Cargando…
Raising the pH of the Pulsing Solution Improved the Acropetal Transport of NAA and 2,4-D and Their Efficacy in Reducing Floret Bud Abscission of Red Cestrum Cut Flowers
The use of auxins to improve the vase life of cut flowers is very limited. Previous studies demonstrated that a pulse treatment of Red Cestrum (Cestrum elegans Schlecht.) cut flowers with 2,4-dichlorophenoxyacetic acid (2,4-D) significantly reduced floret bud abscission, whereas 1-naphthaleneacetic...
Autores principales: | , , , , , |
---|---|
Formato: | Online Artículo Texto |
Lenguaje: | English |
Publicado: |
Frontiers Media S.A.
2020
|
Materias: | |
Acceso en línea: | https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7327294/ https://www.ncbi.nlm.nih.gov/pubmed/32670317 http://dx.doi.org/10.3389/fpls.2020.00825 |
_version_ | 1783552510342987776 |
---|---|
author | Abebie, Bekele Philosoph-Hadas, Sonia Riov, Joseph Huberman, Moshe Goren, Raphael Meir, Shimon |
author_facet | Abebie, Bekele Philosoph-Hadas, Sonia Riov, Joseph Huberman, Moshe Goren, Raphael Meir, Shimon |
author_sort | Abebie, Bekele |
collection | PubMed |
description | The use of auxins to improve the vase life of cut flowers is very limited. Previous studies demonstrated that a pulse treatment of Red Cestrum (Cestrum elegans Schlecht.) cut flowers with 2,4-dichlorophenoxyacetic acid (2,4-D) significantly reduced floret bud abscission, whereas 1-naphthaleneacetic acid (NAA) was ineffective. This difference resulted, at least in part, from the higher acropetal transport capability of 2,4-D compared to that of NAA. The present research focused on examining the factors affecting the acropetal transport, and hence the efficacy of the two auxins in reducing floret bud abscission of Red Cestrum cut flowers. We assumed that the differential acropetal transport capability of the two auxins results from the difference in their dissociation constants (pKa), with values of 2.75 and 4.23 for 2,4-D and NAA, respectively, which affects their pH-dependent physicochemical properties. Thus, increasing the pH of the pulsing solution above the pKa of both auxins might improve their acropetal movement. Indeed, the results of the present research show that raising the pH of the pulsing solution to pH 7.0 and above improved the efficacy of the two auxins in reducing floret bud abscission, with a higher effect on 2,4-D than that on NAA. Raising the pH of the pulsing solution decreased the adsorption and/or uptake of the two auxins by the cells adjacent to the xylem vessels, leading to an increase in their acropetal transport. The high pH of the pulsing solution increased the dissociation and hence decreased the lipophilicity of the auxin molecules, leading to improved acropetal movement. This effect was corroborated by the significant reduction in their 1-octanol/water partition coefficient (K(OW)) values with the increase in the pH. A significant increase in the CeIAA1 transcript level was obtained in response to 2,4-D pulsing at pH 7.0 and 8.25 and to NAA pulsing at pH 8.25, indicating that the acropetally transported auxins were taken up by the cells under these conditions. Our data suggest that raising the pH of the pulsing solution would significantly contribute to the increased efficacy of auxins in improving the vase life of cut flowers. |
format | Online Article Text |
id | pubmed-7327294 |
institution | National Center for Biotechnology Information |
language | English |
publishDate | 2020 |
publisher | Frontiers Media S.A. |
record_format | MEDLINE/PubMed |
spelling | pubmed-73272942020-07-14 Raising the pH of the Pulsing Solution Improved the Acropetal Transport of NAA and 2,4-D and Their Efficacy in Reducing Floret Bud Abscission of Red Cestrum Cut Flowers Abebie, Bekele Philosoph-Hadas, Sonia Riov, Joseph Huberman, Moshe Goren, Raphael Meir, Shimon Front Plant Sci Plant Science The use of auxins to improve the vase life of cut flowers is very limited. Previous studies demonstrated that a pulse treatment of Red Cestrum (Cestrum elegans Schlecht.) cut flowers with 2,4-dichlorophenoxyacetic acid (2,4-D) significantly reduced floret bud abscission, whereas 1-naphthaleneacetic acid (NAA) was ineffective. This difference resulted, at least in part, from the higher acropetal transport capability of 2,4-D compared to that of NAA. The present research focused on examining the factors affecting the acropetal transport, and hence the efficacy of the two auxins in reducing floret bud abscission of Red Cestrum cut flowers. We assumed that the differential acropetal transport capability of the two auxins results from the difference in their dissociation