1. Introduction Mushrooms are reproductive structures of edible fungi that belong to Ascomycotina, Basidiomycotina. These may be epigeal of hypogeal like any other fungus; the vegetative parts of the mushroom consist of thread like, thin mycelia which under suitable conditions from fruit bodies (sporocarps). All mushrooms are fungi but all fungi are not mushrooms. Mushroom occurs under various ecological conditions from desert to forest. They comprise a large heterogeneous group with different shapes, sizes, colour and the edibility of the 2000 known edible species, only 20 are commercially cultivated and 4-5 species produce o industrial scale throughout the 2 world. Some important mushrooms grown in India are listed below:Common name Scientific name

1. White button/Temperate mushroom Agaricus bisporus2. Oyster mushroom Pleurotus sajo-caju3. Paddy straw/Chinese/Tropical mushroom Volvariella volvacea4. Shiitake mushroom Lentinus edodes5. Milky mushroom Calocybe indica6. Maittake Gritola frondosa7. Enokittake Flamulina velutipe2. BRIEF HISTORY OF MUSHROOM CULTIVATION

Mushrooms have been used as a delicacy for more than two thousand years. During the middle Ages, the Greeks and the Romans considered mushroom as a special food and they were obtained only in autumn and spring. Because of mushroom, poisoning the wild forms or toadstool become objects of fear and distrust. Most poisoning cases were characterised by extreme pain and suffering before death. Cultivation of Agaricus was started in Europe early in the eighteenth century.Many years before the development of mushroom production in the United States and Europe, the Chinese had long been growing mushrooms. Auricularia auricula was first cultivated in China in A.D.600 while Flammulina veltipes was grown around A.D.800-900. Cultivation of other mushrooms such as Volvariella volvacea, Lentinus edodes and Tremella fuciformis was first recorded in China in the years 1000, 1700 and 1800, respectively. In, France the earliest attempts for cultivation were by using a method which utilized horse manure. The manure was prepared and the spores from the wild mushrooms were sown directly on the manure. Portions of the manure heap colonised by mycelium were also used to inoculate new horse manure. A few years later, some growers started to prepare composted horse manure beds inside caves and experimented with the use of pre-germinated spores or spawn to start a crop. A casing material made up of rotten leaf litter was later added to stimulate mushroom formation. By the end of the 19th century, a mushroom industry based on the growing of Agaricus Bisporus evolved in the western hemisphere, mainly in the United States and Western Europe.The development of the mushroom industry was stimulated in 1960 with the establishment of laboratories for research on mushroom growing not only in United States and Europe but also in Japan, Taiwan, and Korea, improved technologies on the use of mushroom worldwide. Mushrooms are now produced in some 18 countries around the world. In the United States, Mushroom growing started in the New York City in 1880. The industry has since then developed considerably, especially in Pennsylvania which produces over 44% of the total U.S. mushroom crop. Agaricus mushroom accounts for the largest percentage of the total world production, followed by Lentinula edodes. Important historical developments in India are as follows:

1908: Sir David Prain search edible mushroom

1938: experimental cultivation of paddy straw by DOA, Chennai.

1943: Details of cultivation of paddy straw mushroom by Thomas et al.

1961: First serious attempt on cultivation on cultivation of Agaricus Bisporus

(A scheme was started by HP Govt. And ICAR Solan)

1971: ICAR co-ordinated scheme started

1977: UNDP supported mushroom development project in Himachal Pradesh. Mr James Tunney got bulk pasteurization chambers constructed. Readymade compost and casing soil made available to the farmers of the Himachal Pradesh.At present white button mushroom contributes about 85% of the total mushrooms. Oyster mushrooms are becoming more popular in south India and Tamil Nadu alone is producing 3500 MT per annum. Because of poor and unpredictable yield, Paddy straw mushroom has not picked up very well.

3. MUSHROOM PRODUCTION IN INDIA

Today, India is exporting fruits and vegetables in limited quantities and earning foreign exchange for the country. Mushroom production is receiving top priority for export and domestic consumption in the country. Presently there is tremendous spurt in mushroom growing activity the country and big commercial units and small farmers are increasing, in numbers everyday. Now white button mushrooms are growing all over the country in environmentally controlled condition cropping house with tremendous success.

