Affordable Access

deepdyve-link
Publisher Website

Changes in phytohormone content and associated gene expression throughout the stages of pear (Pyrus pyrifolia Nakai) dormancy.

Authors
  • Ito, Akiko1
  • Tuan, Pham Anh1, 2
  • Saito, Takanori1, 3
  • Bai, Songling1, 4
  • Kita, Masayuki1
  • Moriguchi, Takaya1
  • 1 Institute of Fruit Tree and Tea Science, NARO, 2-1 Fujimoto, Tsukuba, Ibaraki 305-8605, Japan. , (Japan)
  • 2 Department of Plant Science, University of Manitoba, Winnipeg, Manitoba R3T 2N2, Canada. , (Canada)
  • 3 Graduate School of Horticulture, Chiba University, Matsudo, Chiba 271-8510, Japan. , (Japan)
  • 4 Zhejiang Provincial Key Laboratory of Horticultural Plant Integrative Biology, Zhejiang University, Hangzhou, Zhejiang 310058, China. , (China)
Type
Published Article
Journal
Tree Physiology
Publisher
Oxford University Press
Publication Date
Apr 08, 2021
Volume
41
Issue
4
Pages
529–543
Identifiers
DOI: 10.1093/treephys/tpz101
PMID: 31595966
Source
Medline
Keywords
Language
English
License
Unknown

Abstract

To elucidate the role of phytohormones during bud dormancy progression in the Japanese pear (Pyrus pyrifolia Nakai), we investigated changes in phytohormone levels of indole acetic acid (IAA), gibberellic acid (GA), abscisic acid (ABA) and trans-zeatin (tZ). Using ultra-performance liquid chromatography/mass spectrometry/mass spectrometry, we monitored phytohormone levels in the buds of field-grown and potted trees that were artificially heated to modify the timing of dormancy and flowering (spring flush) progression. We also analyzed the expression of GA- and ABA-metabolic genes during dormancy. Indole acetic acid and tZ levels were low during dormancy and increased toward the flowering stage. Gibberellic acid levels were maintained at relatively high concentrations during the dormancy induction stage, then decreased before slightly increasing prior to flowering. The low GA concentration in potted trees compared with field-grown trees indicated that GA functions in regulating tree vigor. Abscisic acid levels increased from the dormancy induction stage, peaked near endodormancy release and steadily decreased before increasing again before the flowering stage. The ABA peak levels did not always coincide with endodormancy release, but peak height correlated with flowering uniformity, suggesting that a decline in ABA concentration was not necessary for resumption of growth but the abundance of ABA might be associated with dormancy depth. From monitoring the expression of genes related to GA and ABA metabolism, we inferred that phytohormone metabolism changed significantly during dormancy, even though the levels of bioactive molecules were consistently low. Phytohormones regulate dormancy progression not only upon the reception of internal signals but also upon sensing ambient conditions. © The Author(s) 2019. Published by Oxford University Press. All rights reserved. For permissions, please e-mail: [email protected]

Report this publication

Statistics

Seen <100 times