Issues associated with the elderly population of India
About Silkworms:
- The only food source for the caterpillars of these two species—also referred to as silkworms—is the leaves of mulberry plants (genus Morus).
- The domesticated moth extrudes a longer silk fibre to construct a larger cocoon that can reach 900 metres in length because it is significantly larger than its wild progenitor.
- However, its survival and procreation are entirely dependent upon human care.
- It has lost its ability to fly since domestication, and since it is no longer in need of camouflage, it has also lost the pigmentation of its caterpillar and adult stages.
Phytochemicals and flavonoids:
- Samia cynthia ricini, Antheraea assama, and Antheraea mylitta are the three species of moths that provide the “wild” silks, which include the muga, tasar, and eri silks.
- The caterpillars of these moths feed on a broader range of trees, and they are largely self-sufficient in their survival.
- About 30% of the silk produced in India is made from non-mulberry silks.
- In contrast to the mulberry silks, which have long, fine, and smooth threads, these silks have shorter, coarser, and harder threads.
- Brown-yellow cocoons are produced by the ancestor mulberry moth. On the other hand, the vivid colours of flesh, pink, pale green, deep green, yellow-red, and white are found in the cocoons of domesticated silk moths.
- Upon their emergence, human handlers likely chose the differently coloured cocoons with the intention of breeding them for coloured silks.
- We now understand that the pigments found on cocoons are produced by chemical substances called flavonoids and carotenoids, which are found in mulberry leaves.
- The chemicals are taken up and bound to the silk protein in the silk glands by the silkworms after they devour an abundance of leaves, absorb them in their midgut, and transfer them there via the hemolymph, the arthropod equivalent of blood.
- The silk proteins and related pigment are then spun out into a single fibre by mature caterpillars. To construct the cocoon, the caterpillar encircles itself with fibre.
Variant varieties:
- From the cocoon, the adult moth emerges. The fibre is broken throughout this process.
- Unhatched cocoons are used for reeling because superior quality silk is derived from an intact fibre.
- Mutations in the genes in charge of the absorption, transportation, and alteration of carotenoids and flavonoids cause the differently coloured cocoons.
- Scientists are now able to study the molecular basis of how artificial selection produced such spectacular diversity in a relatively short period of time—5,000 years—by utilising the mutant strains.
Aponttic-like gene:
- It is possible to create hybrid offspring through interbreeding domesticated and ancestral mulberry silk moths.
- The hybrid caterpillars produced melanin, just like their wild counterparts did.
- Still, when the B. When the apontic-like copy from Mandarina underwent mutation, the hybrid was unable to produce melanin.
- The same protein is produced by both apontic-like gene variants. Consequently, variations in the sequences that control when and where the gene is turned “on” or “off” were responsible for the differences between them.
To sum up:
- As far as domestication goes, silk is on par with golden retrievers, basmati rice, and Alphonso mangoes. Genetically identical hybrid silk moths that differ only in which of a gene’s two parental versions is inactivated—domesticated or ancestral—can now be created and compared by scientists thanks to technological advancements.
- This makes it possible for researchers to decipher all the crucial steps that culminated in the domestication of silk moths, gene by gene. Hopefully, we will be able to analyse domestication in dogs, rice, and mangoes using comparable techniques in the not too distant future.
