Here, the shell is loosely spun in layers and has a low silk content. These cocoons are easily overcooked and produce waste
Malformed Cocoons
These are abnormally shaped cocoons, which may arise from species variation. This defect may be due to racial characteristics and breeding with mulberry leaves stained with agrochemicals.
Printed Cocoons
This defect may happen due to improper mounting frames; these are also called scaffold pressed cocoons.
Outside Stained Cocoons
These are recognized by a rusty colour spot on the cocoon shell caused by absorption of intestinal fluid/urine of the mature worm formed during mounting. Reelability is very poor in this case.
Inside Stained Cocoons | Dead Cocoon
Dead cocoons are also known as melted cocoons. In this case, the pupa is dead and sticks to the inside shell of the cocoon causing a stain.
Melted cocoons are called mutes because they do not make a sound when shaken. These cocoons are difficult to process and will result in silk, which is dull in colour.
Melted cocoons are called mutes because they do not make a sound when shaken. These cocoons are difficult to process and will result in silk, which is dull in colour.
Defective Cocoons like Double Cocoon
A double cocoon is spun by two worms, producing a filament, which does not unwind smoothly and tangles easily. As these cannot be reeled along with normal cocoons, double cocoons are used for manufacture of a coarse, non-uniform, stubby yarn called "doupion".
Double cocoons may be caused by crowded mounting conditions, high temperatures, high humidity and mutation of silk species.
Double cocoons may be caused by crowded mounting conditions, high temperatures, high humidity and mutation of silk species.
Different Types of Cocoons
When Cocoons are sold at the market, price is assessed on the basis of cocoon quality. This is judged by grading shell percent, filament length, reelability and the percentage of defective cocoons. If the percentage of defective cocoons is high, the price will be affected.
Transport of Fresh Cocoons
- After proper harvesting and removal of diseased or damaged cocoons, the fresh cocoons are taken to the market. For short distances, the farmer carries the cocoons in bamboo baskets or jut bags on his head or by bicycle. If the distance is longer, cocoons are transported in a van or a bus. Caution should be exercised when loading fresh cocoons on to the van to ensure that containers are loosely packed in tiers to avoid damage. Vibration and shock during long trips can spoil fresh cocoons. Cocoon quality is affected by steam produced while being transferred in a bag or basket. If there are defective cocoons fresh cocoon quality will be harmed.
- While it is advisable to avoid carrying cocoons over long distances, there are steps, which preserve silk reelability. First use of P.V.C. containers with 15 kgs capacity is recommended. Shock absorbers, such as sponge can prevent damage over long distances. To minimize the risk of heat deterioration, shipping should take place only during the night or early morning. Ideally, the fresh cocoons should arrive at the stifling unit within two to three days after harvest.
Factors Influencing Cocoon Quality
This section presents the measures to be taken during silkworm rearing and mounting to obtain a better quality of cocoons with higher silk content, longer filament, better reelability and lower percentage of defective cocoons.
Temperature and Humidity During Mounting
Maintain temperatures at or near 25ºC and relative humidity around 65 percent for silkworms to spin good quality cocoons with a high reelability.
Mounting Device
Although different mount practices are employed among producer countries, rotary mounting frames provide good ventilation. The result is improved reelability of cocoons. Harvesting and Handling of Fresh Cocoons
Cocoons should be harvested only following complete pupation. In practice, the appropriate harvesting day would be the fifth day in tropical countries, and the seventh or eighth day in temperate countries, from the mounting date. If premature harvesting takes place, the silkworm will still be in its larval stage, weigh more, have fragile skin, and could likely be crushed, which would cause stains to the cocoon during handling and transportation.
Cocoon Quality
A Series of natural circumstances will produce variations in cocoon quality. Some of the most noteworthy include:
Differences in cocoon quality in the same batch
Differences in cocoons produced in the same location by different farmers who have reared the same speciesSeasonal influences. In Japan for example, cocoons produced in the spring and late autumn are higher in quality than those in early autumn and summer
Environmental conditions affect cocoon reelability such as temperature and humidity
Processing technique in reeling will impact reeling efficiency as well as raw silk quality
Bivoltine cocoons are superior quality compared to multivoltine silkworm species traditional farmed in tropical zones.
