(1) breeding method
1, seed propagation and seedling raising
Mature fruits should be collected, peeled, seeds collected, pectin washed, placed in a cool place and covered with sand T.
Before sowing, choose a place with flat terrain, fertile and loose soil and good water source conditions to set up a nursery, turn it deep, apply base fertilizer, turn it into the soil, break the soil and rake it flat to make a border with a width of 1~ 1.2m and a ditch width of 30~40cm, and sow it in February ~ March in spring. Sowing, drilling or on demand. When sowing, sift the sand-stored seeds, select full seeds without pests and diseases, soak them in 0. 1% potassium permanganate for 0 10 minute, wash them with clear water, then seed them with plant ash, sow them evenly, cover them with sand weir soil, and cover them with grass. Keep the soil moist and water it in time according to the weather. Emerge half a month after sowing, and when the emergence reaches two thirds, remove part of the straw cover. Fertilization at seedling stage, talk first and then concentrate, once every 15~20 days after emergence, and once every1~ February thereafter. Combine weeding, thinning seedlings, removing weak seedlings and raising strong seedlings. In Sichuan and Guangdong, acid interplanting seedlings are often used as pomelo rootstocks, and grafting methods include cutting and grafting. Please refer to Sweet Orange for the management of grafted seedlings. Fixed seeds can be produced when the height of grafted seedlings is about 0.75~ 1m and the root-neck machine is greater than 1~2cm.
Step 2: Stratification
Grapefruit is mostly squeezed by air. In Sichuan, it is mostly carried out before and after the rain festival (February 19) and before the sap flows. Guangxi, Fujian and other places, due to the drought in autumn and winter, strong sunshine, can be appropriately advanced. Layering: selecting 3-4-year-old upright branches in the middle and upper part of the crown of excellent mother trees, cutting the trunk diameter above 1/2, then splitting vertically upwards, the length of which is slightly shorter than layering (bamboo slips or plastic paint film), or peeling into rings, then putting them in an autoclave filled with loose broken soil and kept moist, and cutting off the heel in autumn of that year to cultivate for one year.
(2) Planting
There are many kinds of grapefruit in the open space in front of and behind the house. Select shady slope or middle shady slope for pumping. In places with deep soil, planting holes with a width of 1m and a depth of 1.5m are adopted, and each hole is filled with sufficient base fertilizer, 59 kg of organic fertilizer and 0.5 ~ 1 kg of calcium superphosphate. Planting in February and March in spring or autumn, with row spacing of 7x5m or 6x5m, with 0/9-22 plants per mu/kloc. When planting, the root neck of the plant is flush with the ground, and the root system is not in direct contact with the thick base fertilizer.
(3) Site management
Young trees can be intercropped with green manure crops, ploughed in August, or intercropped with food and vegetables. Pay attention to leave a tree tray and cover it with grass in high temperature season to keep the soil moist and loose. Love often breeds weeds. Results the orchard should be cultivated once a year with a depth of 15 ~ 20 cm. Weeding in intertillage 2~3 times a year to eliminate weeds and pests; Fertilizing once in February-March, mainly human and animal manure, is called germination accelerating fertilizer, and fertilizing again in May, mainly nitrogen fertilizer, plays an important role in strengthening fruit; fertilizing and irrigation in August-September has a significant effect on strengthening fruit, mainly human and animal manure, and increasing the application of phosphorus and potassium fertilizer.
Trees can be pruned at 50~70cm, and then 3 ~ 4 branches are reserved as main branches, and the distance between main cores is 3~6cm. If the trunk branches of young trees are too long, they should be picked or cut short. 1~2 years after planting, all flower chisels should be drained to promote the selection of new shoots, and pruning should be carried out by light cutting, draining, cutting off fine branches or appropriately cutting off long branches. Pruning of fruit trees is generally carried out after fruit picking and before spring shoots begin. As a result, the mother branches are mostly leafless, weak and drooping. When pruning, attention should be paid to loosening the dense branches at the top and periphery, and cutting the branches that grow vigorously in summer and autumn to make the crown ventilated and transparent, so as to facilitate the rapid growth and development of fruiting branches in the crown. Other pruning methods are similar to ordinary citrus withering.
(4) Pests and diseases and their control
1, Huanglong disease
Most of them occur in South China, and the infection is lighter than other citrus. Huanglongbing is an infectious disease caused by virus, which can be spread by insects such as withered aphids. Prevention and control methods, strengthen the self-management of epidemic areas, cultivate backup trees, strengthen the prevention and control of pests and diseases, and dig out diseased plants immediately. If most seriously ill interplanting is infected, other crops can be controlled or replanted, and it is forbidden to introduce vaccine with bacteria and establish disease-free nursery.
2. Foot rot
This is a root and neck disease, the pathogen is fungi, which originated from cortex and rotted brown. Pomelo is the least damaged citrus, and the main external causes are high temperature and rain, heavy soil, poor drainage and root and neck trauma. Prevention and control methods: scrape off, scrape off the diseased spots with a knife, and apply 1: 1: 10 Bedouin pulp; Prevention and control of longicorn beetles and brown beetles in time: intertillage weeding, without damaging roots and bark.
3, mites
There are mainly citrus red spiders and citrus yellow spiders. Adults and nymphs harm leaves, shoots and young fruits. When bitter leaves are severe, yellow spiders will leave a lot of leaves, flowers and fruits. The control method refers to the control method related to the sweet shuttle, and also uses the natural enemies of the mountain black arc and the six-point thrips to control the red spider.
4. scale insects
① Blow-net series: Bituminous coal disease can be induced by using nymphs and carving insects to harm trunks, branches and leaves. Prevention and control methods; Biological control of Australian ladybug and scarlet fever in summer and autumn; Or spraying turpentine mixture 0/0 ~15 times in winter and 0/5 ~ 25 times in summer; Or 50 times of cotton oil soap; Or 1000~- 1500 times of 40% dimethoate emulsion or 1000 times of 50% Malavan drunk emulsion. Net transportation: it harms branches, leaves and fruits, and can also induce bituminous coal disease. Prevention and control methods: cut off insect branches and dead branches; Use the sky scattered like wax scales to jump bees: chemical control mostly uses 0.5 baume stone sulfur mixture 10% dimethoate 1000 times solution.
5. Cerambycidae
There are mainly Monochamus alternatus and Monochamus alternatus, the trunk and lateral branches of their frog sacs, and the control methods; Kill adults from mid-May to mid-June, and cut off eggs and larvae in time when they are found in cracks and wounds in bark; Inject 40% dimethoate stock solution and 80% dichlorvos stock solution into the cavity with steel fungus tea or syringe, and seal the larvae with soil. Other pests include litchi and stinkbug. Please refer to the relevant section of Sweet Orange.
(5) harvesting and processing
The leaves, young branches, flowers and skins of Phoebe bournei all contain essential oils. The harvesting of branches and leaves is mainly to collect fresh branches and leaves in the annual pruning season and extract oil by steam distillation. Flowers are mainly harvested naturally, or artificially in bud stage. Due to the different raw materials used, the processing methods are also different. The soon-to-open flower buds can be used as raw materials for extraction, or they can be mixed and harvested to extract oil by steam distillation. The picking period is usually from the end of August to 10, and the cold-pressed oil is mainly processed by using the same-picked drunk peel with a screw oil press. For processing method, refer to relevant parts of red orange.