There are many diseases of grapefruit, how to prevent them?

Scale insects mainly absorb plant juice and cause poor plant growth and leaf and fruit dropping. The prevention and control can be used with 1000 times of cocoon kill, 1000 times of water ammoniathion, 700 times of malathion, 1000 times of 20% diaformamidine, and pomelo canker disease is mainly harmful to pomelo tree shoots and immature fruits, affecting yield and quality, and reducing economic value. It is a bacterial disease that is mainly transmitted by wind, rain, and insects, and is most likely to be epidemic after heavy winds.

The lesions are yellow-brown, and in the process of planting pomelo, we adhere to the guiding ideology of "prevention and control, comprehensive prevention and control" and the reasons for early treatment, small treatment and treatment. Spray once a month, grapefruit has no obvious pests and diseases, find pests and diseases in time, small secret recipe: add mineral oil, vegetable oil (green peel orange oil, boosters, etc.) when fighting pests and diseases can greatly increase the control effect.

Pruning reasonably, winter stone sulfur mixture clear garden, brush white, spring hanging predator mites to control red and yellow spiders, spring and summer each plant to hang a yellow board blue board, an average of four acres of land a black light, we advocate green ecology recommended to try not to use pesticides throughout the year.

It is necessary to prescribe the right medicine, and the main grapefruit needs to be prevented and treated at the stage of growing young fruits: mainly macular disease, scab disease, sand skin disease, bituminous coal disease, canker disease, red spider, scale shell, longhorn beetle, etc. During the peak period from April to May, you can spray 2000 times of pyridazinone once, or 2500 times of Tiansaoli Spray 3000 times of liquid Grammante in each month, and 1500 times of Liquid Gramfull in November, which are mainly extremely effective for red spiders.

The horned shoulder bug is also called the big green bug, which mainly harms pomelo and citrus in Sha Tin, but also harms apples and pears. The main damage is to suck the juice in the peel of the pomelo in Sha Tin, so that the peel becomes hard and tight, and the slightly smaller fruit falls directly, and the horned shoulder insect occurs in one generation every year, and the adult overwinters in the dense branches or cracks, and the adults begin to move and lay eggs in the young fruit stage from April to May of the following year, and the nymphs bloom from June to August, and the damage is the most serious.

When planting grapefruit, you can apply some fertilizer or spray some pesticides around the grapefruit tree, and you can also sprinkle some insecticides, so that the insects can stay away from the grapefruit tree, and you can achieve disease control.

Choose pesticides suitable for virus prevention spraying, and at the same time, you should pay attention to the management skills of grapefruit, but also pay attention to the lighting problems of pomelo trees, and also pay attention to viruses in the soil.

If there are many diseases and the types are more complex, in fact, you can also directly use relevant chemical reagents, and there are many reagents that can solve many diseases.

The grapefruit tree is a disease of white spot disease, you have to find an agricultural expert quickly**, otherwise there will be no fruit next year.

Caused by insect infestation. Blowing Miansuke. Scale insects.

When it comes to plant diseases, I believe everyone is familiar with them, as long as they are plants, they are prone to diseases in the process of growth. The parts of plants that produce diseases include branches, leaves, and fruits, so what are the symptoms of various diseases of grapefruit leaves? Next, Baibai Safety Net will explain it to you.

1. Grapefruit scab disease.

Symptoms of harm. It is mainly harmful to the young leaves, flowers and young fruits of spring, late autumn and winter shoots. When the disease is severe, it causes a large number of fallen leaves, fallen flowers and fruits, and the damaged fruits are deformed, the quality deteriorates, and the commodity grade is low. At the beginning, the affected leaves appear with small round spots in the form of water stains, and then turn waxy yellow.

The lesions expand with the growth of the leaves, and gradually become corked, and the leaves bulge to one side of the leaf to form a cone-shaped scab, and the other side is concave inward, and the leaves with many lesions are twisted and deformed, which seriously causes defoliation.

2. Grapefruit anthracnose.

Symptoms of harm. Grapefruit anthracnose can damage leaves, shoots, and fruits. The leaves and branches are in a rainy and humid climate, and the leaf tips are pale cyan with dark brown patches, such as boiling water, and the margins are not significant; The tender shoots are scalded in boiling water and acutely withered.

In short, humid climates that soon become clear, it is manifested as chronic symptoms: leaf spots round or amorphous, marginal dark brown, slightly arched, grayish-brown to grayish-white in the middle, often whorled on the spot;

3. Grapefruit macular disease.

Symptoms of harm. Grapefruit yellow spot disease, the affected plant produces dozens or hundreds of spots on a single leaf, which hinders photosynthesis, weakens the tree, and causes a large number of fruit drops.