While seasonally by the small and marginal farmers in rural India with good results. Today mushroom are growing in Tarai region of U.P., H.P., and Haryana.Oyster mushroom is grown in all over the country with greater success and productivity and cultivation of these mushrooms is within the reach of the economically weaker section of society like smell farmers, rural women and unemployed youth.

Paddy straw mushroom commonly grown in humid weather and hot peninsular region of India is now popularly grown in villages and town in these areas with greater productivity. These mushrooms have a very strong aroma and good taste and its consumption is confined to areas where it is grown.White milky mushroom is good option for these regions where Button, Oyster and Paddy straw mushroom cannot grow in the month of April-July due to higher temperature in the hotter region.

At present 09% of this total production is Button and Oyster mushroom, milky and paddy straw mushrooms contributes only 10%. Productivity of button mushroom has also increased from 2-3kg/ m2 in 1965 to 18-20kg /m2.4. MUSHROOM VALUES

Food values:Mushroom contains 2o -35 % proteins on dry wet basis which is higher than vegetables, fruits and also good biological value. Mushroom is rich in lisone and tryptophan, the two essential amino acids that are deficient in cereals. The most nutritious mushrooms are almost equal in nutritional value to meats and milk.

Meditional Values:

There are more than 100 species of higher fungi that are commonly used in traditional medicine

i) Genedorma lucidun: It can reduce blood pressure, blood cholesterol and blood sugar level and inhibit platelet aggregation. Its cancer curing ability is attributed to various polysaccharides.

ii) Lentinus edodes: It cures bronchitis inflammation headache smallpox etc.

iii) Grifole frondosa: It is been frequently used for improving spleen

and stomach ailment.

5. PREPARITION OF MUSHROOM SPAWN

The propagating material used by the mushroom growers for planting is called mushroom for spawn production can be grown on boiled and sterilized cereal grains eg. Wheat, bajra etc. Grains are prefer as substrate for mushroom spawn because grains give a large number of inoculation sites, each with high inoculums potential derive from the nutrient base. Usually, cereal grains are colonized with mushroom mycelium and they are used for seeding in the composed.

REQUIREMENTSPure culture of mushroom cereal grains (wheat, bajra etc.)

Calcium carbonate (chalk, caco3)

Calcium Sulphate (Gypsum, caso4)

Saline bottles (500 ml)/ polypropylene bags

Non absorbent cotton

PROCEDURE

Well clean and healthy cereal grains are boiled for 30 minutes or until they become soft;

Excess water is drained after boiling and grains are cooled in wooden/ plastic tray.

These cooled grains are mixed with 2% calcium carbonate and 2% calcium sulphate on dry wet basis of grains to avoid clumping of grains.

Boiled cereals grains are tiled (300 gm/ bottle) in clean 500ml saline bottle or polypropylene bags and plugged with non absorbent cotton plugs.

These cereal grains filled bottles/ bags are sterilized in autoclave at 15 lb pressure 21c. For 1hrs. And then allowed to cool at room temperature.

These sterilized and cooled grain filled bottles/ bags are aseptically inoculated with mycelia bits which of 7-10 Days old mushroom m culture. These inoculated bottles/ bags are incubated at 20c. In BOD or 2 weeks incubated.

These bottles/ bags are second at 4 days interval to allow proper spread of mycelium between the grains and these bottles/ bags are than completely colonized by mushroom mycelium in 2 weeks.OBSREVATIONS:

Observe the iniculative bottles/ bags during incubation at regular interval for the apperials of white mycelium on the grains as well as for the appearance of contaminants (bluish, greenish, blackish etc.growth)

PRECAUTIONS

Cleaned and healthy cereals grains should be selected for spawn making. Never boil the grains for longer period.

Mycelia bits of 10 days old culture should be preferred for inoculation.

Always keep a check for microbial contamination of the spawn during incubation.

