How to control common pests and diseases of peony?

Brown spot disease: occurs in the late growth period of peony. Pale spots of varying sizes appear on the surface of the leaves, generally 3 7 mm in diameter.

In severe cases, the entire leaf surface becomes diseased and dies. It can be prevented and controlled by 400 600 times of zeb. Erythema:

It can also damage green stems, petioles, sepals, petals, fruits and even seeds. The initial symptoms of the leaves are green pin-like dots on the back of the new leaves, which then expand into purple-brown spots with a diameter of 3 5 mm, sometimes connected into patches, and in severe cases, the whole leaf is scorched. You can use 1000 times of 50% carbendazim wettable powder or 800 1000 times of 70% thiophanate-methyl wettable powder, spray 1 time every 7 8 days, spray 2 3 times.

White silk disease: It mainly occurs at the base of the stem near the ground of seedlings. After the seedlings are susceptible, the base of the stem and the cortex of the roots rot, the leaves turn yellow and wither, and the whole plant dies.

50% carbendazim wettable powder 500 800 times solution, or 50% thiophanatezim wettable powder 500 times solution. Root-knot nematode disease: causes early defoliation, and all peony leaves fall in August when the disease is severe.

It occurs year after year, and the plant is dwarfed, with small leaves, small flowers, or no flowering. It was found that the seedlings were soaked in warm water at 48 49 for 30 minutes; The soil can be furrowed or sprinkled with 98% cotton micronized agent, 30 40 grams per square meter, and the depth is about 20 cm.

Common diseases of peony include leaf spot and root rot, and the main insect pest is grub. Leaf spot disease mostly occurs in June and August, to do a good job of prevention as soon as possible, generally starting in mid-May, spraying 1 1 200 Bordeaux liquid once in 7 10 days, spraying 4 6 times in a row. Pay attention to drainage after planting.

Grubs are mainly harmful to the roots, and in recent years, ammonia has been used as base fertilizer or top dressing combined with control, and the effect is good.

The first is "anthrax", which is a fungal disease that can be harmful to many plants. At the beginning of the disease, some small brown spots will appear on some parts of the stem, and the lesions will even sink and the edges will be raised. If the humidity in the environment is too high at this time, the spots will gradually increase and become larger, and some gelatinous substances will be produced.

In the worst case, the entire stem or even the entire plant will rot. Especially during the rainy season, this disease is very common. First of all, the diseased plants should be isolated, and the damaged parts should be cut and burned to avoid endangering other parts.

In addition, it is sprayed with 75% concentration of chlorothalonil 800 times liquid or other suitable agents. In addition, it is necessary to pay attention to the amount of watering and not let the environment around the plant become too wet to avoid creating conditions for the breeding of this disease.

The second disease is called "stem rot", which can also be seen from the name to harm the stem, causing lesions to appear near the stem, and then soft rot and water loss, and finally only the dry outer skin remains. Once a diseased plant is found, we must cut off the diseased tissue in time, disinfect the incision, and then repot it, and disinfect the soil with lime milk. In addition, we also need to water sparingly and pay attention to drainage.

Here we are talking about one type of pest, which is the "red spider". Its reproductive ability is very strong, so the corresponding harm is also relatively large, especially when there is high temperature and little rain. To get rid of this pest, we can spray it with 40% dimethoate solution, once a week, three times in total.

Peony is a plant that we often see, and it is a plant with strong ornamental properties. So what are the more common diseases in the process of peony seeds? How can we prevent it?

The common diseases of Mutong Huihuadan mainly include leaf spot, brown spot, rust, powdery mildew, root-knot nematode, anthracnose and so on.

The pathogen of leaf spot disease is mostly fungi of the genus Hairy, which mainly infects leaves and new branches. Generally, 15 days after flowering, that is, in mid-May, the initial stage of the disease occurs, and it worsens with the rise of temperature in mid-July. Manifestations:

At the beginning, there are brown spots on the back of the leaves, the edges are slightly dark, and they are irregular circular ring-striped dead spots, and the leaves are scorched and withered after the dead spots are connected. The fungus overwinters in diseased plants, stems, leaves, and soil.

Prevention and control methods: before winter, the fallen leaves will be burned to eliminate the source of disease, and the Bordeaux liquid (1 1 160 times) will be sprayed in time after flowering, once a week to the end of July.

The source of brown spot disease is Nigrospora, which mainly damages leaves. In the initial stage, the dorsal appearance of the leaf is 2?10mm dots, the center fades to yellow-brown or gray-brown. The front is a fine black dot and villous under the microscope. When the temperature is high and the humidity is high, the incidence of this disease is at its peak.

