TABLE OF CONTENTS
List of Plates
List of Tables
List of Acronymsv
2. Importance of Sericigenous Resources and Conservation
3. Description of the Extent of Sericigenous Resources Biodiversity Conservation and Utilization in the world
4. General Analysis of the Extent of Sericigenous Resources Biodiversity Conservation and Utilization in the world
5. Actualization: Practical case studies of Bombyx mori Conservation and Utilization in China, India and Uganda
6. Actualization: Practical Case Studies of Wild Silkworm Conservation and Utilization in the world
7. Discussions: Advantages and Disadvantages of Sericigenous Resources Biodiversity Conservation and Utilization
8. General Recommendations.
List of Plates
Plate 1: Bombyx mori silkworms feeding on mulberry leaves
Plate II: Bombyx mori silkworm and the cocoon..
Plate 3: Muga silkworms on a som tree
Plate IV: Anaphe reticulate silkworms on bridelia tree leaves
Plate 5: (a): Adult Antheraea polyphemus silkworm
(b): Adult female and male Antheraea polyphemus silkworms mating
(c): Eggs of Antheraea polyphemus silkworm
(d): First instar larva of Antheraea polyphemus silkworm
(e): Second instar larva of Antheraea polyphemus silkworm
(f): Third instar larva of Antheraea polyphemus silkworm
(g): Fourth instar larva of Antheraea polyphemus silkworm
(h): Fifth instar larva of Antheraea polyphemus silkworm
(i): Cocoon of Antheraea polyphemus silkworm
Plate VI: Leaves of Morus species
Plate 7: Mulberry plantation established for Bombyx mori silkworm rearing in India
Plate: VIII (a): Bombyx mori silkworm rearing in India
(b): Bombyx mori cocoons in the market in India
(c): Decorations from silkworm cocoons
(d): Silk yarn ready for weaving into cloth
Plate 9: Silk garments from Uganda
List of Tables
Table 1: Some commercially important wild silk moths and their Taxonomic Families, Silk Description and Geographical Distribution
Table II: Some important potential wild silk moths and their Taxonomic Families and Geographical Distribution
Table 3: Biodiversity of Antheraea species in the world
Table IV: Biodiversity of food plants of the tropical tasar silk moth, Antheraea paphia.
Table 5: Chronology of the conservation and utilization of Bombyx mori in China
Table VI: Chronology of the conservation and utilization of Bombyx mori in India
Table 7: Chronology of the conservation and utilization of Bombyx mori in Uganda
List of Acronyms
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Sericigenous fauna are animals that are capable of producing a natural and highly valued fibre called silk. According to Prasad et al. (2010), the word “Sericigenous” is derived from a Greek word “Seri” meaning Silk. Sericigenous fauna have a wide biodiversity, which can be primarily categorized as insect and non-insect groups. The non-insect group includes the Adriatic mussel (seashell Pinna nobilis and related species which produce silk referred to as sea silk) and a Madagascarian spider. The silk of non insect origin is of no importance to textile market as its use is limited in the area of optical instruments. The insect group includes all the silk spinning insects whether foraging on mulberry plant or other non mulberry plants; their silk is the one used in making garments. Therefore, Sericigenous resources include the silk producing animals and the associated plants they feed on. This paper reviews the sericigenous resources biodiversity that have so far been identified and documented and the efforts that have been put in place to conserve and utilize them sustainably. The emphasis here is laid on the Sericigenous insects, the silk moths, and their food plants.
Importance of Sericigenous Resources and Conservation
Sericigenous resources are of great use and benefit to man. Silk is a precious commodity; it is generally used for making expensive and very impressive looking garments (textiles). It is actually called the queen of textiles because of its glittering luster, soft feeling, elegance, durability and tensile properties, unmatched by other textiles whether natural or artificial. Silk can be categorized according to the type of food plant the silkworms feed on. For example, the mulberry silk is produced by the fully domesticated Bombyx mori which feeds on mulberry plant while the non mulberry silks are categorized as muga, tropical tasar, temperate/oak tasar and eri silks, depending on the type of the food plant and also the species of the silkworm, and the silkworms are not fully domesticated yet, like the Bombyx mori. Therefore the muga, tropical tasar, temperate/oak tasar and eri silks are referred to as wild silks. Sericigenous resources are also used for scientific research and development. For example, the silk moth Bombyx mori and its food plant, the mulberry plant, Morus species, have been extensively researched, domesticated and developed, over many years, for commercial silk production, a practice called sericulture (Prasad et al., 2010).
Description of the Extent of Sericigenous Resources Biodiversity Conservation and Utilization in the world
There are more than 500 species of wild silkworms in the world, but so far only one fully domesticated silkworm species, Bombyx mori L. Only a few of the wild silkworms are of commercial importance to produce cloth (Table 1). The exploitation of commercially important wild silkworms is called wild silk farming. Wild silkworms usually produce a tougher and rougher silk than that from domesticated Bombyx mori silkworms. Wild silks are usually harvested after the moths have left the cocoons, cutting the threads in the process so that there is not one long thread as with domesticated silkworms. Wild silks tend to be more difficult to bleach and dye than silk from Bombyx mori, but most have naturally attractive colours, particularly the rich golden sheen of the silk produced by the muga silkworm from Assam (India) and is often known as Assam silk. The cocoon shells of wild silk moths are toughened or stabilized either by tanning (cross-linking) or by mineral reinforcements (e.g. calcium oxalate). A new method has been developed, demineralizing, which can remove the mineral reinforcements present in wild silks and enables wet reeling like the commercial silk worm Bombyx mori. Although wild silk in general constitutes only about 10% of the total silk output in the world and is being dominated by mulberry silk (Braja, 1999), it can still sustain strong local and international market niches if developed, because of its natural attractive colours, durability, own feel and special appeal (Prasad et al., 2010).
- Quote paper
- BSc, MS (Candidate) Cosmas Alfred Butele (Author), 2012, Sericulture. The Extent of the Conservation and Utilization of Sericigenous Resources Biodiversity in the World, Munich, GRIN Verlag, https://www.grin.com/document/207282