Recent silkworm cultivation now develops cross-breeds of multivoltine with bivoltine silkworms as a strategy to improve overall cocoon quality.
Oxidation Effect on Silk
- Reports regarding the oxidation of proteins are rather meagre since the reactions are very complex. Oxidizing agents may attack proteins in three possible points
- At the side chains
- At the N-terminal residues
- At the peptide bonds of adjacent amino groups.
Degradation by Acids, Alkalis on Silk
- Treatment of silk fibres with acid or alkaline substances causes hydrolysis of the peptide linkages. The degree of hydrolysis is based on the pH factor, which is at minimum between 4 and 8. Degradation of the fibre is exhibited by loss of tensile strength or change in the viscosity of the solution.
Nitric acid readily decomposes fibroin, due to its powerful oxidizing properties and concurrently causes nitration of the benzene nuclei. Organic acids have few effects at room temperature when diluted, but in a concentrated form fibroin may be dissolved, along with a certain amount of decomposition.
Effect of Heat on Silk
If white silk is heated in an oven at 110ºC for 15 minutes, it begins to turn yellow. At 170ºC, silk disintegrates and at its burning points releases an empyreumatic odour.
Action of Water on Silk
Silk is a highly absorbent fibre, which readily becomes impregnated with water. Water, however, does not permanently affect silk fibre. Silk strength decreases about 20 percent when wet and regains its original strength after drying. The fibre expands but does not dissolve when steeped in warm water. Note that the fibre will also absorb dissolved substances present in water. This is the reason that special attention is given to the quality of the water utilized for reeling, washing, dyeing or finishing.
Electrical Properties of Slik
Silk is a poor conductor of electricity and accumulates a static charge from friction. This trait can render it difficult to handle in the manufacturing process. This static charge can be dissipated by high humidity or by maintaining a R.H. of 65 percent at 25ºC. Based on its insulating properties, silk is used extensively for covering wire in electrical equipment.
Effect of Light on Silk
Continuous exposure to light weakens silk faster than cotton or wool. Raw silk is more resistant to light than degummed silk. It is advised that silk drapery and upholstery fabrics be protected from direct exposure to the light.
Hygroscopic Nature of Silk
- Denier=Fiber Weight(g)/Fiber Length(m) *9000
Tenacity and Elongation of Silk
Tenacity indicates the quantity of weight a given fibre can support before breaking. the typical tenacity of a bave is 3.6 to 4.8 g per denier . Degummed silk has greater tenacity than raw silk. Elongation defines the length to which a fibre may be stretched before breaking. Raw silk has an elongation of 18 to 23 percent of its original length. Excess moisture increases the elongation of silk, but decreases its tenacity.
Specific Gravity of Silk
The bave specific gravity on average of sericin and fibroin measures from 1.32 to 1.40. Generally, the specific gravity of sericin is slightly higher than that of fibroin
Features of Silk, Properties Silk, Bombyx Mori Silk
- The silk of Bombyx mori is composed of the proteins fibroin and sericin, matter such as fats, wax, sand pigments plus minerals.
- Fibroin in the Bombyx mori comprises a high content of the amino acids glycine and alanine, 42.8 g and 32.4 g respectively
- The key amino acids in sericin are serine (30.1 g), threonine (8.5 g), aspartic acid (16.8 g) and glutamic acid (10.1 g)
Sericin is a complex protein composed of three distinct components (I, II and III) of which sericin III is the interior layer directly adjacent to the fibroin core. The sericin I outer lay is the most soluble of the three constituents, while sericin III is difficult to dissolve. Viewed as a cross section, the brins have the appearance of equilateral triangles with rounded corners that face each other at their respective bases.
