Cultivation and Management techniques of Plum

? I. cultivation techniques

(1) selection of seedlings

Select plum seedlings with pure variety, complete root system, strong, full bud, no quarantine object and no diseases and insect pests.

(2) colonization

Generally, the row spacing is 2.5 m × 4 m, and the plant is planted before bud germination (preferably before April 20).

Plum has self-flowering sterility phenomenon, therefore, the cultivated variety should not be single, should be planted at a certain distance with the same flowering period of different varieties as pollination trees, the proportion is 4:1 or 8:1.

? II. Fertilizer and water management

(1) fertilization

1. Base fertilizer

Base fertilizer is the basic fertilizer that can supply plum trees with a variety of nutrients for a long time, generally with late-acting farm manure, such as compost, barnyard manure, crop straw, green manure, deciduous leaves and so on. It is better to apply basic fertilizer in autumn, adult plum trees, and each plant should apply 50 kilograms of farm manure.

2. Topdressing

(1) topdressing before flowering: 0.5 kilogram of available nitrogen fertilizer or 25 kilograms of mature manure can be applied 10 days before plum sprouting (early April).

(2) topdressing after anthesis: quick-acting nitrogen and potassium fertilizer should be applied in time to reduce physiological fruit drop. 0.5 kg should be applied to the plant from late May to mid-June.

(3) topdressing in the period of fruit expansion and flower bud differentiation: from the physiological drop to the period of rapid expansion of the fruit (from late June to mid-August), the compound fertilizer of available nitrogen, phosphorus and potassium was applied, and 0.5 kg was applied to the plant.

(4) topdressing in the later stage of fruit growth: topdressing during the period from fruit coloring to harvest. This time, it is mainly phosphorus and potassium fertilizer, and the foliar spraying of available nitrogen fertilizer is better, and the concentration is 0.2%, combined with spraying.

(2) Irrigation

Plum trees need a certain amount of water in all phenological periods of the year. Before sprouting and young fruit expansion, irrigation should be carried out during the growing period of new shoots, and frozen water should be irrigated once before winter. In addition, plum trees are afraid of waterlogging, so plum orchards should repair the drainage system to avoid waterlogging.

Third, shaping and pruning

(1) Tree shape

Natural happy shape and double-layer open happy shape are often used in the tree shape of plum trees. Nature

The happy shape is characterized by ventilation and light transmission, high seed setting rate of the inner chamber and lower branch group, long life and easy management. The structure of the double-layer open happy tree is that there are 3 main branches on the first layer, the distance between the layers is about 80 cm, and 2 main branches on the second layer.

(2) pruning

1. Young tree stage

① natural happy shape: cut and dry at 40cm to 60cm above the ground in the same year. The first bud under the cut should be facing the wind (southwest), and the cut should be beveled. The upper part of the bevel is slightly higher than the tip of the bud, and the lower part of the slope is flat or slightly higher than the base of the bud. In the spring of the following year, three or four branches distributed around the newly issued branches in the same year were selected as the main branches (if not enough, they can be selected next year). The angle and distance between the main branches are shown in the figure. If the angle of the branch is unreasonable, it can be corrected by pulling or hanging branches. The dense branches are removed, and the undense branches are reserved as auxiliary branches. According to the growth of the main branches, cut off the full length of 1, 4, 1, 1, 3. In the third year of spring pruning, one angle was selected from each main branch, and the strong growing branch was used as the long branch of the main branch, and about 1 / 2 of the whole branch was cut off. In the lower part of each main branch, 1 to 2 outward growing branches were selected as lateral branches, and about 1 / 3 was cut short. The branchlets less than 5 cm on the main branch should be kept as much as possible and cultured into short fruit branches or bouquet-like fruit branches, with medium and long fruit branches properly truncated. In this way, the tree shape has been basically determined after 3 to 4 years, and the pruning method of the extended branches of the main and lateral branches is the same as that of the previous year.

② double-layer open happy shape: this kind of tree is suitable for varieties with strong growth potential and upright tree potential. The height of the fixed stem in the same year is 40cm to 60cm. In the spring of the following year, the upright branch with strong growth at the top was selected as the central leading trunk, and then the branches with 3 or 4 good angles were selected as the first layer of main branches, and the angles between the main branches and the trunk were about 50 °and 60 °. Other erect branches can be thinned, and medium and short branches should be retained as fruit branches. When pruning in the spring of the third year, 1-2 angles were selected on the main branches selected last year as lateral branches and elongated branches, and 2 or 3 main branches were selected on the central trunk as the second layer, which were staggered with the first main branch, and the distance between the two layers was 50-60 cm. At the same time, the central trunk will be happy to drop its head. Other branches are trimmed in the same way as the natural happy shape. It can be formed in 3 to 4 years.

2. Full fruiting period

By using the method of often changing the head of the backbone branch, the size of the tree should be controlled, the upper branch and the outer branch should be thinned and retracted, that is, the density should be sparse, the branch should be strong, the retained branch should be released slowly, and the branch should be retracted at the suitable branch next year. reduce the outer branches and leaves, improve the light conditions of the inner chamber and lower layer, ease the growth potential of the upper and outer parts of the crown, and the fruiting branches should be weak and strong. Reinvigorate and rejuvenate in planned stages and batches, and control its density and length. Remove dense branches, cross branches, disease and insect branches and thin branches, in order to save nutrients, ventilation and light.

3. Aging period

Rejuvenate the main and lateral branches in time, and the branches that are too long or too old should also be retracted properly. After retraction, it can generally germinate more strong branches and cultivate new backbone branches and branch groups to form a new crown.

(3) Summer pruning

Summer pruning refers to pruning in the growing season, which is generally carried out from mid-June to early July.

① coring: the growing point of the branch is removed during the growth period, and the specific time should be determined according to the variety, cultivation conditions and purpose. ② twisting: the tip of the new shoot is sprained, but not broken. Generally valuable twigs can be used to inhibit growth. Twisting should be carried out when the growth length of the new shoot is long enough, and the sprained site should be in the semi-Lignification area. ③ girdling: when the growth of new shoots is nearly stopped, the trunk or branches of prosperous trees are peeled in a ring with a width of about 1 / 10 of the diameter of the strips, and the effect of promoting flowers is obvious. ④ twig: hold the middle and lower part of the branch with your hand and hold it repeatedly, so that the branch tissue is damaged and grows horizontally or obliquely. The application of each measure of summer pruning should grasp the correct time and implementation object (young trees or prosperous trees that do not bear fruit), and remove overgrown, sprouting and withered branches during summer pruning.

? IV. Pest control

The main diseases of plum trees are plum red spot disease, plum gum disease, and insect pests are plum heart borer, aphids, red spiders and so on.