High frequency plant regeneration from microspore-derived embryos of ornamental kale (Brassica oleracea L. var. acephala)

The aim of this work was to study the effect of solid medium, developmental stage, embryonic age, cold treatment and additives to the medium on plant regeneration from microspore-derived embryos in four F1 hybrids of ornamental kale (Brassica oleracea L. var. acephala). The results showed that all of the cultivars responded best when the embryos were cultured in solidified B5 medium with 1% agar. Optimal regeneration was gained when cotyledonary embryos were cultured for 25 days. Cold treatment significantly improved plant regeneration with a frequency of up to 79.0% under 4 °C for 2 d or 5 d. The addition of 3.0 or 5.0 mg/L silver nitrate (AgNO3) increased the frequency of plant regeneration. In the Zhouyehongxin cultivar, the frequency of plantlet development reached 84.4%. The addition of activated charcoal reduced embryo hyperhydricity.

► Ornamental kale is an important ornamental foliage plant.
► We have improved the culture technology for plant regeneration from microspores embryos in kale.
► Vitrification and browning were obviously alleviated by improving method.
► An optimized high-frequency regeneration system of microspore-derived embryos was established.