What to do about oleander leaf worms? control of diseases and insect pests of oleander / 2 insect pests and 4 diseases

It is a modern trend to raise plants indoors, but there is a kind of plant that we must keep carefully, even if oleander, a poisonous plant with strong ornamental quality. It is precisely because of the poison, many flower friends raise very carelessly, thus attracting diseases and insect pests, what about the oleander leaf worms? The following is the pest control of oleander. If you love flowers, you must have a look at them.

First, oleander leaves grow insects, spray and kill with medicine.

Oleander is a highly ornamental plant, but if it is not raised according to the breeding method of oleander, it will grow insects and get sick. Flower friends must be very worried! With regard to what to do about oleander worms, we should determine which kind of bug it is, and then solve the problem. Oleander pest control, we talk about pests and diseases respectively.

(1) oleander pests, aphids / wax mealy scale

1. Aphids

One of the main plant pests, it is also harmful to the health of oleander. It is understood that aphids generally gather on the twigs and leaves of oleander and suck up juice. Symptoms of damage: rigid leaves, small flowers after flowering, or abnormal flowering.

Control methods: when there are few aphids, you can use toothpicks to kill them; when there are many aphids, you should spray 10% imidacloprid ultra-fine wettable powder 3000-5000 times, or fish rattan essence 1000-2000 times.

2. Wax powder scale

In addition to aphids, wax powder scale is also one of the pests of oleander, it mainly gathers in the young leaves, leaf axils and leaf base of oleander, sucking juice. Symptoms of damage: twisted branches and leaves, wrinkled leaves.

Control method: when the insect is in a small amount, the insect can be clipped out and killed with tweezers; when the wax powder scale is serious, it can be sprayed with 1500 times of omethoate EC or 80 times of parasite or 1000 times of 1.2% nicotine EC.

(2) Diseases and insect pests of oleander, 3 diseases

With regard to oleander leaf worms, I believe you know how to deal with them after reading the above contents. However, in addition to being attacked by insects, the disease also harms oleander all the time. It is understood that there are three main diseases of oleander: Brown spot, witches' broom and black spot. The specific symptoms and control methods are as follows:

1. Brown spot

Brown spot, one of the main diseases of oleander, invades from the leaf tip and leaf edge of oleander. Symptoms: oleander leaves produce purplish red spots, and then gradually expand into round, semicircular or irregular patches with raised wheel patterns.

Prevention and treatment: when the above symptoms are found, you can spray 40% polysulfide suspension 600 times, or 30% copper oxychloride 500 times 800 times, or 50% carbendazim wettable powder 800 times 1000 times, every 10 days or so, a total of 2 times 3 times, if possible, you can take turns spraying to prevent drug resistance.

2. Arbuscular disease

One of the main diseases of oleander, it mainly harms twigs. Symptoms: the base of the diseased branchlets is swollen, showing a reddish color, and clusters are often formed, which may even lead to plant death.

Methods of prevention and treatment: when the above symptoms are found, they should be cut off and destroyed in time; at the initial stage of the disease, tetracycline and other antibiotics can be used for prevention and treatment.

3. Black spot

There is one of the diseases and insect pests of oleander, which mainly harms the leaves of the plant. Symptoms: the leaves appear disease spot, and connected into a corrugated, disease spot gray-white or grayish brown; in the later stage, the disease spot will produce black powdery mildew layer.

Prevention and treatment: when the above symptoms are found, 50% carbendazim 500 times or methyl topiramate 600 times can be sprayed, and there will be a good effect after several times.

With regard to the prevention and control of diseases and insect pests of oleander, the editor has introduced this. I believe that when we encounter the above-mentioned diseases in the future, we should know how to do it! Generally speaking, in the process of oleander growth, diseases and insect pests are inevitable, so for unnecessary trouble, flower friends should remember the above prevention and control methods.