6. CULTIVATION OF OYSTER MUSHROOM (Plurotus species)Oyster mushroom has become a well organized part of our country and world mushroom industries. The desirable attributes like fast mycelia growth, high ability for saprophytic colonization, very simple and cheap techniques, higher yield and cheap post harvest storage and above all the wide choices of Plutorus sp. Available for cultivation under different climatic conditions has contributed to its popularity.REQUIREMENTS:Mushroom spawns

Agricultural residues

Polythene bags

Sterilization equipments

Plastic drums

Wooden tray

PREPAATION OF SUBSTRATE:Oyster mushroom can be grown on various agricultural waste materials. However, Wheat straw and Paddy straw are best substrate for cultivation of Oyster musroom and they give higher yield. For preparation of substrate, cereal straw is soaked in water for 18-20 hrs and then drain off the excess water. Various methods of substrate sterilization have been developed for Oyster Mushroom cultivation. Steam Pasteurization by autoclave, hot water treatment, and chemical sterilization is effective methods and they are adopted by mushroom growers on large scale.

VARIOS METHODS FOR SUBSTRATE FOR OYSTER CULTIVATION AUTOCLAVING:

The moist substrate is steamed under pressure inside the autoclave for 20mins at10lb. After sterilization substrate are taken out of the autoclave and allowed to cool down at room temperature.

CHEMICAL STERELIZATION: The pre-soaked substrate is again emerged in 0.05% water solution of bavistin for 12hrs and the excess solution is drained off from the substrate. Another chemical sterilization is then moistened substrate fumigated with formalin for 12 hrs in airtight chamber. This Substrate is exposed to air after fumigation for 1 hr t get escape from the odour of formalin. SOLARIZATION:

The moistened straw are spread on cemented floor in thin layer and covered with clean polythene sheet and treated to sunlight from 10A.M. to 4P.M

SPAWNING: The mixing of spawn in the sterilized substrate is called spawning. The amount of spawn is 3-3.5kg/quintal substrate. The spawning is usually done by mixing and layer methods .The cylindrical polythene bags can be used for spawning. The spawned substrate is filled in polythene bags and moth of each bag is bine with rubber band threads and 8-10 small holes are made8-10 cm apart from each other.

7. WHITE BUTTON MUSHROOM

The white button mushroom is very popular throughout the world and is the most important in the commercial scale. This mushroom is extensively cultivated about 65% of the total work production of the mushroom. At present India is roughly producing about 50,000 tonnes of these mushrooms. It can be successfully cultivated in place where the environmental condition is favourable. The optimum temperature for mycelia growth is 20-25c and tat for fruit body formation and also needs a high percentage of relative humidity of 80-90%. Cultivation of white button mushroom requires technical skills.

IMPORTANT FORMULATIONS A. COMPOSTFORMULATIONS USED IN INDIA

i.N.C.M.R.T. (National Centre for mushroom research and training) at Sloan a. Wheat straw300kg

Wheat bran15kg

Chicken manure123kg

Urea5.5kg

Gypsum20kg

BHC (10%)125kg

b. Wheat and Paddy straw300kgCalcium ammonium nitrate9kg

Urea4kg

Wheat bran 15kg

Gypsum20kg

BHC (10%)125kgii. I.A.R.I. (Indian Agricultural Research Institute), New Delhi

Horse yard manure1000kg

Wheat straw500kg

Urea30-40kg

Gypsum30kg

iii. I.I.H.R. (Indian Institute Horticulture Research), Bangalorea. Paddy straw150kg

Maize stalks150kg

Ammonium Sulphate9kg

Super phosphate9kg

Urea4kg

Rice Barn50kg

Cotton seed meal5kg

Gypsum12kg

Calcium Carbonate10kg

b.Wheat straw or300kg

Paddy straw400kg

CAN9kg

Super phosphate9kg

Urea4kg

Wheat Barn30kg

Gypsum12kg

Calcium 10kg

METHOD OF COMPOSTING:There are two methods of composting in India.

LONG METHOD OF COMPOSTING (LCM)

Preparation of compost by LCM is a primitive method. It takes more time, gives low yield and invites more disease and pest. In India this method is followed by many small farmers. Yield obtained using such compost range between 8 and 12 kg /100kg of compost.

