Review on physiological aspects of seed deterioration

Seed ageing is influenced by two environmental factors, RH and temperature. The deterioration of the stored seed is a natural phenomenon and the seeds tend to lose viability even under ideal storage conditions . Autooxidation of lipids and increase in the content of free fatty acids during storage period are the main reasons for rapid deterioration of seed of oil plants. Accelerated ageing has been recognized as a good predictor of the storability of seed lots. Aged seeds show decreased vigour and produce weak seedlings that are unable to survive once reintroduced into a habitat. The characteristics of the chemical composition of oil crops (soybean and sunflower) are related to specific processes occurring in seed during storage. Lipid auto-oxidation and increase of free fatty acid content during storage are the most often mentioned reasons for accelerated damage of seed of oily plant species. Vigour testing becomes more important in seeds stored under unknown or adverse storage conditions. In seed ageing damage to cellular membranes, decrease in mitochondrial dehydrogenases activities, chromosomal aberration and DNA degradation increases.