Cultivation techniques of American apricot plum

American apricot plum is a new interspecific hybrid introduced from America by Economic Forest Research and Development Center of Chinese Academy of Forestry. This variety is bred by multi-generation hybridization of apricot and plum. Its fruit has special rich fragrance, sugar content is much higher than that of any single apricot or plum variety, and soluble solid content can reach 18~20%. It is one of the new fruit varieties with best market prospect. At present, there are 7 varieties introduced: Flavor Rose, Flavor Queen, Flavor Xin, Flavor Emperor, Dinosaur Egg, Flavor King and Flavor Thick.

I. Excellent characteristics

1. Big fruit, early bearing and high yield. American apricot plum bears fruit 2 years after planting, and enters into full fruit stage 4~5 years after planting. The average single fruit weight is 80~120g, and the maximum single fruit weight is 150g. The yield per mu in full fruiting period can reach 1800~2500kg.

2. The fruit is gorgeous in color, high in sugar content, unique in flavor and rich in nutrients. When the fruit matures, the pericarp is purple, red, reddish yellow or orange; the flesh is bright red, pink or orange, hard and sweet. Soluble solids content was 40%~70% higher than that of Jintaiyang apricot and Heibaoshi plum. It is rich in vitamins and mineral elements, especially vitamin A, vitamin C and β-carotene and potassium, among which β-carotene has a certain anti-cancer effect. Free of saturated fatty acids and cholesterol.

3. The fruit is storage-resistant. The fruit can be stored for 15~30 days at normal temperature and 3~6 months at 2~5℃.

4. Fewer pests and diseases, strong adaptability. American apricot plum can adapt to various types of soil conditions, the requirements for soil pH are not strict, and the ability to resist drought and cold is strong. It can be planted in most areas where apricot and plum are suitable.

II. Cultivation techniques

1. Planting time: from early November to late February.

2. Planting density

The planting density of apricot and plum should be determined according to the variety characteristics and site conditions. The growth potential of Weiwang is weak and the plant type is small, so it can be planted with 111~167 plants per mu at a plant spacing of 2 m ×3 m or 2 m ×2 m, and 56~83 plants per mu at a plant spacing of 3 m ×3 m, 2 m ×4 m and 3 m ×4 m for other varieties.

3. Planting methods

First, excavate 80 cm square planting holes (hole length, width and depth are 80 cm) in the planting field. When excavating, separate topsoil and subsoil. When backfilling, mix 20~30 kg decomposed organic fertilizer with topsoil, then fill the bottom of the hole to half of the depth of the hole, and then backfill the subsoil to 10 cm below the ground surface to facilitate watering after planting. When planting, first dig a small pit in the center of the planting hole, put the seedlings into the small pit, fill and compact and irrigate enough water, and seal the soil after the water completely seeps down. When planting, fill the soil and lift the seedlings at the same time, so as to fully expand the root system. The planting depth is suitable for the rhizome to be level with the ground surface. Because most apricot and plum varieties are cross-pollinated, pollinated varieties should be allocated during planting. For example: the pollination tree of flavor rose is Weidi and dinosaur egg; the suitable pollination tree of flavor queen is dinosaur egg, Weidi and Weihou; Weixin can self-pollinate, but it is better to configure a certain proportion of Weidi or flavor rose. According to the cultivation purpose, the allocation ratio of each variety to pollinated tree is 5:5~8:2.

4, dry

The drying time is from planting to budding. Dry height is generally 60 cm.

5. Main branch picking

From the end of April to the beginning of May, the tender shoots of apricot plums grow to 60~70 cm and are pinched to promote lateral branches and cultivate main branches. From late May to early June, when the lateral branches grow to 50~60 cm, select three main branches with strong growth potential and appropriate orientation to leave 40 cm for topping; flatten the branches with space to facilitate early flower bud formation; and thin out other branches that are too dense.

