Why did the Chinese treasure the silkworm butterfly? Silkworm: interesting facts and photos
I recently bought silk scarves for my collection, made by Uzbek craftsmen using the ancient ICAT technique. The technique is incredibly labor-intensive, because it is manual... everything is done by hand, starting from cutting mulberry branches to feed the silkworm caterpillars...
The photo of watermelons is not related to silkworms, but it is relevant to the further discussion. All photos have captions if something is not clear.
Woman selling watermelons at the bazaar in Andijan, Uzbekistan
But at the beginning of the conversation I will show you my purchases. It’s not that I’m bragging... now such things are available for purchase via the Internet and cost quite reasonable money, considering the labor-intensive processes - so almost for nothing, I think. Rather, I admire these products and it’s a pleasure to simply own them. I am glad that I have them, like small grains of the world of my childhood, particles of my Motherland... I wrote earlier that I was born in Central Asia and from birth I saw this colorful world. We went to the market, and there they sold fabrics, and there were mountains of watermelons and melons, spices, ripe tomatoes, and apples and cherries grew on the trees just like that... A strange world...
This is how they sell onions at the bazaar in Fergana, and throughout Central Asia So, shopping. Two scarves, blue-yellow and red-green. , length about 170 cm, width 49 cm. Scarves are so narrow because they are woven by hand on narrow looms. In Uzbekistan, it is customary that all ikat (fabric made using the ICAT technique, also called “Uzbek pattern”, pictured below) are woven narrow, because this width is convenient for handwork.
Silk scarf ikat shoyi, Uzbekistan 
Second 
My silk scarf ikat shoyi, Uzbekistan 
My silk scarf ikat shoyi, Uzbekistan These scarves are made from 100% natural silk. This can be checked in this way: set fire to a small piece of material, it is enough to set fire to even 1 thread, which is what I did.
Natural silk, when burned, quickly forms a black lump, and this lump smells like burnt horn or feather (which is chemically the same thing, keratin), which easily rubs in your hands (see photo) into dust.
The unnatural material will melt and there will be a lump at the end of the burnt thread…. how to put it more precisely... like lava, such a clot... and it does not rub into dust with your fingers. Viscose, when burned, smells like burnt paper (paper, in fact, it is, since it is made from cellulose), and polyester, which is generally synthetic, will melt and burn without a residue.
Two scarves, blue-yellow and red-green... the threads are dyed with natural dyes, but I will talk about the ikat production technology in the next article, and now a little about silk production in general.
Silk is chemically a protein (protein), so they are called: “silk proteins” and are a long-long chain polymer, more precisely, a “bundle” of these polymers. This polymer (which is silk) is produced internally (like a microfactory!) and released from itself by the silkworm caterpillar at a certain age. These silkworms were domesticated in China 5,000 years ago, but what does "domesticated" mean? In this case, this means that they are selected to obtain a better product, mated with the right person (although females can lay eggs without mating) to increase the size of the cocoon and the thickness and length of the thread in it, its growth rate and efficiency ( cocoon) digestion, their (caterpillars) resistance to disease. In the same way, tolerance for human presence and living “on top of each other” was changed (see photo below, this does not happen in nature). All these modifications have made the domestic silkworm completely dependent on humans... for its survival
Silkworm breeding in Thailand, final stage, cocoons before boiling The silkworm, like the Drosophila fly, reproduces and grows quickly, so it is easy to track various gene modifications on it. I read the following phrase: “The silkworm is one of the most genetically exploited animals.” Over the 5000 years of domesticated existence, the silk productivity of silkworm varieties has increased almost tenfold relative to its wild ancestors (only corn is ahead of the silkworm in this parameter...). Scientists are also trying to genetically influence the duration of various stages of life of silkworm larvae and caterpillars, and health, productivity, quality of silk, resistance to various pathogens... a lot of different things depend on them, in turn.
Silkworm cocoons at a silk factory. Looks like it's China. I will briefly describe the process of obtaining silk.
