Summer orange is one of the dominant citrus varieties developed in Henan in recent ten years. According to statistics, the area of summer oranges in Guilin in 2007 was139,400 mu, of which the production area was 92 100500 mu and the output was 100500 tons, accounting for 10.25% and 7.78% of the citrus area and output respectively. Mainly distributed in Lipu, Yangshuo, Lingui, Pingle and other counties in central and southern China. The fruit maturity of summer orange is from March to May every year, which is in the off-season of fresh fruit supply and has a good market prospect. The key points of summer orange cultivation techniques are introduced as follows:

1, young tree management

(1) soil management

① reaming and soil improvement: dig a fertilization pit with a length of 1~ 1.2 m, a width of 40~50 cm and a depth of 40~50 cm along the outer edge of the fruit pit, and apply 20~30 kg of green manure and weeds, 20 ~ 30 kg of pig manure/kloc-0 ~ 15 kg of phosphate fertilizer to each plant. Combined with deep application of organic fertilizer, deep tillage and soil improvement are carried out 1~2 times a year, and the deep tillage position is continuously rotated, and the deep tillage task of the whole garden is completed in 3~4 years.

② Planting two-season green manure in the open space between rows.

(3) Plow and weed in the tree tray 3-4 times a year, and cover the tree tray in high temperature and dry season.

(4) In the rainy season, the flat orchard should be ditched and drained.

(2) Fertilizing young trees

For 1~3-year-old trees, the purpose of fertilization is to enhance the vegetative growth of trees, promote the emergence of strong branches, and make them expand rapidly to form high-yield trees. The principle of fertilization is: apply fertilizer frequently and thinly, eat less and eat more meals, give priority to nitrogen fertilizer, and properly cooperate with phosphorus and potassium fertilizer. Spraying with 10~20% decomposed chaff manure (or biogas slurry) and 0. 1~0.3% urea or 0. 1~0.3% compound fertilizer every 15~20 days/time. Apply "one branch and three fertilizers" to each new shoot, that is, fertilizer before germination (before germination 10 day), fertilizer for attacking shoots (when new shoots spread leaves) and fertilizer for strengthening shoots (after leaves turn green). Strive to shoot strong branches 3~4 times a year/kloc-0. Every time new shoots turn green, combined with pest control, foliar fertilizers such as Lv Wang 1 1000 times or 0.2% potassium dihydrogen phosphate are added to promote the aging of new shoots.

(3) shaping and pruning

① Plastic surgery: natural head-shaped trees should be adopted for summer oranges. Cut off the top of the trunk at a height of 30-40 cm and fix the trunk. After the new buds germinate, select 3-4 main branches with strong growth and uniform distribution, and the opening angle of the main branches is 40-45 degrees. There are 2-3 auxiliary main branches on each main branch, forming a good crown skeleton with strong bearing capacity.

(2) Pruning: shoot setting and shoot control: When the young trees 1 new shoots planted in that year are mature, during the summer and autumn shoots, it is necessary to wipe off the scattered new shoots that sprouted early, so that the new shoots will sprout neatly and healthily and reduce the harm of leaf miner and aphid.

Based on the characteristics that summer oranges shoot many times a year, young trees can shoot three or four times a year before 1~2 years, and only shoot three times in spring, summer and autumn in the third year. We should make full use of powerful summer buds, spring and summer buds and summer and autumn secondary buds. When it grows to 15~25 cm or has 8~ 15 leaves, it should be picked in time to promote the maturity of branches and accelerate the expansion of crown. Excess weak branches, trailing branches, cross branches and pests are cut off.

2. Adult fruit tree management

(1) Fertilization: Fertilize adult fruit trees five times a year, that is, base fertilizer 1 time and topdressing four times.

① Base fertilizer: In order to promote flower bud differentiation and reduce fruit drop in winter, base fertilizer should be applied well in advance, and the fertilization time should be165438+1mid-October. Fertilizer is mainly decomposed organic fertilizer. Generally, 25 kg of decomposed pig manure, 2~3 kg of phosphate fertilizer 1~ 1.5 kg of bran fertilizer are applied to each plant. Methods: Two opposite ditches were dug under the crown drip line, with a width of 30 ~ 40cm, a depth of 40cm and a length of 80 ~ 100cm. After the fertilizer is mixed with topsoil, it is put into into the pit ditch for soil remediation.

② Topdressing: 4 times a year, shallow furrowing or acupoint application along the crown drip line.

Germination fertilizer: applied before germination 10~ 15 days. 0.3 kg urea+0.5 kg compound fertilizer+15-20 kg bran fertilizer.

Fruit-stabilizing fertilizer: applied after flowers wither and before the second physiological fruit drop. Each plant is applied with 30 kg of decomposed human and animal manure+0.5 kg of compound fertilizer. At this time, foliar fertilizer can be sprayed outside the roots in combination with pest control, and sprayed every 10~ 15 days/time, 2~3 times in total. 0.3% urea +0.2% potassium dihydrogen phosphate or Lv Wang 1000 times or amino acid foliar fertilizer.

