Optimization of Callus Induction and Effects of Biological and Non- biological Elicitors on Content of Phenol/ Flavonoid Compounds in Nigella sativa under In-Vitro Conditions

Aim: This study attempts to optimize callus induction and analyze of yeast extract and nano-silver elicitors on phenol/flavonoid content in black cumin under tissue culture conditions.
Material and The experiment was conducted a factorial design based on CRD with three replications. Factors included: explants (root, hypocotyledon, leaf and Cotyledon), 2, 4-D (1, 2, 4 and 8 Mg/L) and BAP (0.25, 0.5, and 1 Mg/L) in MS base medium. Elictor's including yeast extract (100, 250 and 500 Mg/L) and nano-silver (30, 60 and 90 Mg/L) in two time (3 and 7 days) periods.
The results showed that hypocotyledon explant and interaction effect of BAP (0.25 Mg/L) and 2, 4-D (4 Mg/L) were the most effective on the callus induction percent. Direct regeneration was caused by the root explant and the interaction effect of BAP (0.5 Mg/L) and 2, 4-D (1 Mg/L). The most effective treatment on the total phenol content was yeast extract (250 ppm) in a 7-day period. HPLC for quercetin (a flavonoid component) indicated that the most effective treatment was the interaction effect of nanoAg particles (30 Mg) and yeast extract (250 Mg) in a 3-day period.
The highest amount of callus induction is obtained from the hypocotyledon explants. The best direct regeneration is recorded in the root explants. To increase total phenol, it is necessary to use yeast extracts in a 7-day period and to increase flavonoids using the interaction effect of nano-silver (30 Mg) and yeast extract (250 Mg) over a 3-day period.