ROOTING OF MICROCUTTINGS: THEORY AND PRACTICE

• Published in: In vitro cellular & developmental biology. Plant Vol. 38; no. 5; pp. 415 - 422
• Main Author: DE KLERK, GEERT-JAN
• Format: Journal Article
• Language: English
• Published: Wallingford CABI Publishing 01.09.2002; Cambridge University Press; Springer Nature B.V
• Subjects: Acclimatization; acid; Adventitious roots; aerial organs; Agronomy. Soil science and plant productions; apple microcuttings; Auxins; Biological and medical sciences; cultivated invitro; Economic plant physiology; fragments; Fundamental and applied biological sciences. Psychology; In vitro culture; micropropagated plants; pericyclic topipotency; Plant physiology and development; Plant roots; Plants; Pluripotent stem cells; Regeneration; Rooting; rorippa-sylvestris; Stem cells; stem slices; Tissue cultures, protoplasts; Totipotent stem cells; Vegetals; Auxin; Growth; Ethylene; Rejuvenation; Micropropagation; Growth regulator treatment; Review; Microcutting; Organogenesis; Regeneration; Plant growth substance; Adventitious root; Rooting
• ISSN: 1054-5476; 1475-2689
• DOI: 10.1079/IVP2002335

Poor adventitious root formation is a major obstacle in micropropagation and in conventional propagation. This paper reviews recent progress in the understanding of adventitious root formation as a developmental process focusing on the role of plant hormones and on the effect of rooting conditions on plant performance. Since the discovery of the rhizogenic effect of auxin ca. 70 yr ago, no new broadly applicable rooting treatments have been developed. Recent research, though, may lead to new rooting procedures. Application of wounding-related compounds may be effective in difficult-to-root crops. Furthermore, by adapting conditions during the propagation phase, microcuttings with an enhanced capability to root may be produced. These conditions include elongation of stems (by etiolation or double-layer culture) and repeated subculture (rejuvenation; i.e., transition from adult to juvenile). Data are presented that show that during tissue culture maturation (transition from juvenile to adult) also occurs. The conditions during the in vitro rooting treatment may have a tremendous effect on performance after transfer ex vitro. In particular, accumulation of ethylene during in vitro rooting may have a devastating effect. Addition of stress-protecting compounds during propagation or rooting in vitro may enhance the performance ex vitro.