SOMATIC EMBRYOGENESIS AND PLANT-REGENERATION IN DIFFERENT ORGANS OF EUTERPE EDULIS MART. (PALMAE) - CONTROL AND STRUCTURAL FEATURES

Somatic embryogenesis and further plant regeneration were observed usi ng zygotic embryos, young inflorescences and young leaves of Euterpe e dulis (Palmae) as explants, Both for the cultures of zygotic embryos a nd inflorescences, activated charcoal in the medium was essential for the establishment of viable cultures, Embryogenesis was induced by usi ng a gelled basal medium with MS or Euwens salts supplemented by high 2, 4-D levels (50-100 mg L-1), The embryogenic process was direct with out a callus stage. For further development, cultures with globular or postglobular embryos were transferred to the basal medium with 2-iP ( 2,5 mg L-1) and NAA (0.1 mg L-1.) To convert embryos to plantlets, cul tures were transferred to a third medium in which sucrose and salts we re reduced to the half-strenght of the basal medium, without growth re gulators. In the case of leaves, cultures were initiated on filter pap er bridges on a liquid medium, with either 2, 4-D or NAA (10-20 mg L-1 ). The developmental stage of each explant was critical for the induct ion of embryogenesis. The histological study of embryogenic cultures r evealed that in the case of zygotic embryos, somatic embryos arise dir ectly from the surface of the cotyledonar node, or from subepidermal t issues. In the inflorescences, a pro-embryogenic tissue is formed at t he floral primordium region;in the leaves, the first morphogenic event is cell proliferation in the vascular parenchyma.