Mohammad Abdoli - Department of Plant Production and Genetics, Faculty of Agriculture, Malayer University, Malayer, Iran
Nooshin Koolivand - Department of Plant Production and Genetics, Faculty of Agriculture, Malayer University, Malayer, Iran
Arash Babaei - Department of Biology, Faculty of Sciences, Malayer University, Malayer, Iran

The present study aimed to develop a protocol for root induction and evaluate the effects of salicylic acid (SA) (۰, ۸۰ and ۱۶۰ mg/l) and yeast extract (YE) (۰, ۰.۷۵ and ۱.۵ g/l) on chlorogenic acid, caftaric acid, cichoric acid, cynarin and echinacoside production in Echinacea purpurea adventitious roots. Also, the effect of NH۴NO۳ (۰, ۰.۲۵, ۰.۷۵, ۱.۰ X) concentration in MS medium supplemented with indole-۳-acetic acid (IAA) (۱ and ۳ mg/l) on root induction was investigated. The results showed that adventitious root induction in coneflower was significantly influenced by NH۴NO۳ and IAA concentrations (p≤۰.۰۱). The highest percentage of root induction (۱۰۰%) and average number of roots formed on each explant (۱۴.۳ roots) was observed in ۱ mg/l IAA×۱/۴NH۴NO۳ MS culture medium treatment. The main effect of SA and YE and their interaction effects with exposure time on the measured traits (except for echinacoside) was significant (p≤۰.۰۱). The result showed that application of ۱.۵ g/l YE and ۱۶۰ mg/l SA when harvested ۹۶ hour post-elicitation are the most effective treatments to elicit caffeic acid derivatives (CADs) content. The highest chlorogenic acid, cichoric acid, caftaric acid, and cynarin production was obtained in ۱۶۰ mg/l SA at ۹۶ hours post-elicitation that was ۲.۱۳, ۱.۸۳, ۲.۳۹ and ۲.۹۷-fold higher compared to control respectively. The heatmap diagram showed that the CADs content in SA and YE treatments was clearly separated from each other and control treatment.

Cichoric acid, Coneflower, Elicitor, In vitro, Medicinal plant, yeast extract