Thidiazuron promotes in vitro regeneration of wheat and barley

Abstract

Summary Thidiazuron (TDZ) is a substituted phenylurea which has been shown to be an efficacious regulator of in vitro morphogenesis of many dicot plant species. However, information regarding the effect of TDZ on in vitro regeneration of monocot species is limited. We investigated the effects of TDZ on in vitro regeneration of barley (Hordeum vulgare L.) and wheat (Triticum aestivum L.) and found that it promoted shoot regeneration from callus in these two important cereal species. Plant regeneration from calluses derived from immature embryo culture of barley and wheat was observed in regeneration media with a wide range of TDZ concentrations (0.045‐45 mM). Shoot regeneration from barley calluses was the highest (38.3% for cv. Golden Promise) at 4.5 mM (1 mg l 21 ) TDZ, while the optimal TDZ level for wheat regeneration seemed to be 0.9 mM (0.2 mg l 21 ) (87% for cv. Bob White and 49.4% for cv. Hi-Line). Roots developed normally when the regenerated wheat and barley shoots from TDZ-containing media were transferred to the rooting medium. Comparison with other plant growth regulators commonly used in wheat and barley regeneration media suggested that TDZ was among the best for in vitro regeneration of wheat and barley.