Rootstocks were cultivated with sour pomelo or bitter orange, and were sown in June+10/October of that year. Choose a plot with easy irrigation and drainage and fertile land. Sow 20 × 15 (cm) rootstocks per mu, which can be grafted (single bud grafting or branch grafting) until July-September, and the scions are picked from sunny and robust spring shoots in that year. Wipe off the mature rhizome buds in time before picking them. When the second tip is mature, it can be untied and taken out of the garden. It can also grow to the third spring and come out of the garden.
2. Young tree management
On the basis of selecting seedlings and site conditions, it is necessary to establish a strong root system from the beginning of planting, rapidly expand the crown and cultivate strong trees. After reaching a certain growth, we should do a good job in promoting flower bud differentiation in time and implement measures to protect strong flowers and fruits, so as to achieve the goals of fast growth, fast growth, early fruiting and high yield.
1, Miao. Seedlings must be strong seedlings with developed roots, many fibrous roots and no pests and diseases. They are cultivated with sour pomelo seeds or bitter orange seeds as rootstocks and excellent spring shoots or autumn shoots as scions.
2. Site conditions. ① Deep soil, preferably purple shale parent material weathered soil (red loam); (2) Mountain areas with a slope of 5-25 degrees and good spatial utilization and permeability are used as orchards. (3) orchard (water, road, electricity) three links, easy to strengthen management.
Step 3 plant. ① The ridge size is 1× 1m or 1× 0.8m, and the planting size is 6× 5m. (2) After the base fertilizer and soil are evenly mixed and applied, a tree tray 30 cm above the ground is established on the ridge surface, and shallow seedlings are planted in the middle of the tree tray, which is beneficial to the growth of roots and promotes the rapid growth of young trees.
4. Fertilize. Newly planted young trees require new shoots four times a year, and each new shoot is fertilized twice, that is, shoot-promoting fertilizer and strong shoot fertilizer, and fertilized eight times a year. In summer and autumn, due to the vigorous growth of young trees and irregular branches, it is more convenient to use manual wiping management.
5. Enlarge the pit and dig deep to improve the soil. In the autumn and winter of the second year after planting, a ditch with a depth of 0.6 meters was dug at the edge of the crown, and garbage manure, green manure and straw were applied. , and add 1 kg phosphate fertilizer and 0.5 kg lime. With the growth of tree age and the expansion of crown, the amount of fertilizer will increase year by year.
6. Fixed stem and crown cultivation. (1) Young trees should be cut off after four transplants, and other branches should be cut off within 40 cm from the ground to establish the trunk. ② Cultivation of dental crowns. In principle, young trees should be pulled, and the branches should be pulled in the direction where there is room for growth, so as to establish a body shape with uniform growth of primary and secondary branches. ③ Control pests and diseases, mainly canker, liriomyza sativae and red spider.
3. Flower bud differentiation management
The physiological differentiation of flower buds began in late September, and was relatively concentrated in the middle of 10 to 12. This stage is mainly to increase the concentration of juice, increase the accumulation of nutrients in the tree, and promote the differentiation of bud primordium into flower buds. With flowers, the measures to strengthen flowers and protect fruits can be implemented.
1, flower bud differentiation conditions: only the tree itself has the nutrient accumulation of flower bud differentiation, that is, its bud is mature, and under relatively low temperature or dry environmental conditions, the bud primordium can differentiate towards the flower bud to form flower buds.
2. Flower bud differentiation period: it first appeared at the end of September, and a few flower buds began to differentiate until the end of 65438+ 10, which lasted for 4 months, but it was relatively concentrated from the middle of 65438+ 10 to the middle of 65438+February, and reached the peak of differentiation at 65438+ 10.
3. Measures to promote flower bud differentiation:
(1) Strengthen fertilizer and water management and cultivate strong trees. (1) For young trees bearing fruit in the second year, autumn shoot fertilizer mainly containing organic matter should be applied in the middle and late July, and phosphorus and potassium fertilizers should be sprayed outside the roots before and after the autumn shoots turn green. (2) Autumn shooting should be released in early August, and it should be adapted as soon as possible without causing winter shooting. (3) For trees with many fruits and weak tree vigor, autumn shoot fertilizer should be applied again to promote the rapid turning of autumn shoots into green, full and robust, so as to restore tree vigor and accumulate nutrients for flower bud differentiation.
