1. Morphological characteristics
The individual development of Aphid can be divided into three stages: egg, nymph and adult mite.
① eggs
Round. Female mites can lay two kinds of eggs, one is limb eggs, and the other is limb eggs with a size of 0.65 mm χ 45 mm, which are small in size and gradually turn yellow, dry and die. Female mites began to lay limb eggs 60 hours after the larvae were covered. The egg is white, and the embryo can be seen in the thin egg membrane, which looks like a clenched fist.
② Ruo mite
If mites are divided into prophase and anaphase. In the early stage, the mite is oval, white and transparent, with 4 pairs of feet, the size is 0.7 mm × 0.8 mm, the abdomen has anal plate, and the trachea is immature. The feet are angular and there is a small sucker in the tarsal joint. In the prophase of male, the nymph size is 0. 62.74 mm× 0.58 ~ 0.69 mm, the shape of anal plate is hard, and the trachea and feet are the same as those of female mites. In the late female stage, if the mite body is oval, the size is 0.9 ~1.1mm×1. L4 ~ 1.6mm, the backboard is obviously ossified. In the late male stage, if the mite is round, its size is 0.74 ~ 0.88 mm× 0.7 ~ 0.8 mm, and it has four pairs of feet. According to the distribution of bristles, male and female mites can be distinguished. Female mites have many bristles, while male bristles are only distributed in the anal area.
③ Adult mites
Female adult mite, brown, the body is covered by the whole keratinized backboard, and there are reticular patterns on the backboard. Some male mites have black spots on their backboards, which are covered with dense bristles. Their bodies are oval, with the size of 1.44 mm× 1.73 mm, and their ventral surfaces are composed of chest plate, reproductive plate, femoral web, ventral side plate and anal plate. Mouth is located under the body and consists of the whole limb and foot. The valve is outside the third and fourth pairs of foot base joints, and the foot is thick and short, consisting of six joints. Male adult mite, ovoid, light yellow, with few bones, the size is 0.89 mm× 0.73 mm, the backboard and webbed plate are healed, the tentacles have movable limbs and become concave appendages, and the end is spoon-shaped and small, which is suitable for transmitting semen. Below the mouthparts are the sex organs, and the bone plate on the ventral surface is not obvious except the anal plate. There are more bristles in the anal area in front of the abdomen and thicker bristles on the back of the body.
2. Biological characteristics
① Reproductive characteristics
1 female mites can lay 1 ~ 7 eggs, and most of them lay 2 ~ 5 eggs. 94.8% of the wasp mites entering the nest room have oviposition ability, and only 5.2% have no oviposition ability. It was found that the female mites mated with the male mites 48 hours after entering the larval chamber covered by bees, and their abdomen swelled and their movements were slow. After 60 ~ 64 hours, they began to look for spawning sites. Although the oviposition ability is very strong, the survival rate is very low, only 35.8% can form new female mites, and 3.8% die. Among them, 17% formed new male mites, 9.4% died and 33% could not develop into adults. Male mites will not die immediately after mating with female mites. Most male mites die after the young bees leave the house, while female mites parasitize the bees or move to new larval houses when the young bees leave the house. Experiments show that all the big wasp mites that sneak into worker bees' nests are female, and only one generation is bred in a closed room, and there is no generation overlap. When a pregnant female lays 1 egg, she will develop into a female in most cases. If they lay more than two eggs, one of them will develop into a male. The sex ratio of female and male mites is 1.42: 1.
② Life cycle
The life cycle of Aphida wasp is 20-24 hours, 52-58 hours in the early stage and 80-86 hours in the late stage. The life cycle of male mites is 6.5 days and that of female mites is 7 days.
③ Parasitic habit
The parasitism of bee mites can be divided into two stages: free parasitism and closed indoor reproduction. In the stage of free parasitism, it parasitizes between the chest and abdomen of worker bees and drones. Generally speaking, 1 ~ 2 female mites are parasitic on 1 worker bee, and there are as many as 7 male mites. In the breeding stage in the closed nest room, the worker bee larval room is usually parasitic with 1 ~ 3, while the drone larval room can be as high as 20 ~ 30. The reason is:
1. The larval chamber of drone is concentrated on the edge of nest and spleen, and the temperature is low, which is suitable for parasitic reproduction of giant bee mites.
