Fröförlopp

Fröförlopp, a Swedish term, translates to "seed development" or "seed progression." It refers to the entire life cycle of a seed, from its formation within the parent plant to its germination and subsequent growth into a new plant. This process encompasses several critical stages.

The initial stage is seed development, which occurs after fertilization within the flower. During this phase, the zygote develops into an embryo, and the surrounding tissues differentiate to form the seed coat, endosperm (nutritive tissue), and cotyledons (embryonic leaves). The seed matures, accumulating reserves and developing mechanisms for dormancy and dispersal.

Seed dormancy is a crucial aspect of fröförlopp. It allows the seed to survive unfavorable environmental conditions and ensures germination occurs at an opportune time. Dormancy can be broken by various environmental cues, such as changes in temperature, moisture, light, or scarification (physical abrasion of the seed coat).

Germination is the process by which the dormant embryo resumes growth. It begins with water imbibition, followed by metabolic activation and cell division. The radicle (embryonic root) emerges first, anchoring the seedling and absorbing water and nutrients. Subsequently, the plumule (embryonic shoot) develops, giving rise to the stem and leaves.

Finally, seedling establishment marks the transition from seed to a self-sufficient plant. This involves the development of a functional root system and photosynthetic leaves, enabling the young plant to sustain its growth and eventually contribute to the next generation's fröförlopp. The successful completion of this cycle is fundamental to plant reproduction and the continuation of plant species.