The prevention and control of diseases and insect pests of medicinal flowers and the main points of sowing flowers in different seasons

For the prevention and control of diseases and insect pests in medicinal flowers, we must first understand the causes of the disease and the types of diseases and insect pests, grasp the law of the occurrence and development of diseases and insect pests, and implement the policy of "prevention first, comprehensive prevention and control". Secondly, comprehensive consideration should be given to increasing the output and quality of medicinal flowers and reducing environmental pollution. In particular, it is necessary to prevent toxic residues from harming the body. After mastering these principles, the following prevention and control methods can be applied:

1. Plant quarantine is a method to prevent and control medicinal flower diseases and insect pests according to a series of quarantine laws and measures formulated by the state in order to prevent the import of new dangerous diseases and insect pests from other countries or other epidemic areas and to limit the spread of local diseases and insect pests.

Therefore, the quarantine procedures should be strictly carried out in the introduction of medicinal flowers and the transportation of seedlings.

two。 Agricultural prevention and control is the comprehensive use of cultivation and management technical measures to control and eliminate diseases and insect pests, which is called agricultural prevention and control law. The following methods are commonly used:

The main results are as follows: (1) the resistance of different varieties of medicinal flowers to diseases and insect pests is very different, so the selection of high-quality and high-yield varieties of medicinal flowers with disease resistance is an economical and effective measure to control diseases and insect pests. If there are thorns, safflower is more resistant to anthracnose than safflower without thorns. Single plant resistant to diseases and insect pests should also be selected in the same variety. In addition, we should also choose disease-free or less disease types, in order to reduce the source of disease.

(2) reasonable rotation of different medicinal flowers has different diseases and insect pests, and all kinds of diseases and insect pests have a certain parasitic range.

Therefore, different medicinal flowers or crops are often rotated in an area or a piece of land, so that those diseases and insects that are not suitable for the new environment and food will gradually decrease and naturally die out; good results can also be achieved for soil-borne diseases and insect pests as well as monophagous and oligophagous pests. At the same time, crop rotation can also improve the soil, promote the growth and development of medicinal flowers, and enhance the effect of crop rotation.

The resistance to diseases and insect pests, such as the general serious root rot disease of medicinal flowers and Gramineae rotation for more than 4 years, can reduce the occurrence of root rot and white silk disease.

(3) regulating the sowing date of some diseases and insect pests is often closely related to the phenological phase of a certain growth and development stage of medicinal flowers. If we try to avoid the danger period of a large number of diseases and insect pests in this stage of growth and development, we can reduce or reduce the harm of diseases and insect pests, such as early sowing of safflower can avoid the harm of anthracnose and safflower fruit fly, Coix is suitable for late sowing, it can reduce the occurrence of powdery mildew, and summer sowing of hemerocallis can avoid the harm of seedling pests in spring. Therefore, adjusting the sowing date is an effective means to avoid disease and prevent pests.

(4) Deep ploughing and careful cultivation can not only promote the root development of medicinal flowers, enhance the ability of absorbing fertilizer, make them grow strong, but also directly kill diseases and insect pests.

(5) the disease and insect pests in the clean countryside harm residual plants and withered branches, fallen leaves and weeds in the field, which are often hidden and overwintering places for diseases and insect pests, and become the source of diseases and insect pests in the coming year. Therefore, the fallen leaves of diseased plants are collected and burned and the countryside is cleaned, which can reduce the occurrence of diseases and insect pests.

(6) to strengthen the field management, including reasonable fertilization, timely drainage and irrigation and weeding and other technical measures, through fine field management to achieve the effect of pest control.

3. Biological control is called biological control by using some beneficial organisms in nature to eliminate or restrain certain diseases and insect pests.

At present, biological control is mainly carried out by means of pest control, bacterial control, bacterial control and bird control. For example, the use of walking insects, aphid-eating ladybugs, aphid-eating gadflies, flies and other predatory beneficial insects to control aphids, and the use of cocoon wasps, Trichogramma and other parasitic bacteria and fungi to control cabbage green insects, heart-eating insects, grubs, beetles, ground tigers and other pests; using antibiotics such as Chunreomycin, "5406" and internal therapies to control Rhizopus and anthrax. Biological control is an important aspect of integrated control, which has the advantages of harmless to human, animal and plant, safe use, no residual poison, no environmental pollution, long-lasting effect, prevention and so on.

4. Physical and mechanical control according to the living habits of diseases and insect pests and the law of the occurrence of diseases and insect pests, the use of temperature, light and instruments and other physical machinery to eliminate diseases and insect pests, called physical and mechanical prevention and control method. For example, diseases and insects with low activity, concentrated harm, or false death should be hunted and killed artificially; for phototactic Lepidoptera and some underground pests, moth trapping lights or black lights should be used to trap and kill; high temperature and low temperature methods should be used to control warehouse pests. According to the weight of seeds with diseases and insect pests is lighter than healthy seeds, seeds with diseases and insect pests can be eliminated by wind selection and water separation. In recent years, new physical technologies such as ultrasound and radiation have been used to directly kill germs and pests.

5. Chemical control the method of applying chemical pesticides to control diseases and insect pests is called chemical control. It has the characteristics of fast effect, good effect, easy to use, can eliminate or control a large number of diseases and insect pests in a short period of time, and is relatively small by regional and seasonal restrictions, so it is a commonly used method to control diseases and insect pests. However, it also has some disadvantages, such as long-term use of pesticides, pathogens are easy to produce drug resistance, while harming some beneficial organisms, which is not conducive to biological control. In addition, there are some shortcomings, such as pesticide residues, environmental pollution, affecting the quality of medicinal flowers and so on.

At present, the commonly used chemical pesticides can be divided into insecticides and fungicides according to their toxicity to diseases and insect pests, as well as herbicides and so on. Insecticides can be divided into stomach poisons (such as lead arsenate, trichlorfon, etc.), contact insecticides (such as pyrethrum), internal inhalers (such as dimethoate, "1059", "1605', etc.), fumigants (dichlorvos, chloropicrin, etc.). At present, most fungicides are protective agents (such as Bordeaux solution, Dyson zinc, etc.). Protective agents need to be applied before the onset of the disease of medicinal flowers, and then reused every time they reach the efficacy period. Fungicides also have therapeutic agents (such as stone-sulfur mixture, bacilli, etc.) and internal inhalers (such as dioxin, dimethazone, antibiotics, etc.).

When the above chemicals are used, the methods of spraying, powder spraying, fumigation, seed mixing, seed soaking, smearing, soil treatment and making poison valley, poison bait and poison soil can be used to control diseases and pests.

In the use of chemicals, attention should be paid to: understanding the medicinal properties, prescribing the right medicine to the case, seizing the opportunity, timely spraying, mastering technology, ensuring efficacy, paying attention to safety, and avoiding drug damage and human and animal poisoning. In recent years, with the development of atomic physics, ionizing radiation has been used to kill pests directly. In addition, laser can also be used to control pests.