Symptoms of leaf damage: The leaves of the grapefruit tree are harmed by yellow spot disease, and one or several oil-soaked small yellow spots are born on the back of the leaves at the beginning, and the lesions will gradually turn into yellow-brown patches as the leaves grow. Or produce russet slightly convex small lesions on the leaf surface, then slightly expanded, slightly concave in the middle, become gray-brown round to oval spots, and the later disease part ** becomes gray-white, causing a large number of defoliation when the disease is serious.

Fourth, grapefruit bituminous coal disease.

Symptoms of harm. In the early stage of soot disease, a layer of dark brown mold is produced on the surface of leaves, branches or fruits, and then gradually develops into a black velvety mold layer covering the diseased part, and the mold only grows on the surface, which is soot-like and cannot invade the tissues of pomelo trees.

This is called macular disease. Macular disease is a fungal disease, which is very common on grapefruit leaves, and when the disease is severe, the pomelo leaves will fall in large areas.

Lack of some, Huawei, specifically, is the lack of some reasons, generally speaking, the yellowing of the leaves should be a lack of potassium elements, hey, it seems to be this element, I don't remember it very clearly, you can find out what element is missing in the yellowing of the leaves, and then the corresponding phone fee of the division also has the fertilizer of this element.

This grapefruit leaf should be a charcoal disease.

It can be sprayed with 65% mancozeb or 70% mancozeb wettable powder 500 times, once every 10 to 12 days, and 2 to 3 times for treatment.

Grapefruit is a citrus plant in the family Rutaceae.

Grapefruit, is an arbor. The young branches, leaf back, peduncle, calyx and ovary are pubescent, and the young leaves are usually dark purplish-red, and the young branches are flat and ridged. The leaves are thick, dark green, broadly ovate or elliptic, 9 to 16 cm long, 4 to 8 cm wide, or larger, obtuse or rounded at the apex, sometimes short and pointed, rounded at the base, wing lobes 2 to 4 cm long and 3 cm wide, and the wing lobes of some species are very narrow.

racemes, sometimes with axillary solitary flowers; Flower buds pale purplish-red, sparsely milky-white; calyx irregularly 5 to 3 shallowly lobed; petals up to 2 cm long; stamens 25 to 35, sometimes partially sterile; The columella is thick and long, and the stigma is slightly larger than the ovary. Fruit spherical, oblate, pear-shaped or broadly conical, usually more than 10 cm in diameter, pale yellow or yellowish-green, hybrids vermilion, very thick or thin peel, spongy, large oil cells, convex, fruit core firm but soft, scoop sac 10 to 15 or as many as 19 petals, juice cell white, pink or bright red, rarely creamy yellow; There are more than 200 seeds, there are also seedless, irregular shape, usually approximately rectangular, the upper part is thin and often truncated, the lower part is full, and most of them are underdeveloped, there are obvious longitudinal ribs, cotyledons are milky white, and the embryo is single. The flowering period is from April to May, and the fruiting period is from September to December.

The leaves, flowers and peel of pomelo contain roughly the same aromatic oils as citron and lemon. High-quality pectin can be extracted from the peel, and the pulp can be processed into juice, fruit wine, citric acid, jam and canned food. The economic benefits of the fruit are expected to increase by 4 times after the comprehensive utilization of the fruit, and there is still great potential for the comprehensive utilization of pomelo.

The pomelo is as big as a gourd, sweet and juicy. The peel is orange-yellow, aromatic; The flesh is tender and juicy, the edible part of the fruit is 45 to 65, the juice content is 53, the pulp contains 7 to 12 total sugars (there are certain differences between varieties), the acid content is to, the soluble solids are 10 to 45 mg, and the edible part contains 34 to 45 mg of vitamin C, and contains vitamins B1, B2, carotene and other vitamins and a variety of minerals. Because of its high sugar content, moderate sweetness and sourness, rich nutrition, and durable storage, pomelo is known as "natural canned".

The pulp is high in vitamin C. It has the effect of eliminating food.

The leaves of this plant have been damaged by an overdose of pesticides.

Summary. Stone sulfur mixture is a commonly used bactericide and insecticide, which can control powdery mildew, rust, brown rot, brown spot, scab, red spider, scale insect and other pests and diseases.

What kind of disease does the grapefruit tree I planted have, and how can I prevent it?

Hello, I am inquiring for you here, please wait a while, I will reply to you immediately Hello, is there **

It is said to be leaf spot.

What kind of medicine is used to prevent and treat it?

Stone sulfur mixture. Stone sulfur mixture is a commonly used bactericidal and insecticidal agent, which can prevent and control powdery mildew, rust, brown rot, brown spot, scab, red spider, scale insect and other pests and diseases.

The dosage of stone sulfur mixture: when using stone sulfur mixture, some water should be added to Liangye Cave for dilution, and the formula of water addition of spine reputation: water addition = concentration of the original solution Target concentration - 1.

Do you buy something on JD.com?

Pesticides should not be available, you should go to your local pesticide store to buy them.

