Establishment of micropropagation protocol for Chrysanthemum (Chrysanthemum morifolium Ramat) mutants following their physiological study

Abstract

Micropropagation is an important technique for in vitro preservation of Chrysanthemum morifolium Ramat mutant types. This work developed a micropropagation methodology for chrysanthemum mutant types following analysis of chlorophyll content and few molecular investigations. In this experiment mainly hormone free MS medium was used for regeneration response study and the results of different mutants were evaluated. Shoot tips were collected from the ex-vivo grown plants and were subjected to sterilization. Among the used sterilization treatments B and G showed the best result for regeneration response (100%) through controlling the contamination rate. Treatment B was running tap water for 25 mins, detergent wash 10 mins and 0.8% NaClO for 10 mins and treatment G was running tap water for 25 mins, detergent wash 15 mins and 0.1% HgClO for 2 mins and 70% ethanol for 20 sec. The establishment of branching on the sterilized shoots on hormone free MS medium took 7 to 8 days after inoculation and roots were visible after 7 weeks. The fully rooted plantlets could stay healthy inside the flasks for 8 weeks. Once needed rooted plantlets were transferred to soil and acclimatized properly. Plantlets derived from this study showed 100% survival during acclimatization. For chlorophyll study, mutant 6 (M6) showed the best result (chlorophyll content was 0.0028685185) among all the mutants tested. Thus, this work increases knowledge for preservation of chrysanthemum mutant types by developing a micropropagation methodology. The evaluation of chlorophyll content will help to present deeper insights into their genetic and physiological properties.