6, pull branches

Branches are pulled in mid-October. Auxiliary branch, temporary branch, competitive branch, pull branch angle larger, can be leveled. Extension of branches, lateral branch pull angle generally 60~80 degrees. Taste thick, flavor rose branches soft, pull branch angle should be small, to fruit crown pressure.

7. Trimming

American apricot plum tree suitable for natural open shape or two-layer open shape is good. The structure of natural open-heart tree body is as follows: trunk height is 40~ 50cm, three main branches extend at an angle of 40~45°, and 2~3 branches are evenly distributed on the main branches. The structure of two-layer scattered heart-shaped tree body is as follows: the first layer has three main branches, the layer spacing is 80 cm, the second layer has two main branches, and the above heads are happy. When pruning annual saplings in winter, they should be gently cut and slowly released, and the pruning amount should be light to avoid excessive pruning; branches should be slowly released and allowed to grow, with less or no truncation. Specific pruning method: the main branch extension branch interception 50 cm, for the main branch on the lateral branch, select the appropriate orientation angle of the lateral branch interception 30 cm, promote the formation of fruit branch group. The auxiliary branches are slowly laid and not cut. In summer pruning, branches should be thinned mainly, less truncated or truncated, dense branches, overlapping branches and budding branches should be thinned, tree structure should be improved, and ventilation and light transmission conditions should be improved.

8. Flower and Fruit Management

Apricot plums should be cut again before flowering, thinning out thin and weak flowers. When bees were released at full flowering stage, spraying 0.3%~0.5% borax and 0.3% urea solution on leaves could significantly increase fruit setting rate. Apricot plum fruit thinning should be in the first physiological fruit drop, generally every 10 cm to leave a fruit. The fruit weight can be increased by applying 100~150 g potassium sulfate compound fertilizer per plant during fruit expansion stage. Spraying 0.3%~0.5% potassium dihydrogen phosphate solution once every other week during apricot plum coloring period can obviously increase sugar content and promote coloring. After fruit harvest, fertilizer and water management should be strengthened to promote tree recovery. At the same time, paclobutrazol 500~800 times 2~3 times can be sprayed on leaves to control tree growth and promote flower bud formation.

9. Water and fertilizer management

Apricot plum is not resistant to flooding, in order to facilitate drainage, should be along the planting line with the trunk as the center line, 50 cm on both sides of the center line outside the excavation depth of 20 cm ditch, at the same time will be sealed under the tree tray, piled into a circular arc shape, to facilitate drainage irrigation. Irrigation should be done before anthesis, after anthesis, young fruit expansion and before freezing every year. Irrigation should be done in time from July to August according to soil moisture status. After fruit harvest, water and fertilizer management should be strengthened, 0.5 kg N, P, K compound fertilizer should be applied to each tree to improve the nutrient accumulation of the tree body, so as to promote the restoration of tree vigor and form full flower buds. From late October to early November, trenches or grooves with a depth of 40 cm and a width of 30 cm are dug on both sides of tree rows, and decomposed organic fertilizer 30 - 50 kg or calcium superphosphate 2 - 3 kg and urea 0.5 - 1 kg are applied to each plant.

10. Pest control

(1) Perforation disease usually begins in late March to early April. In the middle of March, 70% thiophanate-methyl powder 1000 times plus 65% mancozeb WP 500~800 times or 50% carbendazim WP 800~1000 times can be sprayed.

(2) From late March to mid April in spring, aphids often harm the tender shoots of apricot plums, causing them to stop growing. 40% Rite WP 1000~1200 times solution can be used for spraying control.

(3) Pear fruit borer generally in June to July began to harm, can be used 50% of fenitrothion emulsion 1500 times spray, eggs and adult emergence have a good killing effect.

(4) From June to July, the scarab harm is more serious. According to the pseudo-death of scarab, the method of combining artificial and light trapping can be adopted. Artificial shaking trees or catching adults can be used. If conditions permit, black light can be used to trap them.

(5) In August, red spider was more harmful, and 60% parmite could be used to control it.