What if there are bugs in the lotus bowl? Cleaning methods of bugs in bowl lotus water

Nelumbo nucifera is a perennial aquatic herbaceous flower of lotus family. The underground stem is long and thick, with long nodes and round leaves. Florescence from June to September, solitary born at the top of the pedicel, petals most, embedded in Huatuo hole, there are red, pink, white, purple and other colors, or color patterns, edge. Nuts oval, seeds ovate. In the past, many flower friends will find bugs in the water where they raise lotus bowls, which is more troublesome to be clear. here are the clear methods of collecting bugs in lotus water for flower friends' reference.

NO.1 wiggler

The larva of mosquitoes. This is probably the most common bug in open-air culture. Because of the water, the female mosquito will come to the water to lay eggs, and then a bunch of mosquitoes will grow in everyone's basin.

Swimming mode: twisting left and right

Color: it is said to be white.

Solution:

1. Put in some small fish

Koi is not recommended, small tropical fish such as peacocks are recommended. Koi is a cold-water fish, and the bowl lotus is exposed to the sun every day, which is not conducive to the growth of carp (if your goal is to collect dried fish, that's fine; if you have a set of pots, of course, if the outer basin is big enough). Parents who are going to raise peacock fish should pay attention. According to my observation, peacocks usually jump into pots when they are scared, so don't move flowerpots, don't knock on flowerpots, etc., or you'll have to wait for the fish to dry, especially when you first get out of the fish.

Advantages: original ecology. Disadvantages: if the water is shallow, you can only wait for the fish to dry.

2. Pickled oleander leaves

Soak some oleander leaves in water, it is said that the effect of chopping is better, and the effect of mashing into juice is better. Oleander juice is highly toxic, you must pay attention to it! Be sure to wear gloves (impermeable) during operation, wash hands after operation, and properly handle used utensils to avoid poisoning.

Advantages: being able to kill bugs is an advantage. Disadvantages: oleander juice is highly toxic, to be safe, so finished lotus leaves and lotus roots can not be eaten.

3. Mosquito-repellent incense

It is said that electric mosquito-repellent incense tablets also work.

Advantages: killing mosquitoes. Disadvantages: think for yourself, I can't figure it out. Not ecological?

4. Spraying pesticides

Spray pesticide gently into the water, be careful not to spray on the leaves. Pyrethroids pesticides will decompose after a few hours, even if three or two bad leaves do not affect the overall health of bowl lotus. There is also a kind of thing called flower protector, I don't know if it is a pesticide. It is best to wear a mask when spraying to avoid poisoning and protect your health. (seen in the post bar)

Advantage: it's a little bit to be able to kill bugs. Disadvantages: burning leaves; difficult to grasp the dosage

5. Syringe

This method is to suck it out with a syringe.

Summary: the above methods, or the most recommended fish culture, the original ecology.

Attached picture (never grown in my basin, a picture given by du Niang):

NO.2 chironomid larvae.

Cylindrical worm-shaped, slender body, full-length 2-30mm, also known as red wiggler. It has the effect of purifying water quality and is an excellent bait for fish (so you know the solution).

Color: red

Solution:

1. Various methods of wiping out wigglers together.

2. Mash it with ginger and garlic, wrap it with gauze and soak it in a basin. (it also seems to apply to wigglers.)

Advantages: effective. Cons: it tastes good.

NO.3 water flea

The total length of the body is about 1-3mm, light flesh red (du Niang said this color), oval, left and right flattened, back-end extension and growth of thorns (shell thorns). Parthenogenetic reproduction. So, if you have one matrix, you can give birth to a pile. I won't talk about the principle of swimming, the concrete form is like jumping in the water. Excellent bait for fish (so everyone knows how to get rid of it).

Solution:

It is said that there are not many water fleas, which are relatively rare. Moreover, the general water fleas as live fish food, everyone is trying to figure out how to feed them, so the solution is …... Ahem, I can only recommend fish, which is the most accurate and ecological.

In addition, water fleas will die if they do not surface to breathe. According to the phototaxis of water fleas, they may die if they are shaded for a day. However, this is only a theoretical method, after all, no one will abuse the bowl lotus in order to kill water fleas.

