In vitro pollination of isolated ovules of sunflower [Helianthus annuus L.]

A model system for in vitro self-pollination of isolated sunflower (Helianthus annuus L.) ovules was developed. The pollinated ovules were cultured on modified MS medium supplemented with 3% sucrose, glycine, casein hydrolysate, and growth regulators including indole-3-acetic acid (IAA), kinetin (KIN) and gibberellic acid (GA3). The frequency of developed seedlings and dissected embryos after in vitro pollination was rather low, 2.2% and 2.3%, respectively. Gynogenic seedlings were not produced in culture of unpollinated ovules. Embryological study revealed abnormalities in embryo and endosperm development after in vitro pollination. In vitro culture did not stimulate egg cell induction or autonomous endosperm development in unpollinated ovules cultured on the same media.