Integument (botany)
The integuments are part of the ovule of the seed plants . There are usually one (unitegmic) or two (bitegmic), rarely three layers, which enclose the nucellus . After fertilization, the integuments become the seed coat (testa). If the seed coat can be divided into two different, separable layers, the inner layer, which is formed from the inner integument, is called the tegmen ( glass skin, inner skin, core skin) and the outer layer, which is formed from the outer integument, is called the testa . In the case of bitegmic integuments, however, there is often no differentiation of the seed coat into testa and tegmen, since these have grown together or the inner integument has degenerated.
The seed coat, which consists of the integuments, can also be differentiated into an inner hard, heavily lignified sclerotesta and a fleshy, outer sarcotesta .
The integuments leave a small opening, the micropyle , free. In the case of angiosperms (Magnoliopsida) on the growing through these micropyle most scar lying pollen with the pollen tube in the double fertilization therethrough.
proof
- Gerhard Wagenitz : Dictionary of botany. Morphology, anatomy, taxonomy, evolution. With English-German and French-German registers . 2nd expanded edition. Nikol, Hamburg 2008, ISBN 978-3-937872-94-0 , pp. 159, 325 (licensed edition from 2003).
