Grapefruit has the scientific name is Citrus grandis (L.) Osbeck, citrus (Rutaceae). Grapefruit also known as cotton, kan how tch’lou (Thai), mak Somo (Laos), kroth thlong (Cambodia).
They grow grapefruit to eat fruit, shade, take flowers to marinate food aroma, fruit cake or for distilled grapefruit aromas perfume cosmetics …
The parts of the plant are used in medicine as grapefruit: grapefruit juice, peel, leaves, flowers, seeds, nut shells.
Grapefruit fruit is useful for people with increased cholesterol, hypertension, atherosclerosis, diabetes, obesity.
Especially, in the white pulp of the fruit of grapefruit contains pectin, essential oil, hesperidin, maringin, are substances that work to reduce cholesterol – blood, protecting the sustainability of capillaries, prevent hypertension and stroke cerebrovascular, myocardial infarction …
Leaves of fresh grapefruit is often used to cook with different kinds of aromatic leaves (tree basil, mint, marjoram, perilla, citronella, wormwood …) for inhalation in treating flu, headaches.
Some basic information for business Pomelo fruit trees
Grapefruit tree is easy to grow when planted from seedlings in the nursery elected, fruit is clean, nutritious. A ha grapefruit takes 5 years old can yield results from 50-65 thousand / year.
1. Demand for eco-tree:
Temperature: grapefruit tree can live and thrive in the temperature range 13 – 38oC, preferably 23 – 29oC. Under the trees stop growing 13oC, below minus 5 ° C, grapefruit will die;
Lighting: grapefruit tree is not suitable for direct sunlight, appropriate light intensity for grapefruit around 10000-15000 lux (equivalent to the light at 8 am and 4-5 pm in the dry season);
Water: grapefruit tree huge demand for water, especially during flowering and fruit development. On the other hand, grapefruit is also very susceptible to flooding conditions. During the rainy season, if high water table in the ground and could not drain, tree roots will rot, yellowing and death.
2. Crop planting grapefruit:
Grapefruit trees are usually planted at the beginning of the irrigation season to help, but also can be grown throughout the year if irrigation water initiative.
3. Planting windbreaks and shade for grapefruit:
Grapefruit appropriate scattered light, so to planting shade trees with other plants grapefruit as soursop, … At the same time, planting windbreaks as coconut, mango, all kinds of timber, … to limit the damage caused by storms and the spread of insects and pathogens.
Here are some breeding techniques, planting and care of basic grapefruit
I. Request BƯỞI Ecology of plants:
1. Temperature: Grapefruit Tree native tropical and subtropical, can grow to be between 40 degrees north latitude to 40 degrees south latitude, the most suitable temperature of 23- 29 ° C.
2. Lighting: Light intensity is appropriate for grapefruit tree 15. 10. 000- 000 lux (equivalent to bright sunlight or sun at 8 pm at 16 hours). In terms of the South, when planting shade trees planted grapefruit should East-West direction.
3. Water: grapefruit trees need lots of water during the period of fruit and seedlings, but also very afraid of waterlogged trees. The most suitable soil moisture is 70 to 80%, between 1000- 2000 mm rainfall / year. In the dry season should be watering grapefruit, but the water is not salty than 3 ‰.
4. Land: Land grapefruit crop cultivation must have thick layer of at least 0, 6m, light mechanical composition or medium, porous, airy, well-drained, with a high organic content> 3% , PH 5, 5- 7, not more than 3 ‰ salinity, groundwater levels under 0.8m.
Soil Preparation II Grapefruit Tree Planting:
At low soil, when planting grapefruit need to dig ditches to discharge to Phil alum, salty and improve farming floor; annually if the flood water garden design of embankments need to protect crops.
1. Planting windbreaks for crops Grapefruit: It should be planted on embankments windshield of a garden with trees such as jackfruit, mango, coconut ….
2. Grapefruit trees Distance: Depending on the breed and the planting soil that distance changes accordingly, may be 5X6m or 6X6m or 6X7m
3. Planting shade: Grapefruit Tree appropriate scattered light, so it should be planted shade trees such as plum, custard, coconut fiber, cau … Trees are often planted shade trees interspersed between 2 grapefruit or along spoon.
