Abstract
Brassinosteroids are steroidal lactones of plant origin that promote growth of a number of plant systems, and particularly the growth induced by auxins. Biologically active brassinosteroids (BR) also promote the growth of gravisensitive hypocotyls of 7-day-old light grown Phaseolus vulgaris when gravistimulated. Brassinolide-mediated promotion of curvature of gravistimulated internodes occurs in the absence of exogenously supplied indole-3-acetic acid (IAA). This is in contrast to the BR-promoted bending of vertically positioned bean hypocotyls, which is dependent upon exogenous IAA. Brassinosteroid treatment increased the graviperception of young internode tissues and the bending of the gravistimulated sections as well as the subsequent reversal of bending after the sections were placed vertically. These results indicate that BR sensitizes bean hypocotyls to gravistimulation and potentiates the action of a growth factor that induces gravitropic growth.
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- Cohen J. D., Meudt W. J. Investigations on the Mechanism of the Brassinosteroid Response: I. Indole-3-acetic Acid Metabolism and Transport. Plant Physiol. 1983 Jul;72(3):691–694. doi: 10.1104/pp.72.3.691. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Mitchell J. W., Mandava N., Worley J. F., Plimmer J. R., Smith M. V. Brassins--a new family of plant hormones from rape pollen. Nature. 1970 Mar 14;225(5237):1065–1066. doi: 10.1038/2251065a0. [DOI] [PubMed] [Google Scholar]
- Pickard B. G. Early events in geotropism of seedling shoots. Annu Rev Plant Physiol. 1985;36:55–75. doi: 10.1146/annurev.pp.36.060185.000415. [DOI] [PubMed] [Google Scholar]
- Thompson M. J., Meudt W. J., Mandava N. B., Dutky S. R., Lusby W. R., Spaulding D. W. Synthesis of brassinosteroids and relationship of structure to plant growth-promoting effects. Steroids. 1982 Jan;39(1):89–105. doi: 10.1016/0039-128x(82)90129-5. [DOI] [PubMed] [Google Scholar]