METHOD:The first step in the compost preparation is to clean composting yard properly and to spray 2% Formalin 24hr. in advanced of operation. On the following day wheat straw and the paddy straw and any other recommended base material is spread over the straw by pipe and frequently turned by forks till it absorbs sufficient moisture. Wetting of the straw may continue up to 24hrs. Care is taken that every portion of the straw absorbs required quantity of water so that there is no further requirement of water till the composting process is over. This wetted straw is collected and made into a smaller heap. Similarly all other ingredients except gypsum and BHC are mixed, moistened with water and the heap is made which is covered with moist gunny bags. When wetting of straw and other ingredients is over, these are kept as such for 24hrs and this day is called day 1. The day when these two (wheat straw and other ingredients) are mixed and made into a heap is known as 0 day.Day 0:

The two ingredients (base materials and fertilizers) which were kept after wetting are mixed. Mixing can be done thoroughly with the forks. The Mould is completely filled up to the required height, the side board are removed lengthwise and the material is filled in the space by the means of forks described earlier. Temperature above75c is not desirable.Day 1-5:

It should start rising within 24-48 hrs after stacking and may reach up to 65-70c in the central portion. Temperature in the compost stock is directly related to the amount of nitrogen used in the mixture. If moisture of the compost mixture is less, then more water is added. Watering should be stopped as soon as leaching starts from the bottom of the pile.Day 6 (1st turning)Turning is done to ensure that every portion of the piles gets equal amount of aeration and water. To give turning remove about a ft. of compost from the top and the sides of the pile, shake it thoroughly so that excess ammonia is released and it is exposed to air properly, keep this portion in one side of the pile, shake properly and keep them separately. Make a new pile with the help of the mould described earlier keeping central portion at the bottom. Top and sides should be placed at the centre while the bottom part comes on the top sides.Day 10(2nd turning):

Break open the pile and turned as described earlier.

Day 13(3rd turning):

Turning is done and required quantity of gypsum is added.

Day 16(4th turning):

Day 19(5th turning):

Day 22(6th turning):

Day 25(7th turning):

Required quantity of BHC is added during turning.

Day 28(Filling day):

Break open the pile and check for the ammonia smell if no ammonia persists and a sweet smell is coming out, compost is filled in the trays or bags after spawning. If slight smell of ammonia is detected, then compost is kept as such opened for 1 day. Excess of ammonia will disappear and the compost will be ready for spawning ammonia should not be more than 8-10ppm at spawning.The method described above takes about 28-30 days to accomplish this composting.

ATTRIBUTES OF GOOD COMPOST:Good compost should be dark brown in colour, not greasy or sticky, have distinct sweet inoffensive smell, free from ammonia smell, with 68-72% moisture and 7.2-7.8 pH. There should not be the visible growth of other undesirable organism except for the fire fangs (Actinomycetes) and it should be free from insects and nematodes. For the control of undesirable organisms, addition of formalin (0.5%) and bavistin (0.015%) in the compost 24-48 hrs prior to spawning is effective.SPAWNING:

Spawning is the mixing of spawn in the prepared compost for sowing. Completely colonised and fresh spawn is 2-2.5kg/quintal compost. The spawned compost @ 5kg is filled in one polythene bag. The upper surface of the compost is covered with the bags paper sheets within the polythene bag. These spawned bags are placed in growing chamber where temperature ranged between 20-25c.

CASING:

After spawn run, the mycelium becomes ready to enter the reproductive phase to produce the frit bodies (mushroom). However it will not produce fruit bodies unless the compost surface is covered. The process of applying casing layer growth and development fruit bodies and maintain humidity and temperature in the growing chamber.

After completion of spawn run, the newspaper sheet is removed and surface of compost is covered (3-4cm thick) by casing soil. The casing farm yard manure is sterilized by autoclaving of formalin solution before casing. Mushroom beds are sprayed regularly with water to keep the casing layer adequately moist.COMMON DISEASE OF MHITE BUTTON MUSHROOM Bacterial blotchCommon name: Brown blotch, Bacterial spot, Mushroom blotch.

Symptoms: This is the most serious bacterial disease of white button mushroom. The pathogen induces lesions on the surface of fruit bodies that are pale yellow initially but become golden yellow or chocolate brown later.

Causal organism: --------------

Management:

1. Manipulation of relative humidity, temperature and air velocity are significant preventive measures are managing the diseases.