Photo: (still thanks to du Niang)

NO.4 water barge or water pontoon

This thing should not be familiar to everyone. If it wasn't for the dredged lotus pond mud, if it wasn't for the dredged lotus pond mud that had been scalded, and if it hadn't been ironed or cultivated indoors, I would have admired it very much (in fact, it's impossible. Forgive the landlord for making a joke).

This insect can be found in lotus culture is extremely rare, generally appear in outdoor breeding. (no one in the bar has mentioned that this kind of bug has grown in his basin.) Its scientific name may be strange to everyone, and then LZ will tell you that it is commonly known as dragonfly larvae. Some people will "Oh", some people are still confused. What does a dragonfly larva look like? LZ will attach a picture.

The insect is brown or dark green and likes to stay in places where water and grass are dense, or under withered leaves. When I was young, I didn't look at LZ carefully. I once thought it was a spider living in the water (don't laugh at LZ).

Solution:

Why do we have to solve it? While raising lotus, you should raise dragonfly to play well. And it is carnivorous and eats other insects in the water (such as mosquito larvae). = =. The old enemy of fate!), tadpoles, etc.

Special reminder! If this thing is found in the lotus bowl, do not put fish! Otherwise, you won't even get dried fish, and you won't have any ashes left. The adult larva of a dragonfly can eat a hundred loach seedlings a day (LZ is not meant to scare you). Dragonfly larvae are absolutely ferocious!

Attached pictures (more pictures will be given to you by du Niang):

NO.5 all kinds of snails

It is well known that snails eat green algae and are good helpers for algae removal. But if you want to remove filamentous algae, you should pay attention to it. Not all snails eat filamentous algae. As far as LZ knows, apple snail, zebra snail and onion snail eat algae, while mysterious snails eat seaweed at the same time.

LZ listed this because the cylinder burst was horrible (20, 000 words were omitted here).

In addition, if the pond mud is not properly treated after being dug back, snails will probably grow. After the pond mud is dug back, it must be exposed to the sun (do not release water) and scalded with boiling water. The snail will die naturally if it loses water. You asked LZ how could he know?

Solution:

1. Turn over the vat, dry the soil again and burn the soil again. In this way, other insects will basically die.

Advantages: effective. Disadvantages: tedious.

2. Fish culture while releasing snails. It is said that the fish will eat the eggs that the snail has just laid.

Advantages: simple and ecological. Disadvantages: it is difficult to estimate the shallow water when raising fish and snails together.

3. After raising snails, always observe whether there are sticky or frozen things on the back of the floating leaves, and if so, wash them down to other places immediately. These things are small snails. (this message thanks to your friend Li Jiehao for sharing.)

Advantages: prevention is the first. Disadvantages: you always have to turn the lotus leaves.

Conclusion: snail farming should be careful, you know.

Once this thing is raised, it is difficult to eradicate it. Do not raise snails that are prone to tank explosion, such as apple snails. Zebra snails and onion snails will reproduce slightly more slowly, and some places that sell fish will sell them. One basin is enough, remember! Or you'll regret it. You asked the landlord how to know?

NO.6 red nematode

Red nematodes, known as water earthworms, are slender and long, up to 100mm. They look disgusting and are a favorite live food for goldfish and koi. When you are frightened, you will quickly shrink to the dirt, and there are many sellers in the fish market. However, if you have red nematodes in your water, you should pay attention to whether you should change the water. The breeding of red nematodes means that the water is organically contaminated.

Color: red

Swimming mode: peristalsis

Solution:

1. Fish farming. LZ has always advocated the original ecology, no pollution, fish farming is the best solution.

Pros: no repetition. Disadvantages: many restrictions are not repeated.

2. Raise shrimp. Shrimp also eat red nematodes, but if there are many red nematodes, you need a group army to fight.

Advantages: the same fish. Disadvantages: no (is there anyone's shrimp who also jumps into the tank? You can share it, ahem.

