Origin and Development In Vitro of Shoot Buds and Somatic Embryos from Intact Roots of Helianthus annuus × H. tuberosus

Ectopic structures on roots of Helianthus annuus � H. tuberosus

A variant clone of Helianthus annuus � H. tuberosus that develop �root buds� and somatic embryos from intact adventitious roots of in vitro grown plantlets is described by Fambrini et al. (pp. 145-151). These ectopic structures are initiated without exogenous hormonal treatments. Histological analysis demonstrates that they originate from cortical cells in association with the development of lateral root primordia.