Seasonal changes in the total activity of the enzymes utilizing hydrogen peroxide in boxwood (buxus sempervírens l.) Leaves
Închide
Articolul precedent
Articolul urmator
727 4
Ultima descărcare din IBN:
2021-07-02 00:55
SM ISO690:2012
ZDIORUC, Nina, RALEA, Tudor, JELEV (HADÎRCA), Natalia, FLORENTĂ, Gheorghe. Seasonal changes in the total activity of the enzymes utilizing hydrogen peroxide in boxwood (buxus sempervírens l.) Leaves. In: Conservation of plant diversity, Ed. 3, 22-24 mai 2014, Chișinău. Chișinău: Gradina Botanica (Institut), 2014, Ediția 3, pp. 40-41. ISBN 978-9975-62-370-4.
EXPORT metadate:
Google Scholar
Crossref
CERIF

DataCite
Dublin Core
Conservation of plant diversity
Ediția 3, 2014
Simpozionul "Conservation of plant diversity"
3, Chișinău, Moldova, 22-24 mai 2014

Seasonal changes in the total activity of the enzymes utilizing hydrogen peroxide in boxwood (buxus sempervírens l.) Leaves


Pag. 40-41

Zdioruc Nina1, Ralea Tudor1, Jelev (Hadîrca) Natalia1, Florentă Gheorghe2
 
1 Institutul de Genetică, Fiziologie şi Protecţie a Plantelor al AŞM,
2 Institutul de Ecologie şi Geografie al AŞM
 
Disponibil în IBN: 17 mai 2019



Teza

Introduction Redox processes play an important role in plant resistance to adverse environmental factors. As conditions change, the activity of enzymes and some other elements of the redox system are changing. Signifi cant role in the stress response to stress factors plays the processes of free radicals decomposition. Apparition of reactive oxygen species (ROS) in the cells, particularly superoxide and hydrogen peroxide, is one of the early responses to stress impact. The cells are protected from ROS with antioxidants. These include superoxide dismutase, catalase and peroxidase. There are reasons to consider catalase as one of the terminal oxidizes of plant cells responsible for the decomposition of peroxides. Changes in the activity of redox enzymes may provide some indication about the reaction of the plant organism to the environmental stress and to assess the adaptation of plants to conditions of existence. The purpose of these studies was to determine the total activity of antioxidant enzymes in boxwood leaves depending on the growing season and temperature. Material and methods Boxwood leaves were dehydrated and rehydrated at 25oC. During dehydration and rehydration the water content, activity of PSII and activity of H2O2 decomposition of leaves extracts were determined. The extraction of crushed leaves was provided in 2 ml of 0.2M Tris buffer at pH 7.4 during 30 minutes, centrifuged for 15 minutes at 4000 g. The activity of H2O2 decomposing was determined in the supernatant. The reaction of H2O2 decomposition was initiated by adding 1.5 ml Tris buffer and 60 μcl of 0.05% H2O2 to 40 μcl liters of supernatant. Results and discussions Activity of the enzyme degrading H2O2 varies depends on the season and leaf’s age. The more intensive degradation of H2O2 (from 1.25 * 10-2 to 2.5 * 10-2 U/mg wet weight) was observed in the leaves of the 1-st year of vegetation and, in our opinion, is due to their active processes of growth and development. Seasonal dynamics is characterized by increased activity of enzymes in the autumn and spring (2.0 * 10-2 to 2.5 * 10-2 U / mg wet weight), periods that are responsible for the processes associated with the preparation of plants for the winter rest and output thereof in the spring. The data indicate that the change in temperature conditions signifi cantly affect the course of physiological and biochemical processes, and, above all, on the changes in the activity of antioxidant enzymes, which leaves in the winter boxwood reduced almost twice. Conclusions 1. During preparing boxwood plants for enduring winter frosts, the corresponding physiological changes in tissues of leaves assure transition to quiescence and increasing their frost resistance. 2. The transition of plants from the active growing season for the winter rest is accompanied with slowdown of antioxidative enzymes activity, while in the spring, on the contrary, their activity is increasing.