|
|
|
|||
|
Apical meristem – This top most bud on the plant is the main growing point from
which new leaves are initiated and produced. It is enclosed in the leaf of
the youngest developing leaf. Axillary meristems – These “lateral” buds are present at each node above the soil
surface. They normally remain dormant, but growth can resume from these buds
if the apical meristem is destroyed. Branch roots – These roots develop of off the main root and explore the upper
portions of the soil for water and nutrients. Cotyledons – These seed leaves are present in the embryo before
germination. They are the food source for germination processes. Unlike many
other dicots, pea cotyledons remain in the soil during emergence. Epicotyl - The part of the stem
above the cotyledons. Hypocotyl - The part of the stem below the cotyledons. In most other
legumes the hypocotyl forms an arch and elongates to pull the cotyledons
through the soil. In peas the hypocotyl does not elongate and the cotyledons
remain below the soil surface. Radicle – This embryonic root is present in the seed and grows to form
the root system. The pea radicle develops into a main taproot from which
lateral branches form. True leaves –The leaves that form above the cotyledons. The first true
leaves on a pea plant are a pair of unifoliolates (consist of only one
leaflet) opposite each other on the stem. These unifoliolates are scale-like
and have no petiole. Subsequent leaves on the pea plant have one or more
leaflets and large leaf-like stipules (appendages in the junction of the leaf
and stem). These leaves alternate up the stem, one per node. |
||||
|
|
|
|||
|
||||
