SIXTH SEMESTER-SERICULTURE
Weekly Classroom Activities will be uploaded regularly
Theory
VIDEO POWER POINT PRESENTATION READING MATERIALS
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Cocoons in their fresh condition with live pupae cannot be stored for a long time as the living pupae are soon transformed into moths - generally within eight to ten days in a warm climate....
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The sericin or the silk gum present on the cocoon filament keeps them together compactly in the shell. This is softened with hot water or steam, so that the filament can be wound on the reel without
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After the cocoons are cooked either for the floating system or the sunken system, the cocoons have to be brushed for removing the surface floss layer of cocoons. The floss layer of the cocoon is entangled
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The silk filament or bave forming the cocoon though apparently single is actually composed of two filaments or brins which issue from a pair of silk glands of the silkworm and are stuck together and covered by silk
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Silk weaving has reached a very high standard of industrial efficiency. In fact, today a number of varieties of silk fabrics are produced on handlooms and sophisticated power looms. This requires different
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Throwing means twisting before weaving through series of operations. The term THROW means to twist or spin
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weaving is the interlacing of the two systems of yarns, which interlace at right angles to each other.
The lengthwise thread are called warp. Individually they are known as ends. The crosswise threads are called filling or weft |
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The process of eliminating the gum from the raw silk is known as degumming of silk.
Dyeing is defined as an operation or a series of operations by means of which uniform colour of a permanent character is produced on a substance. |
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There are two types of silk yarns used in the weaving sector. One is raw silk – which is comparable to filament yarn in synthetic textiles.
Second one is spun silk – which is comparable to staple fiber in synthetic textiles. |
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PRACTICALS
Ex. No. 1
Aim: To categorize different types of cocoons. Introduction: Generally every cocoon lot contains many types of defective cocoons like double, flimsy, melted, stained, urinated, etc. The production of such defective cocoons depending upon the method of rearing, climatic conditions during rearing and |
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Ex No 2
Aim: To determine the degree of drying in the given cocoon sample. Introduction: The process of killing the pupae and drying of cocoons is known as stifling of cocoons. Cocoons can be stifled by several methods but the popular methods in reeling industry are sun drying, steam stifling and hot air conditioning. Of these methods sun dried and hot air conditioned cocoons can be stored for |
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Ex. No. 3
Aim: To determine the pH of the reeling water samples using pH paper and pH meter. Introduction: pH of water indicates the hydrogen ion concentration in water. It is expressed as negative logarithm of hydrogen ion concentration in moles/liter at given temperature. The pH scale extends from zero (very acidic) to 14 (very alkaline) with 7 corresponding to |
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Ex. No. 4
Aim: To estimate the total alkalinity of the given reeling water sample. Introduction: Total alkalinity of water is the measure of water to neutralize a strong acid. The alkalinity of the water is generally due to the presence of salts of carbonate, bicarbonate, phosphate, borate, silicate etc., with hydrogen ion in the free state. However, most of the water is rich in carbonates and bicarbonates |
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Ex. No.5
Aim: To determine the cocoon weight, shell weight, shell per cent age and floss per cent age of the given cocoons. Introduction: Though the cocoon contains floss, shell, pupa and its larval skin, cocoon weight, shell weigh, shell percentage are the most important traits from the point of reelable silk. Therefore, determination of these commercial characters is the most important parameters to be considered for price fixation in |
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Ex. No. 6
Aim: To determine the cocoon weight, shell weight, shell per cent age and floss per cent age of the given cocoons. Introduction: Though the cocoon contains floss, shell, pupa and its larval skin, cocoon weight, shell weigh, shell percentage are the most important traits from the point of reelable silk. Therefore, determination of these commercial characters is the |
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Ex.No.7
Aim: To identify different textile fibers by physical and chemical tests. Introduction: The identification of textile fibers is an important step in textile industry. A number of methods |
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Ex. No. 8
Aim: To find out sericin content in the given raw silk sample. Introduction: Since the natural silk possesses colouring matter, wax, fat and inorganic materials and such materials should be removed from the raw silk yarn. Otherwise it leads to difficulties in dyeing. Though the cocoon contains floss, shell, pupa and its larval skin, cocoon weight, shell weigh, shell percentage are the |
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Ex. No. 9
Aim: To determine the bleaching loss in the given silk sample. Introduction: H2O2 is a soft chemical used as bleaching agent. It is an aqueous solution with 30-50% concentration. H2O2 becomes more stable in acidic media. The chemical reaction involves disassociation of H2O2 in the form of perhydroxyl ion in the alkaline media which further disassociates in to O, OH+ |
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Ex. No. 10
Aim: To get required colour on silk. Requirements: Heater, vessel, thermometer, balance, glass wares, degummed silk, different dye stuffs, glauber’s salt, acetic acid etc., Preparation of Dye Solution: In order to prepare 1% shade, dissolve exactly 1% of dye powder on the basis of silk weight in required amount of water. Make a clear paste without any dye granules before preparing final solution |
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Ex. No. 11
Aim: To identify wastes of silk industry. Introduction: Different types of silk wastes are identified by observing the characteristic features of each type. Apart from the defective cocoons, another grade of silk waste, which is a bye product of silk industry referred to floss |
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Ex. No. 12
Aim: To extract the oil in the given pupal sample. Introduction: The dried pupal powder contains water (11.1%), fat (29.57%), protein (48.98 %), glycogen (4.65%), chitin (3.35%), ash (2.17%), vitamins and others components (3.7%). The above data shows that the pupa is a very good source of fat and protein. The pupal oil extraction is very simple process. The dried and |
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VANYA SERICULTURE
POWER POINT PRESENTATION READING MATERIAL
In this topic, non mulberry food plants viz., T.arjuna, R. Communis and Macnilus bombycinat and Litsaea polyantha are explained.
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Tropical Silkworm
A. mylitta, (India) Temperate Silkworm A. proyli, (India) A. pernyi, (China, Russia) A. yamamai, (Japan) A. assamensis Philosamia ricini |
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Outdoor rearing ccount for losses of 50-55%, during the early instars.
Besides, the mortality from disease (35-40%). Losses can be substantially decreased by a more rational approach to rearing |
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The wild nature of the tropical tasar silkworm is reflected in its dis-uniform and erratic emergence, coupling, egg laying, hatching and other habits.
Selection of seed cocoons Healthy, well formed and tough cocoons are selected. Also, Stocks showing not more than 5-10% infection can be considered for seed. |
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Pathology - The scientific study of the nature of disease and its causes, processes, development, and consequences. Also called pathobiology.
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Sucking Pests:- Thrips, Aphids and Jassids cause damage to leaves of som and soalu and cause wilting of leaves. The initial symptoms are leaf margin rolling, followed by curling and wilting of leaves.
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