2. Sterilization of casing soil by steam has been effective in eliminating the bacterial pathogens.

Brown plaster mould

Symptom:

Brown plaster mould is a very worst competitor and causes around 90% yield losses in white button mushroom. Symptom appears as white fungal growth on the expose surface of compost and casing soil. Mushroom mycelium does not occur completely colonized by brown plaster mould and sometimes entire crops failure.

Causal organism: Papulospora byssinaManagement:

1. Peak heating should be of sufficient duration at proper temperature and sufficient supply of fresh air during pasteurization.

2. Strict hygienic cultivation methods should be followed.

Harvesting:

Pinheads generally appear during 15 days water casing and they become ready for harvesting within another one week. Mushroom is picked by gently twisting off the button without casing disturbances. Small pits are formed after harvesting and these pits are immediately re-ceased with casing soil for development of nest fruit bodies. The moisture in the casing soil is maintained by regular spraying of water.Water casing and they become ready for harvesting within another one week. Mushroom is picked by gently twisting off the button without casing disturbances. Small pits are formed after harvesting and these pits are immediately re-ceased with casing soil for development of nest fruit bodies. The moisture in the casing soil is maintained by regular spraying of water.

YIELD:The yield of the white button mushroom depends on the compost ingredients, supplements used in the compost, casing materials, temperature and relative humidity 15-20 kg fresh button can be raised from 1 quintal compost.8. PRESERVATION AND PROCESSING OF MUSHROOM:Mushroom are readily perishable commodities and start deteriorating after harvest. They develope a brown discoloration on the surface due to the enzymatic action of phenol oxidises and becomes soft at high temperature. The rate of respiration activity of the harvested mushroom is high, compare to other horticultural crops resulting in a shorter shelf life. Development of appropriate preservation and processing technology in order to extend their marketability and availability to the consumers in fresh as well as processed form is of great significance. Short-term preservation methods like pre-packing cooled with low temperature storage, irradiation and steeping preservation helps to prolong self life for 1-3 weeks.Long time Preservation methods such as canning, drying, pedalling dehydration, etc. can make the availability throughout the year at reasonable cost.

1. Introduction

Sericulture or silk farming is a branch of agriculture, the raising of silkworm for their cocoons, which are the raw materials used in the manufacture of silk. Sericulture is the rearing of silkworm for the rearing of silk. Although there are several commercial species of silkworm, Bombyx mori is the most widely used and intensively studied. According to Confucian text, the discovery of silk production by B.mori dates to about 2700 BC, although archaeological records point to silk cultivation as early as the Yangsha period (5000-10000 BC). About the first half of the first century AD it has reached ancient Khotan, and by AD 140 the practice has been started in India. Later it was introduced to Europe, the Mediterranean and the other Asiatic countries. Sericulture has become one of the most important cottage industries in a number of countries like China, Japan, India, Korea, Brazil, Russia, Italy and France. Today China and India are two main producers, together manufacturing more than 60% of the world production each year.KINDS OF SERICULTURE IN INDIA AND SIKKIMIndian sericulture contributes four types of silk viz, Mulberry, Muga, Eri and Tasar. Mulberry accounts for 805 of the total production in the country. In the context of the rural development, sericulture serves the social objectives like:

1. It provides off-farm employment.

2. It prevents immigration of poor people.

2. TYPES OF SILKWORMS:There are 4 major types of silk having commercial importance obtained from different species. These are:

1. Mulberry silkworm

2. Muga silkworm

3. Eri silkworm

4. Tasar silkworm- (a)Tropical tasar

(b)Temperate tasar

Mulberry silk:

Mulberry silk comes from the silkworm Bombyx mori which solely feeds on the leaves of the mulberry plants. These silkworms are completely domesticated and reared indoors. The bulk of the commercial silk produced in the world comes from this variety.

Muga silk:

Antheraea assamensis produce golden yellow silk. Production of this variety is abundantly on the Brahmaputra valley of Assam in India, It is semi domesticated. The worms are raised on Machilus hombycina and Litsaea polyantha trees. At the end of larval period they crawl down in the trees in search of the suitable place for the construction of the cocoons. The cocoon has a very weak peduncle and is golden yellow. The cocoons are boiled in soap and soda solution and are reeled.