Prevention and control prescription laughing method: remove the diseased leaves in time and clean them, spray 10 times with 75 chlorothalonil 800 times liquid and 50 mancozeb 500 times liquid during the onset period1 time in 15 days, continuous spraying for 2?3 times.

The source of powdery mildew is Paeonia alba. In the early stage of the disease, a layer of white powdery spots is formed on the front of the leaves, and in the later stage, there are white powder layers on both petioles and many small black spots are microborn, which is the closed capsule shell of the pathogen. It usually occurs in early May, with a peak incidence in late August.

Prevention and control method: spray 20 rust 1500 times liquid at the beginning, 10?1 time in 15 days, 3 times in a row.

Root-knot nematode disease mainly harms the roots of peony, the roots are clustered fine roots after damage, and the disease will make the plant weaken day by day, and the leaf edge will turn yellow after flowering to the whole leaf scorched and fall early, and the seriously damaged will not bloom, and the plant will be short and even die.

Control methods: strengthen plant quarantine to prevent spread, and crop rotation if conditions permit. Carbofuran granules can be used, 15 grams per square meter. At the same time, the maintenance level should be strengthened to improve the disease resistance of plants.

Leaf spot disease mainly affects the leaves and shoots of peony flowers. The onset of the disease is generally about 15 days after flowering, and is most severe in mid-July. In the early stage, there will be black spots on the back of the leaves, with black edges, and the lesions will gradually connect, causing the leaves to scorch and wither.

Solution: Do a good job of prevention, after the flowers fall, spray Bordeaux liquid in time, spray once every 10 15 days, and continue until the end of July. The occurrence of leaf spot can be avoided.

At the onset of the disease, spray methyl tobuzin and carbendazim solution, spray once every 7 10 days, and spray 3 or 4 times continuously.

Peony flower yellow leaf disease is mainly caused by the lack of phosphorus in plants, which is manifested as the growth of the plant is short, the leaves are yellow, starting from the old leaves at the base of the stem, from the bottom to the top, and gradually falling off.

Solution: Replenish nutrients in time, and spray potassium dihydrogen phosphate or micro-fertilizer on the leaves after flowering.

Sclerotinia sclerotinia disease, also known as stem rot, mainly damages rhizomes and causes them to rot. At the onset of the disease, water-stained lesions appear on the stems, and white cotton-like substances appear on the soil surface. In severe cases, it can damage flower buds and leaves.

Solution: Do a good job of disinfection, disinfect the soil before planting the plant, plant after drying, and avoid the soil being too wet during the maintenance period to avoid the growth of bacteria. When the plant is diseased, the plant is dug up, disinfected and replanted. If the rot is more serious, it can be thrown away directly.

Purple striated feather disease is a fungal disease that mainly affects the root neck and roots. Purple or white flocculent matter appears on the affected part with blackened edges. In mild cases, it will form flaky patches, the roots do not grow, the branches are thin, the leaves are yellow, and in severe cases, the plant dies.

The disease mostly occurs in June and August, and gradually lessens after September with the decrease in temperature and rainfall.

Solution: Pay attention to the cleanliness of the environment to avoid the growth of bacteria in the environment. In hot and rainy weather, reduce watering and ventilate frequently. For damaged plants, the soil surface can be sprinkled with lime or sulfur to disinfect, and in severe cases, depotted and replanted.

Brown spot disease is a frequent disease of peony, and after the onset of the disease, it can be sprayed with 65% Dyszeb 500 600 times liquid. Rust is also one of the diseases, if the disease occurs, it can be sprayed with 15% powder rust 800 times. The harmful area of erythema is very large, and the leaves, petals, petioles, and seeds of peonies will be affected, and the diseased leaves need to be removed after the onset of the disease.

The main insect pests are nematodes, which can be sprayed with 15% aldicarb and 3% carbofuran**.

1. Brown spot disease.

Symptoms: Brown spot disease is a frequent disease of peonies, which can cause the leaves to dry up, which will affect the overall growth.

Prevention and control: remove the pathogen in autumn, remove the previous diseased leaves and branches, and spray a little 50% carbendazim 600 times solution before it begins to germinate in early spring. After the onset of the disease, it is necessary to spray 65% zebsen 500 600 times solution, every 7-10 days, almost 3-4 times in a row.

Peony. 2. Rust.

Symptoms: After the peony is infected, some round or irregular brown spots will appear on the leaves, causing the leaves to fade green, and yellow-brown spores will appear on the back.