In the summer, silkworm butterflies (after mating with a male silkworm) lay eggs: these eggs are called "grena". This grain is placed in the refrigerator until spring, that is, until the new season. The next spring, with a gradual artificial increase in temperature from 18 to 25 degrees and a certain humidity, the grena awakens, it is checked for the presence of diseased and defective (I don’t know how they do this, apparently from the color of the masonry... something came to mind), then from grenas hatch into 2 mm worms (silkworm larvae). These worms eat crushed mulberry leaves day and night, devour them and grow, devour and grow (and within a month increase in size up to 3-4 cm)... This time of growth and weight gain is quite difficult for the maintenance staff of the greenage factory (so are called factories where silkworm caterpillars are raised from their eggs. Such a factory was in the city of Osh, where I was born): the caterpillars are in large trays with mulberry leaves and are very sensitive to sounds, smells, changes in temperature, humidity, pressure (these caterpillars are not simple, but domesticated already in ancient times and varietal, highly productive, not the same as in simple nature. Well, like a wild orange and a cultivated one... I wrote about this above).
pallets with silkworm caterpillars and crushed mulberry leaves If you don’t follow the rules, the caterpillar will simply die and all your work will be in vain...
Silkworm caterpillars molt 4 times during growth (they also grow and their skin becomes small for them), while their appetite grows almost exponentially.. The color and appearance of the caterpillars changes greatly from molt to molt, in the bottom photo these are white caterpillars with a horn, judging by the description, are in the 5th instar stage (shortly before pupation).
There are so many caterpillars and they eat the leaves so loudly that you can hear it... And then the time comes for metamorphosis into a pupa... the skin of the caterpillars becomes stronger and yellower and silkworm breeders transfer these caterpillars to special branches or nets (like the one in the photo), to which the caterpillars attach and begin to form a silk cocoon.
Formed silkworm cocoons To form a cocoon, the caterpillars begin to secrete a certain substance from special glands that hardens in air. This substance is a mixture of the protein fibroin and sericin (and some other little things), it’s called “raw silk”, it is thread-like and the caterpillar wraps it around itself, forming a cocoon around itself. First, the caterpillar forms an outer fluff (see in the photo, it’s shaggy), and then inside this fluff wraps the main mass of silk thread around itself.
Traditional Thai mulberry silk - from these yellow cocoons that are produced by the silkworm Bombix Mori These cocoons are urgently collected and transported to silk-spinning factories in order to catch the moment of metamorphosis of the pupa into a butterfly... the fact is that when the pupa in the cocoon turns into a butterfly (the butterfly does not have a mouthpart), it secretes a proteolytic enzyme (an enzyme that destroys the silk shell of the cocoon , called protease) to get out and fly away to mate. But the cocoon is a CONTINUOUS long thread of silk (from 300 to 900 meters), which the butterfly has wound around itself, and if you pierce the cocoon, you will not get a continuous thread, but short stubs... These stubs are also used, but it will not be high-quality silk thread, it will be a completely different product...
So, the cocoons are taken to a silk spinning factory to extract silk from them. Now, instead of a large factory, there are small handicraft workshops, but this has not changed the essence of the process, and the quality of the products remains excellent.
This is how silk cocoons are steamed and unwoven into threads, Margilan, Uzbekistan First, the cocoons are sorted by size and color. Then, in order to kill the under-butterfly inside the cocoon, these cocoons are steamed in hot water (boiled, in short). The cocoons swell, part of the silk protein mixture from which the caterpillar made the cocoon dissolves in water (this is the substance I wrote about it above; the caterpillar does not secrete pure silk proteins, but a mixture of different proteins; some of them are actually silk proteins (fibroin) , and others are like glue for gluing silk threads together to form a cocoon (sericin + resins and something else), the cocoon itself feels dense to the touch, like thin felt...). So this kind of glue dissolves in water, releasing the silk threads. Now we need to unwind the cocoons, but it’s not easy.
