Polyamines promote root elongation and growth by increasing root cell division in regenerated Virginia pine (Pinus virginiana Mill.) plantlets

• Published in: Plant cell reports 2005-12, Vol.24 (10), p.581-589
• Main Authors: Tang, W, Newton, R.J
• Format: Article
• Language: English
• Subjects: adventitious roots; amine oxidase (copper-containing); Amine Oxidase (Copper-Containing) - drug effects; Amine Oxidase (Copper-Containing) - metabolism; amine oxidase (flavin-containing); Biogenic Polyamines - metabolism; Biogenic Polyamines - pharmacology; Biological and medical sciences; Biotechnology; callus culture; Cell division; Cells, Cultured; Cold tolerance; culture media; Dose-Response Relationship, Drug; Enzymatic activity; enzyme activity; Eukaryotic cell cultures; Fundamental and applied biological sciences. Psychology; Low temperature; Methods. Procedures. Technologies; micropropagation; Miscellaneous; mitosis; Mitosis - drug effects; Mitosis - physiology; Mitotic Index; Oxidoreductases Acting on CH-NH Group Donors - drug effects; Oxidoreductases Acting on CH-NH Group Donors - metabolism; Pine trees; Pinus - drug effects; Pinus - growth & development; Pinus - metabolism; Pinus virginiana; plant biochemistry; Plant cells and fungal cells; plant physiology; Plant Roots - drug effects; Plant Roots - growth & development; Plant Roots - metabolism; plantlets; Polyamine Oxidase; Polyamines; putrescine; Putrescine - metabolism; Putrescine - pharmacology; Regeneration - drug effects; Regeneration - physiology; Root development; root growth; rooting; spermidine; Spermidine - metabolism; Spermidine - pharmacology; spermine; Spermine - metabolism; Spermine - pharmacology; Survival; Survival Rate; Trees; Up-Regulation - drug effects; Up-Regulation - physiology
• ISSN: 0721-7714; 1432-203X
• DOI: 10.1007/s00299-005-0021-5

Polyamines have been demonstrated to play an important role in adventitious root formation and development in plants. Here, we present a detailed analysis of influence of exogenously added polyamines on adventitious root development and its relationship to cold tolerance in Virginia pine (Pinus virginia Mill.). Our results demonstrated that polyamines putrescine (Put), spermidine (Spd), and spermine (Spm) at 0.001 mM improve rooting frequency and promote root elongation. Put, Spd, and Spm at 0.01-1 mM decrease rooting frequency and reduce root elongation root elongation. Measurements of diamine oxidase (DAO, EC 1.4.3.6) and polyamine oxidase (PAO, EC 1.4.3.4) activities showed that higher DAO and PAO enzyme activities were obtained when high concentrations of polyamines were applied and when plantlets were treated for 5-7 week at 4°C and 16°C. Survival rate of plantlets increased with the treatment of polyamines at low temperature. Polyamines increased mitotic index of cells in root tips of regenerated plantlet cultured on medium containing 0.001 micromolar Put, Spd, or Spm, but did not increase mitotic index in tissues of needle tips of the same plantlets. These results demonstrated that polyamines promote root elongation and growth by increasing root cell division in regenerated Virginia pine plantlets.