Fertile plant regeneration from sunflower ( Helianthus annuus L.) immature embryos

Abstract

We describe here a simple technique which allows the production of fertile plants from the hypocotyls of immature embryos. Immature embryos of 0.1–5 mm are incubated on a medium which slows down the development of the zygotic embryo and allows the differentiation of somatic embryo-like structures. These structures are isolated and transferred to a medium allowing development of shoots and roots. Young plantlets, transferred to soil, develop to maturity and are then self-pollinated and seed-set. This technique has been tested for six different cultivars and might be general for immature sunflower embryos. Seeds have been tested in the field and no variants have been detected suggesting that with this technique extensive somaclonal variation does not occur.