How to raise large silkworms well? Master these key techniques
Sericulture has a history of several hundred years in our country. In ancient times, people began to plant mulberry and raise silkworms, and since ancient times our country's silk industry has been developing quite well; therefore, our country's experience and techniques in sericulture are very rich. Now let's learn together with the editor about the relevant experience and techniques of sericulture.
The key to raising large silkworms well
When spring silkworms enter the fifth instar, silkworm farmers should, based on the weather forecast, note that the second half of May is mainly cloudy and rainy with lower temperatures, grasp the following seven key techniques, and take effective measures to raise large silkworms well.
1. Do a good job of disinfection and disease prevention in the silkworm room, mulberry storage room, silkworm body, and silkworm bed during the large silkworm stage
1. Use “Large Silkworm Disease Prevention No. 1” or “Silkworm Bed Clean” to disinfect the silkworm body once for newly molted silkworms; for silkworms raised in silkworm trays, remove excrement once a day and sprinkle fresh lime powder once; for silkworms raised on silkworm racks or on the ground, sprinkle fresh lime powder once a day, and in the middle of the fifth instar, remove the lower-layer twigs and remove silkworm droppings; silkworm droppings inside and outside the silkworm room should be promptly removed and cleaned, and after fermentation returned to the mulberry leaf field; starting from the 2nd day of the fifth instar, on sunny days every other day, especially the day before the silkworms are mounted on the cocooning frames, spray the body once with “Miecanying”. Generally, 1 tube of Miecanying is mixed with 1 jin of water.
2. For farmers whose silkworms have already developed muscardine, every other day, in the morning or evening before feeding mulberry leaves, use “Xunxiaojing” to fumigate and disinfect the space of the silkworm room and mulberry storage room once; generally, for a 9 m long silkworm room, use 1 packet of “Xunxiaojing” when no diseased silkworms are found, and use 2 packets when diseased silkworms are found; during fumigation and disinfection, close doors and windows for half an hour, then open doors and windows, ventilate and exchange air before feeding mulberry leaves.
3. Before each feeding of mulberry leaves, first pick out dead and diseased silkworms and put them into a vat of lime or bleaching powder, wash both hands clean, disinfect them, and then feed mulberry leaves.
2. Master the temperature during the large silkworm stage well and do a good job of ventilation and air exchange in the silkworm room
The temperature during the fifth instar must not be lower than 20°C. If the temperature is too low, it is easy to make the silkworms weak and cause disease in the late fifth instar. Therefore, when the temperature is low from night to morning, doors and windows can be appropriately closed for heating work; during the day, even if the temperature is low, when heating, doors and windows should still be opened to ventilate and raise silkworms, ensuring fresh air in the silkworm room. If ventilation in the silkworm room is poor, an electric fan or exhaust fan can be used, which is beneficial to the health of the silkworms.
3. Raise large silkworms sparsely so they eat well and eat their fill
From the 3rd to the 4th day of the fifth instar, the silkworm bed should be expanded to the largest area. Generally, 1 batch of silkworm eggs should reach 40-45 silkworm trays, and ground rearing and rack rearing should reach an area of about 40 sq m; the amount of mulberry fed should preferably be controlled so that the leaves are eaten up or only a little residue remains.
4. Prevent silkworm poisoning caused by the use of rice straw in sericulture, and use rapeseed stalks as little as possible to prevent the occurrence of acariasis.
Because rice pests and diseases occurred severely last autumn, many types of pesticides were used in rice fields and the frequency of use was high, so the residues of pesticides in rice straw are large. According to tests by the Economic Crops Bureau of the Provincial Department of Agriculture, when rice straw was used as bedding straw and cocooning material, multiple samples showed poisoning symptoms. Therefore, it is hoped that the vast number of silkworm farmers will not use rice straw as bedding straw for raising large silkworms, nor use rice straw as cocooning material, to prevent silkworm poisoning. For many farmers who raise silkworms on the ground, if rapeseed stalks are used as bedding straw, the silkworms are prone to acariasis, so rapeseed stalks should be used as little as possible to prevent the occurrence of silkworm diseases.
5. Maintain good relations with neighboring fields and prevent pesticide poisoning of silkworms
Mulberry fields are not contiguous, and there are many situations where they are interplanted with tea or vegetables, etc. To prevent pesticide poisoning of silkworms, farmers should maintain good relations with neighboring fields, and before each feeding of mulberry leaves, first test with a small amount of silkworms to ensure there is no toxicity before feeding mulberry leaves in large quantities; when silkworms are poisoned, timely symptomatic rescue must be carried out.
6. Do a good job of management during cocooning to improve cocoon quality
The cocooning room should be chosen upstairs where it is dry. The technique of pre-mounting on square cocooning frames outdoors should be actively promoted and applied. Ventilation in the cocooning room should be strengthened. If the temperature is low, appropriate heating should be used, but doors and windows must not all be closed; an exhaust fan or electric fan can be used to prevent the cocoons from turning yellow.
7. Do a good job of summer pruning in a timely manner
In recent years, many varieties of the Nongsang series have been developed. In accordance with the situation in recent years after summer pruning that the Nongsang series have much sap flow and poor sprouting. When pruning branches, choose a sunny day, leave 1-2 small thin branches per mulberry tree or leave 2-3 leaves at the three-eye stage at the base, and prune after 3 days to increase the sprouting rate.
