Stem Anatomy and Adventitious Root Formation in Cuttings of Angophora, Corymbia and Eucalyptus

Forests

Philippa H. Bryant¹  Stephen J. Trueman¹  Fei-Hai Yu² 

[1] Genecology Research Centre, University of the Sunshine Coast, Maroochydore DC, QLD 4558, Australia;id="af1-forests-06-01227">1Genecology Research Centre, University of the Sunshine Coast, Maroochydore DC, QLD 4558, Austral

关键词: auxin;    clonal forestry;    eucalypts;    morphology;    nursery;    propagation;    rooting;    tissue culture;   

DOI  :  10.3390/f6041227

来源: mdpi

【 摘 要 】

Many plantation eucalypts are difficult to propagate from cuttings, and their rooted cuttings often possess very few adventitious roots. We microscopically examined the stem anatomy of cuttings from 12 species of eucalypts and we determined whether adventitious root formation in auxin-treated cuttings of four species was limited to particular positions around the vascular tissue. Most species contained a central pith that was arranged in a four-pointed stellate pattern. The surrounding vascular tissue was also arranged in a stellate pattern near the shoot apex but it developed a more rectangular shape at the outer phloem as the stems enlarged radially. Adventitious roots formed at, or slightly peripheral to, the vascular cambium, and they formed at both the corners and the sides of the rectangular-shaped vascular tissue. The study highlighted that auxin-treated eucalypt cuttings can produce roots at multiple positions around the vascular tissue and so propagation methods can aim to produce more than four adventitious roots per rooted cutting. Higher numbers of adventitious roots could improve the root system symmetry, stability, survival and growth rate of clonal eucalypt trees.

【 授权许可】

CC BY   
© 2015 by the authors; licensee MDPI, Basel, Switzerland.