Optimization of Cell Suspension Induction in Tragacanth Astragalus (Astragalus Verus)

Astragalus verus is one of best species for tragacanth production. The aim of this study was optimization of cell suspension culture in this plant. First, the callus production was optimized then optimization of cell suspension was performed. The callus production experiment was conducted in a factorial arrangement with explants of root, hypocotyl and cotyledon in MS medium containing BAP in combination with 2,4-D and NAA. In experiment of cell suspension optimization, callus that derived from medium containing NAA and 2, 4-D were investigated using 16 hormonal treatments and three replications in a completely randomized design. Also, it was investigated the application of dark treatments, ascorbic acid, poly-vinyl pyrrolidone and EDTA iron chelate to avoid phenolic compounds. The results showed that the highest callus production percentage (average of 67%) was obtained in the medium of 2,4-D with root explant. The best hormone treatment of cell suspension was 3 mg /L 2,4-D in combination with 0.5 mg/L Kin with an average of 0.277 viability, and 0.040 g dry weight (at 5ml). In the study of the effect of browning inhibitors, the highest dry weight was obtained with 100 mg/l ascorbic acid in cell culture medium with an average of 0.76 g (at 5ml). This treatment was effective in prevention phenolic compounds. The results of this study showed that 2,4-D could be used alone for inducing proper callus and in combination with Kin for the production of cell suspension. It was also found that ascorbic acid can well control the process of browning cells of cell suspension. The results of this study can be used for in vitro tragacant production.