JWSS - Journal of Water and Soil Science

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Potato is a valuable plant as a source of nutrition and as an industrial product. The modification and breeding of potato plants are very difficult, or even impossible, via the conventional plant breeding programs. However, plant biotechnology and tissue culture are reliable methods which can produce plant material for gene transformation using Agrobacterium as a vector. In this study, one-, two-, and three-step methods of plant regeneration from stem culture of potato cv. Delaware were tested. Among these only the one-step procedure using TDZ, a synthetic cytokinin, was the best for rapid plant regeneration. In this culture medium, several shoot buds and shoots were regenerated from stem culture, while the other methods using a culture medium supplemented with BAP, NAA, zeatin, 2ip, IAA produced white and green callus. Morphology and chromosome number of all regenerated plants were similar to the original plants. The results showed that the regeneration system was suitable for cv. Delaware and that the culture conditions prevented genetic variation of the regenerated plants.

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In this research the effect of ethinyl estradiol on somatic embryogenesis of Medicago sativa was investigated. Seeds were grown in vitro on MS medium containing 2,4-D, Kin and NAA for callus induction. Plant regeneration media with 14 different combinations of auxin, cytokinin and ethinyl estradiol were provided. Three to four-week old celli and stem or hypocotyl segments of Medicago sativa were transferred to regeneration media. Results showed that ethinyl estradiol (l mg/L) induced shoot, root and somatic embryo on calli. When the stem and hypocotyl segments were cultured on medium M12, only shoots and roots were produced with no somatic embryo. Finally, it was observed that ethinyl stradiol and auxin together could induce somatic embryogenesis and plant regeneration, while these hormones had no effect separately.