When the brin is crushed, it splinters into numerous minute fibrils revealing the actual structure of the brins. The thickness of each fibril is less than one micron and they are parallel to the axis of the fibre. A single fibril contains many microfibrils which, when examined with an electron microscope, have a diameter of approximately 100 Å per microfibril. Microfibrils contain micelles, which are separated into crystalline and amorphous segments.
Composition of Cocoon Shell
The silk filament forming the cocoon shell is composed of two brins (proteins) named fibroin and covered by silk gum or sericin. The amount of sericin ranges from 19 to 28 percent according to the type of cocoon.
The composition of the cocoon shell is given below:
The composition of the cocoon shell is given below:
- Fibroin -- 72-81 percent
- Sericin -- 19-28 percent
- Fat and wax -- 0.8-1.0 percent
- Colouring matter and ash -- 1.0-1.4 percent
Composition of a Whole Cocoon
The composition of the whole cocoon is defined as the cocoon shell, cocoon pupa and cast off skin . The cocoon pupa makes up the largest portion of its weight. Note that much of the cocoon content is water. Therefore it is necessary to remove the water to improve the cocoon filament for reeling and to better preserve the cocoon over a long period.
Lousiness in Silk
Hair-like projections in the silk fibre are called Lousiness. Lousiness is more prevalent in baves produced by silkworms, which have been overfed in their fifth stage of rearing. Lousiness is found less in breeds of silkworms, which spin finer bave. Another factor promoting lousiness is mounting of over-mature larvae. This defect poses serious problems to silk fabric manufacturers, in particular those producers of smooth satin and necktie materials. When fabrics woven with these defects are dyed, it looks as if the fabric is covered with dust or is a paler shade than the rest. In fact, the protruding fibril is more transparent and has a lesser capacity to absorb dyes.
Cocoon Defects
A series of minor defects may be found in cocoon filament such as loops, split-ends, fuzziness, nibs and hairiness . While these defects are observed among silkworm varieties, mounting conditions seem to contribute to their incidence. These filament defects directly affect raw silk quality.
Size of Cocoon Filament
The measure denier expresses the size of silk thread. A denier is the weight of 450 m length of silk thread divided into 0.05 g units. The diameter of the bave is not constant throughout its length, instead changes according to its position in the bave shell. At the coarsest section of cocoon filament from 200 to 300 meters, the denier increases. Once more these dimensions become finer and finer as the process approaches the inside layer . The average diameter of cocoon filament is 15 to 20 microns for the univoltine and bivoltine species.
Cocoon Reelability
Reelability is defined as the fitness of cocoons for economically feasible reeling. Industry practice measured the case with which the cocoon yields the bave in reeling. Poor reelability causes a variety of production problems such as halts in production due to filament breakage and high degrees of waste product. Reelability is greatly affected by careful action during cocoon spinning, drying, storage, pre-processing, reeling machine efficiency and operator skill. Recent statistics show an average reelability of percent for good cocoon varieties. The measured range is from 40 to 80 percent with serious deviations depending on the type of cocoon. Note that stained cocoons generally have poor reelability.
Cocoon Filament Length
Equally important as the percentage of silk shell is measuring the length of the bave contained in the shell. The factor determines the workload, rate of production, evenness of the silk thread and the dynamometric properties of the output. The length of cocoon filament corresponds to the varieties of silkworms. Range of total length is from 600 to 1 500 m of which 80 percent is reelable while the remainder is removed as waste.
Raw Silk Percentage of Cocoon
This index is the most important for the value of the cocoon as it has a direct impact on both the market price of cocoons and the production costs of raw silk. The normal range is 65 to 84 percent for the weight of the cocoon shell and 12 to 20 percent for the weight of the whole fresh cocoon.
Coccon Shell Percentage
As the entire cocoon including the pupa is sold as part of the raw material, it is essential to quantify the ratio of the weight of the silk shell versus the weight of the cocoon. This is calculated in the formula.This value gives a satisfactory indication of the amount of raw silk that can be reeled from a given quantity of fresh cocoons under transaction. The calculation assists in estimating the raw silk yield of the cocoon and in deriving an appropriate price for the cocoons. The percentage will change based on the breed of the silkworms, rearing and mounting conditions. Percentage rates are altered based on the age of the cocoons (see cocoon weight) as the pupa loses weight as metamorphosis continues. In newly evolved hybrids, recorded percentages are 19 to 25 percent, where male cocoons are higher than female cocoons.
