Influence of 2,3,5-Triiodobenzoic Acid and 1-N-Naphthylphthalamic Acid on Indoleacetic Acid Transport in Carnation Cuttings: Relationship with Rooting |
| |
Authors: | J R Guerrero G Garrido M Acosta J Sánchez-Bravo |
| |
Institution: | (1) Departamento de Biología Vegetal, Facultad de Biología, Universidad de Murcia, 30100, Murcia, Spain, ES |
| |
Abstract: | 3H-IAA transport in excised sections of carnation cuttings was studied by using two receiver systems for recovery of transported
radioactivity: agar blocks (A) and wells containing a buffer solution (B). When receivers were periodically renewed, transport
continued for up to 8 h and ceased before 24 h. If receivers were not renewed, IAA transport decreased drastically due to
immobilization in the base of the sections. TIBA was as effective as NPA in inhibiting the basipetal transport irrespective
of the application site (the basal or the apical side of sections). The polarity of IAA transport was determined by measuring
the polar ratio (basipetal/acropetal) and the inhibition caused by TIBA or NPA. The polar ratio varied with receiver, whereas
the inhibition by TIBA or NPA was similar. Distribution of immobilized radioactivity along the sections after a transport
period of 24 h showed that the application of TIBA to the apical side or NPA to the basal side of sections, increased the
radioactivity in zones further from the application site, which agrees with a basipetal and acropetal movement of TIBA and
NPA, respectively. The existence of a slow acropetal movement of the inhibitor was confirmed by using 3H-NPA. From the results obtained, a methodological approach is proposed to measure the variations in polar auxin transport.
This method was used to investigate whether the variations in rooting observed during the cold storage of cuttings might be
related to changes in polar auxin transport. As the storage period increased, a decrease in intensity and polarity of auxin
transport occurred, which was accompanied by a delay in the formation and growth of adventitious roots, confirming the involvement
of polar auxin transport in supplying the auxin for rooting.
Received April 19, 1999; accepted December 2, 1999 |
| |
Keywords: | ,Dianthus caryophyllus—,Indoleacetic acid—,Naphthylphthalamic acid—,Polar auxin transport—,rooting of cuttings—,Triiodobenzoic,,,,,acid |
本文献已被 PubMed SpringerLink 等数据库收录! |
|