Transcript Document

DEFINITIONS
• Growth or grow means an increasing incident of volume which
covers the increase of the number of cell, cell volume, kinds of cell
and substances of cell that is irreversible.
• Development is a process that is parallel to growth. Development
can be defined as a process that leads to maturation and can not be
measured.
MERISTEM TISSUES OF PLANT
Anatomy of tree
(Campbell, 1997).
1. Growing point :
It happen in root and stem ends and make plants higher and
loonger. It is called primary growth.
There are 2 theories of growing point::
a. Histogen Theory stated by Hanstein. Consist of:
- Dermatogen,
- Periblem,
- Plerom,
b. Tunika Korpus Theory stated by Schmidt. Consist of:
- Tunika,
- Korpus,
2. Vessel Cambium (between xilem dan floem). Makes plants
grow wider, it is called secondary growth.
3. Sponge Cambium (felogen) the growth goes outside to form
sponge cells (felem) instead of broken epidermis. This is to
cover surface and go inside making living feloderm of cell.
There is a cleft among sponge cells that is as a place where
the air comes in and it is called cell lenti.
4. Perisikel (perikambium) ia a tissue which functions to form
branches of root and stem.
5. Stem Parenkim
INFLUENCIAL FACTOR OF GROWTH
Table. Nutrition needed by plants
1. Nutrition fertilizer
influence plant growth
(see picture). E.g,
nutrition needed by plants
are shown in the table.
Picture 1. The differences of growth in corn. Plant
has enough nitrogen (left). Deficiency of nitrogen
elements (right) (Campbell, 2006).
Picture 2. Leaf condition (a) normal leaf, (b)
nitrogen deficiency, (c) phosphate deficiency, (d)
potasium deficiency (Campbell, 2006).
1. Gen is the carrier factors of nature that are owned by
all creatures, both plants and animals.
2. Environment around plants:
1. Temperature: plants can live well in optimum
temperature
2. Light, at green leaved plants, the light is
regnited for photosynthesis.
3. Water o r moisture is needed by plants for the
growth.
3. Growing substance (hormone) can influence the growth
of certain organs.
KINDS OF GROWING SUBSTANCES
1. Auksin is indl asetat cmpound and its
combination, found in enlonging plant
ends. Functins of auksin:
1. Stimulating cell enlonging
2. Stimulating growing plants
3. Stimulating the forming of fruits
without pollination called
partenokarpi.
4. Bending stem
5. Stimulating lateral & fibrous root
6. Stimulating the split of vessel
cambium
7. Making differential cells xylem
8. Increasing the development of
flower and fruits.
9. Apical domination (obstructing
the growth of side shoof/ arnynt)
Picture. (Campbell, 2006).
1. Giberelin, was found in giberella
fujikuroi (a kind of parasitic moss
in rice plant). Function of
giberelin:
1. Stimulating cambium
activities
2. Causing plants in bloom
faster
3. Enlarging fruits
4. Influencing embryo growth
5. Obstructing seed forming
6. Stimulating the forming of
pollen line and flowers.
7. Breaking seed dormant and
side bud.
Picture 8.25. The effects of giberelin wards fruit growth.
(Campbell, 2006).
lanjutan …
1. Sitokinin
Sitokinin function to:
 Stimulate the spilt of cell
faster
 Stimulate bud growing to
the side
 Stimulate the widening of
leaf
 Reduce apical domination
 Control the forming of
flower and fruit
 Delay the falling of leaf,
flower, and fruits by
increasing food supply to
those organs.
Picture. The effect of sitokinin toward leaf wideming.
1. Kalin functions to stimulate the growth of certain organs.
Based on organs affected, it is devided into:
1. Kaulokalin, functions to stimulate stem growth
2. Rhizokalin, functions to stimulate root growth
3. Fitokalin, functions to stimulate leaf growth
4. Anthokalin, functions to stimulate flower growth
5. Traumalin acid, functions to stimulate “kalus”
growth of dicotil stem injured.
6. Absisat acid, functions to obstruct the growth in
bad conditions so that the plant is in dormant
condition.
The Vascular Cambium
Definitions Cell division related to cambial activity
Axial: Along the axis of the organ, or organism
Radial: At right angles to the axis, i.e., along a
radius
Tangential: At right angles to a radius.
Ray Initial: Meristematic cambial cell. Forms a
file of cells (one or more wide) that is composed
of parenchyma. Orientated ALONG a RADIUS.
