Practice of stable yield, quality improvement and Regeneration of Old trees in Pear Orchard

Practice of stable yield, quality improvement and Regeneration of Old trees in Pear Orchard

1 the transformation method of pear orchard

1.1 Tree reconstruction

Adjust the tree structure: there are 6 main branches, 4 main branches in the first layer, 3 branches in the second layer, and 3 branches in the upper layer. The crown width of the upper layer is less than that of the lower layer, and the interlayer auxiliary branches are cleaned. The height of the tree is controlled at about 4 meters, and the double layers are happy (Fig. 1, Fig. 2).

Fig. 1 the pear tree is happy with its head down.

Fig. 2 modified aerial picture of Liyuan

1.1.1 lift the stem to remove the floor mop and drooping branches, and raise the trunk to 0.81m.

1.1.2 the number of upper main branches was more than 4, and the length of upper main branches was more than 1 / 3, and the major operation of thinning and retraction was carried out within 2 years. The length of the upper main branch is less than that of the lower main branch, and the optical path of the upper layer is opened.

1.1.3 if there are too many auxiliary branches between layers, remove some of them, grow too long auxiliary branches, and retract so that the distance between layers is not less than 1.5 meters. Light-blocking auxiliary branches and residual piles are thoroughly removed.

1.1.4 as a result of the branch group transformation, the multi-axis extension of the branch group is uniaxial extension. Stroke: lengthen the head of the branch group and cut it gently and smooth it. After 2 ~ 3 years of elongation and weakness, the branches or buds on the oblique back were retracted to make the elongation head, smooth the nutrient transport channel and keep the branch group exuberant all the time. Sparse: that is, to remove thin, weak or overdense branches. The combination of thinning, heavy cutting and breaking fruit table shears are used to stimulate germination and cut buds to form flower buds or short fruit branches next year. Approach: retract mainly, in order to be close to the fruiting axle branch, to shorten the way of nutrition transport, improve the effective utilization rate of nutrition, and reduce the harm of gale to fruit.

Lower the back: for the large and straight branches on the back, in line with the principle of lowering the back, promoting both sides, and magnifying the back, change the erect branch group to oblique or thinning to improve the inner chamber lighting conditions.

Through year by year adjustment, there are mainly oblique medium and small branches in front and back of the main branches, and medium and large branches in the middle, so as to increase the sharpness of the main branches. At the same time, the group of weak twigs under the back of the main branch was gradually removed.

After the adjustment, the pear trees in the pear orchard basically formed a tree structure with layers of ventilation, visible light on the branches, and overall ventilation and transparency.

1.2 temporary plant modification

Distinguish between permanent and temporary plants, and gradually control the temporary plants until they are removed. Improve the population light of pear orchard.

1.3 Inter-line transformation

Retract the main branch. If the main branches between rows and plants have been handed over, the extension head should be reserved for retraction to ensure a light path of 1.5 to 2 meters between rows.

1.4 matters needing attention in the transformation of pear orchard

Carried out year by year, moderate intensity, pay attention to summer pruning management.

2 Flower and fruit fine management

2.1 pollination

Yali pear, Huangguan pear and horseshoe yellow pear were selected as pollination varieties of Dangshan pear. The suitable temperature for pollen treatment is 20: 25 ℃, and the relative humidity is 70% and 80%. Artificial pollination can be carried out when the crisp pear blossoms by 30%. In order to resist bad weather and improve fruit quality, early and middle ripening pears such as Huangguan should also strengthen artificial pollination.

2.2 thinning fruit

Fruit thinning begins 15 days after falling flowers, and the amount of fruit retained can be determined according to the variety, management level and tree potential combined with production experience, generally according to the yield of 2 000 to 2 500 kg per mu, mainly single fruit.

2.3 bagging

Choose high quality yellow single-layer bags or outer yellow double-layer bags (figure 3). Spraying once before bagging is mainly used to control pear planthopper, yellow pink aphid, Kang's pink scale, black spot and so on. At the same time, pay attention to the addition of high-quality and efficient calcium fertilizer.

Fig. 3 fruit bagging

2.4 other

Do a good job of anti-freezing, pre-flowering re-cutting, flower thinning and other work. Through transformation and fine management, the tree is strong and fruitful (figure 4).

Fig. 4 the result of the modified pear orchard

3Green prevention and control of diseases and insect pests

3.1 Agriculture and ecological control technology

Timely removal of diseases and insect pests and fruits; strengthen the management of pear orchards, enhance tree potential, improve the permeable conditions of pear orchards; clear ditches and drain in time.

3.2 trapping and killing techniques

Pear orchard hanging pear small trap (figure 5), pear small isotropic silk (figure 6), insecticidal lamp (figure 7), yellow trapping board, trunk winding yellow adhesive tape, trapping pear heart borer, pear planthopper adult and so on.

Fig. 5 small pear trap

Fig. 6 pear isotropic silk

Fig. 7 suction solar energy insecticidal lamp

3.3 Biological control technology

Promote biological agents to protect and utilize natural enemies.

3.4 techniques of induced disease resistance in plants

The stress resistance of pear trees was improved by spraying brassinolide, amino acid water-soluble fertilizer and amino oligosaccharins.

3.5 Chemical control techniques

The rotational use of pesticides can delay the resistance to pear diseases and insect pests. Spraying is strictly prohibited during the safe interval.

3.5.1 the pear trees mainly controlled anthracnose, ring streak, pear heart borer, pear planthopper, two-spotted leaf mite, yellow pink aphid, pink scale and so on.

3.5.2 according to the change of weather and the occurrence of diseases and insect pests, chemical control should be carried out in time.

3.5.3 full-complex mancozeb, carbendan, thiophanate-methyl, pyrazole carbendazim, difenoconazole, tebuconazole, etc.; insecticides include spiroethyl ester, methotrexate, matrine, methoxyhydrazide, chlorobenzamide, flurosemide, cyhalothrin, Bacillus thuringiensis, thiazine, etc.; acaricides include buflurate and spiromites (figure 8).

Fig. 8 mechanized spraying of pear orchard after modification

4. Pear orchard management under trees.

4.1 soil improvement

Adopt the recommended or natural grass method (figure 9) [Jishan Huayao], mow twice a year, turn once in 1 ~ 2 years, and dig at a depth of 20cm to 30cm; make full use of rape stalks, wheat stalks, corn stalks, wheat bran, weed stalks and orchards to cover tree plates with a thickness of 15cm and 20cm. After covering the grass, press a small amount of soil on the grass to prevent the wind from blowing and burning.

Fig. 9 Grass growing in pear orchard

4.2 soil testing and formula fertilization

According to the growth characteristics of pear and the detection results of soil nutrients, the formula fertilizer of pear was designed and used reasonably. Increase the formula base fertilizer, apply 400 kg formula base fertilizer per mu, and apply it in autumn. Topdressing: once a year, applied in mid-late June. The method of multi-point point application is adopted, the depth of the hole is 20 cm, and the formula topdressing is about 40 kg per mu.

4.3 Water management

In general, water is irrigated before budding, during fruit expansion and before freezing. However, when the leaves of pear trees wither during the growing season, they need to be irrigated. Furrow irrigation, border irrigation and micro-spraying can be used (Fig. 10). There is a drainage system in the pear orchard to drain in time in the rainy season.

Fig. 10 slight spray in pear orchard