Silkworm cocoons in hand, Margilan, Uzbekistan. They begin to unwind the cocoons on threads In large silk-spinning factories, the process of unwinding cocoons is mechanized, but in small farms it is done manually... I won’t say exactly how, but they grab the threads (look at the photo) and begin to pull them, essentially unwinding the cocoons... What follows is the subtleties of the process: a thread of raw silk is formed from 3-10 threads from cocoons, if one of the threads breaks or ends, then a new thread is attached, simply glued: the remains of adhesive sericin are what connect all the tiny threads together. But I’d better say that boiled silkworm pupae (from cocoons) are often used for food. The photo shows cocoons and their contents, that is, silkworm pupae
White cocoons and silkworm pupae. Boiled dolls are eaten in Korea In South Korea, for example, they are a delicacy (I myself saw how they are sold on the streets and eaten, brrrrr.. this popular snack is called 번데기 or Beondegi, in my opinion they have such a characteristic and disgusting smell...)
Silkworm snack boiled silkworm pupae Raw silk (which is pulled from the cocoons) is wound into skeins. In the left corner of the photo you can see a skein (a bunch hanging on a stick) of silk, and the thread is wound on a “drum”.
Reeling and spinning silk, Margilan, Uzbekistan And below in the photo a woman is spinning a silk thread (that is, twisting it)
Just curious: the life cycle of the silkworm 
In writing the article, I used information from my memory, and took some things from the articles of the master Ksenia Semencha and here http://www.suekayton.com/silk.htm, and bought scarves from Anastasia Bulavka. Part of the photo from the site http://www.projectbly.com/, part of https://www.flickr.com/photos/adam_jones/
Niramin - Feb 23rd, 2017
The silkworm lives almost nowhere in the wild. The ancient Chinese domesticated this beneficial insect 4.5 thousand years ago. Despite the fact that the Chinese kept the process of producing natural silk a closely guarded secret for a long time, it became known in other countries where there are optimal conditions for growing silkworm larvae.
An ancient legend says that a Chinese princess, having married an Indian rajah, secretly took with her a clutch of silkworm eggs when she left China. It is worth noting that such an act was considered a state crime, and the princess faced the death penalty in her homeland. Nowadays, silkworm breeding is carried out on special farms in Asian countries: China, Japan, India, Pakistan, North and South Korea, Uzbekistan and Turkey. In addition, similar farms exist in Italy and France.
Like most insects, the silkworm looks different during its life, as it goes through several stages of development:
Grena stage - laying eggs.
Photo: Silkworm laying eggs. 
Caterpillar (larval) stage.
Photo: Silkworm caterpillars. 
Pupation (cocoon formation).
Photo: Silkworm cocoons. 
The adult stage is a butterfly.
Photo: Silkworm - butterfly. 
The white butterfly is quite large in size with a wingspan of about 6 cm. During the process of natural selection, the silkworm butterfly lost the ability to fly. During its short existence of about 20 days, the butterfly does not feed. Its main function is to mate and lay up to 1000 eggs in one clutch, after which the butterfly dies.
Depending on a certain temperature, black, hairy larvae emerge from the eggs. During its development, the larva molts several times and becomes a smooth white caterpillar.
It is the caterpillar that feeds exclusively on mulberry leaves.
Photo: Mulberry tree with fruits.
Any other plant food is not suitable for her. Hence the name of the insect. After 5 weeks of intensive calorie consumption, the caterpillar attaches itself to a suitable branch and forms a cocoon of silk thread, which it produces thanks to the presence of a special gland. The transformation of a caterpillar into a butterfly occurs in the cocoon. To obtain silk thread, farmers do not allow the butterfly to emerge from the cocoon. But a certain number of cocoons are still left for butterflies as successors to the next generation of silkworms.
Video: MULIWORM 6th grade
Video: What is it made of? (S7). Silk.
Video: Animals in history. Silkworm
Video: Silkworm cocoon Uzbekistan
The silkworm is a very interesting insect, which has been known to man since ancient times as silk source. According to some data mentioned in Chinese chronicles, the insect became known as early as 2600 BC. The process of obtaining silk was a state secret for centuries in China, and silk became one of the clear trade advantages.
