Stimulation of carrot somatic embryogenesis by proline and serine

Abstract

Serine and proline, when added in a wide range of concentrations to Daucus carota cultures during pre-growth in the presence of 2,4-D(2,4-dichlorophenoxyacetic acid), extended in time and quantity the mitotic divisions and stimulated significantly the number of embryos regenerated when the hormone subsequently was omitted from the medium. A specific effect of these amino acids on regeneration is suggested, since proline (as hydroxyproline) and serine are the two major constituents of the cell wall glycoprotein, extensin, which thus may have a morphoregulatory function. The significant role of the conditions during pregrowth of the cultures in the presence of hormone is underlined by the effect of hydroxyproline and D-proline which also stimulate embryogenesis, but alter markedly the development of the embryos.

Improvement of somatic embryogenesis in zonal geranium

“…Somatic embryo induction utilizing 5.13 mM glutamine and GCM was near optimum (Marsolais et al, 1991). Proline is also more effective in promoting embryogenesis in geranium (Marsolais et al, 1991) and a number of other species (Armstrong and Green, 1985;Ronchi et al, 1984;Skokut et al, 1985;Stuart and Strickland, 1984b). For geranium (Marsolais et al, 1991), proline was added as the sole reduced nitrogen source.…”

Culture of Zygotic Embryos

“…Glutamine was reported being the best by many authors. Recently other amino acids, such as proline and serine were tested and it was shown that they stimulated somatic embryo growth [70]. Sometimes, inorganic nitrogen such as ammonium sulfate can produce growth increments of the embryo of the same magnitude as those observed on embryos growing in a mixture of amino acids [71].…”

Leucine and spermidine enhance shoot differentiation in cucumber (Cucumis sativus L.)

“…Similarly, the role of amino acids in plant regeneration and somatic embryogenesis is known to a considerable extent (Ronchi et al 1984;Chowdhry et al 1993), and small changes in amino acid content evoke various morphogenic responses in an in vitro culture (Dey et al 1998). Muyuan et al (1990) reported increased frequency of differentiation and the percentage of green plant regeneration in Hordeum vulgare callus in a Murashige and Skoog (MS) medium supplemented with amino acids such as alanine, asparagines, and glutamine.…”