Cocoon Hardness or Cocoon Compactness
Cocoon hardness correlates to shell texture and is affected by cocoon spinning conditions. For instance low humidity during the mounting period makes the cocoon layer soft, while high humidity makes it hard. The degree of hardness also influences air and water permeability of cocoons during boiling. A hard shell typically reduces reelability (during the cocoon reeling process), while a soft-shell may multiply raw silk defects. In short, moderate humidity is preferred for good quality cocoons
Cocoon Thickness | Weight of Cocoon Shell
The thickness of the cocoon shell is not constant and changes according to its three sections. The central constricted part of the cocoon is the thickest segment, while the dimensions of the expanded portions of the head are 80 to 90 percent of the central constricted . The weight of the silk shell is the most consequential factor as this measure forecasts raw silk yield. As with other characteristics introduced in this chapter, shell weight differs in correspondence to varieties of silkworms. Further, weight is also influenced by the type of technology used for rearing and mounting. In practice, uni and bivoltine species produce heavier shell weights than multivoltine species.
Cocoon Weight
The most significant commercial feature of cocoons is weight. Cocoons are sold in the marketplace based on weight as this index signals the approximate quantity of raw silk that can be reeled. The whole weight of a single cocoon is influenced by silkworm species, rearing season and harvest conditions. Pure breeds range from 2.2 to 1.5 g, while hybrid breeds weight from 2.5 to 1.8 g. In nature, the weight of a fresh cocoon does not remain constant but instead continues diminishing until the pupae transforms into a mother and emerges from the cocoon. This weight occurs gradually as moisture evaporates from the body of the pupae and as fat is consumed during the metamorphosis process .
Cocoon Size
Cocoon size or volume is a critical characteristic when evaluating raw materials. The size of the cocoon differs according to silkworm variety, rearing season and harvesting conditions. The number of cocoons per litre, ranging between 60 and 100 in bivoltine species calculates size. Multivoltine species measure considerably higher.
Cocoon Wrinkles
The deflossed cocoon has many wrinkles on its surface. Wrinkles are coarser on the outer layer than within the interior layer. The outline of the wrinkle is not uniform, but various according to species and breeding conditions. Spinning employs high temperature and low humidity settings, which render fine wrinkles or cotton-like textures of, cocoon layers. These provisions discourage the agglutination of the baves resulting from accelerated drying. It is recognized that coarse wrinkled cocoons reel poorly.
Cocoon Shape
Cocoon shape, as colour, is peculiar to the given species. At the same time shape can be affected by the execution of the mounting process , especially during the cocoon spinning stage. Generally, the Japanese species is peanut-shaped, the Chinese elliptical, European a longer elliptical and the polyvoltine species spindle-like in appearance. Hybrid cocoons assume a shape midway between the parents for example, the case of a longer ellipsoid or shallowly enclosed peanut form . The shape of cocoons assists in identifying the variety of species plus evaluating reelability .
Cocoon Color
Color is a characteristic particular to the species. It is the presence of pigments in the sericin layers, which cause the colour. This colour is not permanent and washes away with the sericin during the degumming process . There are diverse hues of colour including but limited to white, yellow, yellowish green and golden yellow.
Physical Properties of Cocoon
The silk glands of the Bombyx mori are structured like tubes consisting of a Posterior, Middle and Anterior section. The Posterior is long and thin. The Middle is short with a diameter measuring 3-4 mm. The Anterior is extremely thin, leading to the spinneret in the head of the larvae from which the silk is excreted.
Fibroin is secreted in the Posterior and transferred by peristalsis to the Middle section, which acts as a reservoir. Here it is stored as a viscous aqueous solution until required for spinning. The majority of the sericin is created within the walls of the Middle section. In fact, these two proteins are reserved side by side in the Middle section without mixing one into the other. The fibroin core is covered with a layer of sericin and the secretions from the two proteins join at the junctions where the sericin is fused into one layer. The Filipis glands discharge a liquid protein. To form its cocoon, the silkworm draws out the thread of liquid protein and internally adds layer after layer to complete this protective covering.