Starting from the 13th century, other countries, including Spain, Italy, and North African countries, mastered the technology of silk production. In the 16th century, technology reached Russia.
Nowadays, the silkworm is actively bred in many countries, and in Korea and China it is used not only to produce silk, but also for food. The exotic dishes that are prepared from it are distinguished by their originality, and silkworm larvae are used for the needs of traditional medicine.
India and China are leaders in silk production and it is in these countries that the number of silkworms is greatest.
What does a silkworm look like?
This insect earned its unusual name thanks to the tree it feeds on. Mulberry, a tree also called mulberry, is the only source of food for the silkworm.
Silkworm caterpillar eats a tree day and night, which can even lead to its death if the caterpillars occupy such trees on the farm. To produce silk on an industrial scale, these trees are grown specifically to feed insects.
The silkworm goes through the following life cycles:
The silkworm butterfly is a large insect, and its wingspan reaches 6 centimeters. It has a white color with black spots; there are notches on the wings, in the front part of them. Pronounced comb mustache distinguish males from females, in whom this effect is almost invisible.
The butterfly has practically lost the ability to fly and modern individuals spend their entire lives without rising into the sky. This was caused by their very long detention in unnatural living conditions. Moreover, according to available facts, insects stop eating food after turning into butterflies.
The silkworm acquired such strange features because it was kept at home for many centuries. This has now led to the insect cannot survive without human guardianship.
Over the years of its breeding, the silkworm has managed to degenerate into two main species: monovoltine and multivoltine. The first species lays larvae once a year, and the second - up to several times a year.
Hybrid silkworms can have many differences in characteristics such as:
- body shape;
- wing color;
- dimensions and general shape of the butterfly;
- dimensions of the pupa;
- color and shape of caterpillars.
The larvae or eggs of this butterfly are scientifically called grena. They have a laterally flattened oval shape, with elastic transparent film. The dimensions of one egg are so small that per gram of weight their number can reach two thousand.
Immediately after the butterfly lays its eggs, they have a light milky or yellowish color. As time passes, changes occur, leading to the appearance of a pink tint in the larvae, and then to a complete change in color to purple. If the color of the eggs does not change over time, it means the larvae have died.
Silkworm eggs have a fairly long maturation period. He lays them in the summer months: July and August, and then they hibernate until spring. The processes occurring in them at this time slow down significantly in order to survive the effects of low winter temperatures.
If the grena overwinters at temperatures not lower than +15 degrees, then there is a risk of poor development in future caterpillars, so in winter it is necessary provide for grains optimal temperature conditions. Caterpillars appear before leaves have time to grow on the trees, so grena is stored in refrigeration units at temperatures from 0 to -2 degrees throughout this period.
The caterpillars of this butterfly are also called silkworms, which cannot be considered a scientific name. Externally, silkworm caterpillars look like this:
Immediately after birth, the caterpillar has a very small size and weight, not exceeding half of one milligram. Despite this size, all biological processes in the caterpillar proceed normally, and it begins to actively develop and grow.
The caterpillar has very developed jaws, pharynx and esophagus, due to which all consumed food is absorbed very quickly and well. Each of these little caterpillars has more than 8,000 muscles, allowing them to bend into intricate poses.
In forty days, the caterpillar grows to more than thirty times its original size. During the period of growth, she sheds her skin, which for natural reasons becomes small for her. This is called molting.
During molting, the silkworm caterpillar stops eating tree leaves and finds a separate place for itself, usually under the leaves, where it tightly attaches itself to them with its legs and freezes for some period. I also call this period the caterpillar's sleep.
As time passes, the head of a renewed caterpillar begins to emerge from the old skin, and then it comes out entirely. At this time you cannot touch them. This can lead to the fact that the caterpillar simply does not have time to shed its old skin and dies. During its life, the caterpillar molts four times.
The intermediate stage in the transformation of a caterpillar into a butterfly is the cocoon. Caterpillar creates a cocoon around itself and inside it turns into a butterfly. These cocoons are of greatest interest to humans.
