ISSN:
1432-203X
Keywords:
Walnut cotyledon
;
Adventitious root formation
;
Tissue culture
;
Histological investigation
;
Auxin treatment
Source:
Springer Online Journal Archives 1860-2000
Topics:
Biology
Notes:
Summary Rapid formation of adventitious roots by walnut cotyledon fragments in vitro was traced by light microscopy. It was shown that this plant model is characterized by two major developmental processes: a) confined elongation of the cotyledon petiole caused by a limited number of cell divisions and b) formation of a morphogenetic zone around each initially wounded vascular bundle within 36 h after detachment of the embryonic axis. During the first phase of development, granular storage protein bodies dissolved, and starch grains were deposited mainly in the distal portion of the cotyledon fragments. Rapidly, new globular protein bodies were formed, and phenolic inclusions accumulated in the vacuoles of epidermal and subepidermal cells and of individual cells close to the vascular bundles. Each adventitious root was found to be in continuity with a single vascular bundle of the cotyledon petiole. A short auxin treatment suppressed the formation of large roots and induced numerous tiny rootlets dispersed all over the surface of the cotyledons.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1007/BF00232369
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