3. Use pesticides and do not repeat them.

4. Oleander leaves will not be repeated.

Be sure to change the water after the appearance of the red nematode, otherwise the water may stink soon. There are other ways to remove red nematodes. Be sure to share them.

Above mentioned insect pests, let's talk about the common diseases of bowl lotus:

Disease prevention and control:

1. Spot blight

At the initial stage of symptoms, the leaves turned green, and the surrounding tissue necrosed into irregular disease spots, light brown to dark brown; the floating leaves on the water surface were dark to dark gray, with large wheel-like patches and upper small black particles.

Pathogen: mildew in warm leaves. The conidium is subglobose and oblate, and the primary leaf epidermis is slightly raised after burying, brown, 136-195 μ m in diameter. Conidia elliptic or fusiform, slightly curved, slightly pointed and colorless at both ends, unit cell, 6-9 × 2-3 μ m, containing 1-2 oil balls.

Prevention and treatment: remove diseased leaves and remove diseased remains and burn them. Spray o.5% Bordeaux solution or 70% topiramate 1000 times solution.

2. Anthracnose of lotus paniculata

Symptoms: the disease occurs on the leaves, with small brown spots, then the spots expand into near-round spots above 10mm, and the edge of the spot is dark.

The pathogen is Gloeosporium nyrmphaeae Hemmi et Kawase, which belongs to half-known mycosis. The diameter of mycelium is 2.56.0 μ m. The size of conidia is (8.0-12.0) μ m × (3.0-5.0) μ m.

The route of transmission: the pathogen overwintered in the conidium on the injured plant tissue and spread in the air.

Prevention and treatment: the disease residue was collected and buried or burned in ① growing season. ② application of mature organic fertilizer, timely and appropriate amount of topdressing, so as to achieve the combination of organic fertilizer and chemical fertilizer, nitrogen fertilizer and phosphorus and potassium fertilizer. ③ was sprayed with 50% carbendazim WP, 75% Chlorothalonil WP, 36% carbendazim suspension, 50% carbendazim WP or 80% anthrax Fumei WP every 10 days or so after timely removal of the diseased plant, spraying 1500 times of carbendazim WP, 75% Chlorothalonil WP, 36% methyl thiophanate suspension, 50% carbendazim WP or 80% anthrax Fumei WP every 10 days or so.

Conclusion: the above is the introduction of the growing bugs in the bowl lotus water. I hope it will be helpful to the flower friends who grow bowl lotus.

Family flower cultivation, family flower cultivation skills and tips

Planting and cultivating flowers is one of the ways that modern people rely on for entertainment. There are countless famous poems praising flowers through the ages. It is impossible to understand this kind of natural pleasure without planting and raising flowers. However, what do you need to pay attention to?

First of all, it is necessary to grow suitable flowers. Some flowers are not only beautiful in appearance, but also can absorb indoor harmful gases. For example, hanging orchids and aloe vera can absorb formaldehyde from newly installed houses; plum blossoms and carnation can absorb sulfur dioxide in the air; daffodils and chrysanthemums can absorb nitrogen oxides. Most flowers carry out photosynthesis and exhale qi during the day, while cactus is just the opposite. If they are mixed and planted together, they can maintain the output of nourishing qi, which is beneficial to the body and mind.

Secondly, do not raise flowers with strong fragrance or irritating or even toxic smell. The aroma of roses and lilies is rich, but if placed too much, it is easy to stimulate the brain and cause sleeplessness at night; the aroma of tulips can cause skin allergies and other diseases; oleander stems and leaves, petals are poisonous, if accidentally eaten, it will be poisoned. Also, if there are too many flowers, it emits a lot of carbon dioxide at night, which is also bad for the human body.

Finally, the mentality of growing flowers should be adjusted well. Flowers are also life, need water and sunshine, do not miss the time of watering, do not keep them out of contact with the sun for a long time; fertilize properly, do not let flowers be bitten by mosquitoes. At the same time can not be too loving, is not watering, easy to fiddle with, flowers need to rest, frequent interruptions are easy to make them tired. There are also some people who do not raise valuable flowers, most of which are cultivated in harsh conditions, and if these people do not have the time and energy, they can only be happy in vain.

