Seagrass refers to the aboveground parts of seagrass plants in the family Posidoniaceae. Let's take a look at the biological characteristics and cultivation methods of seagrass with the author after harvesting in summer and autumn, removing impurities, and using it fresh or drying it in the sun!
Chemical Composition of Seagrass
Seagrass leaves contain diacylglyceryltrimethylhomoserine (DGTS).
Effective components such as trans-p-coumaric acid and caffeic acid can be obtained from the leaves.
Characteristics of Seagrass
1. Morphological Identification
Seagrass is mostly tufted. The stems are thin, twisted, and can grow over 1 meter long. They are green in color and have many branches of varying lengths.
The leaves are opposite on short branches, with two types: nutritional leaves and sporophylls. The nutritional leaves are triangular, twice pinnate; the first pinnate leaflets are opposite, ovate, 4-8 cm long and 3-6 cm wide; the second pinnate leaflets are ovate-triangular, palmately 3-lobed, with short and wide lobes, the terminal lobe is 2-3 cm long and 6-8 mm wide, with irregular shallow rounded teeth along the edge; the sporophylls are ovate-triangular, nearly equal in length and width, 10-20 cm long, with 4-5 pairs of first pinnate leaflets, opposite, elongated lanceolate, 5-10 cm long and 4-6 cm wide; the second pinnate leaflets are ovate-triangular. The lower edge of the leaflets has a tassel-like sporangial spike, which is dark brown. The plant is light, brittle, easy to break, with a faint odor and a mild taste.
2. Microscopic Identification
Stem transverse section:
Similar to the rhizome, see the rhizome of seagrass for details. The difference lies in: the thick-walled tissue consists of 5-6 rows of cells, and the walls are relatively thin; the basic thin-walled tissue is wider;
The endodermal cells have obvious Casparian strips, and there is no yellow oily substance in the cell cavity. The xylem in the vascular bundle is trichotomous.
Leaf transverse section:
The epidermal cells are in a single layer, covered with multiple cells or single cells of non-glandular hairs, and are yellowish-brown; the mesophyll tissue is incompletely differentiated into palisade tissue and spongy tissue;
The vascular bundles of the main veins are collateral, and both the upper and lower epidermis have thick-walled tissues, which are lignified or slightly lignified.
Leaf surface observation:
The periclinal walls of the epidermal cells are thin, deeply undulating, and the stomata are located on the lower epidermis, round or elongated, with a diameter of 24-31 μm. There are 2-4 subsidiary cells, either straight or indeterminate.
Non-glandular hairs consist of 1-4 cells, with longer cells at the apex, measuring 126-690 μm long and 18-32 μm in diameter, with a wall thickness of up to 5 μm, and some contain brown substances in the cell cavity.
Biological Characteristics of Seagrass
It prefers to grow in well-drained sandy soil and sandy loam. It has strong climbing ability and resistance to adversity.
Cultivation Techniques of Seagrass
It can be propagated by spores or rhizome division. Spore propagation: sow mature spores on the soil surface immediately, cover with a little soil, and keep the humidity by watering regularly.
Rhizome division: cut the rhizome into 3-6 cm long segments, plant them in the soil, cover with 4-6 cm of soil, and keep the humidity by watering regularly. The rhizome will root and grow.