The moment when a butterfly should be born and leave its cocoon is very easy to determine - it begins to move literally a day before, and you can hear light tapping sounds inside. This knocking appears because at this time the already mature butterfly is trying to free itself from the skin of the caterpillar. A curious fact is that the time of birth of the silkworm butterfly is always the same - from five to six in the morning.
A special liquid, similar in consistency to glue, which is secreted by butterflies, helps them free themselves from the cocoon by splitting it.
The lifespan of a moth is limited to only twenty days, and sometimes they do not even live up to 18 days. In this case it is possible meet long-livers among them who live for 25 and even 30 days.
Due to the fact that the jaws and mouth of butterflies are not sufficiently developed, they cannot feed. The main task of the butterfly is procreation, and during their short life they manage to lay many eggs. In one clutch, a female silkworm can lay up to a thousand of them.
It is noteworthy that even if an insect loses its head, egg laying process will not be interrupted. The butterfly's body has several nervous systems, which allows it to continue laying eggs and live for a long time, even in the absence of such a significant part of the body as the head.
Natural silk is a wonderful fabric that has no analogues; its history is steeped in ancient legends, and the production process has changed little over several millennia.
The publication will also be of interest to fans of felting, because Tussa and Mulberry silk, as well as silk scarves, tows, cocoons and other materials are widely used in wet felting.
So where does silk come from?
Natural mulberry silk (
Probably, almost everyone knows that we are provided with natural silk by amazing worms - unsightly-looking caterpillars (larvae) of the silkworm. High quality silk is produced by these worms, and is often called "mulberry silk" or Mulberry silk(Mulberry is a mulberry tree translated from English), we call the mulberry tree mulberry and many people love its fruits. And the larvae love leaves and turn them into silk thread.
Silkworm (scientific name Bombyx mori- lat. ) - a butterfly from the family True silkworms, translated from Latin Bombyx mori means "death of the silkworm" or "dead silk". The name comes from the fact that the butterfly is not allowed to fly out of the cocoon, it dies inside.
The butterfly is very impressive, it has also been called “silk moth”: The wingspan is 4-6 cm, the caterpillar can grow up to 9 cm before pupation.
It is believed that the Bombyx mori butterfly originated from a wild silk butterfly that lives on the mulberry trees of China. This was a very long time ago, it is believed that the history of silk production goes back at least 5,000 years, and over a long period of breeding butterflies in captivity, they lost the ability to fly well. Females practically do not fly, males fly a little during the mating period, so to speak, in moments of elation.
Process of obtaining raw mulberry silk
The butterfly, having hatched from the cocoon, mates with the male, and then begins to lay eggs. In 4-6 days she lays up to 800 eggs, does not eat anything, because... its oral apparatus is underdeveloped, and after finishing its work, it dies. Eggs are checked, selecting healthy ones that are not affected by infection. In this way, the quality of future silk and the reproduction of healthy butterflies are controlled.
Each egg after a week gives rise to a larva of about 2-3mm with an unimaginable appetite. The larva must be fed regularly day and night for a month with mulberry (mulberry) leaves. The leaves are collected, sorted by hand and crushed. All this time, the larvae are kept in large trays with leaves, placed one on top of the other in a special room with constant temperature and humidity. The larvae are surprisingly sensitive - there should be no drafts, foreign odors or loud sounds in the room. What can happen if the conditions are not met? it’s just that the caterpillar will not spin a cocoon, it will die, and all the efforts of the silkworm breeders will be in vain.
The caterpillars' appetite is constantly growing, and within a day they eat twice as much as the previous day.
The constant work of the huge number of silkworms' jaws in the room produces a roar similar to the drumming of heavy rain on the roof.
On the fifth day of life, the larva freezes and sleeps for a day, tightly grasping the leaf. Then it straightens up sharply, and the old tight skin bursts, releasing the grown caterpillar. During the feeding period, the larvae change their skin 4 times and return to eating.
Before pupation, the caterpillars lose interest in food and begin to behave restlessly, constantly shaking their heads back and forth. Under the lower lip there are glands that produce silk substance. At this point, they represent 2/5 of the body weight, and are so full that a silk thread trails behind the caterpillar.
