CATDOLL : CATDOLL: What is the cause of bee bites on honeycombs? How to treat and prevent them?

Prevention and control of nest moths, wax moths and wax moths Nest moths are the larvae of wax moths. Wax moths reproduce very quickly, and their eggs and larvae are very vigorous. Nest moths are active in the nest in late spring, summer and early autumn: they drill into the honeycomb, eat wax and honey, bore tunnels in the honeycomb, spin silk to make cocoons, and destroy the honeycomb and larvae. Italian bees are less affected, while Chinese bees often flee in their entire colony or gradually decline when attacked. Nest moths are one of the important enemies of honey bees. Newly made honeycombs should be allowed to breed several generations of bees in time to enhance the firmness of the honeycombs. When the honeycombs are not in use, they should be taken out of the beehive, and the propolis and beeswax on the frame beams should be scraped off and properly stored. Honeycombs that have just been shaken out of honey should be licked clean by the bees before they can be stored. The preserved honeycombs should be classified and stored according to full honeycombs, half honeycombs, pollen combs and empty combs. Empty combs should also be classified into new and old combs. Honeycombs should be stored in a dry, clean and airtight place. Prevent them from getting damp and moldy, as well as rodents and nest insects. To prevent nest insects, you can use the method of drug fumigation. 1. Carbon disulfide fumigation Stack 4-5 supers on the beehive, put 9 classified honeycombs in each box, and paste the box seams tightly. According to the amount of 3 ml to 5 ml per box, drop carbon disulfide on the filter paper, put it on the frame beam, cover the box cover and paste it tightly. Carbon disulfide is volatile, flammable and toxic at room temperature. When using it, avoid approaching fire sources or inhaling it into the human body. Carbon disulfide gas can kill the eggs, insects, pupae and adults of wax moths. After a thorough treatment, the problem can be solved. 2. Fumigation with glacial acetic acid 98% glacial acetic acid is highly lethal to the eggs and insects of wax moth, and can also kill spores of sporozoans and pathogens of amoebiasis. The dosage is 20 ml per box, and the usage is the same as above. 3. Sulfur fumigation Place an empty beehive with a window below, and place 4-5 layers of super boxes filled with honeycombs on top. Cover the box lid, paste the gaps tightly, put an iron sheet or tile through the window, put a few pieces of burning charcoal on it, and then sprinkle sulfur powder on it. The amount of sulfur powder used for each box of honeycombs is calculated at 5 grams. Sulfur dioxide produced by sulfur combustion cannot kill the eggs and pupae of wax moth, so it should be fumigated once every 12-15 days. After fumigation for 3 times, wax moth will be inactive below 10 degrees Celsius. In the northern region, honeycombs stored in winter do not need to be fumigated. Detailed prevention and control methods: Wax moth belongs to the order Lepidoptera, the family Pyralidae. The wax moths that harm the bee industry include the greater wax moth and the smaller wax moth. The harm of wax moth is mainly in their larval stage. Wax moth is a world pest, almost all over the beekeeping areas of the world. Its distribution is mainly limited by long-term cold. In high-altitude areas, wax moth does not occur or rarely occurs. In tropical and subtropical areas of Southeast Asia, wax moth damage is quite serious. The wax moth is the most important pest of bee products, causing serious losses to professional beekeepers around the world every year. There is no accurate estimate of the losses caused by wax moth to my country's beekeeping industry. They are particularly harmful to Chinese bees. The wax moth only feeds on honeycombs in the larval stage, harming the bee colony's lid, often causing "white-headed pupae" in the bee colony. In severe cases, white-headed pupae can reach more than 80% of the number of broods, and young bees that are forced to emerge will also be trapped in the nest due to the silk threads at the bottom of the room. ⒈ Prevention and control of wax moth ⑴ Morphological characteristics The eggs are short oval, 0.3-0.4mm long. The surface is not smooth. The egg color is pink at first, then turns milky white, pale, light yellow, and finally turns yellow-brown. The egg mass is a single layer, and the eggs are closely