Seed Seedling technique of Taxus mairei in South China

Taxus chinensis var. mairei is a combination of medicinal, timber and ornamental, and has high value of development and utilization. Because of its poor seed coat permeability and long dormant period, it is difficult for seed reproduction. However, as long as we master the biological characteristics of Taxus chinensis var. mairei and operate strictly according to the technical regulations, seedling breeding will be successful, and the specific operations are as follows:

1. The selection of nursery and fertilizer nursery should be the paddy field with deep soil layer, loose structure, rich organic matter, good drainage and no exposure to the west (it must be the paddy soil harvested in the same year). After the middle and late rice is harvested, the soil is turned deep once after drying, the soil is broken once, and then the bed is made separately. Wide bed 1.5 meters (net bed width 1.2 meters, trail width 0.3 meters); bed height 20 cm, nursery bed length depends on the nursery. While preparing the soil and making beds, about 8000 jin of rotten pig and cow manure and 200 jin of instant high-quality compound fertilizer were applied per mu, and 6 to 8 jin of carbofuran was mixed to control underground pests. After turning the fertilizer into the soil layer and leveling the box surface, fill the box surface with yellow soil, 5 cm thick.

Second, sowing seeds at the right time after a year of storage, there are some cracks. At this time, sift out and wash the seeds, soak the seeds with 0.05% potassium permanganate solution for 10 minutes, rinse them with clean water, and then sow the seeds after drying.

There are two kinds of sowing: sowing and strip sowing: sowing is to spread the seeds evenly on the seedbed filled with yellow soil, cover the seeds with yellow soil, and then cover the seedbed with moss. For strip sowing, a 15 cm wide plank is selected and the seeding ditch is pressed on the seedling bed filled with yellow soil, with a depth of 2 cm, and the distance between the sowing ditches is 15 to 20 cm. Sow the seeds evenly in the ditch, cover the seeds with yellow soil with a thickness of 1 cm, and then cover the ditch with moss.

It should be noted that: first, the sowing amount should be strictly controlled and the amount of seeds used per mu should be 15 kg, otherwise the qualified emergence rate of biennial seedlings will be seriously affected; second, after sowing, the seedling bed must be covered with moss, as long as the moss is covered with moss in the sowing ditch. After the seedlings are unearthed, do not remove the moss and keep them on the seedling bed for a long time. The advantages of protecting seedlings with moss are as follows: to protect the seedling bed from Rain Water splash and direct sunlight, to prevent seedlings from being burned by sunlight and to avoid suffocation and death due to the formation of mud sticks in stems and leaves, and often keep the soil loose and moist, reducing the use of ploughing and weeding. But the moss covered should be thin and not too thick. in case of prolonged drought, fine loess can be used to suppress the moss, or spray water to keep the seedbed moist.

III. Field management

1. Before the seedling shade seedling is unearthed, the shade shed must be set up, which is 1.7 meters high. In dog days, the seedbed should be shaded.

2. Disease and pest control seedlings were unearthed in the rainy season, because there were many Rain Water, high air humidity, and the seedlings were prone to infection with pathogens, resulting in root rot and quenching disease, resulting in all seedling failures. Therefore, the weight lies in "prevention", that is, 800 times topiramate or half-dose: Bordeaux solution (0.5 copper sulfate, 0.5 jin of lime, 100 jin of water) is sprayed on the stem, leaf back and leaf surface of the seedlings.

3. During the period of seedling growth, attention should be paid to weeding and loosening soil and improving soil aeration conditions. The principle of weeding is: get rid of small, get rid of early. Topdressing in the early stage of seedling growth, mainly nitrogen and phosphate fertilizer, was prepared with 10% dilute feces and urine plus 0.4 jin of urea, applied every half a month. The construction was stopped in mid-September, and the shade net was removed, and the scaffolding was left for reuse.

4. If the seedlings are too dense and thin due to uneven sowing, the seedlings should be transplanted from the end of May to the middle of June. The transplanting method is as follows: transplant in cloudy or rainy days, cover the moss, drench with water and transplant.

The management of four-and two-year-old seedlings should set up the shade shed and remove the trails and surrounding weeds in time before the seedlings are transplanted. Increase topdressing for thin seedlings to promote growth.

Through fine management, the annual seedling height is 12 to 25 cm, the biennial seedling height is 30 to 35 cm, the ground diameter is 0.5 cm, and the yield is 60,000 seedlings per mu.