Sericulture breeders move the caterpillars onto floorings of leaves and branches, onto wooden grates or special bundles of rods for spinning a cocoon.
First, the caterpillar is attached to a twig or other base, creating a fluffy mesh frame, and only then it spins a cocoon inside it. It begins to secrete a gelatinous substance, which hardens in the air, forming a silk thread, and with rotational movements it wraps itself around this thread in the shape of a figure eight.
The thread consists of 75-90% protein - fibroin and the adhesive substance sericin, which holds the threads together and prevents them from falling apart; the thread also contains salts, fats and wax. The caterpillar completes the cocoon in 3-4 days.
An interesting fact: the cocoons of males are made more carefully - they are denser and the length of the thread is longer than those of females. Those who have ever held cocoons in their hands know how pleasant and silky they are to the touch.
After 8-9 days, the cocoon is ready to unwind. If you miss the time, after 2 weeks the butterfly will emerge from the cocoon, damaging the silk shell. Because The butterfly's mouthparts are undeveloped; it does not gnaw through the cocoon, but secretes a special caustic substance that dissolves the upper part of the cocoon. Such a cocoon can no longer be unwound; the thread will be torn.
Therefore, the pupa is killed by heating the cocoons with hot air, and it suffocates in the cocoon, which is where the name “death of the silkworm” or “dead silk” comes from.
Here it is, a wonderful raw material for silk!
The cocoons are sorted by size and color and prepared for unwinding.
Wash alternately in hot and cold water. The adhesive substance sericin, which holds the threads together, dissolves enough to allow the thread to be unwound.
According to all sources studied, only the unwinding of thread is mechanized at present; all previous stages of production remain completely manual labor, as in ancient times.
The thread of one cocoon is very thin, so when unwinding, from 3 to 10 threads are connected, thus obtaining raw silk. When one of the threads ends during the winding process, a new one is screwed onto it, ensuring continuity. The sericin (sticky substance) remaining in the thread helps to easily hold the ends of the thread together.
Raw silk requires further processing; it is wound into yarn and sent to a weaving factory. Factories buy silk by weight, but during further processing such raw silk loses 25% of its weight - it is soaked to remove residual sericin and bleached. To compensate for their losses, factories enrich silk with metal salts or water-soluble substances - starch, sugar, glue or gelatin. Such impregnations make it possible to weave threads more economically and compensate for weight loss during weaving.
The sources don’t say it directly, but I think that’s why natural silk shrinks quite a bit when washed. After all, if you wash salts or water-soluble impregnations from the fabric, the fabric will shrink the freed space.
After unwinding the cocoons, a dead pupa remains, which is rich in protein and can be eaten!
Nowadays, the silkworm culture is bred exclusively artificially. The cocoons that the silkworm caterpillar weaves can be of various shades from white to yellow and even grayish. The white variety of cocoons contains the highest percentage of silk protein and produces the best quality silk. Produced by silkworms in Japan, China and India. Japan was the first to apply a scientific approach to the selection and breeding of silkworms in special laboratories, and now surpasses other countries in the efficiency of silk production, but China is the leader in production volumes.
It is believed that France and Italy make silk fabric of higher quality than Asian countries. But the raw material, raw silk, is purchased by European manufacturers in China.
Fabric white Chinese silk:
I came across this example: a woman’s blouse requires a thread from 600 silkworm cocoons.
Traditional Thai mulberry silk obtained by processing yellow cocoons, which are produced by another variety of silkworm, Bombix Mori. The breeding process is similar.
Yellow cocoons contain less silk protein, and the thread is uneven - it has thickenings. When twisted, the thread turns out to be uneven, and on Thai-made silk we see such characteristic thread thickenings. Again, the entire production process is manual labor, often even unwinding is done by hand, so Thai silk is quite expensive and in Thailand is only available to wealthy Thais.
Thai silk fabric:
Natural "wild silk", "tussah silk (Tussah, tussar)"
What is it and how is it different from mulberry?
