Control measures of ornamental fern diseases and insect pests

There are relatively few pests and diseases of ferns, but most ferns like to grow in high temperature and high humidity environment, and the harm of pests and diseases is inevitable. It should also be prevented in the process of cultivation management to improve the ornamental effect. First, infectious diseases are caused by germs, which make ferns appear various spots and affect their appreciation. Serious injuries can also lead to death. There are mainly anthrax, brown spot, nematodiasis, rust, sooty blotch, damping-off and so on.

1. anthrax. Fungal diseases, characterized by pink sticky substances at the diseased spots, mainly harm young leaves of plants. At first, the damaged part is a round and nearly round dark brown spot at the leaf edge or tip, which is soaked in water, and then it gradually expands from several diseased spots to irregular spots and turns brown in color. Some lesions are cloud-shaped, with reddish halo on the edge, and turn gray in the middle of the lesions in the later stage, with many tiny black spots. If it is serious, the whole leaf will die. The soft growing point of Boston fern was invaded by this pathogen, and the top turned brown and withered, which damaged the commercial appearance of the plant. Pathogens overwinter on diseased leaves in the form of mycelium, conidia or ascomycetes. When the temperature rises to 20℃ and the relative humidity exceeds 75%, it begins to get sick. Germs spread by rain, and spread rapidly at 25℃ and humidity of 80%~90%. Prevention and control: the disease is mainly prevented, and spray prevention is carried out in rainy season and high temperature and high humidity season when new leaves are formed. The disease can be prevented by adjusting the temperature, humidity and ventilation conditions in the greenhouse, keeping the leaves dry, putting an end to the introduction of diseased plants and thoroughly removing the sick and disabled nearby. Spraying 1 time every 7 days and continuously spraying for 2~3 times before or at the early stage of onset can get good results. The effective pesticides are 75% chlorothalonil 500 times solution, 50% carbendazim wettable powder 800~ 1000 times solution or 70% thiophanate-methyl wettable powder 800~ 1000 times solution, and fungicides such as Sheng Da, Lideke and Spock also have good control effects.

2. Brown spot disease. Brown spot of ferns, also known as leaf spot or leaf blight, often occurs at the top of leaves. The damaged blade was a round black spot at first, and then it expanded into a round or nearly round shape. The edge of the lesion is dark brown, the center is gray-black, and there are small black spots. After that, the lesion expanded rapidly, and the leaves eventually turned black, dried up and died. Its main transmission route is deciduous leaves, which may occur in spring, summer and autumn, and it is easy to be popular in hot and humid seasons. Prevention and control: isolate and spray the diseased plants immediately, or cut them down for centralized burning and spray them for protection. 50% carbendazim 1000 times solution, 50% thiophanate-methyl 1000 times solution and 200 times bordeaux solution can be used for control. Too much watering or too high humidity is also prone to brown spot disease. At the early stage of the disease, 50% mancozeb aqueous solution can be used for 300-400 times and 70% thiophanate wettable powder for 800- 1000 times.

3. Nematode disease. Also known as root-knot nematodes or root-knot nematodes, the pathogen is white linear soft worms with two tips. The diseased plant wilted with brown spots and gradually died. Many kinds of pteridophytes in greenhouse are damaged by nematodes, which can be identified by a red-brown or black strip line extending from the midvein to the leaf edge. Put a small brown patch into the water and observe it under the microscope, and you can clearly see the bugs moving around. Prevention and control: removing damaged leaves and eliminating their growth conditions is conducive to reducing the harm of nematodes. Using 10% dichlorvos, chlorhexidine or 25% phosphate, covering fresh loess and watering a little water after application can significantly reduce the population density of root-knot nematodes. Hot water treatment can also be used to prevent nematode damage of nest fern. Before planting, soak the plants 10~ 15 minutes in 43℃ hot water.

4. rust. Ferns will rust, such as Cuiyuncao. In March-April every year, basidiospores are produced on the contralateral veins at the base of young leaves, which invade the productive spores and rust spores of plants. In May, pale yellow powdery summer spores were distributed on the leaves, and then brown winter spores were produced. If a large number of spore apparatus invade plants, plants will grow poorly.

Prevention and control: 65% zineb wettable powder 500 times solution, 1: 1:50 bordeaux solution can be used for prevention and control, and spraying/kloc-0 every/0 ~ 1 5 days for 3~4 times, which can achieve certain effect.

5. Black spots. The leaves of ferns are covered with spores and mycelium of black mold, which usually grow on honey dew secreted by scale insects and other sucking insects. Nicotine and soap should be sprayed repeatedly to control scale insects and other spiny insects.

