Efficient Propagation techniques of Litchi Seedling

Grafting propagation of seedlings

1. Nursery site selection

The standard rectangle of the field is selected, the sun is sufficient, the terrain is open, the water source is sufficient, the drainage and irrigation is convenient, the water conservancy ditch and field road are perfect, which is suitable for the operation needs of nursery construction.

2. Nursery land fattening

The cohesiveness of the soil in the seedling bed should be suitable for the growth of rootstocks and the needs of seedling consolidation, and it is not suitable for the operation of raising seedlings with mud in the soil with relatively fertile and weak stickiness, so it is necessary to match the seedling bed with different soil quality. the seedling bed is the paddy field to control the water turning, ploughing and ripening, which is beneficial to improve the soil temperature and soil oxygen content, kill soil bacteria and insect eggs, and loosen the soil. On the basis of controlling the turning and drying of the field, pulling and transporting red clay from other places to enhance adhesion is beneficial to raising seedlings with mud in the future, which is the key measure to ensure the survival of planting; if the soil quality of the seedling bed is thin and weak, it is recommended to increase the application of mature sheep manure 500~600kg, calcium 50~100kg, compound fertilizer 50~100kg, lime 50kg and soil evenly according to the degree of fertility.

3. Soil moisture in the seedling bed.

After 2 months of soil fertilization and ripening in the nursery, the soil moisture of the seedling bed was adjusted as follows:

① moisture surface finishing. Soil moisture regulation requirements: soil moisture width 2m, length according to field topography and soil moisture shape, ditch width 30cm, deep 30cm, drainage ditch deep 50cm. After sowing, the soil is flattened and waiting for sowing.

② sets up the fence. In order to prevent livestock such as pigs and cattle from jumping into the nursery, fences should be set up around the nursery base. The specific methods are as follows: the cement bricks around the nursery are tightly tied with iron wire, or made of bamboo poles.

③ builds a shade shed. Standard: the span of the greenhouse is 6m, the length is 1520m, the shoulder height is 1m 1.5m, the ridge height is 1.8m 2m, and the section diameter of the bottom of the greenhouse is 6m. Program: set up a column every 2m according to the width (span) of the shed, the column is thick 6~8cm, the top forms an arch, the underground depth 50cm, cushion brick or tie cross wood, tamp, fix the bamboo pole at the top of the column into an arch, the two ends are buried in the ground and tamped; the arch spacing is 1m, and it is connected by a longitudinal tie rod to form a whole. The arch frame is covered with a sunshade net, and the end of the tightened net is buried in the surrounding soil, and the sunshade net is pressed between the arch frames with pressing wire or No. 8 aluminum wire, bamboo pole, etc.

4. Rootstock cultivation

According to experience, the old variety of litchi has a good affinity to Shuidong, Xiaohei Sanyuehong, Feizixiao and other varieties, and the old local variety of litchi is selected as the grafting rootstock. The specific work is as follows:

① seed collection and germination. After the fruit matured from April to May, the seeds of the old varieties of litchi were collected, and about 130000 seeds were needed to raise 100000 seedlings. Litchi seeds can not be placed for a long time, should be collected in batches to accelerate germination and sowing. Sprouting method: choose a piece of flat land, pile 3~5cm wet sand on it, put the washed seeds flat on the sand surface, do not let the seeds overlap, and then cover the seeds with straw 5cm thick, often sprinkle with water to keep the straw moist. After 4 days, the radicle of the seed can be exposed and sown.

Sowing and raising seedlings with ②. Sowing specification: 18cm × 12cm is suitable for plant spacing. Sowing method: carry out single-nucleus sowing, first sow the ditch according to the row spacing, the ditch depth is about 3cm, put the seeds flat in the ditch according to the original plant spacing, and cover the soil after dripping water. The suitable thickness of covering soil is 2cm. If the seed is too shallow, it is easy to dry out, and it is difficult for the seedlings to be unearthed if it is too deep.

5. Rootstock grafting

① scion selection. The grafted varieties are Shuidong, Xiaohei Sanyuehong and Feizixiao, which are matched properly with other varieties. The management of branch pruning should be done well in the early stage of harvest, and the fruit mother tree with 3-5 years old and vigorous growth should be selected as the source of ear harvesting, and the 1-2-year-old branches with full growth, full bud eyes and mature leaves in the middle and upper part of the crown should be selected. Storage requirements: conditions should be cut along with marriage, do not really need to be placed for a short period of time with fresh litchi leaves to wrap the ear strips, and then wrap a layer of wet towels, and sealed with plastic bags, put in a cool place.

② grafting time. According to experience, litchi grafting should be carried out from March to April of each year, and supplementary grafting should be carried out from September to October of that year.

③ grafting method. The grafting of seedlings in the nursery adopts the method of branch grafting. The grafting method is as follows: first, cut the rootstock. Cut the top of the rootstock at 30cm off the ground, select the straight side to cut 1 knife upward to form a 45 °slope, and cut 1 knife vertically down along the cambium or slightly xylem below the slope, with a cut length of 3 cm to 4 cm. Secondly, cut the scion. The scion branch is straight down, the lower end of the branch is cut into a 45 °angle bevel, reverse the branch, so that straight upward, the lower knife deep to the cambium or slightly xylem flat cut 1 knife, cut a smooth long section slightly longer than the rootstock cut, leaving 2'4 buds. Finally, it is jointed and sealed. The length of the cut scion is cut inward into the incision of the rootstock, so that the cambium between the rootstock and the ear is aligned with each other, bound and sealed with film belt.

6. Nursery stock out of nursery

① seedling standard. First, the rootstock has good compatibility, the graft interface develops evenly up and down, and there are no adverse phenomena such as swollen base or late unbinding caused by hanging trunk and leaf yellowing. Second, the grafting site in 30~35cm, can not be too high, the trunk is thick and straight, seedling height 50~60cm, with 3-4 branches, robust growth, leaves neat, leaf color thick green. Third, the branches are stout and the roots are well developed.

② seedlings came out of the nursery. Seedling raising method: first make a cylindrical seedling riser, take the trunk of the seedling as the center, insert the seedling device into the soil from both sides of the seedling, beat the seedling device with a sledgehammer until it is all inserted into the soil, then hold the handle of the seedling implement tightly, pull up the seedling device together with the mud seedling, cut off the overlong main root, and open the seedling device to become litchi seedlings with cylindrical mud lumps. Then wrap the whole mud mass with film, tie the film tightly with fiber belt, and supply it out of the nursery.

③ transport supply. When the first grafted seedling is slightly aged and mature, it can be planted in the nursery, it should be neatly placed in the process of shipment, it can be divided into two layers, and the seedlings should be transplanted and planted in no more than three days, and the perennial time to come out of the nursery is from June to October.

7. Nursery land management and protection