Chemistry Reference
In-Depth Information
Figure 3.
Fossilized wallop, Czech Karst
4. Seed development and influence of the seed on the plant growth
The understanding of the relationship between seed development, environmental
conditions and seed quality at the molecular, cellular, physiological and agronomical level
are basic aim of seed science. On the beginning of seed formation is fusion of male and
female gametes and double fertilization. After fertilization relatively short and quick seed
development starts, i.e. seed become the primary recipient-sink for assimilates. This process
means parallel growth and development of the seed, which includes initial cell formation,
development of endoplasmic reticulum and growth of cell organelles - plastids, ribosome's,
mitochondria and Golgi complex. After approximately three or four weeks of the seed
development, starch and protein granules are main components of endosperm composition.
Simultaneously with chemical changes, morphological, anatomical development and quick
changes of seed weight occur. Every of these processes can be under influence of abiotic
stresses and can be modified in a different way [85]
.
Development of the most seeds can be divided into three next phases [58]. The first phase is
characterized by quick cells division and histodifferentiation to specific part of embryo
(cotyledons, growing axis), together with storage tissues (usually endosperm). Next phase is
growing phase (expansion) connected with reserves storage (carbohydrates, proteins, lipids)
in storage tissues, mostly in cotyledons and endosperm. Whole process of seed development
ends by decrease of water content (maturation phase), when seed metabolic activity is
reduced and seed is passed to quiescence state (metabolic non-active).
