In vitro plant regeneration from somatic tissue of strawberry Fragaria x ananassa Duch.

Successful shoot regeneration in somatic tissue is the basic requirement for in vitro induction of genetic variability as the new tool in plant breeding. Somatic tissue excised from in vitro multiplied strawberry plants were tested on ability for plant regeneration. Leaves, petiole and stipules were inoculated on initial medium with BA and 2,4-D, or on medium with BA only after 1 hour pulse treatment with 2,4-D. Callus was induced on all sliced surfaces of explants inoculated on initial medium with growth regulators BA and 2,4-D during first 7 days of culture. Explants inoculated on initial medium with BA, after pulse treatment with 2,4-D did not develop callus but abundantly produced fenolic compounds, and tured necrotic in the first 24 hours. Spontaneous plant regeneration was noticed on leaves explants with less developed callus tissue on initial medium with growth regulators duringsecond week of culture. High percentage of explants with regenerated shoots were obtained after transfer on hormone-free medium. The highest plant regeneration ability was in leaf tissue, less in petiole and stipules. Callus induced in leaf tissue showed ability for constant plant regeneration during three months of culture and careful 4-week interval transfer on basal MS medium with 4.4¼M BA and 40 g/l sucrose.