Morphological And Physiological Changes During Thidiazuron-induced Somatic Embryogenesis In Geranium (pelargonium X Hortorum Bailey) Tissue Cultures

Abstract

Somatic embryogenesis in geranium (Pelargonium x hortorum Bailey cv. 'Scarlet Orbit Improved') was achieved by culturing hypocotyls explantson media supplemented with either thidiazuron (TDZ) or indol-3-yl-acetic acid (IAA) and 6-benzylaminopurine (BAP). The physiological relationships betweenthe morphologicalchanges that lead to complete development of somatic embryos and the endogenous levels of plant growth regulators were studied. . mz induced similar but more pronounced and earlier morphological changes in cultured tissues than did IAA and BAP, but after 21 d in culture, both treatments promoted from the formation of somatic embryos of different developmental stages that were similar to zygotic induced a higher number of somatic embryos, with similar but greater increases in theendogenous levels auxins and cytokinins, than did IAA and BAP. This may indicated that TDZ may be a more potent plant growth regulator in inducing physiological and morphological changes than combined auxin and cytokinin, during the process of somatic embryogenesis in geranium