Morphogenesis

Rice (Oryza sativa L. cultivar Pusa Basmati-1) cultures initiated from mature caryopses were used to study the pathway of morphogenesis. Histological analysis revealed almost all the stage of somatic embryogenesis. In the initial stage of development, scutellum swelled and callus was formed that contained embryogenic cells on the periphery and parenchymatous cells in the internal region. Embryogenic cells underwent a series of organised divisions and formed proembryos that further developed into globular somatic embryos with suspensor. There was no apparent vascular connection between the developing embryos and mother tissue. The embryos further developed into heart-shaped and ultimately into bipolar embryos. Fully developed somatic embryos resembled zygotic embryos with coleoptile and scutellum. Development of secondary somatic embryos from the scutellum of primary somatic embryos was also observed.