Sweet snowball pest control methods, 2 insect pests 1 disease is the most common / pay attention to soil and environment

Every kind of plant may have diseases and insect pests. Although fragrant snowballs have strong vitality, they will also cause yellow leaves, wilt and death because of the infection of germs and pests. What are the common diseases and insect pests? What if there are diseases and insect pests in the fragrant snowballs we raise? Take a look at the prevention and control methods of diseases and insect pests of fragrant snowballs.

What are the diseases and insect pests of Xiang Snowball?

In conservation, if we do not pay attention to the planting method of fragrant snowball, it may be infected with root rot, and there may also be aphids, red spiders and other pests, the harm is not so obvious at the initial stage, but will slowly affect the growth of the plant, so we must do a good job of prevention and treatment.

Control methods of diseases and insect pests of fragrant snowball

1. Aphids

Aphids will suck plant juice, cause the leaves of the plant to wither, and secrete honeydew on the leaves, causing dry tips, scorching, withering, yellowing and so on, although it will not cause the death of fragrant snowballs at the beginning, but it will seriously affect its growth and may also cause the flowers to be dim in color.

Aphids are generally controlled by drug spraying, which can be killed with 50% malathion emulsion 1000-l500. After eliminating aphids, we also need to do a good job of prevention, which needs to start with daily maintenance such as light and humidity, so that a suitable environment can reduce the probability of aphids.

2. Red spider

Red spider belongs to mites, it is usually red, with black spots on both sides of the back, when it appears on the fragrant snowball, it will suck the sap inside the plant tissue, causing the leaves to wither and yellow, which usually occurs from June to July. It will have a very important impact on the flowering of fragrant snowballs.

It usually hides on the back of the leaves, and its size is small and not easy to detect, but we can check from the changes in the color of the leaves. Once we find that the leaves are faded and yellowed, we can check the leaves and find that the red spider removes the injured leaves in time. Then spray 2000 times of 15% acaridin EC.

3. Root rot

The affected part is the root, and a tumor mass will appear on the root, but the symptom is mainly manifested in the slow growth of the plant. During the peak growth period from April to May, the leaves appear yellowing and withering. At this time, we need to observe the leaves of the plant and see if the roots are damaged.

Root rot is mainly caused by germs, but the real reason is that the soil used to grow fragrant snowballs is unhealthy. It contains pathogens that can cause fragrant snowballs to infect root rot. When treated, the roots can be soaked with 1000 times of streptomycin. Prevention requires the use of healthy soil.

Diseases and insect pests mainly prevented by seedlings

I. aphids

Aphids are very common on seedlings in this area, and their hosts are mainly big-leaf yellow poplar, red-leaf plum, peach, begonia, pyracantha, crape myrtle, rose, oleander and so on. Its harm not only causes leaf shrinkage and poor growth, but also easily leads to seedling disease. April is the spring shoot period of seedlings, the branches and leaves are green, the nutrition is rich, the temperature is suitable, the breeding of aphids is very fast, and the occurrence range will expand rapidly. I hope all parts of the country will pay attention to investigation and timely prevention and control. Control agents: 10% imidacloprid or 10% Jinshi 1500 times solution.

Second, the yellow poplar silk borer

The yellow poplar silk wild borer overwinters as its larvae. when the weather turns warm, the insect will harm the melon seed, yellow poplar and sparrow tongue yellow poplar, seriously affect the growth of new buds, and even die. Prevention and control should be carried out at the beginning of the hazard, especially in the seriously harmful plots of the previous year. The agent can be sprayed with 2500 times of 40% toxic silk EC or 25% cypermethrin EC.

The insect is mainly harmful to Euonymus tomentosa, has a large food intake and likes to do harm to clusters, so it can be treated with insecticides to control Chilo suppressalis.

Scale insects

The velvet scale on purple micro, the shield scale, blowing cotton scale, holly and camellia on purple micro scale, yellow poplar, sweet-scented osmanthus, etc., all hatched in April. Please strengthen the investigation and find that the harmful seedlings can be sprayed with 28% scale bao EC 1200 times or 40% Lesben EC 800 times plus 10% imidacloprid 1000 times.

4. Grub (Bombyx mori)

The grub overwintered in the soil, and when the soil temperature rose from March to April, the grub began to move and feed on seeds, seedlings and roots, which was the main underground pest in the nursery. The control agent can be sprayed with 10% Yifengshou granule 0.5 kg / mu, and the seedlings in the nylon shed should not be used to prevent drug damage. 1000 times liquid of acephate can be used.

