Involvement of indole-3-acetic acid in the circadian growth of the first internode of Arabidopsis.

摘要: The extension rate of the first inflorescence node Arabidopsis was measured during light/dark or continuous light exposure and found to exhibit oscillations which showed a circadian rhythmicity. Decapitation induced strong inhibition stem extension. Subsequent application IAA restored growth associated extension-rate oscillations. In addition, treatments, after decapitation, re-established rhythmicity visible in intact plants free run. This indicates that upper zone has major influence on floral stems implies role for auxin. Application N-(1-naphthyl)phthalamic acid, an transport inhibitor, inhibited oscillations, indicating polar may play dynamics elongation. Furthermore, IAA-aspartate application, did not restore Nevertheless, biochemical analysis demonstrated fluctuations endogenous levels both compounds. These observations suggest metabolism is essential factor regulation rhythm stems.