The second is the attraction of hormones secreted during the development of drone larvae.
Thirdly, the development period of drone larvae is longer than that of worker bees 12 hours, and worker bees feed drone larvae more times, which increases the chance of bee mites sneaking in.
④ the influence of temperature
The optimum temperature for aphid development is 32 ~ 35℃. It can be frozen at 10 ~ 13℃. 18 ~ 20℃ began to move, coma at 42℃, and death at 43 ~ 45℃. According to the observation of indoor artificial culture, the longest life span of giant bee mite is 54 days, and the average life span of adult mite in breeding period is 43 ~ 45 days. In Beijing, the life span of bee mites in overwintering bees is more than 3 months. However, in the cold areas of northeast and northwest, the parasitic life of this mite on adult bees can reach more than 6 months.
3. The influence of the big bee mite on bees.
There are many deformed young bees in front of the hive, their wings can't be stretched or broken, the worker bees become smaller, the male bees' sexual function declines, and the queen bee's life span is shortened. When the larva produces eye pigment, if it is parasitized by 2 ~ 3 bee mites, its weight will be reduced by 15 ~ 20%. When bee mites suck the body fluids of bees, their weight will be reduced by 0. 1 ~ 0.2% every 2 hours, and their flying ability will also be reduced. If the young bees parasitize the wasp mite 1 ~ 10 days after emergence, the life span of the bees will be shortened by 50%. In addition, bees injured by the big bee mite are easily invaded by bee paralysis virus and infected with paralysis disease because their bodies are punctured. After the bee was parasitized by the giant bee mite, it often twisted its body in an attempt to get rid of it, which led to Penangal's exhaustion and collapse. The developing bee colony is weakened by the parasitism of bee mites. Seriously damaged bees, larvae or pupae of all ages have died. The nest cover is irregular, the dead larvae have no certain shape, and the larvae rot; But it won't stick to the nest room and is easy to remove. When the dead pupa's head sticks out, the young bee can't get out. Parasitic bee mites can also be found on worker bees, drone larvae and pupae. If mites are not treated in time before the autumn breeding period of overwintering bees, bees will not be able to overwinter safely and cause serious losses.
4. The resistance of bees to mites (anti-mite)
Chinese bee is the original host of the big bee mite. In the long-term evolution process, Chinese bees have developed anti-mite, mainly because of its strong ability to eliminate bee mites. Experimental observation shows that Chinese bees use their front and rear feet to scrub the chest, abdomen or twist the lateral abdominal surface of the abdomen to remove mites from the body. The cleaning behavior is called self-cleaning. When the self-cleaning is unsuccessful, the bees immediately swing their bodies to make a cleaning dance, and the accompanying bees bite the bee mites with their upper jaws, hold them with their front feet, and pick them off or fall to the bottom of the hive. This action is called peer-to-peer cleanup behavior and is the main cleanup behavior. The phenomenon that bees remove mites in the pile is a minority, which is called collective mite removal behavior.
5. Diagnostic methods
① Symptom examination
According to the dead bees in front of the nest and the death status of larvae and pupae on the nest spleen. If many young bees with broken wings and feet are found crawling in front of the nest, dead pupae are dragged out by worker bees, dead and black larvae and pupae appear on the spleen of the nest, and large bee mites are attached to the pupae, it can be judged as the harm of large bee mites.
② Inspection of mite peak
Spleen with bee larvae was extracted from the bee colony, and 50 ~ 100 worker bees were randomly selected to check whether there were bee mites parasitized in the thoracic and abdominal segments, and the parasitism rate was calculated according to the ratio of the number of bee mites to the number of bees detected. Open 50 sealed nests with tweezers, carefully check whether there are bees and bees mites in the nests with a magnifying glass, and calculate the parasitism rate according to the number of bees and bees. When there are drones in the bee colony in spring or autumn, it can also be used as an index for timely prevention and control, checking the covered drone room and calculating the parasitism rate of bee mites.