Eri silk:

This silk is produced by Philosamia ricini. The primary food plant of this silkworm is caster. This silkworm is Multivoltine and is reared indoor. The eggs are white and hatched in 10 days. The worms moult 4 times during its larval period of 30-32 days. The cocoons are usually white. The cocoon of the eri silkworm cannot be reeled, as they are made up of uneven fibre.

Tasar silk:

Tasar silk extracted from 3 species of Antharea are used in India, they are Antherae pernivi, Antheraea mylitta and Antheraea royeli. Tasar silkworms are reared wild in nature and usually brown in colour. It is less lustrous than Mulberry silk, but has its own feel and appeal

Oak tasar: it is a finer variety of tasar. It is produced in high altitude region. 3. LIFE CYCLE OF SILKWORM

Silk is a valuable natural conjugated protein. It is biological secretion of a moth named Bombyx mori. The silkworm metamorphoses into a beautiful moth from its initial stage of an egg. The entire lifecycle of silkworm completed from egg to egg stage following larva, pupae and moth stage.

LARVAL STAGE:

The caterpillar that emerges from the egg is only 1/8th of an inch long. Extremely hairy young silkworms can feed on the tender mulberry leaves. The larval stage lasts for about 27 days and the silkworm goes through 5 growth stages called instars. During first moulting, the silkworm sheds all their hair and gains a smooth skin.

PUPAL STAGE:

After the Chrysalis stage in the larval stage, the caterpillar will spin a cocoon of silk thread around itself. The cocoon is about the size of the nut ball.

MOTH:

The moth has creamy white wings with brown patterns across the front. Once the adult moth comes out of the cocoon, its only purpose is to find a member of the opposite sex and mate. Males are very active; they flap their wing rapidly to attract the females. Within 24hrs of mating, the male moth dies, while the female lays abundant eggs, after which she dies. There on, a new silkworm lifecycle begins.

SILKWORM REARING:

Silkworm rearing is considered to be an agro based cottage industry since it involves mulberry cultivation. Silkworm is reared for the production of cocoons which is the raw materials for the silk production. The farmers rear silkworm and produce cocoons. By marketing the cocoons the farmers earn money. It is ideally suited for the rural areas of sericulture state. Silkworms are reared is well ventilated shed following shoot rearing method.

4. SILKWORM MANAGEMENT

Silkworm rearing:

Mulberry silkworm has been made domesticated since last many years and the sole food for the growth of the mulberry silkworm is mulberry leaves, while wild silkworms feed different food plants.

Climatic requirements:

Climatic factors like temperature, humidity plays an important role in silkworm rearing and in the development of the larvae as the temperature increases the development of the larvae activities.

Temperature and humidity requirement:

Sl.no.STAGETEMP. (C)HUMIDITY (%)

11st instar26-2885-90

22nd instar26-2885-90

33rd instar25-2680-85

44th instar24-2570-75

55th instar23-2470

Requirement of leaf differ from race to race and also varies with season. During summer the quantities of leaf requirements will be little higher since, drying of feeding will be faster hence additional feeding may be required.

Rearing equipments required

1. Mesh

2. Sprayer

3. Mats

4. Chopping board

5. Chopping knife

6. Chop sticks

7. Feathers

8. Foam pads

9. Rearing trays

10. Thermometer

11. Plastic buckets/ mugs

12. Rearing stands

13. Feeding stands

14. Mountages

15. Hygrometer

16. Bed cleaning net

SILKWORM FEEDINGThe nutrient value and number of feeds in each instars plays a major role in cocoon formation. 3-4 feeds are given to silkworms a day. During moulting period no feeding should be given. Feeding tender leaves to young age worms is essential. As the larval growth increases or advances the mature leaves can be fed.

The larva development will be maximum during the 5th instar and 4th moult. Generally the moulting period delays due to fluctuation in climatic conditions.

Rearing rooms:

Rearing room must be constructed with east/west direction, with the thatched roofing, mud walls or any roofing should not reflect the heat on the body of silkworm. Keep good number of windows, proper ventilation and light facilities. The raring have a good length and breadth.

Leaf quality:

Leaf quality plays an important role in the production of quality cocoons. The young age worms are fed with tender, succulent leaves because these leaves contain high moisture and protein content, less fibre, starch. Protein content required or needed by the worms for their good growth and development. Hence, top tender leaves of mulberry plants are to feed the young age silkworms.

