Key points of seedling raising technology of cherry

1 Select the nursery site

The nursery land for cultivating cherry seedlings should be on a gentle slope with flat terrain and a slope of less than 5 °(the gentle slope is easy to drain and does not accumulate waterlogging), and the slope can be south, southeast and southwest. Sandy soil should be selected for raising seedlings in flat land, the groundwater level should be below 1.5m, and the soil layer is deep, loose and fertile, and the drainage is good. Cherry is susceptible to standing blight at seedling stage, and the disease is serious in hardened and wet soil. Do not raise seedlings in the previous fields for cherry seedlings or cherry orchards.

(2) soil preparation and fertilization

Before soil preparation in the nursery, 3000~4000kg high quality soil and miscellaneous fertilizer should be applied to each 667m2, and deep ploughing and raking should be made into a bed with a width of 1.0 ~ 1.2m and a length of less than 50m. In the areas prone to waterlogging in summer, high border seedlings can be used (border height 20cm, wide 80cm, leaving 30cm wide drainage ditch).

(3) adopt suitable methods of raising seedlings.

3.1 ramet breeding method. Split-plant propagation is a common method for raising cherry seedlings, which can produce large seedlings in the same year. Three methods of soil pressing, horizontal pressing and direct ramet are often used in production.

3.1.1 pile soil pressing method. In late autumn or spring, mounds with high 30~50cm are piled at the base of the selected mother tree, which promotes the sprouting tillers at the base of the trunk to take root and form new plants. In the autumn of the following year or the spring of the third year, the rooting plants were cut off and planted directly in the garden or used as rootstocks. Generally, 5-10 new seedlings can be obtained from each mother tree every year.

3.1.2 horizontal pressing method. Select the sprouting strips close to the ground and with more lateral branches, press them horizontally in the ditch, fix them with wooden hooks, then fill them with compaction, cut the rooting strips in autumn or spring of the following year, and separate new plants.

3.2 Cuttage propagation. Cherry cuttings are easy to take root, and hardwood cuttings and green wood cuttings can be used. Hardwood cuttings are widely used in production. Hardwood cutting should be carried out during the flow of sap in spring, and green wood cutting should be carried out from June to late July. The cuttings of Greenwood cuttings should be semi-lignified shoots of the year, diameter 0.3cm, too thick not easy to root, too fine nutrition. After harvest, it was cut into branches about the length of 15cm, leaving only the top 2-3 leaves, and the rest leaves were removed and inserted as soon as they were picked. The cuttings can be covered with soil or film when cutting in spring. When covering the film, the upper end of the cutter can be wax sealed with 2cm. In order to improve the seedling emergence rate, the lower end of cuttings (about 5cm) could be soaked in 100mg rooting powder or 50~100mg indole butyric acid solution for 4 hours for 5 hours before cutting. after taking out, the cuttings could be cut immediately and rooting 20 days after cutting. When new shoots 20cm, water and top dressing should be applied to promote the growth of seedlings. Before the rainy season, soil 5cm should be cultivated at the base of the seedlings. In autumn, the seedling height can reach 80cm, and the thickness can reach 0.8cm, which can reach the standard of grafting and coming out of the nursery.

3.3 grafting breeding method. The branches of sweet cherries are generally not easy to have adventitious roots, and grafting reproduction is often used in production.

4 brief introduction of grafting propagation

4.1 selection of rootstock varieties. At present, the commonly used rootstocks are agate cherry, hairy cherry, dwarf cherry, grass cherry, mountain cherry and so on. Because there is no virus disease in mountain cherry seedlings, sweet cherry rootstocks are mostly used in production.

4.2 seed collection and seed treatment. The growth period of cherry fruit is short, the development of seed embryo is not full, and it is easy to lose vitality after drying, so cherry seed treatment is different from other fruit trees. The seeds for raising seedlings can not be harvested until the fruit is fully ripe. Remove the pulp immediately after harvest, remove the seed, rinse it with clean water, dry it in a cool place, and then store it in sand immediately. When storing sand, mix the seeds with wet sand in the proportion of 1 ∶ 5. The humidity of sand should be held into a ball with your hand, and it is appropriate to spread out your hand. The sand storage site should choose to dig a storage ditch in the back shade and high dry place, deep 50cm, wide 80~100cm, first spread a layer of 10cm thick wet sand at the bottom of the ditch, and then put the mixed wet sand seeds into the ditch, generally about 40cm thickness, covered with 10cm wet sand, and then covered with fine soil or covered with grass to moisturize, the top layer covers tiles to prevent Rain Water.

4.3 sowing and management methods. It is the same as the conventional cultivation method of plum and apricot rootstock seedlings.

4.4 grafting method

4.4.1 Graft method. It is better to use split grafting, cutting grafting, ventral grafting and tongue grafting before spring germination.

4.4.2 budding method. T-shaped bud grafting and xylem bud grafting can be used in cherry growing season, and the effect of wood bud grafting is better.

The specific operation of the method of bud grafting with wood is as follows: at about 1.5cm above the bud, the scion is cut obliquely at an angle of 45 degrees to a coarseness of 2 to 5. Then cut the knife from the left and right side of the 1.5cm under the bud, cut longitudinally along the xylem until it is connected with the first incision, slightly woody, and take off the bud. Then, at the 3~5cm of the rootstock from the ground, the smooth surface is selected and cut according to the method of budding, so that the cut is slightly larger than the budding surface. Then stick the buds to the section of the rootstock, aim at the cambium, and tightly bind them with plastic strips. Note that buds and petioles are exposed.

4.5 grafted seedling management

4.5.1 do not water within 20 days before and after grafting. Cherry grafted with rain or watering can easily cause glue flow and affect survival.

4.5.2 after budding and before July, ammonium sulfate or urea was applied for 2 times, applying 105~150kg per hectare and paying attention to irrigation. During the period of seedling growth, weeding and pest control should be carried out in time.

4.5.3 untie. After the summer bud grafting survived, it should be untied in time to prevent the binding objects from strangling into the cortex to cause glue flow, and loosening should be carried out when the budding 10cm is long.

4.5.4 cutting anvil. Budding seedlings can only be cut when they sprout in spring. If the rootstock is cut too early, the anvil pile is easy to be drained down to make the buds die. The cutting stock should be carried out at the 1cm above the budding.

4.5.5 binding. When the buds grow to 20~30cm, the struts should be set up in time, and then tied up for 2 or 3 times.

4.5.6 pick the heart. When the seedling height 30~40cm, 20~30cm can be left to pick the heart, the flower bud can be formed in the next year, and it can blossom and bear fruit in the third year.

4.5.7 the seedlings grafted with branches should be removed and cultivated in time. Use plastic bags to wet sawdust to moisturize, when the bud length 5cm, should open the air.

4.5.8 in the areas where spring drought occurs, in order to promote the healthy growth of cherry seedlings in the early stage, timely irrigation, topdressing, weeding and weeding should be carried out according to rainfall to promote the maturity of cherry seedlings.