6. Sudden illness. The disease is caused by two or three different fungi, which makes the original leaves soft, black and disintegrated, and often occurs when sowing and propagating ferns. Fern spores should be sown on steam sterilized soil or watered with diclofenac solution, which is also helpful to resist damping off.

Second, physical diseases.

1. sunburn. Most ferns prefer warm and semi-cloudy, and are not resistant to strong light. The suitable light intensity is 1000~6000Lx. Strong direct light will dry, dehydrate, yellow or scorch the leaves. Prevention and control methods: fern leaves can remain evergreen in semi-shade state with 2~3 hours of sunshine; The burnt fern leaves should be carefully maintained to avoid being stimulated by strong light, in addition to being cut off in time to keep them tidy.

2. Humidity disorder. The air is too dry, which can easily lead to leaf curl, so water more in spring and summer. However, in summer, the soil of Pteridium aquilinum cultivation should be kept wet, but not too wet, so as not to cause poor root growth; At the end of autumn, control the water and keep it slightly wet; Water spraying should be reduced during hibernation to avoid leaf rot.

3. The temperature is uncomfortable. ① High temperature hazard. Most ferns need a suitable temperature of 18~25℃. Short-term high temperature in midsummer will also make fern leaves wither and scorch. Therefore, from the end of April, it is necessary to cover the sun, sprinkle water on the ground and ventilate to reduce the temperature. ② Low temperature hazard. Semi-hardy ferns, such as Adiantum. Pteridophyte, such as Dryopteris tricuspidata, which requires a temperature not lower than 5℃ and is not cold-tolerant. , bird's nest fern and Dryopteris squamosa. Should not be lower than 10℃. If the temperature is too low, the leaves will be damaged, causing wilting, blackening and even plant death. Measures such as covering, smoking and applying more warm fertilizer can be taken to ensure safe wintering.

4. malnutrition. (1) element deficiency. The lack of nitrogen, potassium, calcium, magnesium, sulfur and other elements in the soil is easy to cause the abnormal growth and development of ferns. Calcium-loving ferns, such as Adiantum, Adiantum argenteum and Pyrrosia, can be mixed with a small amount of lime, bone meal or broken eggs (shells) in the cultivation soil. Osmunda japonica, Dryopteris cibotii, Pteris nidulans, Pteris nigricans and other acid-loving ferns should be sprayed with 0. 1%~0.2% ferrous sulfate solution regularly or combined with fertilization, and watered with alum fertilizer. ② Real disease. Mainly refers to the surplus of elements such as nitrogen, phosphorus, manganese and boron. When the fertilizer damage is serious, it can be saved by washing. The specific method is to loosen the soil and wash it with long running water for half a day. General flushing 1~2 times can be effective. In production, we should pay attention to the frequency of fertilization and fertilizer concentration, and try to use farm manure with long-lasting fertilizer effect, such as manure, bone meal, cake fertilizer and plant ash. So as to maintain the vigorous growth of ferns.

Third, common pests

The main pests of pteridophytes are scale insects, aphids, red spiders and slugs. 1. ichthyosis. Among many kinds of scale insects, scale insects and scale insects are the most serious, and other scale insects are rare. Scale insects parasitize on the edge or back of fern leaves, and their larval stage is very short and their actions are slow. When they move to the back of the leaves, they begin to crust and suck the juice from the plants with piercing mouthparts. Scale insects reproduce faster. If there are more insects, it will inhibit the growth of plants and cause them to wither. In severe cases, the whole plant will wither and die, and sooty blotch will be induced. The damaged leaves have spots, which affect the growth and appreciation. Female adults can give birth to young scale insects continuously, and the larvae can grow into adults in two months. The newly hatched nymph has poor drug resistance, which is the key period of chemical control. There is no specific medicine for prevention, and it is generally based on prevention. Pay attention to keep the environment ventilated during inspection. When planting ferns, it is necessary to control the leaves not to be too wet, check the front and back of the leaves frequently, and adopt manual brushing when a small number of pests occur; The peak of scale insects is in late May. At this time, 40% omethoate emulsion, 50% malathion, 25% isophos and 80% dichlorvos emulsion can be sprayed with 1000 times solution. Malathion spray is very effective against scale insects in crawling stage. Repeated spraying of nicotine and soap can also remove scale insects. When the pest is serious, cut off the whole leaf and burn it. A few ferns are allergic to organophosphorus, so they should be tested before application. We should also pay attention to and make use of natural enemies of scale insects such as Rhodotorula.

