Under the traditional cultivation technology mode, the yield of pomelo is low, the quality is poor, and the benefit is not ideal. In recent years, Sinan County has taken advantage of its unique geographical advantages to actively improve high-yield cultivation technology, so that the red pomelo has been continuously harvested. Therefore, it is an important measure to improve the yield, quality and efficiency of pomelo by applying high-quality and high-yield cultivation technology to the cultivation of pomelo and doing a good job in pest control.
1 Analysis of the key points of high-yield cultivation technology of red pomelo 11. The orchard site selection plan gives priority to deep soil, loose and breathable, strong water and fertilizer retention capacity, rich organic matter, and pH value of 55~6.5 sandy loam soils; There are no pollution sources around, convenient transportation, convenient drainage and irrigation, and no tall trees to block it. When planting pomelo in mountainous areas, it is necessary to ensure that the slope is 20°, and the slope direction is suitable for the sunny slope, which can reduce cold damage, maintain water and soil, ensure the light time, and help promote the healthy growth of the plant. Stay away from other citrus orchards as much as possible to prevent the spread of pests and diseases. After site selection, the orchard should be reasonably planned, focusing on the planning and construction of zoning, road system, drainage and irrigation system, shelter forest, and auxiliary buildings, so as to provide convenience and help for the cultivation and management of red pomelo.
1.2. The depth of soil ploughing and fertilization should be controlled at 25 30 cm, and the deep ploughing of the soil can kill some germs and insect eggs in the soil and improve the loose air permeability of the soil. After deep turning, dig the planting hole, the length is 1 m, the width is 1 m, the depth is 1 m, and 25 kg of green manure, 15 kg of rotten chicken manure and 1 cake fertilizer are applied at the bottom of the planting hole5 kg, superphosphate 05 kg, mix fertilizer with soil and backfill. Note that the surface layer of cooked soil should be backfilled to the upper layer, the plot should be made into a tile-shaped ridge, and a drainage ditch should be set between the two planting holes. 1.3. The grafted seedlings are selected as improved varieties of pomelo grafting, and it is recommended to introduce excellent pomelo scion to ensure that the seedlings have developed root system, strong growth and good growth, and the 1-year-old grafted seedlings are the most suitable. The local pomelo seedlings are selected as rootstocks, and the single bud cutting method is used for grafting operations, which has strong adaptability and recovery ability, and has a high survival rate after planting, which can form a good crown and achieve the purpose of early fruiting and yield increase.
1.4. Pay attention to the seedling treatmentBefore planting, separate the female and male plants, and properly prune the root system of the seedlings, cut off the excessively long roots, bad roots, rotten roots, etc., so as to promote the germination of new roots and reduce the probability of dead seedlings. If it is found that there is a nodule in the root of the seedling, sterilization and disinfection should be carried out, an appropriate amount of 50 warm water should be prepared to soak the root system for 5 min, and the root should be soaked with fungicide + rooting powder for 10 20 min, which can promote the early growth, multiple and fast growth of new roots while killing the germs. After treatment, the seedlings can be planted. 1.5. Scientific and reasonable dense planting should be combined with variety characteristics, soil moisture and other factors to adjust the density. Flat orchard, row spacing 3 m, plant spacing 4 m, planting density of 55 plants 667 m 2; Sloping orchards, using row spacing 35 m, plant spacing 4 m, planting density of 48 plants 667 m 2.
When planting, put the seedlings into the center of the hole and straighten it, backfill the fine soil to cover the root system, at this time lightly lift the seedlings, straighten out the root system, so that the root system and the soil are fully contacted. Continue to backfill the soil and steadily, and the height of the backfill should be 10 cm above the surface of the seedling root neck. Sufficient rooting water, after the water is dry, then cover with a layer of soil, and finally cover the grass or film to keep warm and moisturize to ensure the survival rate of seedlings. 1.6 timely topdressing fertilizer for young trees, to focus on tapping, tip protection, it is recommended to topdressing 6 8 times, each time each fruit tree topdressing nitrogen fertilizer 02 kg, phosphate fertilizer 01 kg, 25 kg of flush fertilizer. Digging an annular ditch and watering can effectively improve the fertilizer utilization rate and accelerate the formation of tree canopy. 3 weeks before the spring shoot germination of pomelo trees, it is necessary to apply flowering fertilizer, and it is recommended to apply 25 kg of rotting farmhouse fertilizer, 1 kg of urea, and 0 kg of calcium, magnesium and phosphorus fertilizer for each plant5 kg, potassium sulfate 1 kg, also dig an annular trench to apply. This top dressing, that is, combined with extra-root spraying, is recommended to spray 03% potassium monobasic phosphate +01% borax mixture. For fruiting trees, top dressing is done 4 times in the first year. Three weeks before the pomelo tree shoots, the fruit-strengthening fertilizer was applied, and each fruit tree was applied with 50 kg of rotting farmhouse fertilizer, 3 kg of bio-organic fertilizer, 2 kg of three-element compound fertilizer, and 02% potassium dibasic phosphate solution. After fruit picking, it is recommended to apply 80 kg of well-rotted farmhouse fertilizer and 0 urea per fruit tree5 kg, potassium sulfate 05 kg, magnesium sulfate 02 kg, zinc sulfate 01 kg。At the same time, 02% potassium dihydrogen phosphate + 03% urea.
