Saturday, July 12, 2008

Seed Germination

The germination of seed is dependent on both internal and external conditions. The most important external factors include: temperature, water, oxygen and light.

The germination process begins when waters is absorbed (imbibed) by the seed. This activates an enzyme, respiration increases and plant cells are duplicated. Soon the embryo becomes too large, the seed coat bursts open and the growing plant emerges. The tip of the root (radicle) is the thing to emerge and it's first for good reason. It will anchor the seed in place, and allow the embryo to absorb water and nutrients from the surrounding soil. The coleoptile is a translucent (non-photosynthesizing) protective tissue through which the first leaf emerges.