The morphological characteristics of tea plants are determined by their growing environment. In the tropical rain forest, the tea tree forms the tree or small tree big leaf shape which likes high temperature and humidity, acid and shade resistance; under the north subtropical climate condition, the tea tree is cold and drought resistant, and its morphology changes towards the direction of Bush Bush Bush small leaf; under the South and middle subtropical climate conditions, the morphological and physiological characteristics of tea tree are between the above two kinds.
A series of changes will take place in the morphological characteristics of tea tree from wild type to cultivated type, which are mainly manifested in the following aspects: tree type changes from arbor type to small tree type and shrub type, trunk changes from axis to axis, leaf from large leaf to small leaf, crown from large to small, petal from clump to single petal, fruit shell from thick to thin, seed coat from rough to smooth, etc.
Now, there are both wild and cultivated tea plants. Encounter a tea tree, to judge whether it is wild or cultivated tea, some of the differences between them can help you distinguish.
(1) Look at the overall shape of the tree: the wild type tea tree is a tree or small tree, and the growth posture of the tree is mostly upright; the cultivated tea tree is a small tree or low bush, and the growth posture is mostly open.
(2) Look at the leaves: the length of wild tea leaves is 10-25 cm, thick and crisp, with sparse blunt teeth on the edge; the length of cultivated tea leaves is 6-15 cm, thick and soft, with sharp teeth on the edge.
(3) Look at the overwintering buds and leaves: the overwintering bud scales of wild tea plants are 3-5, and those of cultivated tea plants are 2-3.
(4) Look at the corolla: the diameter of the corolla of wild type tea plant is 4-8 cm, and there are 8-15 petals; the diameter of corolla of cultivated tea plant is 2-4 cm, with 5-8 petals.
The above four points are identified by external characteristics. In the internal aspect, the difference between wild type and cultivated type is more obvious, mainly in the following aspects:
(1) Pollen: wild type tea plant pollen extreme red axis ratio is greater than 0.8, calcium content is more than 10%; cultivated tea plant pollen extreme red axis ratio is less than 0.8, calcium content is less than 5%.
(2) Biochemical components: wild type tea plants had lower contents of amino acids and tea polyphenols, but higher contents of phenylalanine; cultivated tea plants had higher contents of amino acids, tea polyphenols and phenylalanine.
(3) Terpene index: wild tea plants were more than 0.7, while cultivated tea plants were mostly below 0.7.
(4) Chromosome karyotype: wild type tea plants are mainly 2a with high symmetry; cultivated tea plants are mainly 2B with low symmetry.