The Effect of Colchicine Application Method on Reproductive Traits of Pot Marigold (Calendula officinalis L.)

Colchicine is a mutagenesis chemical compound that causes many changes in plants by mutation induction. This study was conducted to evaluate the effect of application method of colchicine on epigenetic traits and reproductive phase in two yellow and orange flower genotype of pot marigold (Calendula officinalis L.). The experiment was arranged in factorial based on randomized complete block design with three replications. The first factor was two methods of seed immersion for 48 hours and spray in two true leaves stage and the second factor was different colchicine concentrations (0, 0.02, 0.04, 0.06 percentage). Flow cytometric studies showed that the colchicine affected polyploidy induction in the foliar spray. In fact, polyploidy induction was increased with increase in concentration of colchicine. The results showed that in both genotypes, lengh and diameter of flower capitol bud, flower capitol diameter, ligulate floret number, ligulate floret length and diameter of inflorescence stem were increased but tubular floret number, plant height and length of inflorescence stem were decreased (P< 0.05) in plants obtained in treatment of immersing seeds in cilchicine compared with control, but the length and diameter of pollen grain and pollen- vigorous rate were not affected. Length and diameter of flower capital bud, flower capitol diameter, ligulate floret number, ligulate and pollen- vigorous rate were decreased in foliar spray treatment and tubular floret number, plant height and diameter of pollen grain were increased (P <0.05). Ligulate floret width was similar in both seed immersion and foliar spray treatments compared to the control.