4. Varieties planted: Depending on soil, climate and demand that appropriate plant breeding. MD can plant varieties such as green grapefruit, pomelos, grapefruit fruit, grapefruit tea bar.
III. Technical grapefruit seed multiplication:
a) grapefruit grafting method:
Propagation coefficient high, take advantage of the rootstock, good lodging resistant plants, increase longevity, retaining the good properties of grapefruit bullets.
– Grafted grapefruit: It is possible to use the same local sour grapefruit rootstock or used as original orange rootstock secret to a stable way grapefruit seed quality. Rootstock should be planted from fine particles, collected from the good fruit on the trees, collecting seeds from the left chose not fall, fruit diseases. Before the transplant, grapefruit rootstock must be periodically spray insecticides against the pest.
– Eye transplant, stem Tower: Use disease-stored grafts in the grid prevents the pest. Spike took the branches leaning grafts is approximately between themselves, are selected according to the direction and position of the grapefruit trees to reduce the incidence of atypical form, not taking his eyes from the branches landscaped compound (pass) and grapefruit trees grow messed-up On the ground.
b) Methods of twigs grapefruit extract:
Help keep completely the characteristics of grapefruit bullet, shallow roots, planted on suitable land with water level slightly higher level but low propagation coefficient, easy to spread dangerous infectious diseases, plant grapefruit rapidly aging and can not make use of the advantages of the rootstock. Grapefruit easily fallen by poorly developed root system, does not correspond to the development of the grapefruit tree. Notes on twigs grapefruit extract:
– The grapefruit tree extraction tools must be sterilized before and after performing operations on each segment extracted stem.
– Age cuttings should not be too old, just select the branch buds.
– Tree branches must be used to extract grapefruit is in a state of good development and growth, no pests, especially the yellow leaf disease and Tristeza Greening.
c) Standards bullet grapefruit:
Grapefruit tree is the tree line early disease, with clear origins, is in a phase of growth well developed, there is no pest infestation signs, test results negative for dangerous diseases to grapefruit as Greening Gold leaf disease, Tristeza, yielding stable qualities.
2. Criteria for good grapefruit varieties:
– Grapefruit tree seeds must be true, healthy growth, non-germ pests
– Uniform grapefruit tree morphological and genetic characteristics, the difference does not exceed 5%
– The height from the floor of elected grapefruit> 60cm, with 2-3 branches grade I
– Diameter of grapefruit trees grafted surface measuring 10cm elected: 0,8-1cm
– Diameter of grapefruit tree grafting (measured on the grafted wound 2 cm)> 0.7cm
IV Technician Grapefruit Tree Planting And Care:
1. pomelo planting season:
Mekong Delta can be grown year round but grapefruit ensure irrigation and drainage for plants. It is best planted in early rainy season.
2. Prepare the grapefruit crop land size:
MRD should cover to plant tissue is to raise floor purpose farming, land for land surface models are often muddy or dry ditch, size 80 to 100cm in diameter, depending on the height of the high ground, between tissues should dig hole size 0, 6X0, 6m. Then for 20- to 40 kg of manure pits Super Lan + 0 + 1 kg, 5 kg of lime mixed with soil
3. The method set pomelo children:
When planted pomelo put down between tissue, facial tissue placed horizontal elected, install it in the tissues, keep plugging pile dwarfing trees winds, grapefruit trees watered.
If planted with grapefruit transplant grafts should rotate about the main wind direction in order to avoid splitting the bud by the wind. If using cuttings planted grapefruit trees, branches should be placed above the ground, a tilt of about 45 ° to help root branching tree well.
4. The original Cabinet grapefruit moisturizing:
In the dry season should mulching with straw or hay to keep moisture, while also suppressing weeds. Note the cabinet to leave the stump about 20cm to limit the types of fungal attack grapefruit tree.
5. Irrigation and drainage for grapefruit:
Grapefruit trees need water during periods of seedlings and fruit trees bloom, but the plant is very afraid of flooding, it is necessary to pay attention to drainage during the rainy season grapefruit.