Fibroin is secreted in the Posterior and transferred by peristalsis to the Middle section, which acts as a reservoir. Here it is stored as a viscous aqueous solution until required for spinning. The majority of the sericin is created within the walls of the Middle section. In fact, these two proteins are reserved side by side in the Middle section without mixing one into the other. The fibroin core is covered with a layer of sericin and the secretions from the two proteins join at the junctions where the sericin is fused into one layer. The Filipis glands discharge a liquid protein. To form its cocoon, the silkworm draws out the thread of liquid protein and internally adds layer after layer to complete this protective covering.
Types Of Mulberry Leaf Harvesting Techniques
Shoot Harvest
- Individual leaves are plucked upto 3rd age of the worms . Thereafter shoot harvest can be done stepwise downwards.
Leaf Plucking
- In this method leaves are harvested by plucking throughout the year.1st bottom pruning should be given after 3rd harvest i.e., in October/November and second after taking sixth crop in June / July.. In both the systems of harvest, it is necessary to maintain a stump height of 8" - 10" above the ground level. Pruning should be done with a sharp sickle / pruning saw without damaging the stem or bark.
Selection of Mulberry Seed
- Mulberry is a perennial Plant and it gives leaf yield for a period of 10 to 15 years. Therefore it is desirable to select high yielding variety of mulberry such as V1, S-Series, M5 etc.
Season for Mulberry Plantation
- Plantation is to be taken up during June -July months after the onset of monsoon.
Irrigation
- Irrigation is to be provided once in a week or 10 days depending on nature of the soil conditions.
Recommended Dosage of Manure
- Minimum of 20 Mt. / acre of farm yard manure is recommended.
Recommended Dosage of Chemical Fertilizers
- 28 kgs of Nitrogen, 12 kgs of Potassium and 12 kgs of Phosphorus is recommended / acre to apply after every shoot harvesting
Separate Chawkie Garden
- To harvest good cocoon crop care should be taken during Chawkie silk worm rearing by feeding quality leaf. Therefore it is recommended to raise separate Chawkie garden of 10-20 cents with S-36 variety of mulberry.
Maintenance of Mulberry Garden
- 1st year
- After 3 months of planting 50 kg N + 50 kg P + 50 Kg K per hectare should be applied in the form of complex fertilizer after weeding.
- Irrigate the plantation as and when necessary.
- 1st harvest can be taken 6 months after planting by leaf picking.
- Second dose of 50 Kg N/ha should be applied 3 weeks after 1st leaf harvest.
- Two more crops can be taken by leaf picking at an interval of 3 months.
2nd year onwards
- Irrigation
- Loamy soils - once in 10 days
- Clayey soils - once in 15 days.
- 1 ½ to 2 acre inch water should be provided per irrigation
Intercultural Operations
- It should be done as and when necessary by manual digging and weeding.
- Manure and Fertilizer Schedule
- Farm Yard Manure must be applied in June / July following pruning.
- Chemical fertilizers should be applied 3 weeks after every pruning / leaf harvest as per the schedule given below.
