What does a silkworm look like and features of its activity
Natural fabrics have been the most popular for many centuries. Thanks to the silkworm, silk appeared. This fabric is loved by women of fashion for its delicate and smooth structure.
Content
What does a paired silkworm look like: photo
Description and origin
The silkworm is a butterfly belonging to the True silkworm family.
There is a version that silk was produced from an insect as early as 5000 BC. After a significant period of time, the production process has not changed much.
In the international classification, the insect is called "silk death". The main goal in production is to prevent butterflies from flying out of the cocoon - this contributes to the preservation of the silk thread. To do this, the pupa must die inside the cocoon, which is possible with the help of high temperature.
| Wingspan | The wingspan ranges from 40 - 60 mm. However, moths hardly fly. Males can fly a short distance when they mate. |
| Habitation and nutrition | Insects live on mulberry trees (mulberries). Many people love juicy and sweet mulberries. However, the silkworm only feeds on leaves. The larvae eat them all day long. This process is characterized by a loud sound. |
| Creation of a cocoon | After a period of pupation, caterpillars begin weaving a cocoon. At the heart of the cocoon is a continuous finest silk thread. Hue is pink, yellow, white, green. Mostly white is preferred. Certain species are bred to produce thread of that color. |
| Appearance | The moth is inconspicuous. It is similar to a large moth. The butterfly has large gray wings with traced dark streaks. The body is large with dense light villi. 2 long antennae on the head resemble scallops. |
| Larva | The larva is very small. The size is not more than 3 mm. Despite this, he eats leaves around the clock and gains weight. |
| Moulting process | Within a few days, molting occurs 4 times and a beautiful caterpillar is obtained, which has a pearl color. Up to 8 cm long, 1 cm thick. Weight does not exceed 5 g. |
| Thread creation | There are 2 pairs of well-developed jaws on the head. Special glands end in the oral cavity with an opening. A special liquid comes out of the hole. In the air, the liquid solidifies and the famous silk thread appears. |
| Varieties | The breed is wild and domesticated. In the wild, all stages pass. At home, they are killed in a cocoon. |
For caterpillars, silk thread is a material in the construction of a cocoon. The cocoon can be from 1 cm to 6 cm. The shape is round or oval.
Habitat
The homeland of the insect is China. Wild moths lived in mulberry groves for more than 3000 years BC. Later they began to domesticate and distribute in other countries. The south of the Primorsky Territory of the Russian Federation and the northern regions of China are inhabited by wild breeds of butterflies.
The habitat is associated with silk production. Insects are imported to regions with a warm and moderately humid climate. A sudden change in temperature is not allowed. Abundant vegetation is welcome.
The main area is India and China. They account for 60% of all silk. Also, production is an important industry in the economy of countries such as:
- Japan;
- Brazil;
- France;
- Italy.
caterpillar diet
The silkworm loves mulberry leaves.
Mulberry leaves are the main diet. The mulberry tree has 17 varieties. The tree is very tricky.
The juicy fruit looks like a wild raspberry or blackberry. Fruits are white, red, black. The most fragrant are black and red fruits. They are added to desserts, pastries, wine. But caterpillars do not eat fruits, but only greens.
Silk growers plant plants and create suitable conditions. Farms are supplied with constantly crushed leaves. It is in the leaves that the best components for the production of valuable silk threads are found.
Life
Silk production played a significant role in the way of life. Wild insects flew well. Their large wings could lift into the air and move a decent distance.
Moths are viable. However, evolution has greatly influenced them. The males are active. It is noted that the adult does not eat anything. This is the main difference from a caterpillar with powerful jaws, which absorbs food without stopping.
Reproduction
The silkworm is classified as a paired insect capable of reproduction. Some species breed once a year, others - 1 times. The mating period is characterized by short flights of males. Natural conditions contribute to the fertilization of several females by one male.
Stages of silkworm development
Under artificial conditions, insects are placed in a separate bag and left for 3-4 days for the female to lay eggs. One clutch contains 300 - 800 eggs.
The number and size is affected by the breed and breeding of the individual. In order for the worms to hatch, moisture and a temperature of 23 to 25 degrees Celsius are needed. On mulberry farms, employees create conditions in incubators.
A tiny larva emerges from each egg. She has a good appetite. A day after birth, he can eat 2 times more food than on the previous day. A plentiful diet contributes to the rapid maturation of the caterpillar.
On the fifth day, food intake is stopped. There is a fading to shed the first skin the next day. Then eat again for 4 days. Before the next cycle of molting, it stops eating. These actions are repeated 4 times.
The end of the molt implies the formation of an apparatus for the production of threads. The next stage is cocooning. The caterpillar stops eating. A thin thread is poured out and pupation begins. She wraps herself in it. At the same time, the head is actively working.
Pupation takes up to 4 days. The insect spends the thread within 0,8 - 1,5 km. Having formed a cocoon, she falls asleep. After 3 weeks, the chrysalis turns into a butterfly and can emerge from the cocoon.
In this regard, the life cycle is interrupted during this period. To do this, use high temperatures up to 100 degrees. The larvae die, but the cocoons remain intact.
Individuals are left alive in order to further reproduce. Residents of Korea and China feed on dead larvae after unwinding.
Natural enemies
In the wild, the insect is the diet for:
- birds
- insectivorous animals;
- parasitic insects.
Insectivores and birds consume adults and caterpillars. The most dangerous are tahini and urchins.. The hedgehog lays its eggs inside or on the worm. There is a development of dangerous larvae that kill the silkworm. The surviving infected individual gives offspring already sick.
Pebrin disease is a deadly threat. It is caused by pathogenic microorganisms. But modern silkworm breeders manage to cope with the pathogen.
Interesting Facts
It is worth noting that a dead chrysalis is a valuable product that can be eaten. Natural silk thread is classified as a protein product. It can be dissolved by aggressive chemical detergents. This is taken into account when caring for a silk product.
The exceptional strength of the threads is suitable even for the production of body armor.
In nature, insects fight on their own with enemies. They eat a plant containing toxic alkaloids. Alkaloids are capable of destroying parasite larvae.
Conclusion
Silk is the lightest and most beautiful material for sewing things and textiles. The cultivation of silkworm is very important for the economy of many countries in connection with the export of valuable fabric.
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