Beschreibung
Seed germination is a critical step in the plant life cycle. When quiescent dry seeds imbibe water, their oxygen uptake increases and energy metabolism becomes very active, allowing for the biosynthesis of macromolecules and solute transport required to complete germination. The metabolic source of ATP requires the operation of mitochondrial oxidative phosphorylation at the earliest stage of seed imbibition. The reactivation of mitochondrial metabolism also provides an important source of reactive oxygen species (ROS). Under normoxic conditions, approximately 2-3% of the oxygen used by mitochondria can be converted into superoxide and H2O2. Changes in ROS homeostasis result from a modification in the balance between ROS-producing and ROS-scavenging processes. Plants are provided with soluble antioxidant compounds, such as ascorbic acid, vitamin E and glutathione and a battery of protective and repair enzymes that can efficiently destroy superoxide radicals and hydrogen peroxide. These enzymes include superoxide dismutase (SOD), catalase (CAT), peroxidases (POD), thioredoxin system enzymes and ascorbate glutathione cycle enzymes.
Autorenporträt
Érica Marusa Pergo Coelho was born in Nova Esperança, Paraná, Brazil in 1980. Graduated in Biological Sciences since 2003 and Master in Biological Sciences since 2005 and PhD in Cell Biology, Molecular and Biochemistry from the State University of Maringá since 2009. She works as Professor and researcher in the Department of Agronomic Sciences.
Herstellerkennzeichnung:
OmniScriptum SRL
Str. Armeneasca 28/1, office 1
2012 Chisinau
MD
E-Mail: info@omniscriptum.com
