Ephemeral root modules in Fraxinus mandshurica

Détails bibliographiques
Publié dans:	The New phytologist. - 1990. - 188(2010), 4 vom: 15. Dez., Seite 1065-74
Auteur principal:	Xia, Mengxue (Auteur)
Autres auteurs:	Guo, Dali, Pregitzer, Kurt S
Format:	Article en ligne
Langue:	English
Publié:	2010
Accès à la collection:	The New phytologist
Sujets:	Journal Article Research Support, Non-U.S. Gov't Nitrogen N762921K75

Description
Résumé:	© The Authors (2010). Journal compilation © New Phytologist Trust (2010). Historically, ephemeral roots have been equated with 'fine roots' (i.e. all roots of less than an arbitrary diameter, such as 2 mm), but evidence shows that 'fine roots' in woody species are complex branching systems with both rapid-cycling and slow-cycling components. A precise definition of ephemeral roots is therefore needed. Using a branch-order classification, a rhizotron method and sequential sampling of a root cohort, we tested the hypothesis that ephemeral root modules exist within the branching Fraxinus mandshurica (Manchurian ash) root system as distal nonwoody lateral branches, which show anatomical, nutritional and physiological patterns distinct from their woody mother roots. Our results showed that in F. mandshurica, distal nonwoody root branch orders die rapidly as intact lateral branches (or modules). These nonwoody branch orders exhibited highly synchronous changes in tissue nitrogen concentrations and respiration, dominated root turnover, nutrient flux and root respiration, and never underwent secondary development. The ephemeral root modules proposed here may provide a functional basis for differentiating and sampling short-lived absorptive roots in woody plants, and represent a conceptual leap over the traditional coarse-fine root dichotomies based on arbitrary size classes
Description:	Date Completed 15.02.2011 Date Revised 30.09.2020 published: Print-Electronic Citation Status MEDLINE
ISSN:	1469-8137
DOI:	10.1111/j.1469-8137.2010.03423.x