8
D. MadhuBala et al.
3.1.3 Root
Epiblema of root was single-layered and composed of tightly arranged parenchyma
cells. The epidermal regions of the roots perform absorption functions, unlike the
other plants where it was responsible for protection (Warrier and Saroja 2008). Root
cap was found. Younger roots were white in colour, and the matured roots were brown
or violet in colour. Cortex was found beneath the epiblema. Cortex was composed
of parenchyma cells and differentiated into outer, middle and inner cortex. Middle
cortex forms the diaphragm. Inner cortex consists of 4–5 layers, and it varied from
place to place. Cortex composed of air spaces. Each air space has trabaculae or
diaphragm, and it was linear in shape. Endodermis and pericycle were single-layered
and composed of parenchyma cells. Vascular region consisted of vascular bundles
and pith (Table 3). Vascular bundles were found arranged radially in the stellar region.
Xylem tissues include tracheids, vessels, fibres and parenchyma cells. Phloem was
composed of sieve tubes and companion cells. Phloem fibres and parenchyma cells
were also present. Xylem and phloem were arranged in an alternate manner. Each
bundle has bundle cap made up of sclerenchyma cells. Roots of samples collected
from all the five locations exhibited similar structures.
The epidermis of leaf, root and petiole consists of a single layer of rectangular cells
which is characteristically a constant feature of this species. The epidermis is covered
with a very thin cuticle, and thin cellulose walls of epidermal cells facilitate steady
absorption from surrounding water. The most characteristic anatomical feature of
this plant is the presence of gas-filled chambers and passages in roots, leaves and
petiole. Air chambers are large, usually regular (circular to hexagonal) intercellular
spaces. These chambers provide a sort of internal atmosphere for the plant. In these
spaces oxygen emitted during photosynthesis is stored and used again in respiration.
No Casparian strips found on endodermis, this finding is confirmed by earlier works
of Barnabas (1996).
3.2 Histochemical Studies
Histochemical localization in different sections of E. crassipes were analyzed, and
the occurrence of orgastic content or secondary metabolites such as starch, protein,
tannin, fat and alkaloids in stem, petiole and leaf were observed (Table 4). Starch was
present in the hypodermis and around the vascular bundles in petiole, leaf and root of
the water hyacinth. Protein was present in the ground tissue of root, petiole and leaf
of water hyacinth. Alkaloids were found in petiole, leaf and root of water hyacinth.
Lignin was found in roots and petiole of water hyacinth. It was rarely present in
leaves.
D. MadhuBala et al.
3.1.3 Root
Epiblema of root was single-layered and composed of tightly arranged parenchyma
cells. The epidermal regions of the roots perform absorption functions, unlike the
other plants where it was responsible for protection (Warrier and Saroja 2008). Root
cap was found. Younger roots were white in colour, and the matured roots were brown
or violet in colour. Cortex was found beneath the epiblema. Cortex was composed
of parenchyma cells and differentiated into outer, middle and inner cortex. Middle
cortex forms the diaphragm. Inner cortex consists of 4–5 layers, and it varied from
place to place. Cortex composed of air spaces. Each air space has trabaculae or
diaphragm, and it was linear in shape. Endodermis and pericycle were single-layered
and composed of parenchyma cells. Vascular region consisted of vascular bundles
and pith (Table 3). Vascular bundles were found arranged radially in the stellar region.
Xylem tissues include tracheids, vessels, fibres and parenchyma cells. Phloem was
composed of sieve tubes and companion cells. Phloem fibres and parenchyma cells
were also present. Xylem and phloem were arranged in an alternate manner. Each
bundle has bundle cap made up of sclerenchyma cells. Roots of samples collected
from all the five locations exhibited similar structures.
The epidermis of leaf, root and petiole consists of a single layer of rectangular cells
which is characteristically a constant feature of this species. The epidermis is covered
with a very thin cuticle, and thin cellulose walls of epidermal cells facilitate steady
absorption from surrounding water. The most characteristic anatomical feature of
this plant is the presence of gas-filled chambers and passages in roots, leaves and
petiole. Air chambers are large, usually regular (circular to hexagonal) intercellular
spaces. These chambers provide a sort of internal atmosphere for the plant. In these
spaces oxygen emitted during photosynthesis is stored and used again in respiration.
No Casparian strips found on endodermis, this finding is confirmed by earlier works
of Barnabas (1996).
3.2 Histochemical Studies
Histochemical localization in different sections of E. crassipes were analyzed, and
the occurrence of orgastic content or secondary metabolites such as starch, protein,
tannin, fat and alkaloids in stem, petiole and leaf were observed (Table 4). Starch was
present in the hypodermis and around the vascular bundles in petiole, leaf and root of
the water hyacinth. Protein was present in the ground tissue of root, petiole and leaf
of water hyacinth. Alkaloids were found in petiole, leaf and root of water hyacinth.
Lignin was found in roots and petiole of water hyacinth. It was rarely present in
leaves.