constants (pKa), with values of 2.75 and 4.23 for 2,4-D and NAA, respectively, which affects their pH-dependent physicochemical properties. Thus, increasing the pH of the pulsing solution above the pKa of both auxins might improve their acropetal movement. Indeed, the results of the present research show that raising the pH of the pulsing solution to pH 7.0 and above improved the efficacy of the two auxins in reducing floret bud abscission, with a higher effect on 2,4-D than that on NAA. Raising the pH of the pulsing solution decreased the adsorption and/or uptake of the two auxins by the cells adjacent to the xylem vessels, leading to an increase in their acropetal transport. The high pH of the pulsing solution increased the dissociation and hence decreased the lipophilicity of the auxin molecules, leading to improved acropetal movement. This effect was corroborated by the significant reduction in their 1-octanol/water partition coefficient (K(OW)) values with the increase in the pH. A significant increase in the CeIAA1 transcript level was obtained in response to 2,4-D pulsing at pH 7.0 and 8.25 and to NAA pulsing at pH 8.25, indicating that the acropetally transported auxins were taken up by the cells under these conditions. Our data suggest that raising the pH of the pulsing solution would significantly contribute to the increased efficacy of auxins in improving the vase life of cut flowers. Frontiers Media S.A. 2020-06-24 /pmc/articles/PMC7327294/ /pubmed/32670317 http://dx.doi.org/10.3389/fpls.2020.00825 Text en Copyright © 2020 Abebie, Philosoph-Hadas, Riov, Huberman, Goren and Meir. http://creativecommons.org/licenses/by/4.0/ This is an open-access article distributed under the terms of the Creative Commons Attribution License (CC BY). The use, distribution or reproduction in other forums is permitted, provided the original author(s) and the copyright owner(s) are credited and that the original publication in this journal is cited, in accordance with accepted academic practice. No use, distribution or reproduction is permitted which does not comply with these terms. |
spellingShingle | Plant Science Abebie, Bekele Philosoph-Hadas, Sonia Riov, Joseph Huberman, Moshe Goren, Raphael Meir, Shimon Raising the pH of the Pulsing Solution Improved the Acropetal Transport of NAA and 2,4-D and Their Efficacy in Reducing Floret Bud Abscission of Red Cestrum Cut Flowers |
title | Raising the pH of the Pulsing Solution Improved the Acropetal Transport of NAA and 2,4-D and Their Efficacy in Reducing Floret Bud Abscission of Red Cestrum Cut Flowers |
title_full | Raising the pH of the Pulsing Solution Improved the Acropetal Transport of NAA and 2,4-D and Their Efficacy in Reducing Floret Bud Abscission of Red Cestrum Cut Flowers |
title_fullStr | Raising the pH of the Pulsing Solution Improved the Acropetal Transport of NAA and 2,4-D and Their Efficacy in Reducing Floret Bud Abscission of Red Cestrum Cut Flowers |
title_full_unstemmed | Raising the pH of the Pulsing Solution Improved the Acropetal Transport of NAA and 2,4-D and Their Efficacy in Reducing Floret Bud Abscission of Red Cestrum Cut Flowers |
title_short | Raising the pH of the Pulsing Solution Improved the Acropetal Transport of NAA and 2,4-D and Their Efficacy in Reducing Floret Bud Abscission of Red Cestrum Cut Flowers |
title_sort | raising the ph of the pulsing solution improved the acropetal transport of naa and 2,4-d and their efficacy in reducing floret bud abscission of red cestrum cut flowers |
topic | Plant Science |
url | https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7327294/ https://www.ncbi.nlm.nih.gov/pubmed/32670317 http://dx.doi.org/10.3389/fpls.2020.00825 |
work_keys_str_mv | AT abebiebekele raisingthephofthepulsingsolutionimprovedtheacropetaltransportofnaaand24dandtheirefficacyinreducingfloretbudabscissionofredcestrumcutflowers AT philosophhadassonia raisingthephofthepulsingsolutionimprovedtheacropetaltransportofnaaand24dandtheirefficacyinreducingfloretbudabscissionofredcestrumcutflowers AT riovjoseph raisingthephofthepulsingsolutionimprovedtheacropetaltransportofnaaand24dandtheirefficacyinreducingfloretbudabscissionofredcestrumcutflowers AT hubermanmoshe raisingthephofthepulsingsolutionimprovedtheacropetaltransportofnaaand24dandtheirefficacyinreducingfloretbudabscissionofredcestrumcutflowers AT gorenraphael raisingthephofthepulsingsolutionimprovedtheacropetaltransportofnaaand24dandtheirefficacyinreducingfloretbudabscissionofredcestrumcutflowers AT meirshimon raisingthephofthepulsingsolutionimprovedtheacropetaltransportofnaaand24dandtheirefficacyinreducingfloretbudabscissionofredcestrumcutflowers |