androgenesis, anther culture, isolated microspore, microsporogenesis, ploidy, red beet
Abstract
So far there is no information about receiving red beet androgenic embryos by androgenesis. Several factors were tested which affected this process: starch accumulation in microspores, correlation between bud length and microsporogenesis course, induction and regeneration medium composition. Ploidy level of obtained regenerants were evaluated. Treating anthers with α-amylase or watering donor plants with gibberellin increased number of obtained androgenic embryos. The highest percentage (80%) of microspores at uninuclear stage appeared in buds with 1.3-1.5 mm. The B5 medium with 100 g·L-1 sucrose and 0.1 mg·L-1 2,4-D (2, 4-dichlorophenoxyacetic acid) proved to be better for inducing androgenesis than MS medium supplemented with 0.2 mg·L-1 BAP (6-benzylaminopurine) and 0.5 mg·L-1 IAA (indole-3-acetic acid). First androgenic embryos were placed on B5 medium without plant growth regulators and then on MS medium containing 0.2 mg·L-1 BAP and 1 mg·L-1 NAA (α-naphthaleneacetic acid). Androgenic embryos died on B5 regeneration medium without plant growth regulators. On MS medium first shoots and callus with and without roots were obtained. Rosettes withered during following passages whereas callus tissue developed further. The quantity of DNA in this tissue equivalent to 4X chromosomes.