6. Occurrence regularity
The growth and decline of bee mites are closely related to the colony potential, air temperature, honey source and spawning time of queen bees. In Beijing, the queen bee began to lay eggs in spring, and when the bee colony appeared to cover the spleen, the bee mites began to breed. In summer, the honey powder source is sufficient, the queen bee lays eggs vigorously, and the bee colony enters the peak of reproduction. At this time, the parasitism rate of bee mites remained relatively stable. In autumn, the outside temperature is low, the honey source is lacking, and the population declines, but the bee mites continue to breed and concentrate on a few spleen-covered and bees, and the parasitism rate of bee mites rises sharply. In autumn or early winter, when the queen bee stops laying eggs and there is no spleen in the bee colony, the bee mites stop breeding and overwinter on the bee body in the form of adult mites. So you can see big bee mites in the bee colony all year round.
7. Prevention and control methods
① heat treatment
A good acaricidal effect can be obtained by shaking off bees with a metal net cage, heating in a special way and continuously rotating the net cage for 5 minutes at 465438 0℃. This physical method is more beneficial than chemical drugs to kill mites. But it is inconvenient in practical application and cannot be popularized in beekeeping production. ② Application of biological characteristics
Taking advantage of the characteristics that giant bee mites like drone rooms, a special drone room foundation was made to induce queen bees to lay drone eggs and hatch into drone larvae. After bee mites gather in the unmanned computer room, they are extracted and burned. This method can reduce the number of bee mites by 20-30%. In addition, drone nests are often cut off, and drone larvae and bee mites are removed to reduce the parasitic rate.
③ Drug treatment of mites.
According to the characteristics of bee mites parasitic on bees and breeding in closed rooms, in order to achieve a thorough control effect, it is best to apply pesticides at a favorable time when the queen bee has not laid eggs in early spring and stopped laying eggs in late autumn, and there is no cover on the spleen of the bee colony. There are many kinds of anti-mite drugs. This paper introduces the commonly used effective anti-mite drugs in China for selection in prevention and control.
(1) Fast acaricide: It is a new acaricide. Safe for bees. The experimental results showed that the lethal concentration was 205ppm, which was highly toxic to bee mites. All the bees sprayed with 25ppm mites were shot down within 4 hours, and the acaricidal effect reached 100%. The control concentration of bee colony is 0.65,438+0%, that is, each ampoule is diluted with 500 ml of water. In the non-honey-collecting period, bees spray after returning to their nests. Take medicine every other day 1 time, usually twice. If it is not thorough, you can use 1 time after 1 week.
(2) A new non-amidine acaricide: Diptera 1. It is safe for bees, the lethal concentration is 2 18.6ppm, and it is highly toxic to the big bee mite. When 25ppm bees are used to spray mites, the acaricidal effect is 100%. When the concentration of 0. 1.25% is used in the bee colony, that is, 0.5 ml of medicine per ampoule is diluted with 40 ml of water, and the bee body is sprayed evenly at night, once a week 1 time, twice in a row, the acaricidal effect can reach 1%. This medicine can not only kill mites on bees, but also kill bees in nests.
(3) "Mipopu" high-efficiency acaricide tablet: This drug is a new acaricide successfully developed by Bee Research Institute. It has a high-efficiency killing effect on the big bee mite, is simple and easy to use, kills mites quickly and permanently, is safe to bees and has no residue. The application method is as follows: fix the tablets between the second bee lanes of the bee colony with thumbtacks, with 2 pieces of strong bee colony hanging obliquely, and 2 pieces of weak bee colony 1 tablet, with 3 weeks as a course of treatment. Compared with the existing drugs, this new acaricide has the following advantages:
First of all, the acaricide is attached to the carrier, which is not in direct contact with bee products and has no pollution to bee products.
Secondly, it is safe for bees, and has a good killing effect on the big bee mite, and the drug effect lasts for a long time. It can kill mites that leave home one after another, and the control effect is as high as 100%.
Third, it is convenient to use, saving labor and time. When it is necessary to control mites, the tablets can be hung on the nest and spleen together with the bee colony inspection, and there is no need to unpack them separately. Compared with other spraying drugs, the work efficiency can be improved by 5- 10 times. The drug has obtained the national patent, and it is the most ideal drug for controlling bee mites in China at present. In practice, it has been welcomed and praised by the majority of beekeepers, and has been widely popularized and applied throughout the country. The above three drugs are all produced by bee pharmaceutical factory of bee research institute, which supplies the needs of the whole country.