arranged. The larvae are milky white when they have just hatched, and turn gray and dark gray on the dorsal and ventral sides when they are slightly larger. The mature larvae can reach 28mm in length and weigh up to 240mg. The cocoon is usually naked and white, but some cocoons are also wrapped with black feces or moth debris. It is 12-20mm long and 5-7mm in diameter. It often cocoons on the bottom of the box and the sub-cover. The moth is silvery white in color, while the wax moth that feeds on the spleen is brown, dark gray or black. The adult female moth is large, with an average weight of 169mg and a body length of about 20nm. The labial palps extend forward, making the head hooked. The front 2/3 of the forewing is uniformly black, and the rear 1/3 has irregular light areas or black areas, dotted with black stripes and uneven spots. From the dorsal side, the chest and head are light in color. Male moths are smaller and lighter. Their body color is lighter than that of female moths. There is an obvious fan-shaped area on the outer edge of the top of the forewing, and the color is relatively lighter. The size and color of male and female moths vary greatly depending on the different larval food. ⑵ Life history and habits The life history of the wax moth is about 2 months, and can be as long as 6 months. For those with a longer period, dormancy occurs in the pre-pupa stage. In southern my country, 3 to 5 generations can occur, and there is a phenomenon of overlapping generations. After the adult moth emerges, it does not need food or water. It usually takes more than 5 hours to mate, and most of them start laying eggs after 4 to 10 days. The average egg-laying period is 3.4 days. The egg-laying amount is between 600 and 900, and some can lay 1,800 eggs. The egg-laying location is mostly in the gaps of the box wall. The life span of the moth is 3 to 15 days. Under the conditions of 30 to 32 degrees Celsius, most female moths that have mated will die within 7 days. At 35 degrees Celsius, the life span can reach 10 days. The lower the temperature, the longer the life span of the female moth. Male moths have a shorter lifespan. The average lifespan is about 5.5 days. Eggs develop faster at higher temperatures (29-35°C), and begin to hatch 3-5 days after they are laid. At 18°C, the incubation period of eggs can be extended to 30 days. Short-term exposure of eggs to extreme temperatures (above 46.1°C for 70 minutes, below 0°C for 270 minutes) will cause all eggs to die. Humidity also has a great impact on the hatching of eggs. When the relative humidity is between 25% and 35%, 1/3 of the eggs cannot hatch. A high humidity environment is more conducive to the hatching of eggs than a low humidity environment, shortening the egg period by 1-2 days and reducing the mortality rate by 14%. However, when the humidity is higher than 94%, the eggs are prone to mold; when it is lower than 50%, the eggs are prone to dryness, and the optimum humidity is between 60% and 85%. The larval stage is between 45 and 63 days, and the newly hatched larvae have the habit of eating the egg shells or being afraid of light. Young larvae will first feed on honey and pollen, then drill into the pollen from the outside of the cell wall, gradually extending tunnels to the middle of the honeycomb, where they continue to feed and grow, avoiding being removed by worker bees. The minimum temperature for larval development is 18°C, the optimum temperature is 30-35°C, and a relative humidity of 80% is conducive to larval development. Newly hatched larvae are lively and crawl quickly, and the activity of larvae after the second instar is significantly reduced. 1d larvae are small and not easily removed by worker bees, and the rate of their access to the honeycomb can be as high as 90%. The larval stage is generally 6-8 days, and the food intake is small for 1-2 days, which has little effect on the bees. 3-4 days have a large food intake and bore tunnels, which is the main insect stage that causes white-headed pupae. 