Comparison micropropagated Sorbus aucoparia plantlets in photoautotrophic and semi-photoautotrophic conditions

Sorbus aucoparia is an important forest tree from Sorbus genus in Rosaceae family. it is an important medicinal, industrial and ornamental plant. Sorbus aucoparia is potentially useful for reforestration in high altitude. This species is one of the endangered species of northern forests of Iran. Micropropagation of adult trees by bud culture helps to conserve this valuable species. In this study, proliferation of Sorbus aucoparia with photoautotrophic (artification CO2 nutrition) and semi- photoautotrophic (use of accumulated proliferation around containers in growth chamber) condition was performed. Shoots of tissue cultured plantlets from mature trees, were used as explants. Explants were cultured on DKW medium supplemented with or without sucrose, agar and vermiculite for six weeks, in Magenta (G7) containers. containing. Gas exchange rate of culture containers under photoautotrophic and semi- photoautotrophic conditions were caculated. Results showed, Shoot hight, shoot and bud numbers, dry weight, leaf number, leaf area, chlorophyl quantity, rooting percent and leaf greenish under photoautotrophic conditions have significant difference with semi- photoautotrophic conditions. These findings suggested that, photoautotrophic technique is moreapplicable method than semi- photoautotrophic technique for micropropagation of Sorbus aucoparia.