6. Phil dredger compensation for grapefruit:
Phil mud on job training for grapefruit can be combined with drought to create plants blossom; can pay around 2- 3 calendar months or after the rainy season, approximately 2- 3 cm thick layer of mud is best. Time to pay compensation mud once every 2 years.
7. Fertilizing for grapefruit:
Depending on the soil type, variety and growing conditions of grapefruit trees that provide for appropriate fertilizers.
a- basic construction period of grapefruit:
Phase grapefruit from 1- 3 years old, fertilizers are divided into 3 to 5 times per year for top dressing; 6 months after planting can use mixed 40 gr urea water to irrigate 1 month / times. Dose of fertilizer basic construction period grapefruit
Save y`: Can be used in accordance with the fertilizers Komix as:
Basal for grapefruit: 1. 2kg organophosphate Komix microbiology / root.
Dressing for grapefruit: Komix powder fertilizer used exclusively for fruit: For stable fruit pomelo, every year can be divided into 3 times fertilizer, fertilizer each time 0, 5- 1kg / plant / time.
b- trading period grapefruit:
– After harvesting 1 week, fertilizers: Urea 25% + 25% + 5 20kg Lan organic fertilizer / root / year.
– 1 month before flowering grapefruit tree fertilizer: Urea 25% + 50% + 30% potassium Lan.
– After pomelo fruit (fruit growing stage) fertilizers: Urea 50% + 25% + 50% potassium Lan.
– A month before harvesting the fruit pomelo, 20% potassium fertilizer.
Phase grapefruit growing, amount of fertilizer should be divided doses depending on the severity of legumes and the development of pomelo fruit. Every year the additional fertilizer 0, 5- 1kg feces Ca (NO3) 2 / the portion to improve the quality and shelf life after harvest of grapefruit
In addition to the inorganic fertilizers on, to create organic products meet export demand for fruit, grapefruit when fertilizing should use compost or use of organic fertilizers such biochemical Komix to fertilize grapefruit, with fertilizers and dosages are as follows:
* Business period grapefruit trees: Fertilizing Komix powder used for fruit trees doses 6kg / year plant, fertilizer 3 times:
– After harvesting fruits grapefruit fertilizer 2kg / tree.
– Before flowering grapefruit fertilizer 2kg / tree.
– When pomelo fruit farming fertilizer 2kg / tree
Also during grapefruit growing foliar spray Komix Komix superzinc- k FT and about 5 times / season left, each separated by 10 days the dosage instructions on the packaging.
8 – Pruning Canopy grapefruit:
a – Pruning grapefruit:
Every year, after harvesting the fruit pomelo, need to remove the spike has brought the left (usually very short-range 10- 15cm) diseased branches, weak branches, twigs inside pomelo trees can not afford to bring the left , the branches are crossed, and also to remove the branches exceeded during carrying fruit to restrict competition for nutrients and pests grapefruit trees. Note: during the cutting process must disinfect water or alcohol javel 90 ° before the sniper scene grapefruit trees.
b- Create grapefruit tree canopy:
From grafts or more locations around 50- 80cm, then press the left top scene grapefruit, for the purpose of sleep and sprouts sprouts grow inside. Choose healthy 3 sprouts, straight main stem and grow in 3 directions relatively uniform as the primary branches 1. Plug bamboo poles used to hold the branches to the ground level 1 grapefruit created with the original main body 1 35- 40 °. From developing branch branch level 1 level 2 share lead retain 2- and 3 branches. 2 level to spike to a main trunk and branches 15- 30cm 20- 25cm this way the other branches, along with branches forming a Tier 1 original 30- 35 °. Grade 2 from branch will form three primary branches, branches are not limited in number and length, but is necessary to remove the seat grapefruit tree grows too thick or too weak. After 2 years will have the canopy grapefruit balanced, convenient care, disease prevention and pomelo fruit harvest.
9. Handle for grapefruit trees bloom:
Flowering grapefruit tree needs time to dry the flower, so in the management of the water garden can produce grapefruit drought to bloom simultaneously.