5. Powdery mildew

Powdery mildew is the main disease on seedlings, and there are many susceptible tree species, such as crape myrtle, peach, rose, narrow leaf, big leaf yellow poplar and so on. With the increase of temperature and rainfall, it will occur one after another. The prevention and control of powdery mildew should be based on the principle of "prevention first and comprehensive prevention". Seedlings with serious disease in the past can be sprayed with M45 Dasheng 600x liquid when the new buds grow to a certain extent; for seedlings that have already occurred, it is necessary to seize the initial stage of the disease. use 15% vermicellin wet powder 1500 times, or 50% Cuibei dry suspension 4000 times, 40% Fuxing EC 8000 times control, serious condition once every 15 days or so.

6. Longicorn beetles

Longicorn beetle is a hidden pest with serious harm and great difficulty in control. In recent years, the occurrence of longicorn beetles, such as longicorn beetles and red-necked longicorn beetles, which mainly occurred on the seedlings in our region, overwintered as larvae in the trunk of the host tree. After April, they began to rise to feed, especially poplar, willow, elm, disease-free, Koelreuteria, peach, plum and other tree species, once fresh insect dung appeared on the ground around the trunk. The results show that the overwintering larvae have begun to feed and should be killed with steel wire in time, or with 40% poisonous filament or 80% dichlorvos EC 30 times.

Leaf mites, crown net bugs

According to the investigation in late March, leaf mites on some seedlings have already begun their activities, and the damage is expected to intensify in April. The medicament control can be sprayed with 2500 times EC. Crown net bugs that harm rhododendron, pyracantha, peach, plum, scarlet, cherry blossom and so on are expected to be harmful from late April. Drug control can choose 1.8% avermectin 2500 times, or 2.5% permethrin 3000 times solution, spray should focus on the back of the leaf.

What are the factors that affect flower seed emergence? Seed China believes that improving the emergence rate of flower seeds is a highly technical work. In order to improve the emergence rate, we should first understand the reasons that affect the emergence rate in order to deal with it reasonably.

There are quality problems in seeds.

At present, there are more flower seeds on the market, florists should pay attention to the production date and shelf life marked on the bags when buying domestic or imported seeds. Do not buy seeds that are not marked

Because most of the expired seeds have lost their vitality, they will not germinate and emerge. In addition, when buying seeds, florists should have a basic understanding of them, such as whether the seeds they buy are 2012 flowers, perennial flowers, spring flowers or autumn flowers. Generally speaking, seeds sown in spring generally blossom in summer and autumn; seeds sown in autumn generally blossom in spring and summer (except woody flowers). If the sowing date is reversed, and there is no certain anti-season cultivation conditions, it will be difficult to achieve the expected flowering. You should be more cautious in buying flower varieties that have never been raised before.

Seed treatment is not in place.

Different seed treatment methods should be used for different flower seeds. Seeds that are easy to germinate can be soaked, such as a string of red seeds soaked in warm water at room temperature of 40 ℃ for one day and night, rinsed and then sown. Hard seeds, such as asparagus, peony, Jiulixiang, Baizhihong, Daphne, etc., should be soaked in 40 ℃ of hot water for about 48 hours before sowing in basin soil. After 20 ~ 30 days, they can sprout and grow. For Pearl Plum and Bauhinia which have a short dormant period and are easy to germinate, the seeds can be sowed directly in 40 ℃ ~ 60 ℃ warm water for 24 ~ 48 hours. Some flower seeds need to be treated at low temperature for a certain period of time in order to promote post-ripening and break the dormancy of seed embryos to germinate, such as cloves, wintersweet and some herbaceous flowers sown in autumn. Some flowers have the characteristics of double dormancy of radicle and Hypocotyl, that is, the radicle needs to go through a high temperature stage of 25 ℃ ~ 32 ℃ for 1 to 2 months or more in order to break dormancy, such as tassel, pod fan, peony seeds.

Ignore the suitable temperature for seed germination

The germination of dry seeds must not only have certain moisture conditions, but also have a certain suitable temperature. For example, the suitable temperature for germination of Cruciferae Snowball must be 5 ℃ ~ 20 ℃, and that of Gerbera must be at

20 ℃ ~ 25 ℃, the suitable temperature for primrose germination must be in the range of 15 ℃ ~ 18 ℃. Too high or too low temperature will affect the emergence rate of flowers, and even cause the occurrence of mildew and rot of seeds, which will greatly reduce the germination rate and seedling rate.

The sowing time is unreasonable

Seeds with large grains, solid skins or oily seeds, such as rose, rose, pomegranate, kumquat, magnolia and other flowers, are suitable for sowing in autumn. Seeds with small grains and thin skin, such as chrysanthemum, asparagus, impatiens, hundred-day red, Lingxiao and other flowers, are suitable for sowing in late spring. Seeds that need high temperature to germinate should be sown in time after maturity, such as cyclamen, chrysanthemum, Zhu Dinghong and other flowers should be sown in early summer.

