Effect of polyamines on somatic embryogenesis via mature embryo in wheat

Abstract

Plant tissue culture via somatic embryogenesis plays a key role in wheat genetic transformation studies. Therefore, the production of embryogenic calli with a high regeneration capacity is a prerequisite for efficient plant regeneration. Although immature embryos are the best type of explants for plant regeneration via somatic embryogenesis, the use of mature embryos has remarkable advantages compared to immature embryos as explants. However, the regeneration capacity of mature embryos is still lower than that of immature embryos. Plant regeneration from somatic embryos can only occur when they are mature enough. Moreover, the maturation of somatic embryos and their conversion into plantlets is closely associated with the used plant growth regulators. Polyamines are major components in the formation of somatic embryogenesis and plant regeneration. In this study, the effect of three types of polyamines on somatic embryogenesis and plant regeneration in wheat was evaluated. Although the effect of polyamines on embryogenic callus formation was not significant, their effect on responded embryogenic callus rate and plant regeneration efficiency was very significant. The highest responded embryogenic callus rate and highest regeneration efficiency were obtained on MS medium containing putrescine. Unlike other polyamines, an increase in putrescine concentration promoted a higher number of regenerated plants. The highest values for responded embryogenic callus and regeneration efficiency were determined in 1 mM concentration of putrescine. Plantlets derived from somatic embryos were successfully established in soil, producing fertile seeds.