2. aphids. There are two kinds of aphids, black and green, which usually appear in early spring and early summer and often live in groups at the buds of ferns. When it is harmful, use the stinging mouthparts to suck the juice in the plant, so that the growth of the plant stops and the leaves turn yellow. In addition, the secretion of aphids often leads to the parasitism of various molds, which is easy to produce sooty blotch. It can be washed with soapy water first, then sprayed with 40% dimethoate or omethoate 1000~ 1500 times, pyrethroid 2000~3000 times, derris 2.5% 1000~ 1500 times and trichlorfon 600 times.

3. Starscream. Red spider is a kind of mite, small in size and fast in reproduction. It can reproduce about 1 0 generation in1year. Starscream sucks the juice of ferns with its sharp mouthparts, which makes the growth of plants stagnate and leaves turn yellow. Because of its small size and rapid reproduction, it is difficult to be found by naked eyes, and if it is not prevented in time, the harm will be very serious. In hot season, dicofol 800~ 1000 times solution and 50% omethoate 1000 times solution are used alternately for control.

4. slug slug, also called slug, belongs to Gastropoda, slug family, and is shaped like a snail with a shell. The shell usually degenerates and the mantle covers the whole back. Two pairs of antennae, the second pair has eyes at the top. The lung hole is opened on the front right side of the body, and the body can secrete mucus, leaving silvery white stripes after crawling. In early summer, white eggs are laid under bark and stones. Slug is one of the main pests that harm ferns. They are often hidden in the inner walls of pots and pans, leaking holes at the bottom, or under the covers of plants and soil surfaces. They like to go out to eat the shoots and leaves of ferns at night. Spraying 70~ 100 times ammonia at night from 22 to 23 can achieve the purpose of fertilization. Manual capture can also be used. The regeneration ability of slugs is very strong, and the caught slugs should be thrown into hydrochloric acid solution to kill them. In the warm and humid environment, in addition to slugs, there are a large number of small animals such as snails and rat girls, eating fern leaves crazily; Earthworms devour the young roots of ferns and make their growth stagnate. Can spray mirex, snail powder, mirex or lime, spray ammonia, high-concentration brine, copper sulfate, etc. , and artificially killed.

Fourth, the harm of moss and lichen.

These plants will not directly harm ferns, but can shade and affect the original leaves and small plants of ferns. They spread quickly and can spread all over the ground quickly, preventing water and nutrients from entering the soil and affecting the growth of ferns. Treatment method: disinfect the soil with distilled water before sowing spores to avoid other spore plants polluting the soil. In addition, unclean watering equipment is also one of the pollution sources. It is a good way to avoid harm by providing suitable temperature and fertilizer to make the original leaves of ferns grow and mature quickly to reduce the influence of other spore plants.

Pest control of fennel

Fennel, also known as fennel, coriander and so on. It is planted in all parts of the country; The height of the plant is between 0.4m, the flowering period is from May to June, and the fruiting period is from July to September. These flowers are small and yellow. Friends who have cooked should know that fennel is both a seasoning and a vegetable, and its fruit is still a traditional Chinese medicine. Let's talk about pest control in daily farming.

disease

powdery mildew

At the beginning of the disease, white spots will appear on the leaves of plants, and then they will gradually expand. In severe cases, the whole leaf will be necrotic.

gray mold

The disease mainly harms the leaves and petioles of plants, and will cause the leaves and petioles of plants to rot when it occurs.

root rot

As the name implies, the main damaged part is the root, which will directly lead to the death of seedlings at seedling stage, but will lead to root rot at mature stage, and the plants can be pulled out of the pot soil with a little drag. In severe cases, it will cause the whole plant to die.

Sclerotinia sclerotiorum

This disease mainly harms the petioles and stems of plants. Soften first after illness, and then slowly decay.

viral disease

It can harm the whole plant, in which the leaves will wrinkle after illness, and it will also hinder the normal growth of the whole plant and affect flowering and fruiting.

insect pest

aphid

This pest will start from the leaves of plants and reproduce very quickly. If it is not stopped in the early stage, it will spread all over the factory in a short time. In severe cases, it will cause viral diseases of plants, which will lead to the death of the whole plant.

Prevention and cure method

When pests and diseases are found, they can be removed manually at the initial stage, and then sprayed with fungicides. In the middle stage, special drugs should be sprayed, and in the later stage, the parts with serious pests and diseases should be cut off first, then the pots should be replaced with soil for replanting, and then the drugs should be sprayed for prevention and control.

First of all, we should improve the feeding environment, pay attention to high temperature and cooling, and increase air circulation.

When watering daily, you must not make the soil accumulate water or keep the soil wet for a long time.