Strong fruit and promote shoot fertilization: apply it from mid-July to early August or before autumn shoot release 15 days. This period is characterized by the continuous expansion of fruit, forming the yield of the current year, pulling out the autumn shoots and forming the fruiting mother branches of the next year, which is another important period of fertilization. Full-effect fertilizer should be applied to increase the amount of potassium fertilizer. 0.75 kg of high-efficiency compound fertilizer and 0.3~0.5 kg of potassium fertilizer were applied to the plants.

Fruit picking fertilizer: apply it after fruit picking to restore tree vigor as soon as possible. Apply compound fertilizer 0.5~ 1.0 kg per plant.

(2) flower protection and fruit protection

① Apply plant growth regulator to protect fruit: after the spring shoots turn green, spray 8~ 10 unit (per gram 106 kg ~85 kg water) 2,4-drops and 0.2% potassium dihydrogen phosphate on the leaves of young fruits.

② Ring-tying or ring-cutting to protect fruit: For young and middle-aged trees with vigorous growth, ring-tying or ring-cutting should be carried out on the trunk or main branch at the early stage of physiological fruit drop after flowering, and for over-flourishing trees, ring-tying or ring-cutting should be carried out 15 days later, which can improve the fruit setting rate.

③ Sparse the spring shoots and wipe the summer shoots: when the young trees bear fruit or have few flowers, properly wipe off the excessive vegetative branches in the spring shoots. Adult fruit trees should be thoroughly smoothed in summer.

(4) Flower thinning and fruit thinning: flower thinning is carried out in bud stage. For trees with many flowers, leafless inflorescences and leafy flowers with more than 4 leaves should be thinned. Fruit thinning is carried out in batches after the second physiological fruit drop. Remove pests and diseases, deformed fruits and small fruits. Young trees prune the young fruits of the extended branches at the top of the main branches, and keep the young fruits in the lower part of the crown and the inner chamber. Finally, the ratio of leaf to fruit should be kept at 50 ~ 60: 1.

⑤ Spraying 2,4-D to protect leaves and fruits in winter: spraying 1~2 times of 20-30 units (50-33 kilograms of water per gram) 2,4-D plus 0.2% potassium dihydrogen phosphate before winter comes.

⑥ Where there is frost in winter, irrigation ("racing water"), tree covering, trunk painting and other anti-freezing work should be done well. Orchards with conditions should be covered with simple film in winter.

(3) Pruning

Therefore, trees should properly remove the vegetative branches of dense spring shoots, erase summer shoots and release autumn shoots at the right time. Pay attention to thinning the strong and upright branches at the top of the crown to promote the balanced growth of branches in all parts of the crown. At the same time, cross-bearing branches, pests and diseases are cut off to maintain good ventilation and light transmission performance of the tree.

(4) Prevention and control of pests and diseases

The main pests and diseases in the production of summer orange are canker, anthracnose, Huanglongbing, liriomyza sativae, mites, psyllids, whiteflies, bud maggots, aphids and so on. Pest control should master the principle of "prevention first, prevention is more important than cure", spray pesticides in time when pests are found, and completely eliminate the source of overwintering pests in winter. Every time a new bud germinates, it should be sprayed in time to kill all kinds of pests that harm the new bud, such as latent leaves, aphids, citrus psyllids, red spiders, bud maggots, whiteflies and so on. Make the new buds turn green and healthy normally. Use chemical agents to control pests and diseases, and use pesticides in turn to avoid drug resistance.

① Canker: Canker is the main disease of summer orange. Spray the medicine for the first time when the new buds grow to 2~3 cm, and then spray 1 time when they are "self-sheared". The medicament can be 500-600 times of 30% copper oxychloride, 300-500 times of 14% aqueous solution of cuprammonium chromate, 600-700 times of 77% metronidazole, 2000-3000 times of 72% streptomycin sulfate, 500-800 times of zineb, etc. , 2-800 times each time.

(2) Red Spider: Red Spider mainly harms leaves and young fruits, and weakens trees in severe cases. You can choose 1.8% avermectin 3000 times solution, 20% pyridaben 1000 times solution, etc.

(3) Deciduous moth: When the new bud grows to 0.5 ~ 2 cm, spray medicine to protect the bud. Spraying continuously for 2~3 times with an interval of 7~ 10 day. The following agents can be selected: 1.8% avermectin 3000 times, 2.5% deltamethrin (diphacinone) 1500~2000 times, 20% sandong 2000 times, and 24% methomyl (wanling)1000 ~ 60 times.

④ Huanglongbing: Dig out the diseased tree in time, spray the medicine first and then cut down the tree. Every time a new bud germinates until the bud is 5 cm long, it should be sprayed with chemicals to control citrus psylla. Spraying deltamethrin isocarbophos (26% insecticidal emulsifiable concentrate) or deltamethrin triazophos (22% acaricide emulsifiable concentrate) with 1000 times for 2~3 times to prevent citrus psylla from damaging shoots and spreading viruses.