![]() ![]() About 2,000 to 3,000 cocoons are required to make 1 pound of silk (0.4 kg). The fibers are fine and lustrous, about 10 μm (0.0004 in) in diameter. The cocoon is made of a thread of raw silk from 300 to about 900 m (1,000 to 3,000 ft) long. Many other Lepidoptera produce cocoons, but only a few-the Bombycidae, in particular the genus Bombyx, and the Saturniidae, in particular the genus Antheraea-have been exploited for fabric production. The final molt from larva to pupa takes place within the cocoon, which provides a layer of protection during the vulnerable, almost motionless pupal state. The larvae then prepare to enter the pupal phase of their life cycle, and enclose themselves in a cocoon made up of raw silk produced by the salivary glands. After molting, the larval phase of the silkworms emerge white, naked, and with little horns on their backs.Īfter they have molted four times, their bodies become slightly yellow, and the skin becomes tighter. When the color of their heads turns darker, it indicates they are about to molt. ![]() They are not monophagous, since they can eat other species of Morus, as well as some other Moraceae, mostly Osage orange. They have a preference for white mulberry, having an attraction to the mulberry odorant cis-jasmone. Description and life cycle Larvae Įggs take about 14 days to hatch into larvae, which eat continuously. Their eggs typically hatch within 9 to 12 days, meaning there can be up to eight generations of larvae throughout the year. In addition, there are polyvoltine silkworms found only in the tropics. Bivoltine varieties are normally found in East Asia, and their accelerated breeding process is made possible by slightly warmer climates. Univoltine eggs must hibernate through the winter, ultimately cross-fertilizing in spring. Univoltine silkworms produce only one brood a season, and they are generally found in and around Europe. ![]() Mulberry silkworms can be divided into three major categories based on seasonal brood frequency. : 342Ĭompared to most members in the genus Bombyx, domestic silk moths have lost their color pigments as well as their ability to fly. mandarina can still breed and sometimes produce hybrids. Before then, the tools to manufacture quantities of silk thread had not been developed. Silk moths were unlikely to have been domestically bred before the Neolithic period. The domestic silk moth derives from Chinese rather than Japanese or Korean stock. The domestic silk moth was domesticated from the wild silk moth Bombyx mandarina, which has a range from northern India to northern China, Korea, Japan, and the far eastern regions of Russia. ![]() Sericulture, the practice of breeding silkworms for the production of raw silk, has been underway for at least 5,000 years in China, whence it spread to India, Korea, Nepal, Japan, and then the West. Wild silk moths (other species of Bombyx) are not as commercially viable in the production of silk. Domestic silk moths are entirely dependent on humans for reproduction, as a result of millennia of selective breeding. A silkworm's preferred food are white mulberry leaves, though they may eat other species of mulberry, and even leaves of other plants like the osage orange. The silkworm is of particular economic value, being a primary producer of silk. The silkworm is the larva (or caterpillar) of a silk moth. It is the closest relative of Bombyx mandarina, the wild silk moth. The domestic silk moth ( Bombyx mori) is an insect from the moth family Bombycidae. Bombyx arracanensis Moore & Hutton, 1862. ![]()
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