Please use this identifier to cite or link to this item:

Title: Tracking biochemical changes during adventitious root formation in olive (Olea europaea L.)
Authors: Porfírio, S.
Calado, M. L.
Noceda, C.
Cabrita, M. J.
Azadie, P.
Paixe, A.
Keywords: Indole-3-acetic acid (IAA)
Indole-3-butyric acid (IBA)
Oxidative enzymes
Salicylhydroxamic acid (SHAM)
Phenylpropanoid biosynthetic pathway
Issue Date: 6-Apr-2016
Publisher: Elsevier
Citation: Porfírio, S., Calado, M.L., Noceda, C., Cabrita, M.J., da Silva, M.G., Azadie, P., Peixe, A.(2016)Tracking biochemical changes during adventitious root formation in olive (Olea europaea L.), Scientia Horticulturae, 204, 41–53
Abstract: The activity of oxidative enzymes and the levels of free auxins were determined during adventitious root formation in olive explants. Rooting trials were performed both with in vitro-cultured micro shoots of the cultivar ‘Galega Vulgar’, treated with indole-3-butyric acid (IBA) and with salicylhydroxamic acid(SHAM) + IBA, as well as with semi-hardwood cuttings of the cultivars ‘Galega Vulgar’ (difficult-to-root)and ‘Cobrançosa’ (easy-to-root), treated with IBA. The auxin (IBA) was used in all experiments as a rooting promoter, while SHAM was used in micropropagation trials as rooting inhibitor, providing a negative control. Free indole-3-acetic acid (IAA) and IBA concentrations were determined in microshoots, as well as in semi-hardwood cuttings, throughout the rooting period at pre-established time-points. At the sametime-points, the enzymatic activity of polyphenol oxidases (PPO), peroxidases (POX), and IAA oxidase(IAAox) was evaluated in the microshoots. Microshoots treated with SHAM + IBA revealed higher POX and IAAox activity, as well as lower PPO activity, than those treated only with IBA. IAA levels were higher in IBA-treated microshoots during induction phase, but lower during early initiation phase. Incontrast, free IBA levels were higher in microshoots treated with SHAM + IBA during induction, but lower during initiation. A similar pattern of free auxin levels was observed in semi-hardwood cuttings of the two contrasting cultivars under evaluation. The similarities found on the auxin patterns of microshoots treated with SHAM and those of semi-hardwood cuttings of the difficult-to-root olive cultivar allow considering SHAM a reliable control for when simulation of a difficult-to-root behavior is necessary. The inhibitory effect of SHAM in root formation could be related with 1) the inhibition of alternative oxidase(AOX), leading to a down regulation of phenylpropanoid biosynthetic pathways, which would decrease the concentration of phenolic substrates for PPO; 2) an increase in IAAox activity resulting in lower free IAA levels or; 3) a defective conversion of IBA into IAA.
Type: article
Appears in Collections:FIT - Publicações - Artigos em Revistas Internacionais Com Arbitragem Científica
MED - Publicações - Artigos em Revistas Internacionais Com Arbitragem Científica

Files in This Item:

File Description SizeFormat
SciHort 204_2016_41_53.jpg2.19 MBJPEGView/OpenRestrict Access. You can Request a copy!
FacebookTwitterDeliciousLinkedInDiggGoogle BookmarksMySpaceOrkut
Formato BibTex mendeley Endnote Logotipo do DeGóis 

Items in DSpace are protected by copyright, with all rights reserved, unless otherwise indicated.


Dspace Dspace
DSpace Software, version 1.6.2 Copyright © 2002-2008 MIT and Hewlett-Packard - Feedback
UEvora B-On Curriculum DeGois