I. Integrated pest management
There are many methods to control garden diseases and insect pests, and each method has its own advantages and limitations. Only taking one of these measures can not achieve the purpose of prevention and control, and sometimes it will cause other adverse reactions. Comprehensive management is a control scheme, which can control the occurrence of pests and diseases, avoid contradictions, give full play to the role of organic reconciliation, and keep the control system below the economic allowable level. The principles and methods of its comprehensive management are as follows:
1, economic, safe, simple and effective: this is the first problem to be considered when determining the comprehensive control plan, especially the safety problem, including plants, natural enemies, people and animals, so as to avoid drug damage and poisoning accidents. No matter what measures are taken, we should consider saving money, which is simple and effective.
2. Coordinate measures to reduce contradictions: chemical control often kills natural enemies, which requires the combination of chemical control and biological control to minimize the contradiction between them. When using chemical agents, we should consider the influence on natural enemies, choose agents that are harmless or less toxic to natural enemies, and organically combine chemical control and biological control by changing the application time and method to achieve the purpose of controlling pests and protecting natural enemies.
3. Complement each other and learn from each other's strengths: various prevention and control measures have their own advantages and disadvantages. Comprehensive management is to make all measures cooperate with each other and learn from each other's strengths, rather than simply "mixing". Chemical control has the advantages of quick response, good effect and high work efficiency, but the action of drugs is often limited to a short time, which can not control pests for a long time. Improper use can easily make bacteria and pests resistant, kill natural enemies and pollute the environment. Although the prevention and control of garden technical measures have preventive and long-term effects, they do not need additional investment, but they are powerless to the pests and diseases that have already occurred; Although biological control has many advantages, it may not be effective when pests and diseases break out. Therefore, various measures are not omnipotent and must be organically combined.
4. Try to treat both pests and diseases, and simplify the complexity: under natural circumstances, various pests and diseases often occur together. If we control them one by one, we will waste working time. Therefore, it is necessary to comprehensively consider chemical control, reasonably mix chemicals and choose the right time to achieve the purpose of controlling several pests and diseases at one time.
5. Have the overall concept: comprehensive management should proceed from the overall situation of the garden, consider the ecological environment, and give priority to prevention.
The second is the quarantine of garden plants.
Plant quarantine is one of the basic measures to control diseases, pests and weeds, and it is also a powerful guarantee to implement the policy of "prevention first and comprehensive management". Under natural conditions, although the distribution of diseases and pests can be spread by natural forces such as airflow and self-activity, and its distribution scope is constantly expanding, this ability is limited, and there are natural obstacles such as mountains, oceans and deserts, so the distribution of diseases and pests has certain geographical limitations. But once it is spread by human factors, it can be attached to plant products such as seeds, seedlings, scions and cuttings, and cross these natural barriers. When pathogens, pests and weeds leave their place of origin and arrive in a new area, some environmental factors that originally restricted the occurrence and development of pests and weeds are broken and the conditions are suitable, they will spread rapidly. For example, China's chrysanthemum white rust and cherry blossom bacterial nodules were introduced from Japan, which made many garden scenic spots difficult. Therefore, in order to prevent the spread of pests and weeds, plants must be quarantined.
Three, the garden prevention and control technical measures
The prevention and control of garden technical measures is to improve the cultivation technical measures, so that the environmental conditions are not conducive to the occurrence of pests and diseases, but conducive to the growth and development of garden plants, directly or indirectly eliminating or inhibiting the occurrence and harm of pests and diseases. This method does not need extra investment, and it has a preventive effect and can control pests and diseases for a long time, so it is the most basic control method. However, this measure also has some limitations, and other control measures must be relied on when pests and diseases occur.
1. Breeding disease-resistant varieties: Breeding disease-resistant varieties is an important link in pest control, and different flower and tree varieties have different degrees of harm to pests and diseases. At present, new varieties such as chrysanthemum, carnation and snapdragon have been cultivated, such as chrysanthemum varieties resistant to rust, chrysanthemum varieties resistant to aster blight, chrysanthemum varieties resistant to chrysanthemum leaf blight, poplar varieties resistant to black spot disease and longicorn.
2. Seedling raising measures: Many diseases and pests on garden plants are spread through asexual propagation materials such as seeds and seedlings. Therefore, through certain measures, the occurrence of such diseases and insect pests can be effectively controlled by cultivating strong seedlings without diseases and insect pests.
(1) Nursery without pests and diseases: Choose a place with loose soil, good drainage and ventilation, and no pests and diseases as the nursery. Attention should be paid to the disinfection of pot body and substrate in pot seedling raising. Such as chrysanthemum, carnation, etc., the survival rate of seedlings can be greatly improved by disinfecting the substrate in time or replacing the fresh substrate.