There is a problem with the sowing quality.

There are two forms of flower sowing: open field sowing and pot sowing. No matter which method requires loose and ventilated soil, fine particles and good drainage, it is better to use fertile soil rich in humus nutrients and moderate acid and alkali, which is beneficial to seed emergence. The specific sowing methods include sowing, strip sowing and hole sowing. Sufficient water should be watered before sowing and covered with plastic film after sowing to prevent the dry soil from affecting seed germination and emergence. The sowing depth is generally 2.5 times of the grain diameter of flowers. Small cockscomb, August chrysanthemum, four seasons begonia, melon leaf chrysanthemum and other seeds, mix well with fine sand and seeds before sowing. During the germination of seeds after sowing, attention should be paid to spraying water to keep moisture, but not too much to prevent rotting of seeds and fibrous roots of seedlings.

Ignore the influence of light

After sowing flower seeds, proper light can increase soil temperature and induce seed germination, especially for seeds to break through the seed coat, root and bud, which not only affects the emergence rate of seeds, but also directly related to the growth of good seedlings and strong seedlings. Therefore, from sowing to transplanting stage, we should try our best to meet the needs of light for flower growth, and the light intensity is a gradual transition from dark to weak light and then to natural light.

Key points of technical management of ground cover plant maintenance

At present, ground cover plant is an important part of urban green space, and its application has changed from evergreen type to flower-watching type. As the characteristics of ground cover plants belong to large area cultivation, under normal circumstances, it is not allowed and impossible to achieve fine management and maintenance, and can only be based on the principle of extensive management. The management and maintenance of ground cover plants mainly focus on the following points:

1. Prevent soil erosion

The soil of the planting site must be loose, fertile and well drained. In general, it should be checked 1-2 times a year, especially after a rainstorm or typhoon. For places with serious soil erosion, immediate measures should be taken to plug loopholes and cover soil in time, replant and restore the landscape. Otherwise, the loss will continue to expand, creating a situation that is difficult to clean up.

2. Actively cultivate fertility

During the growing period of ground cover plants, fertility should be replenished in time according to the needs of all kinds of plants, especially for some flowering ground cover plants. Fertilization is mainly based on the application of thin inorganic fertilizers such as ammonium sulfate, urea, calcium superphosphate, potassium chloride and so on. Sometimes in early spring and late autumn or before and after the plant dormancy period, the spreading method, combined with soil mulching, is beneficial to overwintering plants, and can be adjusted to local conditions, making full use of compost, cake fertilizer, river mud and other organic fertilizer sources.

3. Timely drought resistance and watering

In general, ground cover plants select drought-resistant varieties with strong adaptability, which do not need watering, but when there is continuous drought and no rain, in order to prevent ground cover plants from serious drought, watering should be carried out.

4. Pest control

Most ground cover plant varieties have strong resistance to diseases and insect pests, but sometimes diseases and insect pests occur due to poor drainage or improper fertilization and other reasons. When plants are planted in a large area, the diseases most likely to occur are Rhizoctonia solani, Botrytis cinerea, white silk disease, etc., which can wither the land, so spraying measures should be taken to prevent it from spreading and expanding. Insect pests are most likely to occur in Spodoptera litura, grubs, aphids, bridge insects and so on.

5. Trim and smooth at the right time

General low type varieties do not need regular pruning, mainly extensive management. However, due to the introduction of a large number of flowering ground cover plants in recent years, a few with residual flowers or tall flowers must be properly lowered after flowering, or combined with seed harvesting and proper pruning.

6. Update and recovery

In the management and maintenance of ground cover plants, it is often due to a variety of unfavorable factors that the ground cover appears premature senescence. According to different conditions, piercing the topsoil to make the root soil loose and breathable, and at the same time strengthen fertilization and watering, which is conducive to renewal and recovery. For some perennial ground covers of ornamental flowers, the roots must be replanted every five or six years, otherwise it will also cause natural decline. When replanting ramet, the senile plants and diseased plants should be removed, and the strong ones should be selected and replanted.

7. Adjust the ground cover community

The cultivation period of the ground cover is longer than that of other plants, but it is not fixed after a single planting. In addition to some varieties with their own renewal ability, it is generally necessary to make appropriate adjustments from the aspects of ornamental effect, covering effect and so on. When adjusting, pay attention to the coordination of flowers and colors, be eye-catching, and avoid weeds. If some ornamental quilts are properly planted on the green grass, the colors are easy to coordinate, such as low purple flowers, white clover and yellow dandelions. If you plant snow-white fragrant snowballs and sunflowers on the edge of the road or lawn, it will be more elegant, eye-catching and luxurious.