Effect of colchicine on meiosis of Chrysanthemum carinatum Schousb. (Asteraceae)

The effect of colchicine was studied from the cytological point of view to induce mutation and develop polyploidy. The present study was conducted to determine the effect of colchicine on cell division and some morphological traits. Young seedling of Chrysanthemum carinatum Schousb. (2n=18) was treated with 0.2% colchicine. During meiotic analysis, reciprocal translocation heterozygote has been isolated among population of the colchicine treated Chrysanthemum carinatum Schousb. The translocation heterozygotes showed characteristics feature such as multivalent formation (mainly quadrivalents and hexavalent), univalent formation, bivalent associations, chromatin stickiness, chromosomal laggards, fragments and multipolar PMCs. At anaphase I, some pollen mother cells (PMCs) showed abnormal 8:10 chromosomal separation in addition to normal 9:9 separation. The treated populations showed reduction in plant survivability, plant height and delayed flowering. Induction of permanent chromosomal structural changes may also sometime bring out favorable morphological variation. It is expected that the mutant, when established, could be used in further cytological and breeding programs.