Create a 12- month drought in 01 calendar, Tet Trung Thu harvested (7- 8 cases against about a calendar month); or create 3- 4 months of drought in the harvest calendar to Lunar New Year (12 months period for the calendar upon). During the rainy season, use nylon fabric coated grapefruit tree or around the Philippines to cover drought for flowering grapefruit tree.
* Option 1: After grapefruit tree was fertilized 2nd, to calendar 15/3 (20 days), then start watering again 2- 3 times a day and 3-day watering constantly, to irrigate every 4th day days. 7- 15 days after the first round watering grapefruit trees will bloom (this time watering days holidays) 10- 15 days after flowering will pomelo fruit falling petals.
* Option 2: After grapefruit tree was fertilized 2nd calendar 15/3 Phil VBA to be soaked with water, may award a thin layer of mud 2- 3 cm. After 20 to 25 days if there are waiting for compensation mud cracked dry mud of irrigation return the same way 1.
10- pomelo fruit Neo:
By the time of harvesting grapefruit can lower the prices on pomelo fruits from 15 to 30 days to wait for prices using urea or fertilizer ingredient leaf in the hormones of heading Auxin, gibberellin spray left straight up on grapefruit.
V. – Grapefruit Tree pests and control measures Tri:
1 – pomelo citrus psyllid damage:
Harmful: the yellowing disease agent on Citrus Greening, causing severe damage in the Mekong Delta. Both the insect larvae and are sucking grapefruit trees bud and transmission.
– Prevention and treatment measures:
+ Raising the ants and the conservation of natural predators to control pests in the garden planting density of grapefruit.
+ When planting a garden design should grapefruit crop protection barrier to wind, to prevent pests from entering the garden.
+ Use of chemicals to spray at bud grapefruit with drugs such as Applaud- Bas, Butyl, Bascide, fenbis, SecSaigon …
2 – leafminer damage grapefruit:
– Cause two: Attack at the young leaves of grapefruit trees, borers under the leaf epidermis as zigzag lines deformed leaves, zigzag, affect the development of the grapefruit tree bud. Also leafminer also causes ulcers easy to penetrate.
– Prevention and treatment measures:
+ Care for grapefruit trees grow well, pruning simultaneously for focused bud stage, rapid maturation.
+ Use of chemical drugs such as fenbis, Lancer, Diaphos, vibasu, Supracide …
3 – Aphids damage grapefruit:
– Harmful: chit often sap in bud grapefruit, affect the growth and development of shoots, hoppers discharging extra biliary facilitate development of sooty fungus. Aphids are also vectors on citrus Tristeza as grapefruit.
– Prevention and treatment measures:
+ Raising the ants to control the density of aphids in the garden of grapefruit trees.
+ Spray grapefruit tree at the bud when aphids appear in categories such as: Lancer, SecSaigon, Vibasu, Pyrinex, D- C Tronplus oil …
4 – Spider grapefruit tree damage:
Both the insect larvae are small, brown, pale yellow or white depending on type, wingless, with eight legs like spiders.
– Harmful: Full insect larvae and the young leaves and sucking often outside the small crust of about 1- 2 months old, the everlasting appeal of spiders rarely make fruit fall, but often peel skin was rough as bran , reducing the commercial value of pomelo fruit.
– Measures to prevent harmful spiders grapefruit treatment:
+ In nature there are many predators can reduce mite populations.
+ May apply measures to limit farming left by sucking spider bag left at a young age
+ Spray the plant protection when needed: Comite, sulox, Ortus, D- C Tronplus oil …
5 – root rot melting on grapefruit:
– Symptoms: At first make bark disease in the root zone swollen grapefruit water, brown rot into the Real format, then dried, cracked down, melt the dark brown very smelly …
– Agent: caused by Phytophthora sp.
– Harmful: grapefruit tree at root diseases, stem rot shell especially in non-law; on itself when cracked shells made of plastic flowed very foul smell; on the leaves, causing leaves yellow and fall off; on the contrary makes fruit left to rot especially those near the ground. The disease usually attacks in the pomelo gardens with high density, high humidity.
– Prevention and treatment measures:
+ Planting grapefruit with moderate distances to reduce moisture in the garden.