Knowledge of family flower cultivation 1. Watering

1.1 selection of water quality

Family flower watering often uses tap water, but tap water contains disinfectant bleaching powder, in which chloride ion is easy to hurt the young root hairs of potted flowers, which must be stored for 1 to 2 days. After chlorine volatilization, the water temperature is close to the soil temperature before it can be used to water flowers. Due to the natural arrangement of water molecules, magnetized water has been disturbed by the magnetic field, which is similar to the water molecules in plant cells, and is easy to be absorbed and utilized by plants, so it is best for potted flowers to pour magnetized water.

1.2 watering capacity

1.2.1 watering principles

The principle of watering is "pour thoroughly, pour thoroughly without leakage", that is, each time until the water seeps from the plate under the basin. In addition, it should be determined according to the size, depth and texture of the flowerpot. Small basin shallow, watering should be less frequently; mud basin seepage is good, basin soil is easy to dry, should be watered frequently; stone basin, glaze basin is not easy to seep, long-term stagnant water, flowers will rot.

1.2.2 watering period

Different flowers and trees have different watering periods. One is the wet rather than dry type, which means that when the basin soil is completely dry, the flowers and trees will be damaged and withered, and this kind of flowers and trees should be fully watered when the basin soil is slightly dry, such as iron line fern, Phoenix tail fern, etc.; the second is the dry rather than wet type, which refers to the flowers and trees that are watered after the basin soil is dry, such as cactus, aloe, etc.; the third is the wet type, which refers to the flowers and trees that are immediately watered by 3cm on the surface of the basin soil, such as turtle back bamboo, green apple and so on.

1.2.3 watering season

When the spring is cold and warm and the weather is changeable, the potted flowers begin to sprout and take root, requiring a large amount of water, so as to keep the basin soil moist; dry in summer, evaporate quickly, and double watering; water should be watered less in autumn to avoid excessive growth of flowers and branches, affecting the blooming of the second year; in winter, most flowers and trees are dormant and keep the pot soil slightly dry.

1.3 watering time

The time of watering flowers varies every day in spring, summer, autumn and winter. As the flower proverb goes, "morning water is nectar, fire water is arsenic, and evening water is life-saving soup." That is to say, in the spring and autumn season, about 10:00 in the morning and after 4 o'clock in the afternoon is the appropriate time to water flowers, but do not water flowers at noon in summer. The temperature is the highest at noon in midsummer, and the difference between basin soil and water temperature is the greatest. At this time, watering flowers can easily hinder the normal physiological activities of the root system, weaken the water absorption of the root system, produce physiological drought, and wilt the branches and leaves. By the same token, flowers should be watered at noon in winter. In short, "Spring watering noon, summer watering morning and evening, autumn watering the next day, winter watching frequently."

1.4 watering method

Potted flowers must be chiseled loose before watering, so that the irrigated water can be absorbed in time so that it will not emerge from the edge of the basin. It is best to pour water evenly with a fine-hole spray can. The watering of small pots of flowers had better take the method of basin soaking, that is, put the flowerpots into the larger water basin, make the water seep into the basin soil from the drainage hole, and move out after the surface of the basin soil is slightly wet, which can prevent the pot soil from hardening due to watering, which is beneficial to the root respiration of potted flowers. General negative foliage potted flowers in the special environment of the dry room, coupled with the cover of dust, it is often difficult to show bright colors. In addition to regular irrigation, we should also adopt the foliar spraying method of sprinkling water to wash dust and spray to moisten the leaves. This method can also cool down the summer potted flowers at high temperature at noon and continue to bloom well for the semi-summer dormancy flowers.

2. Fertilization

2.1 types of fertilizers

2.1.1 Organic fertilizer

Organic fertilizer is a kind of fertilizer formed by the processing and ripening of seeds, organs, residues or excreta of all kinds of plants and animals, such as human feces and urine, livestock and poultry dung, cake, dregs, weeds and green manure. Organic fertilizer is a late-acting fertilizer with complete nutrients and long fertilizer effect. It must be fermented and ripened before use.