This silk is “wild” because the butterfly is grown in natural conditions, on bushes and trees, which are at most protected by canopies. Sericulture breeders only look after the caterpillars and protect them from birds. Silk cocoons are collected after the butterfly has left the cocoon, and the butterflies are completely different - Antheraea, a species of nocturnal peacock eye who are called oak silkworm. The butterflies are large, fly well, and the caterpillars grow up to 10cm before pupation.
Chinese oak silkworm (there are Japanese, Mongolian and other varieties). The wingspan of the butterfly is 10-15 cm.
They can feed on oak, apple, plum or chestnut leaves, and their cocoons are distinguished by a brownish color and a coarser and stronger thread. The cocoons are large, several times larger than mulberries, and can reach the size of a small chicken egg.
Some sources write that the thread is difficult to unwind, and the silk fiber is combed from the cocoon, while others say that the thread unwinds perfectly. I don't know where the truth is!
Also, wild silk has less shine; its thread does not shine evenly, but seems to sparkle.
Silk obtained in this way is not bleached to a pure white color. The fabric is durable and is often used for interior decoration and the production of very durable, dense silk suiting fabrics.
Personally, I’ve been itching to paint it for a long time, it will be a gorgeous skirt, but I still don’t have time.
Dyed wild silk fabric:
I hope, dear readers, that the article was interesting to you. Personally, in the process of writing, I learned a lot of new things for myself and understood, having appreciated the scale of manual labor, why real natural silk cannot be cheap :)
The photos in the publication are most likely small private farms in Asia. In China, it is very common for farmers to raise silkworms and then sell the cocoons by weight for further processing.
The article was written using materials from various Internet sites.
AuthorIt is interesting that the mentioned adhesive substance sericin is named after the ancient people of Sera, who, according to the records of historians that have reached us (Herodotus), have been engaged in the production of silk since ancient times.
As you can see, silk is produced by different silkworms, not just mulberries.
The Siberian silkworm, which is a pest, is widespread in Russia:
“Under favorable weather conditions for development, they are capable of significantly increasing their numbers in a short period of time. Thus, an outbreak of mass reproduction of harmful forest insects occurs. The total area of active foci of pests and diseases in 2001 amounted to more than 10 million hectares. Almost 70% This area accounted for the Siberian and gypsy moths.Focuses of the Siberian silkworm in Yakutia on an area of 6 million hectares became extinct after extermination measures and under the influence of natural causes.
The most dangerous pests in Siberia are the Siberian silkworm (the main range is the Irkutsk region, the Republic of Buryatia and the Krasnoyarsk Territory) and the black longhorned beetle (the main range is the Krasnoyarsk Territory). The Siberian silkworm has pronounced ecological variability, differing in different parts of its range in the set of preferred food species and features of population dynamics, which allowed A.S. Rozhkov (1963) identified several regions where it feeds on certain types of food plants and outbreaks of its mass reproduction occur with similar dynamics (Fig. 6). The area of forests damaged by this dendrophage in just 40 years of the 20th century (1930-1970) amounted to more than 8 million hectares for Central Siberia alone (Kondakov, 1974).
Of the forest diseases, fir canker is the most widespread (445 thousand hectares). The main area of this disease in Siberia is the Kemerovo region.
The general deterioration of the forest pathological situation in the forests of the Russian Federation, in addition to the biological characteristics of pests and diseases, is caused by a complex of factors unfavorable for forest ecosystems and a number of organizational shortcomings of the forest protection service, such as a limited number of specialists in the regions, insufficient funding for forest pathological expedition surveys, extermination measures, etc. "
Distribution area of the Siberian silkworm:
The harmfulness of the Siberian silkworm, according to A.S. Rozhkov (1963):
1 - the greatest harm; 2 - significant harm; 3 - minor harm; 4 - possible harm.
That is, even in the current harsh climate of Yakutia and the Krasnoyarsk Territory, Siberia, the silkworm actively reproduces, posing a threat to forests. In the past, Siberia was a much more suitable place, judging by the rich flora and fauna, the remains of which are found by scientists during excavations. And the preserved piece of the tropical jungle of Primorye clearly illustrates what the climate was like in the past. When the warm Pacific current worked to heat the Far East and Siberia.