5-6 days larvae are large, feed on the honeycomb, and are easily bitten by worker bees to the bottom of the box and no longer access the honeycomb. In the bee colony, the growth rate of wax moth larvae is extremely amazing. If the food and temperature conditions are suitable, the larvae will double their weight every day within the first 10 days after hatching. Such a fast growth rate means that once the bee colony is seriously weakened due to poisoning or other reasons, all the honeycombs in the colony can be destroyed by the larvae within 10 to 15 days. The developing larvae actually eat all the bee products in the bee colony, especially the black honeycombs. If the wax moth larvae lack food, the bee larvae will also be harmed. In warm seasons, many larvae often grow in pollen and wax scraps on the bottom of the beehive, but on processed beeswax, such as the new wax on the foundation or honey, the larvae cannot complete their life history. In the last day, the larvae will stop eating before cocooning and look for a suitable place to spin silk cocoons. Usually, mature larvae will drill into the cracks of the nest frame or the bottom of the box to gather and cocoon and pupate. There are dozens or hundreds of cocoons, and the cocoons are cylindrical. The larvae in the pre-pupa stage are significantly smaller and their body color darkens, from light yellow → light brown → brown → dark brown. Most pupae emerge after 5 pm, and the pupal period is shortest at 30°C. The overwintering insect period is usually the mature larvae or pre-pupa stage. ⑶ Relationship between occurrence and environment and temperature: The occurrence of Greater Wax Moth has a lot to do with the external temperature. The development of eggs and larvae requires a higher temperature (30-35°C). Too low or too high temperatures will slow the growth of Greater Wax Moth or even cause death. Relationship with food: Pure wax and new combs are not suitable for the development of Greater Wax Moth larvae, which will cause the larval development to be interrupted, the adult individuals to become smaller, and the egg-laying amount to decrease. The Chinese bee colony often replaces old combs, which plays an important role in inhibiting the occurrence of Greater Wax Moth. Relationship with colony strength: Due to hunger, disease, aging of queen bees, lack of queens, and pesticide poisoning, the number of worker bees has dropped sharply, resulting in a decline in colony strength, making the colony unable to protect exposed honeycombs and expel the invading wax moth larvae. Different bee species have different reproduction rates, and their colony strength varies greatly, and their resistance to wax moths also varies. For example, the colony strength of Chinese bees is small and unable to protect the honeycombs from harm. They often resist the harm of wax moths by constantly biting the honeycombs and removing wax moth larvae. Natural enemies include Bacillus thuringiensis, nuclear polyhedrosis virus, nematodes, wax moth wasps, wheat moth wasps, wax moth thigh wasps, red fire ants and big-headed ants. ⑷ Prevention and control methods ① Prevention methods In the bee colony, since it is difficult to use drugs to control wax moths and it will contaminate bee products, the principle of "prevention first, prevention and control combined" should be adopted, and the living habits of wax moths should be used to prevent their occurrence in feeding and management. By maintaining a strong colony, constantly cleaning the nest box and using new combs, the occurrence of wax moth can be effectively prevented. In addition, timely beating the adult moths and removing the pupae, egg masses and larvae in the box are also important measures to prevent and control wax moth. ② Treatment methods Physical control To prevent the contamination of bee products by chemical control, bee tools or bee products (such as honeycomb) can be frozen at -6.7℃ for 4.5h, -12.2℃ for 3h and -15℃ for 2h to kill wax moths of all stages. In addition, the use of water bubble combs, water immersion combs, water immersion beehives, frame ear barriers and other methods can also reduce the harm of nest insects. Chemical control agents are mainly used for stored combs, and chemical control within the bee colony is quite difficult. Fumigating combs with 36mg/L ethylene oxide for 1.5h can kill wax moths of all stages. Fumigating combs with 0.02mg/L dibromoethylene for 24h can also kill wax moths of all stages. In addition, the drugs commonly used to fumigate wax moths include carbon disulfide, glacial acetic acid, sulfur (sulfur dioxide), and methyl bromide. Biological control The most promising natural enemy of the greater wax moth may be the use of Bacillus thuringiensis. According to research, this bacillus and its toxins have no adverse effects on the treated bee colonies. Spraying bee colonies with Bacillus thuringiensis or impregnating nest foundations