The role of auxin in cell separation in the dehiscence zone of oilseed rape pods

Concentrations of both free and conjugated indole-3-acetic acid (IAA) were studied during development of pod wall, dehiscence zone and seeds of Brassica napus pods. A decrease in auxin content prior to moisture loss in the pods was observed specifically in the dehiscence zone, which was correlated w...

Full description

Saved in:
Bibliographic Details
Published in:Journal of experimental botany 1997-07, Vol.48 (7), p.1423-1429
Main Authors: Chauvaux, N., Child, R., John, K., Ulvskov, P., Borkhardt, B., Prinsen, E., Van Onckelen, H.A.
Format: Article
Language:English
Subjects:
Abscission
Agronomy. Soil science and plant productions
auxin
Auxins
Biological and medical sciences
Brassica napus
Cell separation
Cell walls
cellulase
Dehiscence
Economic plant physiology
Enzymes
Flowering
Fructification and ripening
Fructification, ripening. Postharvest physiology
Fundamental and applied biological sciences. Psychology
Growth and development
Oilseeds
Plant physiology and development
pod dehiscence
Regulation of Growth, Development and Whole Organism Physiology
Seed pods
Seeds
Vegetative and sexual reproduction, floral biology, fructification
Citations: Items that cite this one
Online Access:Get full text
Tags: Add Tag
No Tags, Be the first to tag this record!
Description
Summary:Concentrations of both free and conjugated indole-3-acetic acid (IAA) were studied during development of pod wall, dehiscence zone and seeds of Brassica napus pods. A decrease in auxin content prior to moisture loss in the pods was observed specifically in the dehiscence zone, which was correlated with a tissue specific increase in β-1,4-glucanase activity. Furthermore, treatment of the pods with the auxin mimic 2-methyl-4-chlorophenoxyacetic acid resulted in a delay of 10 d of β-1,4-glucanase activity and con-comitant cell separation in the dehiscence zone. This indicates that the activity of hydrolytic enzymes involved in cell separation in the dehiscence zone is regulated by auxin activity. Comparison of parthenocarpic pods with seeded pods pointed to the seeds as the source of IAA. Levels in the dehiscence zone of these pods were low over the entire sampling period, while cell separation in the dehiscence zone was delayed by about 4 d. These results indicate that a low level of auxins in the dehiscence zone is necessary for dehiscence to take place, but other factors may also be important.
ISSN:0022-0957
1460-2431
DOI:10.1093/jxb/48.7.1423