aberration in meiosis. Different types of meiotic abnormalities such as fragments, univalents, stickiness and unorientation of bivalents could be observed at metaphase I and bridges, laggards, unequal separation, unorientation of bivalents and stickiness could be seen at anaphase I. Meiotic abnormalities increased along with the increase in concentration in mutagens. The percentage of meiotic abnormalities was recorded maximum in M₁ generation as compared to M₂ generation. Contrary to pink, white flower strain exhibited maximum meiotic abnormalities and pollen sterility and hence, more sensitive to EMS. The highest pollen fertility was recorded in 0.2% concentration of EMS in pink flower strain of C. roseus.