Control: Plants need to be planted in a well-drained place, which can play a preventive role. If the disease occurs, it can be sprayed with 15% powdery rust 800 times.

3. Erythema.

Symptoms: The damage area is very large, and the leaves, petals, petioles, seeds, etc. will be affected.

Prevention: When pruning and pruning in winter, it is necessary to cut off diseased branches and leaves to prevent the occurrence of diseases. If the disease occurs, it is necessary to remove the diseased leaves in time, and then spray the agent thoroughly.

Peony. 4. Nematodes.

Symptoms: Nematodes can survive in 5-10cm of soil, which can harm the roots, causing problems with root function and hindering their function.

Prevention and control: After the problem is found, 15% aldicarb and 3% carbofuran can be sprayed, and the effect is relatively good.

As one of the favorite flowers of the Chinese people, peony will encounter some problems in the maintenance process, and the most common problem is pests and diseases. In fact, there are many pests and diseases that harm peony, and here we will only describe the serious and more common red spot disease and grubs, and how to prevent them.

Red spot disease, also known as leaf mold, is an important disease of peony. The main damage of this disease is the leaves and young stems, the leaves will fade at the beginning of the disease, and the small round spots will protrude on the surface of the leaves, and then gradually expand into large irregular spots of 7-12cm. In severe cases, the spots will be patched together, and eventually the whole leaf will turn brown, and the leaf will be brittle and easy to crack.

Prevention methods: Remove the diseased leaves and destroy them in time if erythema occurs; It can also be sprayed with a 600-fold dilution of 25% Duoling fungus wettable powder in early spring before the plant germination, which can kill the overwintering germs; It is best to spray 1000 times of 50% Duoling powder every 10-15 days until the leaves are spreading, which can have a good preventive effect.

Grub is the general name of beetle larvae, the body of the grub is milky white, the head is mostly yellow-brown or orange-yellow, this insect lives in the soil, will eat the roots and stems of the peony, will bite off the roots, causing the plant to shrink and die.

Control methods: plough the land before planting peonies or manually kill them when changing pots; The open-raised peony can be watered at the root with 1000 times the liquid of 50% phosphine emulsion; For potted peonies, you can add phosphine particles to the soil, about 400-500g of soil add 15-25g of phosphine particles, stir evenly and then apply it to the pot and water it thoroughly.

Peony attracts pests and diseases? Master this method, prevent and improve diseases, and make peony grow better.

1.Botrytis cinerea, seedlings to adult stems, leaves, flower buds can be infringed, seedlings are damaged, the stem base is dark green water-stained amorphous lesions at the beginning, and then turns brown, and the disease part is concave and rotten. The leaves and petioles are initially round brown with irregular whorl lines, the lesions occur at the leaf tips and leaf margins, the flowers are susceptible to diseased brown rot, the diseased stems are broken, there are black spherical sclerotia, and gray-brown mold layer is formed in humid weather.

The fungus overwinters in the diseased residue and soil, spreads by wind and rain, and is prone to disease in June and July. During the onset period, 80% zebsen can be sprayed once every 10 days with 500 times of 80% zebsen and 800 times with chlorothalonil.

2.Red spot disease, damage leaves, young stems, the leaf is now faded green slightly protruding round dots, expand into brown round or irregular large spots, with light brown wheel stripes, the back of the leaf has a light green mold layer. Brown oblong spots appear on the stems, with slightly protruding edges, ** cracked and slightly sunken.

The pathogen overwinters on the diseased stem and the diseased fruit shell, and the airflow spreads, and there is only one re-infection, and the severity of the disease is determined by the initial infection, and the high temperature and lack of rain are not conducive to the growth of the pathogen. Spray Baumé 3 5 degrees of stone sulfur mixture or 50% carbendazim 1000 times before germination in early spring to kill germs, spray carbendazim 1000 times every 10 15 days after leaf development, spray 3 4 times in a row.

3.Brown spot disease.

4.Root-knot nematode disease infringes on the new vegetative roots, producing root knots the size of nearly round peppercorns, showing the tips of aboveground leaves, the leaf margins shrinking and yellowing, and the whole leaves are scorched and fall early. It is a disease caused by a species called northern root-knot nematode.

Quarantine can be used to remove wild hosts (purple flowers), mild diseased plants, soak the roots in 49 warm water for 30 minutes to kill nematodes and then plant. The soil is mixed with 15% aldicarb granules, grams per square meter, mixed with fine soil and applied into the planting hole.

Insect pests include scale insects, beetles, spiny moths, leaf roller moths, longhorn beetles and underground pests, which should be sprayed and controlled in time.