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As a type of special pesticide, the biological pesticide, compared with the chemical pesticide, has higher technical requirements for use and it shall be emphasized to see the content of label clearly in the actual purchase and use process and proper use methods and techniques shall be adopted in accordance with the specific features of different kinds of biological pesticides to ensure that the effect of biological pesticide is fully developed.

I. Microbial pesticides

1. Master the temperature. The activity of microbial pesticide is directly related to the temperature and the suitable temperature for usage environment shall be between 15℃ and 30℃. The reproduction speed of the sprayed biological pesticide in the pests is slow when the temperature is below the suitable temperature and it is difficult to develop the effect, which leads to a poor effect of the product. In general, the control effect of microbial pesticide in 20～30℃ condition is 1～2 times higher than that in 10～15℃ condition.

2. Seize the humidity. The activity of microbial pesticide is closely related to the humidity. The higher the humidity of farmland is, the more obvious the pesticide effect is, and the situation is especially true for powdery microbial pesticides. It is recommended to apply the pesticide in the morning and evening when the dew has not been dried to make the microbes reproduce quickly and achieve a better control effect.

3. Avoid strong light. The ultraviolet radiation has a lethal killing effect on the microbial pesticides and the microbe mortality can be over 50% and 80% when the microbes are directly exposed to the sunlight for 30min and 60min. It is recommended to apply the pesticide on cloudy days or in the evening.

4. Avoid rain wash. The light rain after spraying is conducive to the reproduction of the active tissues in the microbial pesticide and won’t affect the pesticide effect. However, the rainstorm will wash away the pesticide solution sprayed on the crops and affect the control effect. The pesticide application shall be carried out in due time according to local weather forecast and heavy rain and rainstorm shall be avoided to ensure the insecticidal effect.

In addition, the microbial pesticides of virus type have a strong specificity and each of them generally only works on one kind of pest and doesn’t work on other pests. For example, the plutella xylostella granulovirus can only be used for plutella xylostella control. The insect pest condition of the farmland shall be investigated before use of pesticide and the control period shall be reasonably arranged in accordance with the insect pest condition and the pesticide shall be applied in due time.

II. Botanical pesticides

The control performances of botanical pesticides and chemical pesticides on plant diseases and insect pests of crops are similar to those of human after taking Chinese traditional medicine and western medicine. The following key points shall be mastered in case of using botanical pesticides:

1. Prevention first. The pesticides shall be applied in time when plant diseases and insect pests are found and it is not suitable to carry out the control procedure when there are large-scale plant diseases and insect pests. The effect of botanical pesticide is generally slower than that of chemical pesticide and the plant diseases and insect pests will not healed immediately after pesticide application. The application time shall be 2-3 days earlier than that of chemical pesticide and its control effect can be observed generally 2-3 days after the pesticide application.

2. Combine with other means. In case of serious plant diseases and insect pests, the chemical pesticides shall be used first to reduce the number of plant diseases and insect pests as soon as possible and control the spreading trend, and then botanical pesticides shall be used to carry out the integrated management.

3. Avoid pesticide application on rainy days. The botanical pesticides are not resistant to rain wash and a supplemental application shall be carried out in case of a rain after pesticide application.

III. Mineral pesticides

The currently common mineral pesticides include mineral oil, sulfur, etc. The following points shall be paid attention to when the mineral pesticides are used:

1. Spray after uniform mixing. It is recommended to adopt the secondary dilution method and the sprayer shall be kept vibrating and shaking to ensure that the pesticide solution is uniform all the time.

2. Spray uniformly with full coverage. Ensure that the crops and pests are in full contact with the pesticide to guarantee the effect.

3. Do not mix with other pesticides casually. This is to avoid damaging the emulsifying property, affecting the pesticide effect and even causing pesticide hazards.

IV. Biochemical pesticides

Biochemical pesticides refer to those that achieve the purpose of application by regulating or interfering with the actions of plants (or pests).

1. Sex attractants

The sex attractants cannot kill the pests directly and the main function is to trap and kill the pests and interfere with their normal mating to reduce the population density of pests and control the quick reproduction of insect pests. Therefore, the sex attractants cannot be relied on completely and generally shall be combined with other chemical control methods. For example, in case of using the lure of sex attractant for carposina niponensis walsingham, chemical agents may also be used in the appearing stage of eggs in the field in peak period.

