Pruning technique of navel orange

To fix and change a thing, not because it is bad, but because it wants to develop better. The same is true for the pruning of flowers and trees. Although the flowers have bloomed beautifully and luxuriantly, they need to be trimmed if they want to be better and make people enjoy more beauty.

Pruning technique of navel orange

1. Pruning methods of navel orange young trees

In order to cultivate the tree crown, it should be cut lightly to avoid too much thinning and heavy cutting.

On the basis of the fixed trunk of the seedlings, the main branches were cultivated in the first and second years, and the auxiliary main branches and lateral branches were selected, and the elongated branches of the main branches and secondary main branches were cultivated in the third year, and the lateral branch groups were arranged reasonably. If the dense branch tip is thinned properly, the inner bore branch and the weaker branch tip in the middle and lower part of the crown should be retained. All the late autumn shoots drawn after September 10 were cut off.

Second, the pruning method of the initial result of navel orange.

Continue to cultivate and expand the crown, select and cut short the extended branches of all levels of backbone branches, and bear fruit in an appropriate amount. The branch group after retraction or truncation. Leave 15cm to 25cm for excessively long vegetative branches.

Erase the early sporadic sprouting buds before each shoot release to achieve neat shoot placement.

The last autumn shoots should be put together in mid-late August, and all late autumn shoots should be cut off after September 10. Give priority to light cutting to avoid excessive thinning and heavy cutting. Appropriate thinning and deletion of dense branches, to disturb the tree shape of overgrown branches and erect branches cut off from the base. Pay attention to the use of long branches, through pulling branches, short pruning to fill the gap in the crown.

Third, the pruning method of navel orange tree in full fruit period.

To maintain the relative balance between growth and fruit, the height of the tree is generally controlled below 3 meters, the thickness of the green leaf layer is about 1 meter, and the crown coverage is 75% to 85%. Retract the fruiting branch group, the falling flower and fruit branch group and the declining branch group in time.

Cut off withered branches, disease and insect branches, and thinly delete clump branches. For the trees with too many backbone branches and serious crown closure, the big branches which are too dense or improperly positioned at the base should be cut off by the big branch pruning method to maintain ventilation and light transmission.

Most of the multi-flowering trees were thinning and deleting flower branches and delicate branches. last year, the mother branches of autumn shoots reached the base to promote new shoots, and the combination of thinning and cutting. The trees with few flowers and prosperous trees are cut lightly, and only some erect vegetative branches are deleted to facilitate the fruit.

Fruit preservation method of navel orange

1. Spray 0.15% Huangjia natural brassin on the leaves after flowering to the second physiological fruit drop stage and add 5000 times of new nutrient liquid fertilizer such as L, P, K extract of sunflower seed, chlorophyllin, etc.) for 2 to 3 times.

2. Erase Xia Xiao, every 7 to 10 days.

3. Continue pruning, mainly thinning, improve the ventilation and light transmission conditions of the crown, cut off dead branches, disease and insect branches, and reduce the source of disease and insect infection.

In April, from mid-late May to early June, antixanthate was applied to prevent umbilical yellow fruit drop.

Fertilization methods of navel Orange

1. Ring ditch fertilization: according to the size of the crown, take the trunk as the center, open a ring ditch near the outer edge of the crown, the depth of the ditch depends on the depth of the root distribution, generally 20 cm to 30 cm deep and 30 cm wide. The advantage of circular fertilization is that it is fertilizer-saving, simple and easy to do, but it has a small area and is easy to hurt roots, so it is often used to fertilize young trees.

2. Radial fertilization: according to the size of the tree crown, dig 4-6 radial trenches in the tree plate, with a width of about 30 cm, which should be shallow near the trunk and deeper outward. In this method, the root injury is less, and the fertilization site is changed every other year or every other time to expand the fertilization area.

3. Strip trench fertilization: strip trenches are opened between rows or plants of navel orange trees, 30 cm deep and 30 cm wide, and filled with soil after fertilization; alternating ditches between plants and rows year by year, which is suitable for adult navel orange orchards, especially for closed navel orange orchards.

4. Hole fertilization: evenly dig 8 holes at the outer edge of the crown, with a depth of 20 cm and a width of 30 cm. Fertilizer is applied into the hole, and then cover the soil after infiltration. The method of hole fertilization is simple, the root injury is less, but the fertilization area is small, so it is suitable for the application of liquid fertilizer.

5. fertilization in the whole garden: spread the fertilizer evenly over the whole garden, and then turn it into the soil. It is suitable for navel orange adult orchards with roots all over the orchard, but the fertilization depth is shallow and it is easy to lead to root growth, so it should be used alternately with other methods.

Main diseases of navel orange

1. Fruit cracking disease

First of all, varieties (lines) with strong crack resistance should be selected. generally, varieties (lines) with oval fruit shape, small navel or closed navel have better crack resistance, such as Newhall, etc. Secondly, scientific management should be strengthened and tree potential should be strengthened. especially in the dry period from plum rain to autumn rain, we should do a good job in water management, irrigate or spray water in time, and often keep the soil moist to promote the normal growth and development of fruits. Thirdly, foliar potash fertilizer was sprayed for 3 times in the period of rapid fruit expansion. Foliar potash fertilizer can choose 0.2% potassium dihydrogen phosphate or 0.3% potassium sulfate compound fertilizer, and in the first and middle of July, the mixture of "920" with a concentration of 200 mg / L and 800 times of methyl topiramate and an appropriate amount of fragrant paste can heal the cracks and prevent fruit cracking from happening again.

2. Sunburn

Strengthening scientific management and protecting soil moisture by covering straw in orchards is the basis for preventing sunburn; planting forage grasses or interplanting green manure in orchards can reduce sunburn; in hot seasons, do not spray pesticides such as oil emulsion and stone-sulfur mixtures to avoid aggravating the occurrence of sunburn. In the early stage of sunburn, stick white paper on the sunburn fruit surface, and pull branches and leaves to block the fruit to reduce direct sunlight exposure. Regular irrigation or spraying in high temperature seasons in summer and autumn can prevent and reduce the occurrence of sunburn.

3. Umbilical yellow disease

First of all, we should start with the cultivation of healthy trees, appropriately increase the application of nitrogen fertilizer to improve the nutrition level of the trees, and then pull the Qiangwang autumn shoots into a drooping or horizontal state before flowering, so as to make the vast majority of flowers face down when they bloom, reduce sunny fruits and prevent the production of navel yellow. Once again, from the first ten days of June to the last ten days of July, combined with fruit protection, the "920" solution of 40 mg / L was sprayed twice, and from late July to late August, 600 times of "xanthate" solution was sprayed on the navel of the fruit to restrain the occurrence and spread of umbilical yellow disease.

The purpose of pruning navel oranges is to remove some branches, fruits and seeds that are not strong enough, and concentrate nutrients on those more robust branches in order to produce more fat fruits. In addition to pruning techniques, some of the pest control, fruit protection and fertilization techniques described in this paper are also very effective.