⑵ Reasonable pruning. Protect excellent fruiting mother branches and promote flower bud differentiation.
(3) water production. The most effective way to promote flower bud differentiation is to make water; After the autumn shoots turn green, the water supply should be reduced to promote the autumn shoots to mature as soon as possible, and the juice concentration should be increased, which is beneficial to the accumulation of carbohydrates and flower-forming substances in the trees and to enter the flower bud differentiation stage in time.
Cut the roots. Generally, it is carried out after the autumn shoots turn green 10 month. The way to cut the roots is to dig a ditch at the drip line of the crown. The size of the ditch depends on the size of the crown. Generally, it is1.5 ~ 3.0m long and 40 ~ 50cm wide, and the paddy field pomelo garden (with shallow roots)15 ~ 20cm. If a single tree is thick and the horizontal roots are underdeveloped, it can be slightly widened into a crown. Try to cut off a few thick roots with a cut of about 65,438+0 cm, and let them be exposed for a period of time, and then cover the soil after the color of the leaves of the above water-making system changes. Orchard root cutting combined with deep ploughing and soil improvement (once every 2-4 years), ditch length, ditch width and ditch depth are carried out according to the standard of deep ploughing and soil improvement, and the effect of promoting flower bud differentiation after root cutting and sun drying is more ideal.
(4) ring or ring cutting. The time should be 10 month after the autumn shoots mature. First, the ring tie. In the smooth part of the trunk or main branch, tie the circle with 14 or 16 iron wire, and tie the iron wire tightly with iron tongs. The tightness should be that the bark under the wire has water stains, or the wire is embedded in 1/3. After 20 ~ 30 days, when the leaves start to turn green, the iron wire will be loosened. B, ring cutting. Cut the trunk of the tree 1 time with an ordinary electrician's knife, so as to cut only the bark layer of the tree without hurting the xylem. C. If yellow leaves or fallen leaves appear after girdling or girdling, water should be sprayed or sprayed on the leaves, and 0.3% urea solution should be sprayed on the leaves at a ratio of 2,4-d of1100000. Weak plants should not be girdled or girdled. 5] Remove winter buds. For the trees ready to bear fruit, the winter shoots growing from the first ten days of 10 to the middle period of 12 must be removed, and all nutrients should be stored in the original branches to promote flowering.
[6] Use hormones to promote flowers. Paclobutrazol and cytokinin were sprayed once in the middle of June 5438+ 10 and once in the late of June 5438+065438+ 10 to promote flower bud differentiation.
4. Strong flowers protect fruits
At this stage, fertilizer and water management and pest control are mainly strengthened to achieve the purpose of strengthening flowers and protecting fruits.
1. Cultivate robust tree vigor: To improve the fruit setting rate of Shatian pomelo, we should focus on the previous year. First, maintain a good tree potential. The second is to cultivate a certain number of strong branches to facilitate the accumulation of trees, and the third is to pay attention to protecting leaves for the winter.
2. Rational fertilization: (1)65438 Early budding+late February (from winter to the future), and nitrogen fertilizer should be the main fertilizer. ⑵ External fertilization: For pomelo orchards in acidic soil, zinc sulfate, magnesium sulfate and borax (or boric acid) 1 ~ 2 times should be sprayed. Sandy soil is easy to lack boron, which affects pollen germination, elongation and fruit expansion. Boron fertilizer should be sprayed properly. ⑶ Spraying 0. 1 ~ 0.3% ammonium molybdate 1 ~ 2 times on leaves in bud stage is beneficial to the formation of chlorophyll in new shoots, promoting photosynthesis and absorption of phosphorus and nitrogen, and improving flower quality. (4) At the beginning of June, strong fruit fertilizer was applied again.
3. Dewatering: In order to ensure that the flower organs and young fruits have sufficient nutrient supply, it is necessary to properly control the excessive growth of spring shoots, that is, to drain the young spring shoots at the top of the tree, so that they are relatively concentrated on the development of flower organs and young fruits, which is conducive to improving the fruit setting rate.
