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**Group 1: Seed Germination Process**

– Germination is the growth of a plant contained within a seed, resulting in the formation of a seedling.
– Seeds contain an embryo and food reserves wrapped in a seed coat.
– Dormant seeds require specific stimuli to resume growth.
– Seed germination depends on internal and external conditions.
Water, oxygen, temperature, and light are crucial for seed germination.
– Seeds need water for imbibition, which leads to the breaking of the seed coat.
Water activates hydrolytic enzymes that break down food reserves for growth.
Oxygen is required for seed metabolism and energy until leaves grow.
– Temperature affects metabolic and growth rates in seeds.
– Seed dormancy involves changes in membranes and plant hormones.
– Radicle appearance marks the end of germination and start of establishment.

**Group 2: Factors Affecting Germination**

Water, nutrients, and light are essential for seedling growth.
Oxygen in soil pore spaces is essential for seed germination.
– Some plants like rice can undergo anaerobic germination in waterlogged conditions.
– Seeds have specific temperature ranges for germination.
– Cold stratification breaks dormancy for some seeds.
– Scarification weakens seed coat for germination triggers.
– Light is an environmental factor that stimulates the germination process.
– Seeds sense environmental cues to determine the perfect time to germinate.
– The balance between gibberellin (GA) and Abscisic acid (ABA) is crucial for seed dormancy and germination.

**Group 3: Germination Rate and Capacity**

– Germination rate indicates the likelihood of seeds to sprout over a specific period.
– It is expressed as a percentage and influenced by genetic, morphological, and environmental factors.
– Useful for determining seed quantity needed for planting.
– Seed germination rate is the reciprocal of the time taken for germination.
– Germination capacity refers to the number of seeds in a population able to complete germination.

**Group 4: Repair of DNA Damage during Germination**

– Seed quality declines with age due to genome damage accumulation.
– Repair processes are activated during germination to address DNA damage.
– DNA single- and double-strand breaks can be repaired.
– The DNA damage checkpoint kinase ATM plays a crucial role in germination and repair.
– Aging seeds accumulate DNA damages that need repair during germination.

**Group 5: Types of Germination (Dicot and Monocot)**

– Germination stages include radicle emergence, cotyledon growth, and shoot development.
– Epigeal germination occurs above ground, with the hypocotyl forming a hook.
– Hypogeal germination involves the elongation of the epicotyl.
– Monocot seeds have coleorhiza and coleoptile covering the embryo.
– Coleorhiza emerges first, followed by the radicle and coleoptile.
– Precocious germination skips some seed development stages.

Germination (Wikipedia)

Germination is the process by which an organism grows from a seed or spore. The term is applied to the sprouting of a seedling from a seed of an angiosperm or gymnosperm, the growth of a sporeling from a spore, such as the spores of fungi, ferns, bacteria, and the growth of the pollen tube from the pollen grain of a seed plant.

Sunflower seedlings, three days after germination
Sunflower time lapse with soil. cross section, showing how the root and the upper part of the plant grow
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