Controlling Secondary Somatic Embryogenesis in Persian Oak (Quercus brantii L.) Using Hormonal Compounds and Media

Using immature embryos that undergo somatic embryogenesis, we studied the effects of different hormonal compounds and media on controlling secondary somatic embryogenesis (SSE) in Persian oak (Quercus brantii L.). To this end, we focused on the immature embryos that were subjected to several treatments including chilling (at 4 ℃) period and SH, MS, 2,4-D, IBA, BAP, and glutamine concentrations in 5 separate sequential experiments. The results showed that, by extending chilling period to 8-weeks, SSE induction was reduced (68.75%). In different MS concentrations or MS containing PGRs, the lowest globular embryo (66%) and the secondary embryo induction (87.5%) were observed in embryos treated with MS+IBA+BA. Adding 0.75 mg L-1 glutamine to MS resulted in a decrease in the secondary somatic embryogenesis (56.25%). Among MS and SH media, 1/2 SH almost entirely controlled this phenomenon (6.25%). The highest maturation progression was obtained in the SH+glutamine treatment, which had the highest conversion to plantlet percentage (100%) and vigor index of plantlets (51.93) compared to the use of SH alone. We found that nutrient and PGR concentration were critical in embryo maturation and conversion percentage and stop the embryo induction cycle that plays a major role in secondary embryogenesis.