can prevent and control the greater wax moth. In addition, treating honeycombs with nuclear polyhedrosis virus can effectively prevent and control the greater wax moth. It is reported that radioactive mutagenesis of moths to suppress the greater wax moth population may be an important means of preventing and controlling the greater wax moth in the future. ⒉ Prevention and control of small wax moth ⑴ Morphological characteristics The eggs are watery white, oval, 0.39mm long and 0.28mm wide. There is no protection outside the eggs. The egg mass is single-layered, often with dozens to hundreds of eggs. The length of the larvae varies with the age. The first-instar larvae are water white, 1-1.3mm long; the old larvae are waxy yellow, 13-18mm long. The pronotum is brown, except for the pronotum spiracles and the 8th abdominal thorax, which are larger and oval, the edges of the other abdominal spiracles are dark brown. The pupa is spindle-shaped, with brown ventral surface and dark brown dorsal surface. The dorsal midline is ridge-shaped, and both sides are covered with keratinous protrusions. There are 8-12 large keratinized protrusions at the end of the abdomen. The female pupa is 8-12mm long and 2.3-3.1mm wide; the male pupa is 7-10mm long and 2.2-2.8mm wide. The cocoon is 11-20mm long, 3.2-4.8mm wide, and oblong. The silk cocoon is white, and it is common to see fecal particles on its surface. The moth adult, the female moth body is silver-gray, except for the head, the body has dark gray scales. The body length is 10-13mm, the antennae are brown, filamentous, and nearly half the length of the moth body. The head is covered with long light brown scales. The compound eyes are nearly spherical and are light blue to dark blue. The labial whiskers are short and thick and extend forward. The male moth is 8 to 11 mm long. The body color is slightly lighter than that of the female moth, and the antennae are also 1/2 longer than the moth body. The labial whiskers are small and curved upward. ⑵ Life history and habits The wax moth can produce 4 to 5 generations in Fujian in one year, and each generation lasts 2 to 2.5 months. The overwintering generation larvae begin to emerge in early March every year, and enter the overwintering dormancy stage from the end of November to the beginning of December. Generally, the pupal period of female moths is 7 to 9 days, and the pupal period of male moths is slightly shorter by about 1 day. After the emergence of female moths, they can mate after 2 to 3 hours. Female moths that successfully mate often start laying eggs that night. Female moths can lay eggs 3 to 5 times in their lifetime, with the first egg laying being the largest, usually 200 to 400 eggs, and the female moth lays 278 to 819 eggs in its lifetime. The life span of female moths is 4 to 11 days, with an average of 6 days; the life span of male moths is 6 to 31 days, with an average of 14.8 days, which is about twice that of female moths. The life span of unmated female moths is extended. Compared with the greater wax moth, the lesser wax moth is small and light, with a body weight of only 1/6 to 1/10 of that of the greater wax moth. The lesser wax moth raised on black honeycombs with fresh pollen has only 11.3 mg for adult male moths and 20.3 mg for female moths. The sex ratio of the lesser wax moths in the bee colony is close to 1:1, and sometimes there are slightly more males than females. The first eggs are water white; they turn light yellow after 2 to 3 days. The egg period of the lesser wax moth is 4 days. After hatching, the larvae live in the wax scraps on the bottom of the beehive, and later climb onto the honeycombs to damage the pollen and brood combs. The development period of larvae is affected by the external temperature and the quality of food. High temperature can shorten the larval period; dark combs have a short larval period, new combs and beeswax have delayed development and reduced generations. The wax moth hibernates as mature larvae hiding between the insulation and the bottom of the box or between the partitions and in various corners of the box. It rarely hibernates in the pupae or other insect stages. ⑶ Prevention and control methods The prevention and control of the wax moth is mainly through cleaning the nest box, using new combs, and timely beating the adults, removing the overwintering larvae, pupae and eggs. Its prevention and control methods are the same as those of the greater wax moth.