This Article Full Text Full Text (PDF) Supplemental Data All Versions of this Article: 149/3/1452    most recent pp.108.134486v1 Alert me when this article is cited Alert me if a correction is posted Services Email this article to a friend Related articles in Plant Physiol. Similar articles in this journal Similar articles in Web of Science Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Citing Articles Citing Articles via CrossRef Citing Articles via Web of Science (1) Citing Articles via Google Scholar Google Scholar Articles by Biskup, B. Articles by Walter, A. Search for Related Content PubMed PubMed Citation Articles by Biskup, B. Articles by Walter, A. Agricola Articles by Biskup, B. Articles by Walter, A.

WHOLE PLANT AND ECOPHYSIOLOGY

Diel Growth Cycle of Isolated Leaf Discs Analyzed with a Novel, High-Throughput Three-Dimensional Imaging Method Is Identical to That of Intact Leaves^1,[W]

Institute of Chemistry and Dynamics of the Geosphere ICG-3 (Phytosphere), Forschungszentrum Jülich GmbH, 52425 Jülich, Germany

Dicot leaves grow with pronounced diel (24-h) cycles that are controlled by a complex network of factors. It is an open question to what extent leaf growth dynamics are controlled by long-range or by local signals. To address this question, we established a stereoscopic imaging system, GROWSCREEN 3D, which quantifies surface growth of isolated leaf discs floating on nutrient solution in wells of microtiter plates. A total of 458 leaf discs of tobacco (Nicotiana tabacum) were cut at different developmental stages, incubated, and analyzed for their relative growth rates. The camera system was automatically displaced across the array of leaf discs; visualization and camera displacement took about 12 s for each leaf disc, resulting in a time interval of 1.5 h for consecutive size analyses. Leaf discs showed a comparable diel leaf growth cycle as intact leaves but weaker peak growth activity. Hence, it can be concluded that the timing of leaf growth is regulated by local rather than by systemic control processes. This conclusion was supported by results from leaf discs of Arabidopsis (Arabidopsis thaliana) Landsberg erecta wild-type plants and starch-free1 mutants. At night, utilization of transitory starch leads to increased growth of Landsberg erecta wild-type discs compared with starch-free1 discs. Moreover, the decrease of leaf disc growth when exposed to different concentrations of glyphosate showed an immediate dose-dependent response. Our results demonstrate that a dynamic leaf disc growth analysis as we present it here is a promising approach to uncover the effects of internal and external cues on dicot leaf development.

The author responsible for distribution of materials integral to the findings presented in this article in accordance with the policy described in the Instructions for Authors (www.plantphysiol.org) is: Hanno Scharr (h.scharr{at}fz-juelich.de).

^[W] The online version of this article contains Web-only data.

www.plantphysiol.org/cgi/doi/10.1104/pp.108.134486

^* Corresponding author; e-mail a.walter{at}fz-juelich.de.

Received December 17, 2008; accepted January 12, 2009; published January 23, 2009.

Related articles in Plant Physiol.:

On the Inside

Peter V. Minorsky
Plant Physiol. 2009 149: 1205-1206. [Full Text]