2.1.2 Inorganic fertilizers are fertilizers made from chemical synthesis or natural ore processing, such as urea, calcium superphosphate, potassium dihydrogen phosphate, etc. The fertilizer effect of inorganic fertilizer is fast, but the nutrient is simple, and the fertilizer effect is not long. Fertilizer is single, but if it is used alone for a long time, it will harden the basin soil and it is better to use it in conjunction with organic fertilizer.

2.2 rational fertilization

2.2.1 principles of fertilization

The principle of fertilization is timely and appropriate amount. Timely refers to flowers when needed to apply, if found that the color of flower leaves become light, or when the plant growth is weak, it is timely to apply fertilizer. Appropriate amount should be achieved at all times. Excessive fertilization will affect the growth and development of flowers. Too much nitrogen fertilizer, plants easy to grow, stems and leaves weak, affecting flowering and fruiting, and vulnerable to diseases and insect pests; too much phosphate fertilizer, will hinder the growth of flowers, affect flowering and fruiting; too much potash fertilizer, low plants, wrinkled brown leaves, and even wilt.

2.2.2 fertilization period

When growing rapidly in the seedling stage, more nitrogen and potassium fertilizer should be applied to make the stems and branches stout and the root system developed; before flowering and budding, more phosphate fertilizer should be applied to promote large flowers, beautiful color and full buds; spraying potassium dihydrogen phosphate after color penetration and thanks can prevent falling flowers and buds; during flowering and early fruit setting, it is necessary to control fertilizer and water, otherwise it is easy to drop flowers and fruits.

2.2.3 fertilization season

The winter temperature is low, the plant growth is slow, most flowers grow in dormant or semi-dormant state, generally do not apply fertilizer. The spring and autumn season is the peak growing season, so more topdressing should be appropriate. High temperature in summer, rapid evaporation of water, exuberant growth of flowers, adhere to the principle of frequent application of thin fertilizer. The application of organic fertilizer must be fully ripened. The concentration of chemical fertilizer should not be too high to prevent flowers from "burning".

2.2.4 fertilization time

The fertilization time is different in different seasons. Fertilization should be applied in the evening in summer and around noon in winter. General fertilization can be applied before dry or rainy weather in sunny days, but not after rain and continuous rainy days; when the climate is warm and hot, it is not applied when the climate is hot or cold; when the climate is hot or cold, it is semi-dormant or dormant; when the basin soil is dry, it is not applied when it is wet; the old basin soil is applied more, but the new basin soil is applied less; the base fertilizer is applied less, and there is no base fertilizer or not enough.

2.2.5 fertilization according to the characteristics of flowers

Flowers dominated by foliage, such as pine, bamboo, orchid, etc., are mainly nitrogen fertilizer, which can promote the growth of branches and leaves and have a thick green color. Flowers that mainly watch flowers and enjoy fruits need more fertilizers. When growing branches and leaves, fertilizers based on nitrogen fertilizer are applied once or twice, and in the stages of flower bud differentiation, flower bud formation and growth before flowering, fertilizers based on phosphate fertilizer should be applied to make the flowers multiply and fruit luxuriantly. Generally speaking, for newly transplanted flowers with disease, do not apply fertilizer for the time being; it is best not to apply fertilizer to flowers in the flowering period, so as not to wither and fall the buds and flowers.

2.3 fertilization methods

2.3.1 Base fertilizer

The application of base fertilizer generally adopts two methods: one is to cultivate flowers after uniformly mixing the fertilizer with the cultivated soil (about 1:9) according to a certain proportion, which can not only improve the physical properties of the soil, but also supply the nutritional needs of the whole period of flower growth. The second is to put a little fertilizer on the pot, change the basin or turn the basin into the bottom of the basin, generally not more than the basin soil 1 big 10, and above to cover a layer of soil, and then plant flowers.