Contributes to the RADIAL transport system
Fusiform Initial: Meristematic cambial cell. Forms
new secondary xylem and secondary phloem and
associated cells.
Contributes to the AXIAL transport system.
Notes
THE VASCULAR CAMBIUM
The vascular cambium is unlike the primary meristems (root and shoot
apex) of the plant, in that it produces new cells and tissues which add to the
axial system (i.e. the conducting system) as well as to the radial system
(i.e. the lateral transport pathway). In contrast, apical meristems of the
shoot and root add only to the axial system. The cells of the vascular
cambium do not fit the regular concept of meristematic cells (i.e. small,
isodiametric shaped cells, with a dense cytoplasm and containing large
nuclei). Cambial cells are usually highly vacuolate and occur in two forms,
namely fusiform cells and ray cells. Fusiform cells are prism-shaped with a
distinct wedge-shape at both ends. Ray cells are short and squat.
Tangentially, both cell types may be wider than they appear in radial section
or longitudinal view. The slides that follow will assist to orientate you with
respect to the planes of cell division within the cambium.
The two cell types (fusiform and ray cells) have unique functions. Fusiform
cells usually only produce cells associated with the axial system -- that is,
they produce either new elements of the xylem, or elements of the phloem.
Fusiform cells thus add new cells to the AXIAL conducting system. Ray
cells on the other hand, produce ONLY ray cells and thus add to the
RADIAL system of the plant
AXIAL
Axial: Longitudinal
translocation, xylem
& phloem elements.
Radial: Lateral
translocation.
Carbohydrate from phloem,
to parenchymatic (living)
tissue, water from xylem to
living tissues as well.
Fusiform vs. ray initials
radius
tangent
Fusiform and ray cells form
FILES of cells – each file
contains a number of
differentiating elements. Both
can divide radially OR
tangentially
endarch
TANGENTIAL face
exarch
TANGENTIAL face
exarch
TANGENTIAL face
RADIAL face
RADIAL face
Development of secondary vascular tissues in stems
During primary growth, the
vascular bundles produce
PRIMARY vascular tissue.
These are the primary
phloem (proto + meta) and
primary xylem (proto and
meta).
The fascicular cambium
separates the two
tissues.
Remember: a fascicle is a vascular bundle
1.
Development commences within the fascicular cambium
(between the primary phloem and primary xylem)
First activity is in the vascular bundle
2.
FCZ = fascicular cambial zone
Secondary xylem
Secondary phloem
FC
Secondary xylem and phloem are
produced by the fascicular
cambium (FC).
3
The interfascicular regions begins to differentiate
and a cambium originates here.
The interfascicular
cambial area in
herbaceous stems is not
usually active, thus does
not produce new
phloem or xylem tissues
PX
MX
2X
2P
1P
PPF
CZ
3b
3a
A widening band of secondary
vascular tissue results from the
cambium’s activity.
CZ
4
The ring of secondary tissue is
Complete. The interfascicular and fascicular
cambia together form a vascular cambium
Cambial activity in the root
Phloem
Protoxylem
Metaxylem
endodermis
pericycle
Typical Dicot Root, end
of primary growth
(cambial activity in
Gymnospermous roots is
very similar).
Formation of the cambium. Stage 1.
endodermis
pericycle
cambium appears
between the metaxylem
and the metaphloem
Typical Dicot Root
Formation of the cambium. Stage 2.
endodermis
pericycle
Typical Dicot Root
filling out
2X
2P
Cambial cells
differentiate more
rapidly at the interface
between the metaxylem
and the metaphloem.
secondary phloem is produced
centrifugally (outwards) as is
secondary xylem. In a centripetal
(inward) direction. Outward pressure
begins to be applied to the primary
phloem strands. These strands are
gradually forced outwards, to make
way for the newly-added secondary
vascular tissues.
filling out
E = endodermis
P = pericycle
2X = secondary xylem
2P = secondary phloem
P – pericycle
E = endodermis
2X
2P
P
E
2. Primary phloem strands
become crushed, loose
functionality
1. Outward
pressure caused by
the addition of new
cells continues –
effectively ‘rounding
out’ the ring of
secondary vascular
tissue
2X
2P
P
E
3. Primary phloem strands
have lost their functionality
Remnant of primary phloem
strands – (located by orange
arrows) become completely
crushed, and are non-functional
E
2P
2X
E = endodermis
P = pericycle
2X = secondary xylem
2P = secondary phloem
P – pericycle
E = endodermis
P
The root will retain its primary
xylem, which will be visible and may
be functional