Tea Plant Cutting Propagation Methods and Technical Key Points

One of the asexual propagation methods for tea plants. A portion of the vegetative organs of a tea plant is inserted into a moist, loose red-yellow soil nursery to form a new, complete plant. Tea seedlings propagated by cuttings exhibit heredity similar to the mother plant and, under the same environmental conditions, can maintain the traits and characteristics of the mother plant.

Types of cuttings: these can be summarized as: stem cuttings, leaf cuttings and root cuttings.

① Stem cutting methods include long-shoot, medium-shoot, short-shoot, hoop-strip and old-stem cuttings, etc. Using a complete tea branch as a cutting for propagation is called long-shoot cutting, while using an incomplete branch with four or five leaves as a cutting is called medium-shoot cutting, and cuttings with fewer than three leaves are called short-shoot cuttings. Short-shoot cuttings. They save material and have the highest propagation coefficient, and are the propagation method commonly used by the world's major tea-producing countries. China mostly uses one-leaf cuttings.

② Leaf cutting method: Select a complete, fully formed leaf, cut or snap it off from the branch so that the leaf carries some xylem and a bud, and quickly insert the lower 1/4 to 1/3 of the leaf into the nursery for cultivation. The leaf cutting method is difficult to master and has a low survival rate.

③ Root cutting methods include seed-root and root-cutting methods, etc. Seed-root: generally in early March, the main and lateral roots cut off during seedling transplanting, or thicker tea roots that have been dug up, are cut into small sections about 5 cm long, with 4 or 5 sections planted per hole, and covered with soil 3-5 cm thick. Root cutting: roots with a diameter of more than 0.7 cm are cut into small sections 7-10 cm long and inserted directly into the seedbed or arranged in sequence in pre-dug furrows (in spring and autumn a section is left slightly exposed above the ground, while in summer and winter they are inserted entirely into the soil). It is best done on cloudy days.

Cutting preparation: The process of cutting cuttings from the cutting wood is called cutting preparation. When preparing cuttings, cutting usually starts from the lower end of the branch and proceeds upward in sequence. An ordinary one-leaf short cutting is cut with one axillary bud, one complete healthy leaf and a short section of stem, 3-4 cm long; generally one short cutting is cut per internode, and for short internodes one cutting can be cut, with the lower leaves and axillary buds removed. The cut should be in the same direction as the leaf, preferably slanted, with the upper and lower cuts parallel. The lower cut of the cutting is slanted to increase the contact surface and make it easier to press tightly against the soil. If the cutting wood has axillary buds that have already grown into small branches, when preparing the cutting, leave one leaf on the main branch and one true leaf at the base of the small branch. The cut must be smooth. Remove flower buds when preparing cuttings. It is best to cut and insert immediately in the early morning and evening, or to cut cuttings during the day and insert them in the evening.

Cutting method: On the day of cutting, on the already leveled seedbed, according to the leaf length of the tea plant variety, use a row marker or a 7-10 cm wide wooden board to roll out marks for the cutting row spacing; then water thoroughly to wet the surface subsoil layer, and wait until the soil is slightly dry and no longer sticks to the hand, then begin cutting. When cutting, hold the axillary bud and leaf stalk at the upper end of the cutting between the thumb and index finger, and along the row-spacing marks insert the cutting obliquely (for slanted cuts) or straight (for parallel cuts) into the seedbed soil. About 2/3 of the short stem of the cutting is inserted into the soil, exposing the leaf stalk and tea bud, to prevent the leaf from sticking to the soil and blocking the stomata, which would cause the leaf to rot and fall off. While inserting, use the index or middle finger to press the soil near the cutting slightly firm, so that the cutting fits tightly against the soil, which helps absorb water and fixes the cutting in the seedbed. The leaf direction should face the prevailing wind of the season, arranged with the wind, so that the cutting will not sway with the wind. The plant spacing should be moderate enough that the leaves do not overlap and shade each other; after cutting, water thoroughly immediately.

Using nutrient pots for cutting propagation makes it easy to cultivate strong seedlings, improve the survival rate after transplanting, facilitate labor arrangements and establish a plantation quickly. The method uses straw or plastic and other materials to make grass-mud nutrient pots or plastic nutrient pots. Before cutting, fill the middle and lower layers of the pot with prepared nutrient soil and press it slightly firm, then fill in 3-4 cm of red-yellow soil subsoil level with the pot rim, and then insert the cutting into the pot. Nutrient pots for cutting propagation are best placed near a water source. After the cuttings are inserted into the pots, immediately set up a shade shed over the pots, cover them with shading material, or place the pots under tree shade to prevent sunburn that would cause scorching and leaf loss.

Before cutting, soak cuttings that have not been treated with mother-plant plant hormones in a solution prepared by mixing equal volumes of 50 ppm indolebutyric acid and 50 ppm naphthaleneacetic acid, immersing the base for 24 hours, then remove and insert them, which can promote root formation of the cuttings and increase the survival rate.

Cutting period: Most tea regions in China carry out summer cuttings in June-July. Summer temperatures are relatively high, callus tissue of the cuttings forms quickly, and the survival rate generally reaches more than 80%. Autumn cuttings are mostly carried out in September-October, with a relatively high survival rate. In tea regions with warm winter climates, winter cuttings can be carried out from November to January of the following year. For cuttings in spring, autumn and winter, they can be done all day long; during the high-temperature, intense-sun summer, cutting should be done before 10 a.m. and after 3 p.m.