- Shedule Of Operations For Maintenance Of Mulberry Garden Under Irrigated Condition With Shoot Harvest System
- 1st pruning combining harvest With the commencement of SouthWest mansoon rain ( Early June)
- 1st weeding and intercultivation Within a week after pruning ( 2nd week of June )
- Application of FYM / compost 20 tonnes/ha and incorporation of the Same Within a fortnight after pruning (Mid June )
- 1st dose of fertilizer application Within a month after pruning ( Early July )
- 1st shoot harvest By pruning ( Mid August )
- 2nd weeding and intercultivation Within a week of first harvest ( 2nd fortnight of August )
- 2nd dose of fertilizer application Within a month of first harvest ( Mid September )
- 2nd shoot harvest By pruning ( Early November )
- 3rd weeding and intercultivation Within a week of 2nd harvest ( 2nd week of November )
- 3rd dose of fertilizer application Within a month of 2nd harvest (1st week of December )
- 3rd shoot harvest By pruning ( Mid January )
- 4th weeding and intercultivation Within a week of 3rd harvest ( 3rd week of January )
- 4th dose of fertilizer application Within a month of 3d harvest ( Mid February )
- 4th shoot harvest By pruning ( Late March )
- 5th weeding and intercultivation Within a week of 4th harvest ( 1st week of April )
- 5th dose of fertilizer application Within a month of 4th harvest ( Late April )
- 5th shoot harvest By pruning ( Early June )
- Schedule Of Operations For Maintenance Of Mulberry Garden Under Irrigated Condition With Leaf Harvest System
- 1st bottom pruning With the commencement of South West mansoon ( Early June)
- 1st weeding and intercultivation Within a week after pruning ( 2nd week of June )
- Application of FYM / compost 20 tonnes/ha and incorporation of the same Within a fortnight after pruning (3rd week of June )
- 1st dose of fertilizer application Within a month after pruning (Early July )
- 1st harvest of leaf By leaf picking ( Mid August )
- 2nd weeding and intercultivation Within a week of first leaf harvest (3rd week of August )
- 2nd dose of fertilizer application Within three weeks of first leaf harvest ( 2nd week of September )
- 2nd harvest of leaf By leaf picking ( Early October 9 )
- 3rd dose of fertilizer application Within 3 weeks of 2nd leaf harvest ( 4th week of October )
- 3rd harvest of leaf By leaf picking ( Late November )
- 2nd bottom pruning Immediately after 3rd leaf harvest (Late November )
- 3rd weeding and intercultivation Within a week after 2nd bottom pruning ( 1st week of December )
- 4th dose of fertilizer application Within a month after 2nd pruning (3rd week of December )
- 4th harvest of leaf By leaf picking ( Early February )
- 5th dose of fertilizer application Within 3 weeks after 4th leaf harvest ( 4th week of February)
- 5th harvest of leaf By leaf picking ( 1st week of April )
Calender Of Cultural Operations For Chawki Mulberry Garden
- 0 Days-- Prune all the plants at 20-25 cm above the ground level
- 1-2 Days--Maintain 10-12 shoots per plant. Remove dead portion of the shoots
- 3-4 Days--Apply FYM @ 5MT/ha/crop and mix well with soil by digging or ploughing.
- 5 Days--Prepare ridge and furrow
- 6 Days--Irrigation
- 10 Days--Irrigation
- 14 Days--Apply chemical fertilizers NPK @ 32.5:17.5:17.5 kg/ha/crop. (Ammonium Sulphate for N, Single Super Phosphate for P and Muriate of Potash for K) irrigate immediately after application
- 18 Days--Irrigate at an interval of 4 days
- 25 Days--Spray " Seriboost" 2.5ml/lt of water
- 28 Days--Remove week shoots
- 32 Spray " Seriboost" 2.5ml/lt of water
- 35 Days--Brushing and leaf harvesting
- 36-45 Days--Harvest leaf by picking and chawkie rearing
- 46-48 Days--Top clipping, shoot thinning, application of FYM @ 5MT/ha/crop digging, ridge furrow making and irrigation
- 48 Days--Apply FYM @ MT/ha/crop and mix well with soil by digging or ploughing
- 51 Days--Apply chemical fertilizer NPK @ 32.5:17.5:17.5 kg/ha/crop. (Ammonium Sulphate for N, Single Super Phosphate for P and Muriate of Potash for K) Irrigate immediately after application
- 60 Days--Spray " Seriboost" 2.5ml/lt of water
- 67 Days--Spray " Seriboost" 2.5ml/lt of water
- 72 Days--Brushing
- 73-78 Days--Chawkie rearing by using shootlets
Mulberry Varieties
Most of the sericulturists are traditionally practicing local mulberry ( Mysore local) varieties for plantation which gives low leaf yield and the low quality. Central Sericultural Research and Training Institute, Mysore and Regional Sericultural Research Station, Anantapur District have evolved following High yielding mulberry varieties.