Good! We may not have bought it here. I'm from Shaoxing.

The grapefruit tree is a plant that can tolerate both heat and drought, and the temperature suitable for planting grapefruit trees is 15-20, which is the best temperature for the growth of grapefruit trees.

Anthrax is a common disease in pomelo orchards in Sha Tin. There are two types: chronic and acute, with the chronic type being the most common. Chronic anthrax mainly causes leaf spots, and there are small black particles on the lesions that are slightly convex and arranged in the shape of concentric rings, which affects the photosynthesis of leaves.

<> plus orchard fertilizer and water management Increase organic fertilizer and phosphorus and potassium fertilizer to fruit trees, do not apply nitrogen fertilizer Do a good job of orchard drainage in the rainy season In early winter, fruit trees should be frozen in advance, and the link of pesticide damage is the use of pesticides for spraying, seed dressing, soaking, soil treatment, etc.;

There are two main types of pesticide damage, namely acute drug damage and chronic drug damage. If symptoms appear within a few hours to a few days after application, it is called acute drug damage; After pesticide application, the symptoms appear later, and the comprehensive prevention and control method prunes frequently to ensure that the tree body is ventilated and transmitted, and the diseased fruits, branches and leaves are removed in time to reduce the source of disease; Pay attention to drainage, apply thin organic fertilizer frequently, and enhance the resistance of trees and fruits; Young leaf and young fruit stage, and the month before fruit picking.

Scientifically build a garden to prevent anthracnose parasitic plant communities from mixing and matching in one ecosystem, and eliminate the living environment of anthracnose from the source; The same inch must be built in a place with a large drop and good drainage, and the soil is best selected with ventilation and loose sandy soil.

Once the temperature exceeds 30, it is not conducive to the transplanting of grapefruit trees, so it is best not to plant grapefruit trees at a temperature of 30 degrees and pay attention to the planting time of grapefruit. The resistance of pomelo is strong, so the planting area of pomelo in China is relatively extensive, mainly concentrated in the area south of the Yangtze River, such as Hunan, Guangxi, Fujian, Yunnan, Guizhou and other places, the planting of pomelo needs to pay attention to time, which can improve the survival rate of pomelo.

Pomelo planting pomelo seedlings directly dig a pit in the ground to plant pomelo seedlings in the afternoon, timely fertilization, and prevent pomelo from bad fruit when planting pomelo.

Pomelo needs to be pruned when planting, especially tall branches need to be pruned off, and it should also be ensured that each pomelo can receive sunlight, and at the same time, you should also pay attention to the flowering time, you can add fertilizer and water more when it is flowering, so as to prevent bad fruits.

The pomelo should be planted in a place where the sun and soil are very good, the soil must be fertile and loose, and the pomelo tree should be watered and fertilized more at ordinary times, and the branches and leaves of the grapefruit tree should be pruned so that it can grow better.

To grasp the time of planting, to timely top dressing, to pay attention to the density of planting, but also to timely sprinkle pesticides, but also to timely top dressing. It is necessary to pay attention to field management, and also choose good varieties of pomelo for planting, and at the same time, it is also necessary to take regular precautions.

During the growth of the grapefruit tree, the leaves are curled, which may be due to viral disease or anthracnose. If the pomelo tree is diseased, it is necessary to cut off the diseased leaves of the pomelo tree and burn them intensively to avoid the spread of the disease. After pruning the diseased wheel leaves, the grapefruit tree can be sprayed with drugs such as carbendazim, methyl tobuzin, zeczeb or chlorothalonil to remove the disease.

The leaves of the grapefruit tree rolled up what medicine.

The curling leaves of the grapefruit tree may also be caused by insect infestation, and in severe cases, the leaves may turn yellow, wilt or fall off. If there are insect pests on the grapefruit tree, such as red spiders or scale insects, it is necessary to cut off the insect leaves in time and burn them intensively. After pruning the insect leaves, the pomelo tree can be sprayed with agents such as dimethoate, worm forest or pyrethrin.

The leaves of the grapefruit tree rolled up what medicine.

The curled or yellowing of the leaves of the grapefruit tree during growth may also be caused by improper maintenance. During the maintenance period, insufficient water or lack of fertilizer can cause the leaves of the grapefruit tree to turn yellow. If it is caused by insufficient water or fertilizer, it needs to be watered appropriately, and a compound fertilizer containing nitrogen, phosphorus and potassium should be applied to the grapefruit tree to make it grow normally.

The leaves of the grapefruit tree with the letter roll up what medicine to fight.

During the maintenance period, in order to avoid pests and diseases in the pomelo tree, proper watering and fertilization are required. Reasonable maintenance methods are conducive to the growth of pomelo trees and can enhance the disease resistance of pomelo trees. During the maintenance period, you can regularly spray fungicides on pomelo trees, generally 20 to 30 days can be sprayed once a time, which can prevent pests and diseases.