HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS		QUICK SEARCH:   [advanced] Author: Keyword(s): Year:  Vol:  Page:

First published online November 7, 2008; doi:10.3732/ajb.0800092 American Journal of Botany 95: 1506-1514 (2008) © 2008 Botanical Society of America, Inc.

What's this?

This Article Full Text Full Text (PDF) All Versions of this Article: ajb.0800092v1 95/12/1506    most recent Submit a response Alert me when this article is cited Alert me when eLetters are posted Alert me if a correction is posted Services Email this article to a friend Similar articles in this journal Alert me to new issues of the journal Download to citation manager Citing Articles Citing Articles via HighWire Citing Articles via Google Scholar Google Scholar Articles by Valenzuela-Estrada, L. R. Articles by Eissenstat, D. M. Search for Related Content PubMed Articles by Valenzuela-Estrada, L. R. Articles by Eissenstat, D. M. Agricola Articles by Valenzuela-Estrada, L. R. Articles by Eissenstat, D. M. Social Bookmarking                            What's this?

Root anatomy, morphology, and longevity among root orders in Vaccinium corymbosum (Ericaceae)¹

² Department of Horticulture, The Pennsylvania State University, University Park, Pennsylvania 16802 USA

ABSTRACT

Understanding root processes at the whole-plant or ecosystem scales requires an accounting of the range of functions within a root system. Studying root traits based on their branching order can be a powerful approach to understanding this complex system. The current study examined the highly branched root system of the ericoid plant, Vaccinium corymbosum L. (highbush blueberry) by classifying its root orders with a modified version of the morphometric approach similar to that used in hydrology for stream classification. Root anatomy provided valuable insight into variation in root function across orders. The more permanent portion of the root system occurred in 4th- and higher-order roots. Roots in these orders had radial growth; the lowest specific root length, N:C ratios, and mycorrhizal colonization; the highest tissue density and vessel number; and the coarsest root diameter. The ephemeral portion of the root system was mainly in the first three root orders. First- and 2nd-order roots were nearly anatomically identical, with similar mycorrhizal colonization and diameter, and also, despite being extremely fine, median lifespans were not very short (115–120 d; estimated with minirhizotrons). Our research underscores the value of examining root traits by root order and its implications to understanding belowground processes.

Key Words: blueberry • Ericaceae • minirhizotrons • mycorrhizas • root architecture • root form • root function • root lifespan • Vaccinium corymbosum

Received for publication 11 March 2008. Accepted for publication 22 September 2008.

FOOTNOTES

¹ The authors thank R. Haldeman and M. Hazen from the Electron Microscopy facility at Penn State for technical support in fixing, embedding, and sectioning roots; C. McKernan, A. Valenzuela-Estrada, and H. Xu for technical assistance in collecting, dissecting, and measuring roots; and J. Sharda and M. Zadworny for guidance in clearing and staining roots to assess mycorrhizal colonization. They also appreciate support from R. Koide, K. Demchak, and E. Sánchez for helpful reviews and help with maintaining experimental field plots. This research was supported by grants from the National Science Foundation (IOB- 06-13832). L.R.V.-E. received financial support from the Consejo Nacional de Ciencia y Tecnología (CONACYT) of Mexico. V.V.-C, was supported by NSF REU with additional support from the Student Research Opportunities Program (SROP).

³ Author for correspondence (e-mail: dme9{at}psu.edu)

CiteULike    Complore    Connotea    Del.icio.us    Digg    Facebook    Reddit    Technorati    Twitter    What's this?

This article has been cited by other articles:

				L. R. Valenzuela-Estrada, J. H. Richards, A. Diaz, and D. M. Eissensat Patterns of nocturnal rehydration in root tissues of Vaccinium corymbosum L. under severe drought conditions J. Exp. Bot., March 1, 2009; 60(4): 1241 - 1247. [Abstract] [Full Text] [PDF]