|
division and expansion in seedlings,
and promote the development of fruits. Some of the most
important functions of gibberellins are to stimulate the
germination of seeds and the renewed growth of apical buds
in the Spring after a period of dormancy.
4.
Cytokinin
Cytokinins were discovered in a
search for things that will stimulate plant cells to divide.
One source of cytokinins is coconut milk, the liquid
endosperm. This suggests that in addition to being a food
storage system, the endosperm may also influence embryonic
development by promoting cell division. Cytokinins are
produced in the roots, are transported through the xylem and
stimulate the growth of the shoot, especially the lateral
buds.
5.
Auxins39.6
Auxins are produced by the apical
buds. They inhibit the growth of lateral buds but promote
the growth of lateral roots. This helps to coordinate the
growth of the roots with the branches overhead. Together
with cytokinins, auxins control the overall shape of a
plant, the interactions between the two control the extent
of apical
dominance.Apical
dominance means that the presence of an apical bud
|