Plant regeneration from different explants in Helianthus smithii Heiser.

Leaf, rhizome, and stem explants of Helianthus smithii, a wild relative of the cultivated sunflower, have been tested for their morphogenic potential on media containing a range of hormonal combinations including α-naphthaleneacetic acid and 6-benzylaminopurine (0-2 mg/l). Somatic embryos appeared on the majority of the tested media incorporating auxins, while shoots were observed on media containing exclusively 6-benzylaminopurine. Fertile plants were recovered from all explant types under a wide range of conditions, albeit with different efficiencies. The induction mechanism of the observed shoots is discussed.