- Ananta
- V-1
- S13
- S30
- S36
- S54
Ananta
- This high yielding mulberry variety developed at Regional Sericultural Research Station, Anantapur. It is drought resistant. Leaves are very big in size with light green in color. The leaves are succulent and good in quality. The leaves can be fed to both Chawkie and Late age silkworms. This is pest and disease resistant and yields more during summer. With 2' X 2' spacing, this variety gives around 65 to 70 tonnes of leaf per hectare per year.
M-5 or V-1 Variety
- This hybrid variety is developed by Central Sericultural Research and Training Institute, Mysore with combination of S30 and Ber C 776. The nutritious dark green boat shaped leaves are thick and shiny in nature. The branches grow long and straight. When grown under irrigated condition with 2' X 2' spacing the leaf yields 55 tonnes per hectare per year. Convenient to feed all stages of silkworms.
S 13 Variety
- This variety is drought resistant. The branches grow bushy and straight. The leaves are dark green in colour. When grown under irrigated condition, the leaf yields 48 tonnes per hectare per year. The leaves are succulent and good quality can be fed to both Chawkie and late age worms
S 30 Variety
- The leaves are boat shaped, succulent, shiny and green in colour. Branches grow straight. When grown under irrigated condition the leaf yields 36 tonnes per hectare per year. The leaves can be conveniently fed to both Chawkie and late age silkworm.
S 36 Variety
- The light green coloured leaves are big and succulent. The branches grow straight. Convenient to feed all stages of silkworms. When grown under irrigated condition the leaf yield will be 45 tonnes per hectare per year.
S 54 Variety
- The leaves are dark green in colour, succulent and big. The branches are bushy and will not grow tall, hence wider spacing is required for plantation. When grown under irrigated condition the leaf yield will be 39 tonnes per hectare per year. Convenient to feed all stages of silkworms.
Mulberry Planting
- Planting must be taken up soon after the onset of South-West monsoon to take full advantage of following showers.
- Cuttings or saplings can be used for planting.
- Two cuttings should be planted at each spot along the margin of ridges.
- If saplings are used, one is enough and is to be planted in a trench of 8" -9" depth.
Variety and preparation of Mulberry cuttings
- Now a days many High yielding varieties have been available such as V1, S-series, M5 etc., which give higher leaf yield of better quality.
- Cuttings must be prepared from fully grown upto 6-8 months old shoots.
- Each cutting must be 7" - 8" in length, half an inch in diameter with 4-5 healthy buds.
- Ends of the cuttings must have clean cuts without damaging stem and peel off bark.
Land Preparation for Mulberry
- Before the onset of monsoon, land should be ploughed deep ( 12" - 16") followed by 2 - 3 light ploughings to bring the soil to a fine tilth and leveled.
- Add 20 tonnes of farm yard manure (FYM) per hectare and mix it with soil.
Spacing
- Prepare ridges and furrows at the distance of three feet 2' x 2' or 3' x 3'or paired Row system.
Soil and Climate for Mulberry
- 22 - 30 degrees temperature, 1000-2000 mm rainfall and 65-80 percent humidity are optimum for luxuriant growth of mulberry.
- Deep, well drained, fertile soil of clayey loam to loamy texture is better suited for higher yield of quality mulberry leaf.
- If soils are acidic or alkaline they can be rectified by the application of lime or gypsum respectively.
- Red loamy soils are preferable for mulberry cultivation
Overview of Mulberry Cultivation
- Mulberry can be grown under different climatic and wide range of soil conditions.Higher yields of quality leaf which is a pre-requisite for the successful cocoon harvest is possible by adopting the following package of practices.
- Soil and climate
- Land preparation
- Spacing
- Variety and preparation of cuttings
- Planting
- Maintenance of garden
- Intercultural operations
- Manure and fertilizer schedule
- Leaf Harvest
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