Leaf requirement:

Silkworms attains nearly 10000 times of weight starting from thatching to spinning stage, therefore, feeding good quality leaf plays an important in the development of silkworm.LEAF REQUIREMENT FOR WORMS:

Temperature and humidity requirement:

Sl.no.STAGEQuantity of mulberry leaf required Approx(kg)

11st instar2-4

22nd instar4-8

33rd instar30-40

44th instar80-90

55th instar600-650

Maximum leaf is consumed during 5th instar only, because during this stage the maximum growth of silk gland can be noticed.

FEEDING SCHEDULE:

Sl.no.1st feeding 2nd feeding3rd feeding 4th feeding 5th feeding

16A.M.-6:30P.M.11A.M.-11:30P.M.3A.M.-3:30P.M.7A.M.-7:30P.M.

27A.M.-7:30P.M.11-11:30A.M.2A.M.-2:30P.M.5A.M.-5:30P.M.

36A.M.-6:30P.M.10-10:30A.M.2A.M.-2:30P.M.6A.M.-6:30P.M.10A.M.-10:30P.M.

BED CLEANING:

Silkworm after moulting leaves the excreta. Dried leaves, silkworm excreta, dead worms, diseased larvae all will increase the humidity and temperature in the bed. If proper bed cleaning is not done in time it leads to various complications such as ill health of larvae, disinterest of the larvae to feed due to unhygienic conditions and ultimately worms becomes weak.

Duding 1st instar bed cleaning should be done once during pre-moulting, during 2nd instar twice, and one after moult and before next moult. During 3rd instar thrice i.e. after moult and before next moult and once in the middle. During 4th and 5th stage once in a day in case of self rearing. However, in case of floor rearing or shoot rearing once in each instar.

MOUNTING:

Transferring of matured silkworm on to mountage on cocoon frame is called Mountage. It is a skilled and important operation. This is the last stage of rearing operation. At this stage silkworm becomes matured completely and ready to spin into cocoon. This silkworm after 5 days of 4th moult becomes yellowish and translucent, stops feeding the leaves and crawl on the feeding trays. Further they ooze out the liquid like substances out of the mouth from the spinneret. This movement clearly indicates to transfer the mature larvae into the mountages. Mountage should be kept in inclined position so that, excreta of the worms fall in the ground. In a standard mountage of 90x60cm size around 250-300 worms can be conveniently mountage.

During mounting care should be taken to use the right type of chandrike in convenient size and shape. There are different types of chandrike that are used for the purpose of mounting, they are:

1. Plasting mountage

2. Bamboo made chandrikes

3. Straw mountage

4. Bottle brush

5. SIKWORM EGG PRODUCTIONSuccess of sericulture depends on the quality silkworm eggs. Therefore management of seed production, interalia transportation, incubation and prevention from disease play important role on overall return. To produce quality seeds, it is very important to adopt scientific methods of cocoon production right from seed crop rearing to egg incubation.

DISINFECTION:The grainage rooms along with its appliances should be thoroughly disinfected prior to commencement of operation and kept ready to receive seed cocoons. The rooms and appliances are to be washed with 5% bleaching powder solution and the appliances are to be properly disinfected with a mixture of 2% formalin, 0.5% to 1% lime and 0.05% detergent solution.

6. TRANSPORTATION OF SEED COCOONS:Cocoons are loosely packed either in perforated plastic crates or bamboo baskets and transported to respective disinfection during cooler hours of the day.PUPAL EXAMINATION:Before selection of seed cocoons, it is very important to know the disease freeness of a lot, melt, flimsy and god cocoons are also to be separated. Cut portion is taken out and subjected to microscopic examination. In case there is incident of pebrin, the lot has to be rejected.

7. PRESERVATION AND PROTECTION OF COCOONS:Immediately after the receipt of seed cocoons, they are to be sprayed o n the tray in a single layer to facilitate good aeration. Sorting of good cocoons to be taken out and rejected. There should be Dross ventilation in the preservation room, 25+1 degree Celsius, 75+5 % relative humidity, 2hr light and 12hrs dark condition is to be maintained in the cocoon preservation room.