(2) Seed collection of disease-free plants (buds): Many diseases of garden plants are spread through seedlings, such as Cyclamen virus disease spread by seeds, chrysanthemum white rust spread by foot buds and so on. Only by collecting seeds (buds) from healthy mother plants can we get disease-free seedlings and avoid or alleviate the occurrence of such diseases.
(3) Virus-free seedling culture: Viral diseases are common and serious in garden plants, and many seedlings carry viruses. Virus-free treatment by tissue culture technology is very effective in preventing and treating viral diseases. Such as carnation virus-free seedlings and orchid virus-free seedlings, are very successful.
3. Cultivation measures
(1) Suitable planting in the right place: The so-called suitable planting in the right place means that the characteristics of garden plants are adapted to the environmental conditions of the planting place, so as to ensure the healthy growth of flowers and trees and enhance their ability to resist pests and diseases. Shade-tolerant plants such as spruce and Hosta should be planted in humid areas; Light-loving plants such as Chinese pine, pomegranate and Chinese rose should be planted in dry and sunny places.
(2) Reasonable collocation: When building a garden, avoid the collocation of trees and flowers with the same pests and diseases. For example, the close planting of begonia and cypress, peony and pine is easy to cause begonia rust and peony rust; Therefore, in landscape design, plant configuration should not only consider the beautification effect of the landscape, but also consider the problem of diseases. Continuous cropping will often aggravate the diseases of garden plants, such as carnations cultivated in greenhouse for many years, which will aggravate the occurrence of Fusarium wilt, and crop rotation can alleviate the diseases. The rotation time depends on the specific disease. The rotation of Celosia cristata brown spot disease will be effective for more than 2 years, while cyst nematode disease will take longer. Under normal circumstances, it is necessary to implement rotation for more than 3-4 years. Crop rotation is an ancient and effective disease prevention measure. Rotation plants must be non-host plants, which will lead to the death of bacteria in the soil because they can't find food, thus reducing the number of bacteria.
4. Management measures
(1) Pay attention to the sanitation in the garden: collect the residues of pests and diseases in the garden and the lawn hay layer in time, treat them, bury them deeply or burn them. During the growing season, the branches and leaves of pests and diseases should be removed in time, and the plants that died due to pests and diseases or other reasons should be removed. Artificial infection should be avoided in gardening operations, such as cutting flowers, picking hearts and weeding to prevent tools and human bodies from spreading germs. The soil and pots with pests and diseases in the greenhouse shall not be used again until they are properly treated. In soilless culture, the contaminated nutrient solution should be removed in time and cannot be used again.
(2) Strengthen fertilizer and water management: Reasonable fertilizer and water management can not only make plants grow healthily, but also enhance their ability to resist pests and diseases. Ornamental plants should use fully decomposed organic fertilizer without peculiar smell to avoid polluting the environment and affecting ornamental. When using inorganic fertilizers, we should pay attention to the coordination of nutrients such as nitrogen, phosphorus and potassium to prevent excessive fertilization or element deficiency. Watering method, watering amount and watering time all affect the occurrence of pests and diseases. Sprinkler irrigation and "watering" are often easy to cause diseases locally. It is best to use furrow irrigation, drip irrigation or watering along the edges of pots and pans. The amount of watering should be appropriate. Too much watering is easy to rot the roots, and too little watering is easy to lead to poor growth of flowers and trees due to lack of water, which may lead to various physiological diseases or aggravate infectious diseases. Drainage should be done in time in rainy season. It is best to choose sunny morning for watering, so as to reduce the humidity on the surface of leaves in time.
(3) Improving environmental conditions: Improving environmental conditions mainly refers to adjusting the temperature and humidity of cultivation sites, especially greenhouse plants, which should be ventilated frequently to reduce humidity, so as to reduce the occurrence of diseases such as gray mold and downy mildew. Planting density and potted flower placement density should be appropriate to facilitate ventilation and light transmission. The greenhouse temperature should be suitable in winter, and it should not be hot and cold. Lawn mowing height, times and time should also be reasonable, otherwise it will aggravate the occurrence of diseases.
(4) intertillage weeding: intertillage weeding can not only maintain soil fertility, reduce soil moisture evaporation, promote the robust growth of flowers and trees, improve stress resistance, but also remove the birthplaces and hidden places of many pests and diseases. Weeds such as purslane are intermediate hosts of gladiolus mosaic disease, and weeding can alleviate the disease. The larvae, pupae or eggs of pests, such as Eupolyphaga sinensis and Buxus buxus, live in shallow soil and can be exposed to the soil surface through intertillage, which is easy to kill.
