Chromosome variation and karyomorphology of Artemisia cina O.Berg: Comparison on Colchicine and 2,4-D + BA Treatment

Abstract In order to produce chromosome doubling in Artemisia cina, we undertook polyploidization. To generate polyploid plants, growth regulators and colchicines were employed. Colchicine treatment (0, 100, 150, 200 ppm) at immersion time of 24 hours, 48 hours, 72 hours, and 96 hours, and treatment 2,4-D and BA (combination of 2,4-D and BA at a concentration of 1–3 ppm) at 21 and 28 days of immersion are used as treatment. Ploidy number, chromosome size, and chromosome karyotype layout were all evaluated.The result of this study shows that a. cina treated with colchicine produced 37 polyploid plants with a distribution of 10.2% triploid, 15.2% tetraploid, 1.7% pentaploid, 1.7% hexaploid, and 0.8% tridecaploid plants. While the plants treated with growth regulators 2,4-D and BA produced 47 polyploid plants with a distribution of 2.5% triploid, 2.3% tetraploid, 1.5% pentaploid, 1.9% hexaploid, 0.4% septaploid, 0.4% octaploid. Plants treated using colchicine produced the most diversity in its ploidy while 2,4-D and BA produced more polyploidy plants and produced mixoploid plants with euploid or aneuploid chromosomes. Karyotype variance are more abundant in tetraploid, and the most uniform karyotype found in pentaploid plants. Colchicine is recommended to produce chromosome doubling rather than growth regulators.