Tea cultivation-- selection of improved varieties and reasonable close planting

1. Selection of improved seeds (seedlings) is the basic means of production for tea cultivation, and any cultivation method is based on improved seeds in a certain period. Since 1980's, tea cultivation has been fully adopted the method of close planting dwarfing and no-tillage. Because of the reduction of individual space and the increase of population density, it is more necessary to match with the improved varieties to achieve the ideal effect. Such as Fuding white tea, Qianmei 101, Qianmei 303, etc., are suitable for dense cultivation of excellent tea species.

2. The best time for collecting and processing tea seeds is from cold dew to early winter. Early seed collection, immature embryo and insufficient material accumulation affect seedling emergence and seedling growth. Too late picking tea seeds landing, not only waste a lot, but also miss the appropriate time for sowing. The collected tea fruit should be removed from the shell in time, and the tea seed should be spread in a cool and ventilated place. The thickness of the spread should not exceed 10 cm, and the tea seed should be stirred frequently to make the tea seed breathable evenly, dry and wet consistently, and then the seed should be sown immediately. In order to accelerate seed germination, eliminate collateral pathogens and promote neat and healthy seedlings, tea seeds should be disinfected before sowing. Firstly, the seeds damaged by diseases and insect pests, mildewed, broken seed coat, shriveled seeds and empty shells are removed, then screened by a sieve to separate the big and small seeds and sow them separately. After emergence, the care of small seed seedlings is strengthened to make up for their congenital defects. Winter sown tea seeds can be sown directly without soaking and swelling. Before sowing, seeds are disinfected with 1%~2% formalin solution or 1% copper sulfate solution. After soaking for 1~2 hours, they are immediately taken out and washed with clean water. Spring sowing tea seeds due to a long time storage to reduce the water content, need to soak in water for 3 to 4 days before planting, so that part of the tea seed shell expansion, take out sowing.

3. Reasonable close planting is to select excellent varieties, adopt appropriate planting density and planting methods, use comprehensive agricultural techniques, establish a more reasonable dynamic population structure from seedling stage to adult stage, make full use of soil fertility and light energy, and obtain maximum economic benefits per unit area. Planting specifications, can be in the range of 120~150 cm row width, row 23 small rows, row cluster spacing of 30~40 cm x 23 cm, 7~10 seeds per hole, seed quantity of 40~50 kg per 667 square meters. When planting, attention should be paid to the following technical problems:

(1)Plough deeply and apply sufficient pre-seed fertilizer. The tea garden that has reached the deep ploughing requirement at the time of reclamation can be sown as long as sufficient base fertilizer is applied. If the reclamation depth is not enough, it should be cultivated before planting, and then fertilizer planting. If the base fertilizer dosage is manure, compost or decomposed green manure per 667 square meters, 2000~4000 kg and 100 kg of calcium superphosphate should be applied, and the seedling emergence is 10~15 days earlier than that of spring sowing, and the emergence rate is also higher. Where conditions are available, efforts should be made to plant seeds in November to December of the same year. Spring sowing can also be carried out in cold mountain areas due to heavy snow in winter or missed due to external seed transfer. However, the whole sowing work must be completed before the end of March.

(2)Hole seeding with shallow soil cover. In order to enhance the population superiority and stress resistance of seedlings, multi-seed hole sowing should be carried out in newly planted tea gardens. The number of seeds planted in each hole should be determined according to the quality of tea seeds. Generally, 5~10 seeds with good seed quality and 10~15 seeds with poor seed quality should be used. After seedling emergence, the seedlings should be thinned and determined. After tea seed is planted, the soil should be shallow and not deep, generally not more than 7 cm. When the seedlings are buried too deep, they are difficult to emerge, and a large amount of nutrients are consumed to grow in the soil. After they are unearthed, they are often weak and can not withstand the high temperature environment under the scorching sun, which is easy to cause burns. If the tea seeds are of poor quality or even before the seedlings are unearthed, the mother nutrients have already been exhausted, resulting in lack of seedlings. The soil is too shallow to withstand rain erosion, and tea seeds exposed to the ground cannot germinate. The soil covering the tea seeds should be soft and finely divided, not into lumps, and some protective materials can be covered on the soil surface, such as sawdust, forest rotten leaves, chaff, etc., which can not only keep the soil loose but also avoid being washed by water, which is very beneficial to the germination of tea seeds.

(3)Transplanting tea seedlings. Transplanting tea seedlings is technically strong and must be treated seriously. The main keys are as follows: ① timely transplanting. Grasp the suitable period of transplanting. Transplanting tea seedlings should be carried out when the growth of the aboveground part stops and the underground roots begin to grow, because planting seedlings at this period is beneficial to the rapid recovery and development of the limited line. The root growth activity is more vigorous in late autumn and early spring, and the time is longer, so the general seedling planting should be carried out in September to November and 2 to 3 items in spring. 2. Seedling. When seedlings are raised, try to bring more soil and less damage to roots. The root system of tea seedlings is closely intertwined with the soil. If there is no soil or less soil, it will damage the absorption roots and affect the survival and growth of tea seedlings after planting. In order to make tea seedlings out of the nursery can bring more soil, in the day before the seedling should be watered a permeable nursery, so that tea roots and soil, soil and soil easy to bond between more soil, such as nursery sandy soil should be more carefully engaged. At the same time, seedling selection should be carried out to remove diseased plants, weak plants, impure plants with mixed varieties and severely damaged seedlings. If it is inconvenient to carry soil for long-distance transportation or difficult to carry soil in sandy land, the roots should be soaked in yellow mud after seedling picking and water management should be strengthened on the way and after planting. 3. Transplant well. Planting seedlings had better be carried out on cloudy days or after rain. Before planting tea seedlings, planting ditches should be dug and base fertilizer should be applied. When planting, seedlings are first put according to the pre-calculated density and row spacing, and then planted. Planting method is to lift seedlings with one hand so that the tea roots spread evenly according to the original natural form; the other hand slowly fill in fine soil, while filling and gently pressing the tea roots and soil. Fill the ditch with soil and then step on it, then twist it into root water, wait for water to soak into the soil, and then cover the surface with a layer of loose soil. The planting depth should exceed the original root neck by 2~3 cm. After transplanting, pruning should be carried out in time. The amount of pruning depends on the degree of root damage. Root damage less can stay 20~25 cm high pruning, root damage more to stay 15~20 cm is appropriate, in order to facilitate the balance of income and expenditure above and below the ground, so that seedlings early recovery root trauma, normal development and growth as scheduled. In case of continuous sunny days, the seedlings should be shaded and irrigated before the aboveground part has not grown normally, so that the soil can be kept moist frequently to ensure the survival of tea seedlings.