(5) Turning over the soil and cultivating the soil: Combined with deep ploughing and fertilization, the overwintering bacteria and pests in the topsoil or deciduous layer can be deeply turned over. Parks, green spaces, nurseries and other places don't have flowers growing in winter, so it's best to turn them deep once, so that they can be buried deep underground and will not be harmful in the coming year. This method has a good effect on the control of flower Sclerotinia sclerotiorum. When ploughing, special attention should be paid to the soil layer under the crown and near the root neck of the park tree altar, so that the soil can reach a certain thickness, so that germs can not germinate and pests can not hatch or emerge.
5. Harvest and post-harvest management of organs such as bulbs.
Many flowers overwinter with bulbs, bulbs and other organs. In order to ensure the healthy storage of these organs, avoid watering a lot before harvesting to prevent storage rot caused by excessive water content. Harvest in sunny days, and minimize the wounds when digging; After digging out, carefully check, eliminate wounds, pests and rotten organs, disinfect and keep fresh when necessary, and then enter the cellar. The cesspit must be cleaned and disinfected in advance and ventilated. During storage, the temperature and humidity should be controlled. Generally, the pit temperature is about 5℃ and the relative humidity is below 70%. If conditions permit, it is best to put them into nylon net bags separately and hang them on the top of the wine cellar for storage.
Four, the physical and mechanical control of pests and diseases
The method of using various simple instruments and various physical factors to prevent and control pests and diseases is called physical and mechanical control. This method includes both ancient and simple artificial hunting and the application of new achievements in modern physics.
(1) Killing method: The method of catching or directly killing pests by manpower or various simple appliances is called killing method. Artificial killing is suitable for suspended animation, clustering or other pests that are obviously easy to catch. For example, most adults of scarab and weevil have suspended animation and can be knocked down to death in the morning or evening. When Ulmus pumila larvae mature, they cluster in bark cracks, tree scars or branches to pupate. At this time, they can be killed artificially. When pruning in winter, cut off the cocoon and bag of the yellow thorn moth and scrape off the egg pieces of the gypsy moth. In the growing season, the bracts of the leaf roller moth can be artificially clamped, the eggs removed and the adults of the longicorn beetle caught in combination with the daily management of the garden.
(2) Barrier method: According to the activity habits of pests, artificially set up various obstacles to cut off the invasion route of pests. This method is called obstacle method, also called obstacle method. For larvae who have the habit of going up and down trees, poison rings or rubber rings can be coated on the trunk to block and kill the larvae; In early spring, the plastic film ring is tied at the base of the trunk, which can effectively prevent locust and jujube inchworm from damaging trees or laying eggs; In greenhouses and various plastic greenhouses, 40-60 mesh gauze can be used to cover them, which can not only isolate the harm of aphids, leafhoppers, whiteflies, thrips, liriomyza sativae and other pests, but also effectively reduce the infection of virus diseases.
(3) Trapping and killing method: a method of trapping and killing pests by using the tropism of pests and manually setting instruments or bait. This method can also predict the occurrence dynamics of pests. For example, light trapping and killing is to trap and kill pests by using the light tropism of pests and artificially setting black light, frequency vibration insecticidal lamp and nano mercury lamp. Food trapping and killing is to use the chemotaxis of pests and mix appropriate amount of poison into the food that pests like to eat to trap and kill pests
(4) High temperature treatment: Any living thing, including plant pathogens and pests, has a certain tolerance to heat, and beyond the limit, the living thing will die. Pests and germs have poor tolerance to high temperature, so the method of killing germs or pests by raising the temperature is called high temperature treatment, also known as heat treatment. In the prevention and control of garden pests and diseases, there are two kinds of heat treatment: dry heat and wet heat.
Five, biological control of pests and diseases
Using organisms and their metabolites to control pests and diseases is called biological control. Biological control is characterized by safety to people, livestock and plants, no resistance to pests, wide sources of natural enemies and long-term inhibition. However, it is often limited to a certain insect state, with slow action, high cost and strict technical requirements for artificial culture and use. Therefore, it must be combined with other preventive measures to give full play to its due role. Biological control can be divided into: pest control, bacterial control, bird control and bacterial control.
Six, chemical control of pests and diseases
Chemical control refers to the use of various toxic chemicals to control pests and weeds and other harmful organisms. Chemical control has the advantages of high speed, high efficiency, simple use method, no geographical restriction and convenient large-scale mechanized operation. However, it also has some shortcomings, such as easily poisoning people and animals, polluting the environment, killing natural enemies, and causing secondary pests to be rampant again. Long-term use of the same pesticide will make some pests have different degrees of drug resistance. When pests and diseases occur, chemical control may be the only effective method. Chemical control will still occupy an important position for a long time to come. As for the shortage of chemical control, we can gradually solve it by developing pesticides with strong selectivity, high efficiency, low toxicity and low residue, changing the application mode and reducing the application times. At the same time, it should be combined with other control methods to give full play to the advantages of chemical control and reduce its toxic and side effects.