+ Model pomelo planting tall must not be submerged.
+ Annually grapefruit fertilizer per tree from 20 to 30 kg manure.
+ Spray the drug categories as: Mexyl- MZ, Alpine, Ridomyl, Aliette, Vimonyl, Ridozeb …
6 – ulcer disease caused grapefruit:
– Symptoms: The disease can damage the leaves, fruit and twigs grapefruit, development contagious during the rainy season and when there is fog, the most visible symptoms on leaves, burned the circular spots around the areola pomelo leaves yellow but not deformed.
– Agent: Because the bacterium Xanthomonas pv campestric. citri cause for grapefruit.
– Harmful: on the leaves and fruit of grapefruit, small lesions initially, favor dark green water, then turns into light brown humps grow leaves or peel pomelo leaves do make the reduced photosynthetic capacity and left goes mushy rot. The disease spreads rapidly
Through irrigation, rain and fog, causing heavy damage in the pomelo gardens is leafminer attack and on the grapefruit seed nursery.
– Prevention and treatment measures:
+ Cut and disposal of branches, leaves, fruits grapefruit illness, strict hygiene including farmers gardening clothes.
+ To minimize the damage done drying the leaves and fruit of grapefruit, especially leafminer treatment room.
+ Spray the plant protection drugs for grapefruit as: Kasuran, Funguran, Bordeaux, Coc …
7 – yellowing disease caused grapefruit Greening:
– Symptoms: The leaves are still green but grapefruit yellow spots, while in some leaf yellowing leaf blade leaf veins remain green, small leaves and narrow long as rabbit ears, deciduous. On grapefruit, small branches left sick, twisted, black thui grain, cotton many times in the same grapefruit.
– Agent: Due to gram-negative bacteria (Liberibacter asiaticus) cause against the pest and disease due to grapefruit,
– Measures to prevent:
+ Planting disease-free grapefruit.
+ No propagation from infected grapefruit trees.
+ Planting windbreaks to prevent pests from other places for garden planting grapefruit
+ Sterilize pruning knife when grapefruit.
+ Spray the insecticide hoppers such as Applaud- Bas, Butyl, Bascide, fenbis, SecSaigon …
8 – Scabies on grapefruit:
– Symptoms: Lesions have emerged pale brown on the underside of leaves, on shoots and fruit, no pants yellow scab around like ulcers.
– Agent: Elsinoc fawcetii fungal cause for grapefruit.
– Harmful: Mushrooms are often attacked on the bud, shoots and fruit pomelo, foliar leaf fungus attacks the underside of leaves makes grapefruit was grainy, distorted, reduced photosynthetic capacity, reduced commercial value Is the left. Disease development and spread dramatically in the last rainy season and water.
– Prevention and treatment measures:
+ Clean the garden, pruning and destruction even the branches, leaves, fruits grapefruit sick.
+ Injection of drugs such as Zin, Dipomat, COC, copper oxychloride, Funguran, Dithan- M …
Grapefruit Harvest VI:
1. The time for harvesting the fruit of pomelo:
Grapefruit trees from flowering to harvest about 6- 7 months depending on breed, age of trees, growth status … should be harvested in the cool weather, not to harvest after rain or fog.
2. The method of harvesting the fruit of pomelo:
Use a knife to cut stems and grapefruit, clean them and put in baskets to a cool place, classification.
3. Handling grapefruit harvest:
– Can spray 10-40ppm 2.4 D levels to prevent dryness and loss grapefruit stubs.
– Spray thiabendazole 40% dilution at a concentration 500 times at the time of 1-2 weeks before harvest, or soak for 3 minutes when the new harvest grapefruit.
– Spray Iminoctodine diluted 2,000 times 25% at 4 days before harvest or soak for 3 minutes when the new harvest fruit grapefruit to reduce damage rate.
4. Preservation of grapefruit:
After harvesting, or handling chemicals, keep a few days left in the shade to dry before storing it in your pocket. Bags should be thick around 0,02-0,03mm, each bag should only keep one left. If stored for long periods should use very thin PE sheath wrapped.