1.7. Irrigation and drainage fruit farmers should improve their awareness of water management, and do a good job of watering or drainage in combination with factors such as natural precipitation in Sinan County, water demand of pomelo trees, and soil water content. For the irrigation of pomelo treetip growth stage, flower bud differentiation stage and fruit growth stage, the soil water content should be controlled at 60% and 70%. When watering, it is recommended to use drip irrigation and sprinkler irrigation, and it is forbidden to flood irrigation. If the rainy weather continues, the ditch should be cleared and drained in advance to avoid water accumulation affecting the breathing of the pomelo tree and hindering its growth and development. 1.8 Pay attention to pruning and shaping18.1. When the length of the main trunk of the seedling is 35 cm, the new shoots are extracted, and 3 or 4 strong new shoots are left as the main branches in combination with their growth conditions, and the length of each main branch is controlled, and the topping is plucked in time, and 2 branches are promoted as the secondary main branches, and the other long branches, cross branches, overlapping branches, etc. are pruned off to avoid affecting the light.
1.8.2. The initial pruning and shaping of fruiting trees should be light, focusing on pruning off long branches, dead branches and diseased branches, leaving more inner branches, and prohibiting shortening of fruiting mother branches. When pruning the canopy, the key side branches are pruned off to ensure balanced fruiting and growth. When pruning, the drooping branches should be retained to promote flowering and fruiting. 1.8.3 It is recommended to use the explicit renewal method to renew the main branches and secondary main branches, remove the old side branches, and accelerate the development of strong shoots. After the new shoots sprout and the shoots are extracted, the buds are wiped in time to control the shoots, and a new crown can be formed in about 2 years, and then the fruiting ability can be gradually restored.
1.9 In order to ensure the overall yield and quality, it is necessary to do a good job of thinning and topping, reduce nutrient consumption, concentrate water and nutrients, improve the quality of flowers and increase fruit setting rate, promote fruit expansion, increase yield and improve efficiency. It is recommended to carry out flower thinning in early March every year, and there are two main methods of flower thinning: one is to thin the flower branches, prune off the hidden leafless flower branches and weak flower branches in the crown when the buds are studied, and leave 2 strong flower spikes for each fruiting mother branch; The second is to thin the flower buds, 10 days after thinning the flower branches, the remaining flower spikes are thinned, each flower spike is removed from the head and tail to leave the middle, and each flower spike leaves 4 full flower buds. Leave 1 2 sturdy flower spikes on leafless branches, prune off dewy flowers, deformed flowers, and weak flowers, and leave 80 100 sturdy flower spikes for each fruiting tree.
1.10 Strengthen the protection of flowers and fruits, if it encounters extreme weather such as high temperature and continuous rainfall, it will affect flowering and fruit set. It is suggested that fruit farmers should speed up the physiological differentiation of tree flower buds by circumcision and root cutting in November. The width of the circumcision process is 0About 2 cm is advisable to avoid damage to the xylem. For pomelo trees that bear fruit in the current year, paclobutrazol can be sprayed in late October, which helps to strengthen the tree, increase the amount and quality of flowers, and reduce fruit cracking. Studies have shown that paclobutrazol spraying can increase yield by 15%.
1.11. Timely bagging of pomelo bagging, white non-toxic, light and breathable film bags should be preferred, so that the surface of pomelo can be evenly colored, and the yield and quality should be improved. The bagged pomelo has a higher sugar content, reduces pesticide residues, and reduces the threat of pests and diseases. It is recommended to bag the pomelo from 9 to 11 a.m. and 15 p.m. to 17 p.m. on sunny days when the diameter of the pomelo reaches 7 8 cm, and it is forbidden to work in rainy days and high temperature periods. Before bagging, the fungicide + acaricide + insecticide mixture can be sprayed once to ensure that there are no insects and bacteria in the bagging, and the bag can be carried 3 days after spraying. After the wind and rain weather, the bagging condition should be checked in time, and if it is found that there is a phenomenon such as falling off, it should be remedied in time to ensure the quality of the bagging. 2 Major pest control measures of pomelo**.
