Somatic embryogenesis and plant regeneration from immature embryos of Triticum timopheevii Zhuk. and Triticum kiharae Dorof. et Migusch, wheat species with G genome

Abstract

The efficiency of immature embryo-derived in vitro culture of G genome wheats is significantly influenced by various auxins and sugars which are used for induction of embryogenic response, and by regeneration media composition for promotion of plant development from subcultured embryogenic calli. The embryogenic calli of Triticum timopheevii has demonstrated the highest regeneration ability when the initial explants were cultured on the media supplemented with 4 mg l−1 of Picloram (29.0 %), 4 mg l−1 of Dicamba (28.7 %) or 3 mg l−1 of 2,4-D (29.1 %). The media supplemented with 5–6 mg l−1 of Picloram were considered to be the most effective for promotion of embryogenic/regenerable callus production in Triticum kiharae cultures (73.7–75.0 %). Both T. timopheevii and T. kiharae embryogenic structures were characterized by the formation of green and albino plantlets. Generally the medium that was initially supplemented with Picloram promoted the formation of lower albino plants fraction rather than 2,4-D and Dicamba. As it was measured by the total green plant production per initial explant, the overall efficiency has been reduced when sucrose was substituted by glucose or maltose. The regeneration medium supplemented with 0.25 mg l−1 TDZ significantly enhanced the regeneration capacity of embryogenic callus in T. kiharae. In culture of T. timopheevii the difference between the medium lack of growth regulators and the medium supplemented with TDZ was not prominent, though both of the media have demonstrated the greater efficacy as compared to those supplemented with BA and Zeatin.