THE GLUTATHIONE ACCUMULATION ON MIXED BUD TISSUES DURING THE DORMANCY OF JAPANESE PEAR

Glutathione (GSH) can exert effects in the regulation of several growth and developmental events.
Considering that glutathione can play an important function during the bud dormancy, the glutathione pool on Japanese pear (Pyrus pyryfolia) bud tissues of plants exposed to different environmental conditions through the winter season was analyzed.
Mixed buds of plants kept under natural conditions of cold accumulation (NC) presented higher GSH/GSSG ratio and a significant increase in the total glutathione content in concomitance with the endodormancy overcoming.
A correspondingly greater glutathione reductase (GR) activity, enzyme which reduces GSSG back to GSH, was also found in the bud tissues of plants under NC. Bud cushion and shoot tissues presented a less significant increase in the total glutathione content and GR activity.
Cold deprived (CD) plants did not show bud break and a considerable decline on the glutathione content, through the reduction of GR activity, was observed in buds.
From these results, it can be assumed that the chilling exposure has an important influence on the GSH accumulation and on keeping high GSH/GSSG ratio in bud tissues at breaking time.
This trait can be considered as a part of the complex dormancy overcoming process.

VIII International Symposium on Temperate Zone Fruits in the Tropics and Subtropics

G.C. Zanol, Y. Sekozawa, S. Sugaya, H. Gemma

chilling, cold deprivation, endodormancy, growth resumption, Pyrus pyrifolia

https://doi.org/10.17660/ActaHortic.2010.872.7