Is sericulture profitable
Mulberry silkworm cocoon breeding is divided into spring silkworms, summer silkworms, and autumn silkworms; autumn silkworms are further divided into mid-autumn silkworms and late-autumn silkworms. Spring silkworms have the best quality, followed by autumn silkworms. Breeds raised include Nongsang, Dazhonghua, etc. The growth cycle of mulberry silkworm cocoons is limited by temperature. Each spring, spring silkworms begin to be raised around April 20, with 26-27 days as one growth cycle. Summer pruning begins around May 20. After the mulberry trees grow new leaves again, summer silkworms begin to be raised around June 25, with 24-25 days as one growth cycle. Because the interval between mid-autumn silkworms and summer silkworms is short, and poor disinfection may affect growth and quality, mid-autumn silkworms are generally not raised. Late-autumn silkworms generally begin to be raised around September 5 and end in early October. For the summer silkworm season, due to the influence of temperature, environment, purchase prices, and other factors, some farmers choose to raise two seasons, spring silkworms and autumn silkworms, while others choose to raise three seasons of silkworms. From the survey, it was learned that: one mulberry sapling costs 0.4 yuan, 1440 are planted per mu, 7-8 years is one cycle, and the average annual investment in mulberry trees is 87.27 yuan/mu.
The net profit per mu for mulberry silkworms is 7542.49 yuan, and the price per 50 kg of mulberry silkworms is 2817 yuan. Due to rising purchase prices, cocoon income has increased. In recent years, cocoon silk processing enterprises have grown rapidly, and the total output of cocoon silk processing and the total demand for raw material cocoons have risen substantially; in order to maintain normal production, cocoon silk processing enterprises have no choice but to jointly purchase raw materials even when raw material cocoon prices are high and profit margins are not large.
Analysis of the market prospects of sericulture
From the perspective of the international market, as the traditional capital of mulberry planting and silkworm raising, our country's silk and silk-processed products are deeply favored by countries around the world, and consumption of silk is growing. According to incomplete statistics, our country's silk products are sold to 140 countries, and among these countries and regions, the United States, Japan, and Southeast Asia are the main trading partners. After the 2008 financial crisis, with economic recovery, our country's silk exports have risen steadily in recent years, and the huge demand in the international market and the favor for our country's silk have brought greater development space to our country's mulberry silkworm industry.
From the perspective of the domestic market, in earlier years silk, as a high-end consumer product, had a very small share of consumption in our country's market, and per capita silk consumption was far below the world average. As people's material living standards improve, the quality requirements for home textile products are also increasing. Silk, as a high-end home textile consumer product, is also entering ordinary households. When our country's huge potential market is tapped, it will bring huge business opportunities to the entire silk industry and push the entire industry into a fast track of development.
How to raise summer and autumn silkworms
The key factors determining the success or failure of raising summer and autumn silkworms are first leaf quality, climate, and pests and diseases, followed by silkworm breeds, sericulture techniques, and equipment conditions, etc. Therefore, to raise autumn silkworms well, it is necessary to carefully analyze the factors affecting summer and autumn silkworm production, grasp the key points, seize the timing, create conditions, and ensure stable and high yields of summer and autumn silkworms.
1. Strict disinfection and disease prevention. The interval between silkworm seasons is short, pathogens are fresh, and the amount is large, making infection easy, so thorough disinfection should be carried out for the environmental hygiene of the silkworm room and silkworm tools. Adopt the method of first spraying disinfectant, then cleaning, dismantling, and washing. The spraying dosage should be sufficient and every surface should be sprayed. Strictly implement the “three disinfection guidelines” of “thorough disinfection before silkworms, continued disinfection during silkworms, and immediate disinfection after silkworms”, and carry disinfection and disease prevention through the entire sericulture process.
2. Adjust the silkworm room temperature. According to the different climate characteristics of summer and autumn, take corresponding measures to adjust and improve the sericulture environment. During the young silkworm stage, use plastic film covering for rearing, which can preserve warmth and moisture and is beneficial to the healthy development of silkworms. During the large silkworm stage, choose tall, spacious, and well-ventilated houses for rearing to prevent stuffiness. Trees should be planted around the silkworm room and a shade shed built to reduce radiation. In high temperature and stuffy conditions, strengthen ventilation and air exchange; in high temperature and dryness, lower the temperature and supplement moisture.
3. Strengthen mulberry leaf management. Strengthening fertilization and pest control for mulberry trees and promoting mulberry tree growth is the guarantee for a bumper harvest of summer and autumn silkworms. During the young silkworm stage (1st-3rd instar), pick appropriately mature leaves, with the standard being proper green color and soft feel. In particular, the mulberry leaves used for receiving newly hatched silkworms should be appropriately mature and slightly tender.
From the above analysis, we can easily see that sericulture has very good market prospects. Our country's silk is not only very popular domestically, but is also greatly favored abroad. Therefore, on the road of sericulture, as long as you dare to think and dare to act, you can certainly obtain the wealth you want.