2.3.2 topdressing

Topdressing generally uses two methods: one is soil application, that is, fertilizer is applied directly into the soil. Topdressing liquid fertilizer should first be diluted and sprayed into the basin soil, while topdressing solid fertilizer can be evenly sprinkled on the surface of the basin soil, and then covered with a layer of soil. Pay attention to watering after fertilization to facilitate absorption. Second, foliar spraying, also known as extra-root topdressing, has the advantages of saving fertilizer and quick effect. It is usually used in the peak period of flower growth or when there is a lack of certain elements. Generally, inorganic fertilizers with a concentration of 0.1% to 0.5% are sprayed in the morning or evening when there is no wind, so as to make the leaves moist, the most commonly used are urea, potassium dihydrogen phosphate, calcium superphosphate, ferrous sulfate and so on.

3. Control of common diseases and insect pests

3.1 Diseases

3.1.1 diagnosis and hazards

① powdery mildew. Diagnosis of powdery mildew: yellow transparent spots appeared on the leaf surface, and then gradually spread to the whole leaf. Powdery mildew spots appeared and the disease spots turned gray in the later stage. It mainly harms many kinds of flowers such as rose, rose, dahlia, chrysanthemum, peony, melon and leaf chrysanthemum, impatiens, wood and so on.

② anthrax. Diagnosis of anthracnose: yellow-brown sunken spots appeared on the leaves, and spread outward into dark brown patches, or irregular patches on the leaves, and the leaf tips dried up and spread downward continuously. In the later stage, there are black dots on the disease spot, which are often arranged in a round pattern, and the leaves die when the disease is serious. It mainly harms orchids, rubber trees, roses, cacti, peonies, jasmine, carnation, anemone and other flowers.

③ black spot. Diagnosis of black spot: nearly round or irregular black spots appeared on the damaged leaves, which gradually enlarged, and in severe cases, the leaves turned yellow, fell off, and even led to plant death. It mainly harms rose, rhododendron, camellia, cherry, elm leaf plum and other flowers.

3.1.2 Prevention and treatment

① agricultural control. Strengthen cultivation management, properly increase the application of phosphorus and potassium fertilizer, enhance plant disease resistance, and should remove disease and fallen leaves as soon as possible, and incineration, clean the environment, reduce transmission media; pay attention to ventilation and light transmission.

② chemical control. Spraying 1 ∶ 1 ∶ 100 Bordeaux solution to protect the disease in the early stage of the disease; spraying antimicrobial agents 50% carbendazim, 50% carbendazim, 65% zinc, 75% chlorothalonil, 50% topiramate 500 times, 50% benzoate 1000 times in the early stage.

3.2 insect pests

3.2.1 aphids

Aphids, also known as greasy insects, can occur all the year round, mainly to harm three-leaf plum, chrysanthemum, pomegranate and so on. The leaves of the injured plants were curled and the branches and leaves turned yellow, resulting in a large number of leaves and flowers falling off, and in serious cases, the plants died quickly.

Control methods: soak red pepper 50g, 30g 50g of water for 24 hours, spray the damaged plants with its filtrate, the control effect is very good, or spray 40% dimethoate EC 2000 × 3000 times, 50% aphid pine, EC 1000 times 1 500 times or 80% dichlorvos EC 3000 times.

3.2.2 Red Spider

Red spiders, also known as fire dragon bugs, occur for many generations a year. It mainly harms the leaves and petals of wild elm, sparrow plum, five-needle pine and so on. The body of a red spider is the size of a needle, crimson or purple, and only red dots can be seen with the naked eye. The leaves of the injured plants turned green and the leaf edges rolled upward, resulting in scorching and shedding, causing the buds to atrophy in the early stage and die in severe cases.

Control method: soak citrus peel with 50g 0.5kg with water for 24 hours, spray the plant after filtration, or spray dicofol 1500 times or 40% omethoate 2000 times for control. When spraying, the leaf surface and back should be sprayed together for better effect.