The latest course of High-yield cultivation techniques of Sugar Citrus

Sugar orange has the characteristics of early fruiting and high yield, pure sweetness and residue, which is suitable for the consumption habits of Chinese people, and its market price is 2 times higher than that of other oranges. The main techniques of planting and management of sugar orange are introduced as follows.

Select pure disease-free and insect-free strong seedlings

The early-maturing varieties have good quality and high yield. The seedlings with Fructus Aurantii as rootstocks are dwarfed early and prolific, and the seedlings with sour tangerines as rootstocks are upright and prosperous, and put into production late. The height of the seedling is more than 40 cm, the thickness is more than 5 cm, there are no quarantine diseases and insect pests (canker, Huanglong disease), the fibrous root is well developed, and the scion and rootstock have good compatibility.

Proper selection of land and reasonable close planting

Sugar orange can grow and bear fruit normally on the same soil quality, but for fast growth, early fruit, high and stable yield, it requires a moist and fertile soil environment, so to develop the cultivation of sugar orange, it is necessary to choose paddy fields with convenient transportation, sufficient water, irrigation and drainage, deep pine and fertile soil, early land, alluvial land by the river, and trough land. In order to achieve the purpose of high yield in the early stage, the method of dwarfing and dense planting was adopted in fertile paddy field and dry land, with 200 trees per mu and row spacing of 2 m × 1.5 m or 2 m × l m. About 100 plants per mu are planted in the mountain area, and the row spacing is 3 × 2 meters. Production practice has proved that dwarfing and dense planting is an important technical measure to realize early fruiting and high yield of sugar orange. Cross shading occurs after many years of high yield in dense planting garden, and then thinning is carried out.

Planting method

Sugar tangerines are generally planted from February to March in spring. Sand sugar oranges are developed on fertile paddy fields and riverside alluvial soil, which can be planted in shallow pits, while paddy fields should be arranged in high beds according to plant rows. For dry land and sloping land with poor soil quality, it is necessary to dig a deep pit of 1 meter square and prepare sufficient base fertilizer. Each pit applies 3 jin of phosphate fertilizer, 5 jin of lime, 100 jin of garbage or pond mud, and 30 jin of pig, cow and chicken manure. When filling the pit, mix the fertilizer with the soil and then fill it back into the pit. The tree plate is about 20 cm higher than the ground. Before planting, cut off some branches and leaves of the seedlings to reduce water evaporation, cut off the main root and retain the fibrous root as much as possible. When planting, dig a shallow hole to let the fibrous root stretch naturally, and then return to the soil to compact the soil. The height of the buried soil can not be buried beyond the joint of the graft. After planting, cover the tree plate with straw or other weeds and sprinkle it with rooting water. Within a month of planting, it is necessary to keep the soil near the root system moist, high temperature, sunny for a long time, dry soil, drenched with water every day, rainy days, when the soil is moist, there is no need to drench water.

Management of young trees

1. Fertilizer and water management

Young tree management takes fertilizer and water management as the center, promoting root growth, early branch growth and rapid development, and the early formation of tree crown. After 40 days of planting, the new roots began to grow, which could be diluted 3 times with rotten manure water and applied every 10 to 15 days, 5 kilograms per tree. With the growth of young trees, the concentration and dosage of manure water were gradually increased, and urea was properly added to dissolve in fecal water and then drenched. From the second year of planting, the number of fertilization can be reduced and the amount of manure can be increased each time.

And the amount of chemical fertilizer, 30 jin of manure and 3 taels of urea are applied each time. In September, stop applying nitrogen fertilizer and dung water, apply potassium fertilizer once, and apply potassium chloride half a jin per plant to promote flower bud differentiation. At the same time, attention should be paid to soil moisture management.

2. Shaping and pruning

The purpose of shaping is to make the sugar orange tree have a reasonable skeleton and a good tree shape with evenly distributed branches, so as to facilitate ventilation and light transmission, three-dimensional fruit, reduce the damage of diseases and insect pests, and lay the foundation for early bearing and high yield. The natural happy shape is generally adopted in the shaping of sand sugar orange. After planting, the trunk is cut short at 40 cm, and after it is sprouted, three branches with different directions are selected as the main technique. The angle between the main technique and the vertical line of the trunk is 45 °, and the main branch is too upright. The angle of the branch should be enlarged by rope. When the main branch is ripe, it will be cut short after 30 cm, and then three deputy main branches in different directions will be selected on the main branch. In the future, this method can be used to lengthen the bone in the branches of the tree. The erect branches planted on the main branches, secondary main branches and other backbone branches should be cut off, and the weak branches should be properly retained as auxiliary branches. The sprouting power of sugar orange is strong, and the branches are relatively dense. Each shoot is generally left with 3-4 shoots, and all the redundant ones are removed. In order to make the summer and autumn shoots neat, it is necessary to wipe the buds and control the shoots, that is, when there are only sporadic branches in the whole garden, wipe off the buds and stimulate the lateral buds to sprout until 80% of the branches sprout in the whole garden, so as to facilitate the prevention and control of diseases and insect pests.

Fruiting young tree

1. Fertilizer and water management. Young fruit trees were applied three times: stable fruit fertilizer, after Xiehua tree consumed a lot of nutrients, should be replenished in time, 50 jin of dung water per plant, or half jin of compound fertilizer and urea.

(2) strong fruit fertilizer. From July to August, the fruit expanded rapidly, and in the early stage of autumn shoot, nitrogen, phosphorus and potassium were applied together with 1 jin of compound fertilizer and half jin of urea and potash fertilizer per plant.

