Conditioning of the Culture Medium by Suspension Cells and Formation of Somatic Proembryo in Araucaria angustifolia (Coniferae)

• Published in: In vitro cellular & developmental biology. Plant 2000-05, Vol.36 (3), p.194-200
• Main Authors: Leandro V. Astarita, Guerra, Miguel P.
• Format: Article
• Language: English
• Subjects: Agronomy. Soil science and plant productions; Araucaria angustifolia; Biological and medical sciences; Cell culture techniques; Cell growth; Cellular differentiation; Coniferae; Cultured cells; Daughter cells; Delta cells; Developmental Biology/Morphogenesis; Economic plant physiology; Embryonic cells; Fundamental and applied biological sciences. Psychology; In vitro culture; Mother cells; Plant cells; Plant physiology and development; Plants; Tissue cultures, protoplasts
• ISSN: 1054-5476; 1475-2689
• DOI: 10.1007/s11627-000-0036-0

Cell masses of Araucaria angustifolia cultured in LP liquid medium showed different uptake and utilization patterns for different sugars. Fructose was slowly utilized by cell growth during the lag phase. After this lag period, fructose concentration decreased quickly, corresponding to the start of linear growth. Glucose rapidly decreased following fructose depletion. The level of extracellular proteins in the culture medium increased for the first 5 d after cell inoculation, during the transition from the lag phase to the high-growth phase. The pH of the medium decreased through the first half of the culture period (4.94) and increased (5.6) thereafter. Proembryos originated from a single cell, without a cleavage process. Suspensor cells and proembryonal groups developed independently. Only embryogenic cells divided and formed a suspensor or a proembryo group, which differentiated further along the longitudinal axis. The pathway observed for proembryo formation in Araucaria differs from the model proposed for other conifers, which show cleavage polyembryony.