Pest control of Rosa spinosa

This is a shrub of Rosaceae, mostly distributed in the north temperate zone. In China, it is cultivated in many provinces, such as Heilongjiang, Inner Mongolia, Shaanxi and Gansu. In addition, it is also distributed in northern Europe and Japan. We can find it on sunny hillsides, forests or bushes. Our article mainly talks about how to deal with pests and diseases.

disease

The first disease is called black spot disease, which we are familiar with. Many kinds of plants will be troubled by this disease. It mainly harms the leaves of this plant. At the beginning of the disease, some small brown spots will appear on the surface of its leaves. With the aggravation of the disease, these small spots will gradually connect into some large circular spots, and the color will gradually deepen. To prevent and control this disease, it is necessary to clean up the fallen leaves in time and cut off the diseased parts. Secondly, you can spray some medicine, such as Bordeaux potion. Of course, it is also important to strengthen management, such as drip irrigation.

The second disease is called rust, which is also very common. It may have a great impact on leaves and branches, and even cause most leaves to fall off or even die in severe cases. For this disease, it is necessary to strengthen supervision, take measures as soon as possible, and spray the corresponding medicine once every other week for three or four times in a row, which can be well suppressed.

insect pest

First of all, the scarab is harmful to the leaves, flowers, roots and other parts of this plant, especially affecting the quality of flowering. To deal with it, you can use light to trap and kill the living. If it is very serious, you must spray insecticide.

The second kind is the thorn moth, which eats leaves and causes leaf damage. For this pest, first of all, we should carefully check whether there are eggs on the branches, if there are, cut them off in time and spray with liquid medicine such as Fuling emulsifiable concentrate.

Pest Control of Rhododendron

Rhododendron wax leaves are common family ornamental flowers. Colorful flowers are very beautiful, but they are also very vulnerable to various pests and diseases. So what are the common diseases and insect pests of azalea wax leaves and how to prevent them? Let's get to know each other.

Leaf swelling disease

Leaf swelling is a disease caused by fungi, which often occurs in the seasons of spring and summer and autumn and winter, especially in late spring. The disease mainly occurs on young leaves and buds. After the onset, the leaves will swell and expand, and the front end of the affected area will be spherical. At first, there will be reddish spots, then the spots will gradually turn brown, and white powder will appear on the leaves. Then all the spots will turn dark brown, and the whole leaves will swell and curl, and finally the diseased leaves will die and fall off.

Prevention and treatment: Cut off the diseased leaves as soon as possible before the diseased spots expand and produce white powder. Be careful not to leave the diseased leaves in the pot soil and burn them all from the plants. After the diseased leaves are removed, the plants are sprayed with zineb liquid medicine for sterilization.

leaf spot

Leaf spot is a common disease of azalea wax leaves, which usually occurs in wet rainy season. At first, there will be some small brown spots, then the spots will gradually increase and darken, forming dark brown spots, black spots on the patches, and finally the leaves will turn yellow and wither. Leaf spot disease has a great influence on the growth of wax leaves of rhododendron, which will not only affect the flowering situation this year, but also affect the formation of flower buds in the next year.

Prevention and treatment methods: After leaf swelling is found, the diseased leaves should be cut off as soon as possible, and then Tobuzin liquid medicine should be sprayed on the plants for treatment.

Leaf wax disease

This disease is usually caused by an infection caused by aphids. At the onset, a layer of white or pale pink waxy substance will be produced at the tip of the blade, which will make the leaves wither and fall off.

Control method: clean all infected leaves first, and then spray the plants with copper-containing preparation for treatment. In daily maintenance, insecticides can be sprayed to control aphids and other similar pests.

Jaundice

Rhododendron wax leaves like weak acid soil environment, if the soil is alkaline, it will lead to yellowing and necrosis of leaves; If any factor goes wrong, such as improper maintenance, too much or too little water, untimely fertilization, insufficient light supplement, etc. It will cause the wax leaves of rhododendron to turn yellow. To prevent verticillium wilt, we should pay attention to reasonable cultivation according to the needs in daily life.

Junpeichong

This pest often gathers on the back of leaves to suck juice for a living, which will lead to some white and yellow spots on the diseased leaves and affect the growth of plants. In order to prevent and control this disease, we can spray phoxim and other liquid drugs to control pests.

Trichophyton brevis

This kind of insect usually breeds in summer and feeds on the juice of plants. After the onset, large leaves will fall off, which will greatly affect the growth of plants. Similarly, there are sawflies and scale insects. Insecticides can be carried out by drugs or manually. Usually, we should pay attention to the ventilation of the environment, spray drugs in time for sterilization, and maintain and prevent it reasonably.