4. Sparse flower buds: In order to reduce unnecessary nutrient consumption, we can systematically and artificially sparse some flower buds while thinning some spring shoots, so as to concentrate nutrients, supply the remaining flowers and promote their robust growth and development. The specific methods are as follows: ① Sparse some inflorescences, that is, when the flower buds are as big as matchsticks, press 1 to bear 1 ~ 2 fruits on the mother branch. For a single plant with few flowers, only a part of the fruiting mother branches with too many inflorescences are thinned. ② During 1 0 ~ 1 5 days after flower thinning, when the flower buds are as big as soybeans, the top of the inflorescence and the weak flower buds are thinned, leaving only 2 ~ 3 robust flower buds in1inflorescence. (3) In the process of flower thinning, attention should be paid to make the remaining flowers evenly distributed in the whole tree crown.
5. Artificial cross pollination: (1) timely collect pollen. From the first flowering of Shatian pomelo, healthy flowers that have just opened or are about to open were collected from pollinated trees with normal growth and vigorous tree growth, and picked with flower stalks. The pollination tree is preferably sour pomelo or red meat chopping block pomelo. There are three pollination methods: ① Remove the petals and stigma, and put the pollen directly on the stigma of the vigorous Shatian pomelo flower. Generally, each flower can be endowed with 15 ~ 20 Shatian pomelo flowers. (2) Dip the pollen of pollinated trees with a brush, and then dip the stigma of the newly opened Shatian pomelo flower. If this method is adopted, the medicinal tweezers for pollinating flowers should be placed on a clean pot cover, dried slightly to make the anthers crack and the pollen disperse, and then collected and put into small bottles for later use. If you have to wait until the next day or the day after collection, you should pick the budding flowers and put them in a plate full of wet sand, but you can't keep them for too long. ③ Pollen liquid pollination: add 10 ~ 20 anthers of sour pomelo flowers in 50g of water, then add 2,4-5 ~ 6ppm, 20 ~ 25% honey and 0. 1% borax to make pollen liquid. Dipping pollen liquid with a clean brush on the newly opened stigma of Shatian pomelo flower can improve the utilization rate and fruit setting rate of sour pomelo flower.
(2) Pollination time. The best pollination time is 8 ~ 1 1 on sunny days, followed by 4 ~ 7 pm. Artificial pollination must be carried out in batches, first open and then give, then open and then give. Generally, according to the fruit setting rate of 30 ~ 40%, pomelo trees set fruit 100 and pollinate 300 ~ 450 flowers, which can be pollinated for 3 ~ 4 times.
6. Spraying growth regulators to protect fruits: Generally, from flower withering to the early stage of young fruits, 1 time 2,4-d is sprayed on young fruits at intervals of 1 5-20 days/time, and the concentration is 5-7 parts per million. Attention: ① It must be after the leaves of spring shoots mature, otherwise it will cause phytotoxicity. (2) The concentration of the prepared liquid medicine must be accurate, and it is easy to cause phytotoxicity if it is too concentrated. Therefore, the concentration must be strictly controlled and sprayed evenly during operation, and repeated spraying is not allowed. ③ If it is mixed with 0.2 ~ 0.3% urea or plant tonic, the effect will be better.
7. Let the bees shake the flowers:
(1) During flowering, beekeeping in Shatian pomelo orchard with pollinated trees is helpful to the spread of pollen. (2) In case of rainy days when in full bloom, you need to shake the big branches 1 time every 2 ~ 3 days to shake off the petals. 8. Removing summer shoots: The way to prevent summer shoots from sprouting is to apply fertilizer reasonably and avoid partial application of nitrogen fertilizer. Once it grows to 3 ~ 5 cm, it should be manually erased or removed.
9. Pest control: In flowering and young fruit period, the control of bud maggots, red spiders, midges, anthracnose, canker and scab should be strengthened. The above measures to strengthen flowers and protect fruits focus on strengthening fertilizer and water management and pest control. Spraying fungicides 7 days before flowering in old Shatian pomelo area to control the damage of germs to flowers.