In fact, the northern border of the silkworm’s range now lies in Primorye:
Sericulture is the breeding of silkworms to produce silk. According to Confucian texts, silk production using the silkworm began around the 27th century BC. e., although archaeological research suggests the breeding of silkworms as early as the Yangshao period (5000 BC). In the first half of the 1st century AD. e. sericulture came to ancient times Khotan,, and at the end of the 3rd century - to India. Later it was introduced in other Asian countries, in Europe, in the Mediterranean. Sericulture has become an important industry in the economies of several countries such as China, the Republic of Korea, Japan, India, Brazil, Russia, Italy and France. Today, China and India are the two main producers of silk, accounting for about 60% of the world's annual production.
Khotan, historical background:
The history of the city is inextricably linked with the functioning of the Great Silk Road, which from here went either to the south, to India, or to the west, through the gorges of the Pamirs. In ancient times, the oasis was inhabited by speakers of the Tocharian language, who early adopted Buddhism and whose mummies were discovered by European researchers at the beginning of the 20th century.
It is likely that the local monks were the first to introduce the Buddhist faith to the Chinese, who were attracted to Khotan by the reserves of jade, a highly valued ornamental stone at the emperor’s court.
From about the 2nd century BC. e. The oasis is inhabited by Saka Iranian-speaking tribes, who left quite numerous monuments of Buddhist literature in the Khotanosaki language of the 1st millennium BC. e. Their appearance is associated with the actual foundation of the city and the receipt of the name known to us (Iran. xvatan). Starting from the 9th-10th centuries, the Khotanosak language was gradually replaced by Turkic dialects.
The Khotan oasis (called 和阗 in old Chinese texts) marked the limit of the spread of Chinese borders during the Han (Ban Chao's troops visited here in 73) and Tang (there was a Chinese border outpost here in the 630s). According to legend, back in the 5th century, a Chinese princess, married to a Khotan prince, secretly took silkworm pupae from the Celestial Empire in her magnificent hairstyle. Thus, Khotan became the first center of sericulture outside China; it was from here that the secret of its production leaked to Persia and Byzantium.
In the 10th century, Khotan was dominated by Kashgar princes. During the periods of its greatest power, the rulers of Tibet also tried to subjugate the oasis. Marco Polo, who visited the city in 1274, admired the quality of local fabrics.
A long time ago, people noticed the ability of butterflies to secrete silk. That is why, to obtain silk, he domesticated silkworm about 5000 years ago.
This inconspicuous, thick, whitish butterfly, with a wingspan of up to 4-6 cm, which has lost the ability to fly, is the only domestic insect that is not found in nature in the wild. The silkworm is named mulberry because its caterpillars eat only the leaves of the mulberry tree, or mulberry.
It is believed that the silkworm once lived in the wild in the Himalayas. It was domesticated in China around 3000 BC. e. Now the silkworm serves the person who feeds it and takes care of it. It is bred in Japan, China, the countries of Indochina, Southern Europe, Brazil, Central Asia and the Caucasus.
Sericulture
Even mechanized silkworm farms have been created for silkworm breeding. There, from the females of this domestic butterfly they receive eggs called Greena. Caterpillars are hatched from the disinfected grains and fed with mulberry leaves on feeding shelves in specially equipped rooms. Before pupation, each caterpillar crawls onto the branches placed on it and spins a cocoon around itself, secreting a thin thread about 1000-1500 m long. The cocoon coils within 3 days. Inside it, the caterpillar turns into a pupa, which develops in about 10 days. In males, the content of mulberry in the cocoon is significantly (on average 20%) higher than in females. Therefore, the development of the silkworm is controlled and it is ensured that its offspring consist mainly of males. Material from the site
The finished cocoons are collected and treated with hot steam, and then silk threads are unwound from them using special machines. From 1 kg of cocoons, 90 g of light, durable natural silk are obtained.