(3) Fruit picking fertilizer. Replenish the nutrition of the tree, restore the crown, and apply 50-100 jin of rotten dung water per plant. Every year, after the autumn shoot is ripe, it begins to make water and fertilizer to control the winter shoot and promote flower bud differentiation.

2. Reasonable control and pruning

After Shatang tangerine began to hang fruit, the vegetative growth was still relatively prosperous, and spring and summer shoots competed with flowers and young fruits for nutrients, resulting in flower and fruit drop. Autumn shoot is the fruiting mother branch of sugar orange, so measures are taken to thinning spring shoot, controlling summer shoot and promoting autumn shoot in production. Remove some spring shoots and reduce nutrition loss. When the summer shoots are sprouted, the buds are wiped off completely by manual method, or they can be sprayed with paclobutrazol 500-000ppm to control the summer shoots. In the first and middle of August, autumn shoots should be released uniformly, and attention should be paid to the prevention and control of diseases and insect pests to ensure the normal growth of autumn shoots. Young tree pruning is divided into summer pruning and winter pruning. The main purpose of summer pruning is to remove straight Z trees, cross branches, disease and insect branches that disturb the shape of the tree. Winter shearing should retract and prune the fruiting branches and deciduous branches to prevent excessive crown growth and premature senescence of branches. At the same time, cut off the disease and insect branches, cross branches, upright branches, and cut off the branches that are too dense at the top of the crown to open the skylight and increase ventilation and light.

3. Protecting flowers and fruits and thinning flowers and fruits. If the number of fallen fruit is too large or even few are left, if it is an abnormal drop, comprehensive measures should be taken to protect the fruit:

(1) remove some spring shoots and all summer shoots.

(2) applying moon stabilizing fertilizer in time.

(3) spraying mixed fruit protectants 10 days before the first and second physiological fruit drop, 50ppm920 plus 0.3% potassium dihydrogen phosphate or 920 plus organic foliar m.

(4) cut a circle in the upper ring of the trunk during the flowering period.

(5) Prevention and control of diseases and insect pests. If there are too many fruits, the weight and flavor of the single fruit will be reduced, thus affecting the sales price. It is necessary to timely thinning flowers and fruits, and thinning flowers should be carried out at the bud stage. Fruit thinning is carried out after the first and second physiological fruit drop. In the first time, the number of fruit was retained by 3 times the amount of fruit retained, and in the second time, the amount of fruit was retained by 1 more than the amount of fruit retained. Remove diseases, insect pests, deformed fruits and poorly developed young fruits. The amount of fruit retained by sugar orange is mainly determined by tree potential and fertilizer and water conditions.

Pest control

There are many kinds of diseases and insect pests in citrus. The symptoms and control methods of several main diseases and insect pests are introduced below:

1. Scab. It mainly harms tender branches and leaves and young fruits. The leaves infected with the disease began to appear watery spots, and then turned into waxy yellow. Many verrucous protuberances often grow after the fruit is damaged.

[control method] when the spring buds germinate 1 cm, spray 50% acetaminophen 500 times or 70% methyl topiramate 800 times. The second time, at the end of flower thanks, spray 70% methyl topiramate 800 times solution.

2. Anthrax. Anthrax is mainly characterized by red spots under rainy and high temperatures, black spots and rims under dry conditions.

[control method] spray twice at the tender shoot stage and young fruit stage, 0.5% equivalent Bordeaux solution, or 50% acetaminophen 500 times, or 70% methyl topiramate 800 times.

3. Huanglong disease. The main symptom is that in addition to the appearance of yellow shoots, the main feature of identifying the disease is yellowing at the base and margin of leaves and irregular yellow-green mottled leaves.

[control methods] ① selected disease-free seedlings and planted in isolated disease areas. ② strictly controlled the disease vector, citrus planthopper, and sprayed omethoate 1000 times, aphids 2000 times and imidacloprid 2000 times at each shoot stage. ③ rules the diseased tree, dig it out in time, and eliminate the source of the disease.

4. The mites are mainly red spiders and rust wall lice. The red spider harms the leaves, fruits and tender shoots, and the injured leaves lose their luster and are gray-white. Rust tick mainly harms the fruit and causes black fruit.

[prevention and control methods] clear the garden with Baume 1 degree stone sulfur mixture in winter. Acaricides such as triclofenac, Jinba mite, isocarbophos, propargite and other acaricides can be sprayed in turn in the growing season, once every 7 to 10 days, 2 times in a row.

5. Control of rust wall lice. Starting from June every year, observe the population density and spray immediately when there is a rust wall louse damage, using the same drugs as those used to control red spiders.

6. Scale. There are mainly cotton scale, shield scale and so on, which weaken the tree potential, induce soot disease and reduce the yield and quality of fruit.

[control methods] clear the garden with 16-20 times turpentine mixture in winter, and cut off the insect branches. The key point of prevention and control is that the first generation nymphs were sprayed twice during the peak period from May to June, and the agents used were: 40% omethoate 500 times 800 times, 40% isocarbophos 800 times, these two drugs added 100 times engine oil emulsion, the effect is better. The scale kills 1500 times and the quick cull 1500 times.

7. Leaf miner. Commonly known as drawing insects and ghost strokes, the larvae sneak into the epidermis of the tender leaves to feed, forming a white curved insect path on the back of the leaves, and the leaves curl, especially in summer and autumn.

[control methods] wipe off sporadic shoots, uniformly release shoots, concentrate spraying, and start spraying for the first time in summer and autumn shoots and grains, once every 7 to 10 days, twice each time, using 1500 times of Keyobao and 2000 times of enemy killing. An Lubao 1500 times spray, spot potential ~ E 1500 times.