(1) Use as soon as possible after unpacking. The sex attractant products are volatile and shall be stored in the refrigerator with a low temperature. Once unpacked, they shall be used as soon as possible.

(2) Avoid lure pollution. Due to the high sensibility of pheromone, the hands shall be washed before the installation of the lures for different kinds of pests to avoid pollution.

(3) Reasonably place the traps. The position, height and airflow of the traps will affect the trapping effect. For example, the suitable hanging height of the sex attractant for prodenia litura shall be 1-1.5m; This height may be properly reduced in accordance with the actual situation for use in protected areas; The height shall be 0.3-1m higher than the crops in the fields of brassica rapa chinensis; The traps may be hanged on the brackets in the fields of vegetables with high stalks; For the crops in greenhouses, the traps may be hanged on the frames.

(4) Replace the lures in time according to the specified time.

(5) Avoid endangering beneficial insects. The damages to beneficial insects shall be avoided in case of using pheromone. For example, the lures for lithocolletis ringoniella have a strong trapping and killing effect on osmia, so they should not be used in the flowering stage of fruit trees. When they are used for forecast, the osmia and bees should not be released in a place to breed in the flowering stage of the fruit trees in the observation nursery and adjacent orchards.

2. Plant growth regulators

(1) Select the right variety and use in due time. The effects of plant growth regulators vary with the crop varieties, growth and development periods and sites of action. The product of right variety shall be selected in accordance with the functions described in the product label and used in due time in strict accordance with the method of application stated in the label.

(2) Master the concentration. The principle of “the more, the better” is not applicable to plant growth regulators. The plant growth regulators shall be used in strict accordance with the concentration specified in the label, or the opposite effect will be achieved. For example, the auxin with a low concentration will promote the root growth while that with a high concentration will inhibit the growth.

(3) Prepare the pesticide solution as needed to avoid failure.

(4) Use uniformly. Some regulators like gibberellin rarely move in the plants and if half of one and the same fruit is treated, the treated part will be enlarged, leading to a malformed fruit. The spraying shall be uniform and meticulous in case of application.

(5) Do not substitute fertilizers with pesticides. Even the promoting regulators can only work in a condition of sufficient fertilizers.

V. Protein and oligosaccharide pesticides

This type of pesticides (e.g. amino-oligosaccharin, chitosan, lentinan, oligosaccharins, etc.) are plant inducers which have no killing effect on germs, but can induce the plant itself to respond to the attacks of invasive alien pests so as to improve the immunity and develop the disease resistance. The following points shall be paid attention to when the protein and oligosaccharide pesticides are used:

1. They shall be used before the occurrence of the plant disease or in the early stage of the plant disease. Curative bactericides shall be selected for symptomatic control when the plant disease is serious.

2. The pesticide solution shall be prepared as needed and shall not be stored for a long time.

3. They are not systemic pesticides and the spraying shall be uniform.

VI. Natural enemies

Currently trichogramma and anastatus japonicus are commonly used. Large-scale release in successive years is advocated, and the larger the area and the number of the release years is, the better the effect becomes. The following points shall be paid attention to when the natural enemies are used:

1. Reasonable storage. The bees shall be released in the morning after the tussah egg masses are obtained and shall not be stored for a long time. The bees shall not be released on the very day in case of extreme weather. The tussah egg masses shall be stored dispersedly in a cool and ventilated place and shall not be mixed with chemical pesticides.

2. Master the release time accurately. It is recommended to consider the insect pest condition to make the release time coincide with the oviposition time of pests.

3. Use separately with chemical pesticides. The chemical pesticides shall not be used within 5 days before the release and 20 days after the release.

VII. Antibiotic pesticides

The use methods of antibiotic pesticides (e.g. abamectin, spinosad, etc.) are the same as those of chemical pesticide. However, most of the antibiotic bactericides are unstable and shall not be stored for a long time, e.g. validamycin, which is easy to go mouldy. The pesticide solution shall be prepared as needed and shall not be stored. Some antibiotic pesticides like kasugamycin, validamycin, etc. shall not be mixed with alkaline pesticides and shall not be sprayed before and after lime and plant ash application on the crops.