Action de la 5-bromouracile et de ses nucléosides sur la morphogénèse des boutures de plantules étiolées de Tomate

✍ Scribed by A. Guillot

• Publisher: Springer-Verlag
• Year: 1971
• Tongue: English
• Weight: 638 KB
• Volume: 97
• Category: Article
• ISSN: 0032-0935
• DOI: 10.1007/bf00389207

✦ Synopsis

Bromouracil and its Nueleosides on the Morphogenesis of the Cuttings of Etiolated Tomato Seedlings Summary. 1. 5-Bromouracil inhibits the growth of the hypocotyl and the rhizogenesis in the cuttings of etiolated tomato seedlings only at high concentrations. 5-Bromouridine is inactive, but 5-bromodeoxyuridine strongly inhibits both phenomena.

2. The inhibition induced by 5-bromouracil cannot be reversed by thymine, deoxythymidine, uracil, uridine or fl-alanine, a catabolic product of uracil.

3. Deoxythymidine is the one pyrimidine nueleoside which reverses the inhibition of growth and rhizogenesis brought about by 5-bromodeoxyuridine.

4. Deoxycytidine enhances the inhibition of rhizogenesis caused by 5-bromodeoxyuridine. Such an effect on the growth of the hypocotyl is not observed.

5. Taking into consideration the data in the literature, it is concluded: a) 5-bromouracil can act in several ways which possibly differ according to the plant species: in some instances (as in the ease described here), it seems to act by a mechanism unconnected with the metabolism of pyrimidine nucleic bases: b) 5-bromodeoxyuridine is a specific antimetabolite of deoxythymidine, but other metabolic interactions exist between 5-bromodeoxyuridine and deoxyeytidine, each of the latter substances probably acting as a modifier of the metabolism of the other.