Zijuan: An Introduction to the Characteristics of a Rare Tea Tree Variety

Researchers from the Yunnan Provincial Tea Research Institute discovered a tea tree with purple buds, leaves, and stems in a tea garden of over 200 mu planted with more than 600,000 Yunnan large-leaf tea trees. The baked green tea processed from its fresh leaves has a purple dry tea color and a purple liquor color, with a pure aroma and a strong, intense taste. Because this tea tree has purple buds, purple leaves, and purple stems, and both the dry tea and the tea liquor of the baked green tea made from it are purple, it was specially named "Zijuan."

1. Botanical characteristics

The Zijuan tea tree belongs to the small tree type, large-leaf category, medium-bud variety. The tree posture is semi-spreading, the branching position is relatively high, and the branching density is medium. The leaves grow in an upward-slanting manner, with a leaf length of 11.0-13.0 cm and a leaf width of 3.4-3.6 cm, willow-leaf shaped, with a pointed tip, purple leaf color, and purple-red petioles. The leaves are relatively hard, with an average of 9-11 pairs of veins, a smooth leaf surface, and a flat leaf margin with shallow, blunt, and sparse serrations. The flower corolla diameter is 4.10 cm x 3.44 cm, with 5-6 petals, white with a green tinge, and a soft texture; there are 5 sepals, with a diameter of 0.45 cm, and the pedicel length is 0.89 cm. The sepals and pedicels are light purple in color; the petals, sepals, and pedicels all lack downy hairs; the style is 1.25 cm long, 3-lobed, with the split position mostly at 1/3; the ovary has abundant downy hairs, the pistil and stamens are of equal height, and there are about 240 stamens, connate at the base. Early October is the full blooming period, and the seed-setting rate is low. The tea fruit is spherical or elongated oval, with a slightly purple pericarp color and an average thickness of 0.71 mm. The fruit has 2-3 locules, with a fruit diameter of 1.96 cm x 1.77 cm, and the seeds are oval or hemispherical.

2. Biological characteristics of new shoots

The spring bud germination period of the Zijuan tea tree is in late February, and late March to early April is the full period for three leaves with one bud. The bud-developing ability is strong, the germination density is medium, the buds and leaves are purple, relatively plump, with abundant downy hairs and strong tenderness retention. The weight of 100 buds of three leaves with one bud is 115 g. The cutting propagation ability is strong, the survival rate is high, and the resistance to cold, drought, and pests and diseases is strong. It is suitable for planting in large-leaf variety areas, and the cultivation method is the same as that for Yunnan large-leaf varieties. This tea tree variety has medium yield. According to experiments by the Yunnan Provincial Tea Research Institute, the average yield of dry tea from 6- to 10-year-old tea trees in its experimental plot was 103.3 kg per mu.

3. Tea-making quality analysis

According to analysis by the Biochemistry Laboratory of the Yunnan Provincial Tea Research Institute, in the steamed green tea sample made from the spring tea one bud with two leaves of the Zijuan tea tree variety, the tea polyphenol content is 35.52%, amino acids 3.49%, and water extract 44.58%; in the summer broken black tea, the theaflavin content is 0.91%, thearubigin 6.99%, and theabrownin 5.86%. The sensory evaluation score for strength and intensity is 34.7 points, and the score for freshness and briskness is 37.6 points.

4. Blood pressure-lowering efficacy

In 1991, senior engineer Lin Yongyue and others from the Yunnan Institute of Materia Medica conducted multiple blood pressure-lowering experiments using domestic cats weighing 2.5-3.5 kg. The results showed that Zijuan green tea lowered blood pressure by 35.53%, which is superior to Yunnan large-leaf green tea (29.04%).

At present, on the basis of having developed Zijuan blood pressure-lowering health tea, the Yunnan Provincial Tea Research Institute is increasing the propagation of the Zijuan tea tree variety and hopes to develop and utilize it in areas such as weight loss and blood sugar reduction.