Step 5: plastic trimming
Plastic pruning can enhance the growth potential of pruned branches (that is, promote bud germination or new shoot growth near the incision), but temporarily weaken the growth of the whole tree, which is the dual role of pruning. The pruning and shaping of Shatian pomelo should use all kinds of methods correctly, restrain the strong and help the weak, and promote the control correctly, so that the tree potential is balanced, the branches are clearly defined, compact and plump, the branches are thick, the crown is effectively branched, and the flowers and fruits grow healthily.
1. Young pomelo tree shaping: after the young tree is shaped, pay attention to cultivating 3-4 main branches, leaving 3-4 pairs of main branches for each main branch, and the crown should be multi-branched. ① Branching is the main method. (2) adhere to the unified prompt; Erase the sporadic buds that germinate prematurely. 70 ~ 80% of the plants in the whole garden should be erased once when they germinate, and then put out buds. ③ Bud fixing and shoot fixing: When the new branches are 3-6 cm long, remove the weakness and keep the strength, remove the straightness and keep the inclination, and keep 2-3 robust new branches on each basic branch, and pay attention to the reasonable distribution direction.
2. As a result, the grapefruit tree was pruned. Combined with clearing the garden in winter, pruning should be carried out immediately after picking fruit from the end of 10 to the middle of 1 10, so as to rejuvenate the tree and cultivate excellent fruiting mother branches. Results In early August, pomelo leaves spring shoots, at most autumn shoots, and all branches in other seasons are removed, which is beneficial to strengthen flowers, protect fruits and promote flowers. (1) Cut off dead branches, pest branches, overlapping branches and long branches in the tree cavity, and take back the overlord branches; Let the tree have enough sunlight to directly shine on the branches inside and outside, improve the resistance of the tree and promote flowering. (2) It is emphasized that when picking grapefruit fruit, a fruit is cut twice: the first cut is cut together with the fruiting branches, and the second cut is to cut off the fruit stalks on the grapefruit fruit. (3) Pruning weak pomelo trees should shrink branches, remove too many leafless branches and weak branches, reduce the flowering amount and nutrient consumption in the next year, and extract healthy spring shoots to rejuvenate the trees. In addition, the fallen flowers and fruit branches and leafless branches are cut off in spring and summer to achieve strong flowers and fruit protection.
6. Quality fruit management
The high-quality Shatian pomelo fruit should weigh more than 1 kg, with regular shape and bright surface, without insect spots and disease spots caused by pests and diseases. The soluble solid content (sugar content) reached 65438 04%. The taste is sweet and crisp, and there is no other miscellaneous taste.
1, controlling fertilizer and water: Shatian pomelo is tall and full of fruit, which requires high fertilizer and water management. How to improve the quality and provide the nutrition for grapefruit fruit? All strong fruit fertilizers should be applied before the first ten days of June; From late August, the use of available nitrogen fertilizer should be controlled. In order to increase the content of soluble solids, it is necessary to control fertilizer and water in paddy fields or lowland orchards.
2. Further improve the soluble solid content (sugar content) of Shatian pomelo fruit: Experiments have proved that peanut bran or rapeseed bran can promote Shatian pomelo to be rich in honey and sweetness, and phosphorus fertilizer can promote the fructose content (especially bone meal) of Shatian pomelo. Therefore, ① increase the application of phosphate fertilizer and organic soil miscellaneous fertilizer. (2) after retting 10 ~ 25 days, increase the application amount of peanut bran and bone meal, and advocate "one fruit, one two peanut bran (rapeseed bran) and half two bone meal", and apply it twice in early July and early August respectively. ③ Sterilization with thiophanate methyl or carbendazim during fruit picking, storage for a period of time and packaging are beneficial to increase the soluble solid content.
3. Fruit thinning: According to the fruit-bearing capacity of plants, the time should be completed from May to the end of June. In the young fruit period, the redundant young fruit, diseased fruit and deformed fruit are thinned by manual methods, so that pomelo fruits are evenly distributed in the crown and the commercial fruits are qualified when harvested.
4. Fertilizer promotion outside the roots: spraying Dayun 120, Santosu, Wanguobao or Gomez once a year from May to July. After August, phosphate fertilizer and potassium fertilizer are sprayed, such as Gaomeishi, Wang Lu 1 or potassium dihydrogen phosphate.
5. The main pests and diseases that harm the appearance of pomelo fruit are canker, rust tick, scale insect and scale insect.