2.1 Huanglongbing, Hongxin pomelo Huanglongbing, also known as yellow blight, after the leaves are damaged, there will be mottled and yellowing symptoms, and the leaves will gradually fall off in the later stage. After the branch is damaged, the new shoots extracted from the diseased branches cannot turn green normally; After the fruit is damaged, it is easy to deform, ripens early, has less juice, thick skin and light taste; After the root system is damaged, it will gradually decay. The incidence of pomelo huanglongbing is highest in the rainy season in spring and summer and during the drought in autumn, and is mainly transmitted by grafting and citrus psyllids. If the pomelo tree is deficient in fertilizer and the water accumulation is severe, it will further increase the incidence. Prevention and control measures: do a good job of seedling quarantine during planting, and prohibit the purchase of seedlings and scion from epidemic areas; Strengthen the management of pomelo orchards, timely top dressing, control the ratio of nitrogen, phosphorus and potassium, increase phosphorus and potassium fertilizer and decomposed organic fertilizer, and reduce nitrogen fertilizer; To meet the water needs of pomelo tree growth; Timely trimming and shaping, maintaining good light and ventilation conditions; Pay attention to the prevention and control of citrus psyllid, can be sprayed orange psyllid control operations, can be sprayed 25% thiazinone wettable powder 1 500 times; When the disease is severe, a hole should be drilled at the base of the trunk, and then 2 5 l of tetracycline hydrochloride should be injected, which can have a good effect.
2.2 Canker diseaseCanker disease is a common disease in the cultivation of red pomelo, after the leaf is damaged, the back of the leaf appears oily spots, which are light yellow, and then turn into light brown round shape, and the leaf lesions gradually ulcerate in the later stage; After the branches are damaged, they will gradually dry up and die, and then there will be leaf and fruit drops. After the fruit is damaged, pale yellow and brown lesions will appear, and the middle part of the patch will be cracked in the shape of a "crater" in the later stage. The germ can survive in the disease for a long time, and then spread with wind and rain, and also with insects. Prevention and control measures: pay attention to the quarantine of seedlings and realize the cultivation of disease-free seedlings; In winter and spring, pruning operations are combined to clean up the dead branches and leaves in the pomelo orchard;
Paying attention to the work of pomelo bud wiping and tip control can reduce the incidence; Timely top dressing, fertilizer control; Pay attention to the prevention and control of leaf miners to avoid carrying and spreading pathogens; After flowering, it can be sprayed with 800 times of 30% copper hydroxide suspension or 1 2 100 times Bordeaux solution or 50% (20% or 45%) 500 times of dysenammonium aqueous solution, sprayed once every 1 week, and sprayed 2 3 times continuously. 2.3 Leaf miner moth is one of the common pests of pomelo, the larvae burrow under the epidermis of young stems and young leaves, forming curved tunnels, and the affected leaves gradually curl up and harden, which is easy to fall off, and the young stems are easy to cause canker disease after being damaged.
From May to September every year, it is the peak period of damage of leaf miners, and if the temperature exceeds 36, the incidence rate decreases. Prevention and control measures: pay attention to the management of pomelo orchards and control summer and autumn shoots; Weeding in time to avoid leaf miner moths from inhabiting here; Pay attention to the use of insecticidal lamps, use the phototaxis characteristics of leaf miners, hang black lights and frequency vibration insecticidal lamps in the pomelo orchard, turn off the lights during the day, and turn on the lights at night, which can have a good booby trapping effect; Clean up the fallen leaves and dead branches in the pomelo orchard in time; Pay attention to the deep turning of the soil in winter to effectively reduce the number of larvae that pupate into the soil; When the number of leaf miners is large, it is recommended to spray 2 500 times of 10% dichlorophenothrin, 500 times of 25% insecticidal aqueous agent, and 1 500 times of 5% imidacloprid emulsifiable concentrate, spraying once every 1 week, and spraying 2 3 times continuously. 2.4 Red spiderRed spider is an important insect pest that endangers the safe production of red pomelo, which will cause great harm to leaves, shoots and fruits. After the leaves are damaged, a large number of gray-white spots will appear, lose their luster, fall off in the later stage, and the tree will be Xin'anjiang; When the fruit is damaged, it will lead to fruit drop. From June to August every year, it is the peak season for red spider mite.
Control measures: improve management awareness, control cultivation time, method and density, and realize the cultivation of robust plants; Pay attention to top dressing, increase the application of phosphorus and potassium fertilizer and decomposed organic fertilizer, and apply less nitrogen fertilizer to improve the insect resistance of plants; Pay attention to the protection and utilization of natural enemies, lacewings, ladybugs, etc. are the natural enemies of red spiders, and they can be released in the pomelo orchard to kill red spiders; Spraying 2° stone sulfur mixture after fruit picking can have a good preventive effect; When the number of pests is large, it is recommended to use dicofol 50 ml + laundry detergent 250 g + zero diesel 100 g + water 50 kg, fully mixed and sprayed under the leaves, which can kill the pests and will not harm the beneficial insects, spray 1 time every 2 3 weeks, and spray 2 3 times continuously. 3 Conclusion To sum up, Sinan County has a long history of pomelo planting, and the local pomelo fruit is large and thin-skinned, crisp and juicy, sweet and sour, and is well received by the market. In the new era, it is necessary to actively promote the application of high-quality and high-yield cultivation technology, master the key points of high-yield cultivation technology of red pomelo, and improve the awareness of pest control, combine the characteristics of major pests and diseases, formulate comprehensive and effective control measures, reduce the incidence of pests and diseases, improve the yield, quality and economic benefits of pomelo, drive fruit farmers to get rid of poverty and become rich, and promote the good development of the pomelo industry in Sinan County.
Green pomelo net seedlings, click to understand