Effects of different BAP and NAA concentrations on micropropagation of Crambe orientalis L. var Orientalis L.

Crambe L. is a species of Brassicaceae family. It is an important industrial oil plant in respect to its high amount of erusic acid. The micropropagation of Crambe orientalis L. var. orientalis L. has not been studied yet. The aim of this thesis is to develop an efficient micropropagation protocol for Crambe orientalis L. var. orientalis L. species by using different concentrations of BAP (6-benzylaminopurine) – NAA (α-naphthalene acetic acid) hormone combinations. The seeds of Crambe orientalis var. orientalis were germinated in vitro. Cotyledon node and hypocotyl parts from fourteen-days seedlings were used as explant sources. The explants were cultured on MS media containing 0.25, 0.50, 1.00 and 2.00 mg/L BAP and 0, 0.25 and 0.50 mg/L NAA (12 different combinations). The effects of hormone concentrations on the mean callus regeneration percentage (%), on the mean shoot regeneration percentage (%), on the mean number of shoots per explant and on the mean length of shoots are determined. Callus formation resulted in all the hormone concentrations we used for our hypocotyl explants, and the mean callus regeneration percentage was between 67.87 % and 1.22 %. The shoot regeneration from hypocotyl explants formed on all hormone concentrations we used, and the mean shoot regeneration percentage was high, ranging between 44.49 % and 95.67 %. The most productive medium in respect to shoot regeneration is the MS medium containing 1.00 mg/L BAP + 0.25 mg/L NAA hormone combination with 95.67 % shoot regeneration rate. The mean number of shoots per explant for our hypocotyl explants varied between 6.02±0.68 and 27.34±0.69. The highest mean shoot number per explant was on MS medium containing 1.00 mg/L BAP + 0.25 mg/L NAA with 27.34±0.69 shoots per explant. The mean shoot length for our hypocotyl explants varied between 3.12±1.24 cm and 7.54±0.62 cm, and the highest shoot length was 7.54±0.62 cm that was seen on MS medium containing 1.00 mg/L BAP. Callus formation resulted in all the hormone combinations we used for our cotyledon nodes, and the callus regeneration percentage was between 1.76 % and 51.64 %. The shoot regeneration from cotyledon node explants formed on all hormone concentrations we used, and the mean shoot regeneration percentage was high, ranging between 49.71 % and 73.17 %. The most productive medium in respect to shoot regeneration is the MS medium containing 1.00 mg/L BAP + 0.25 mg/L NAA hormone combination with 73.17 % shoot regeneration rate. The mean number of shoots per explant for our cotyledon node explants varied between 6.12±0.98 and 18.14±1.36. The highest mean shoot number per explant was on MS medium containing 2.00 mg/L BAP + 0.25 mg/L NAA with 18.14±1.36 shoots per explant. The mean shoot length for our hypocotyl explants varied between 2.66±1.66 cm and 5.64±2.01 cm, and the highest shoot length was seen on MS medium containing 2.00 mg/L BAP with 5.64±2.01 cm. When the hypocotyl explants were compared with the cotyledon node explants, we demonstrated that the hypocotyl explants are more efficient sources of explants than cotyledon node explants. Regenerated shoots were rooted on MS media containing 0.50, 1.00 and 2.00 mg/L NAA. The rooting ratios were 21.78 %, 34.46 % and 41.32 % respectively. We determined that the rooting of regenerated shoots was generally difficult. The best rootings resulted on MS media containing 2.00 mg/L NAA.