Germination

Seed Germination

• Germination is the growth of a plant contained within a seed leading to seedling formation.
• Seeds contain an embryo and food reserves enclosed in a seed coat.
• Dormant seeds need specific stimuli to initiate growth.
• Water, oxygen, temperature, and sometimes light are essential for seed germination.
• Water is crucial for imbibition, seed coat rupture, and enzyme activation for growth.
• Temperature affects germination rates.
• Seed dormancy may involve the embryo or seed coat.
• Hormones like abscisic acid and gibberellin regulate seed dormancy.
• Repair mechanisms address DNA damage during germination.
• Germination rate and capacity are determined by genetic, morphological, and environmental factors.

Seedling Establishment

• Radicle appearance marks the end of germination.
• Establishment utilizes food reserves stored in the seed.
• Vulnerability to injury, disease, and water stress is high during establishment.
• Germination index indicates phytotoxins.
• Establishment is a critical phase in a plant’s life cycle.

Dicot and Monocot Germination

Dicot Germination

• Germination starts with the radicle.
• Shoot emerges after water absorption.
• Shoot comprises cotyledons, hypocotyl, and epicotyl.
• Epigeal germination occurs above ground.
• Hypogeal germination involves cotyledons staying underground.

Monocot Germination

• Coleorhiza and coleoptile cover radicle and cotyledon.
• Coleorhiza grows first, followed by the radicle.
• Coleoptile emerges through the ground.
• First leaves emerge from the coleoptile.

Precocious Germination and Other Germination Types

• Precocious germination skips developmental stages.
• Pollen germination is essential for gymnosperms and flowering plants.
• Spores germinate into cells and hyphae in fungi, algae, and some plants.
• Bacterial spores allow survival in adverse conditions.

Stimulated Germination, Factors, and Related Concepts

• Light, environmental cues, and phytochrome B stimulate germination.
• Balance between gibberellin and abscisic acid is crucial.
• Nitric oxide, hormones, and light affect seed dormancy and germination.
• Lily seed germination types, oldest viable seed, pot farm, and other related concepts.

Germination Data Sources