EARLY ECLOSION OF MOTHSThis helps in the disease freeness of the batch and helps in the minimizing the loss of the grainage. For early emergence of moth, 50-60 cocoons are taken from the individual lots and placed into an artificial eclosion box. The temperature in the box is adjusted to 32-33c with the help of thermostat. This accelerates the development of pupa and moth emerges early. The early emerged female moth of the respective lots are taken and subjected for microscopic examination to know the disease freeness of lots.

8. PROSPECTS OF THE STRENGTH OF SILK INDUSTRY1. Availability of different kinds of food plants abundantly reporting in different ecozones of Sikkim pertaining to mulberry. Oak, Tasar, Eri and Muga plantation in temperate to tropical areas.

2. Traditional inheritage of cultural wealth of silkworm rearing is practicing since ages.

3. Mulberry silkworm rearing quite profusely and richly conducted by silkworm rears and owing to temperate climatic profile.

4. Government of Sikkim has a promising infrastructure including many silkworm farms, Sericulture training schools, cocoon market, cold storage and other essentially required administrative, technical and ancillary assets governed under the independent directorate of Government of Sikkim.

5. Presence of rich wealth of sericigenous insects and suitable rich wealth of food plantation with a promising potential of employment to the rural population.

6. Availability of fellow land, desert land, Gram panchayat land other spare land, free to used for cultivation of food plants at different stages.

7. Recently, Muga and Eri silkworm culture added an advantage to silk activity and silk industry apart from Mulberry and Oak Tasar culture in practice since last many years.

8. Sericulture strengthening the rural population by providing employment at their door and check the migration from villages to town.

9. Sericulture is an eco-friendly avocation and does not create pollution but on contrary it assists the maintenance of ecosystem of the environment.9. PROBLEMS/ WEAKNESS OF SERICULTURE1. Lack of suitable silkworm seed in adequate amount required during different specifically to the merit of germplasm and commercial seed.

2. Lack of proper disinfection and maintenance of hygiene.

3. Lack of proper infrastructure of silkworm drainage especially of Muga and Eri silkworm seed.

4. Lack of addition of value added products of silk chadars, silk ties silk wall hangings.

5. Lack on emphasis on post reeling sectors almost in all sectors of silk.

6. Lack f trained silk professionals at field level.

7. Lack of dissemination of latest technical know-how and technology at gross root level.

8. Lack of paucity of funds and gap in implementations of silk schemes at agrarian and industrial level by scientist, technocrats, administrator/planners and executers.

10. SILKWORM DISEASE AND PEST MANAGEMENT

Mulberry silkworms are threatened by pebrine (H. Transovarian transmission of microsporidian, Nosema bombysis and strains of Nosema sp.), Grasserie (a viral disease caused by nuclear polyhedral virus), muscardie (fungal disease caused by Beauvaria bassiana) and aspergillosis (caused by Aspergillus flavus). Use of disinfectants like Vijetha and vijeta supplement, developed by the CSR&TI, Mysore, and other disinfectants like suraksha, sanjivani, Resharn jyothi developed by other research institute have been found effective, which besides preventing all silkworm disease also improve silkworm rearing performances and increase in cocoon by 12-15 kg/Dfls. had been recorded in the field, due to the application of the vijetha. For prevention and control of aspergillosi disease, Dithane M-45 in kaoline or Captan in slaked lime on silkworm body had also been found effective.

Uzifly ( Exorista bombosis ) is a serious endo-larval parasitoid of silkworm, Bombyx mori which is estimated to caused 10-20% losses, Integrated Pest Management (IPM)developed against Uzi fly, comprising biological agents ( Nesolynx thymus, an ecto-pupal parasitoid )along with physical (rearing in nylon-nets ) and chemical control methods such as uzitrap and spray of uzicide.

11. TECHNOLOGY FOR PREVENTION/ CONTROL OF DISEASE OF SILKWORM IN REARING HOUSE AND APPLIANCES1. CLEANING:

Immediately after the disposal of cocoons, collect at one place inside the rearing house, all diseased and dead larvae, pupae floss over mulberry, bed refuse, silkworm faces, dust dirt etc. and disinfect by sprinkling 5% bleaching powder solution and dispose off by burying at 2ft depth or burning.

2. DISINFECTION:

Measure the length and the breadth of the rearing house including the leaf preservation room, mounting room etc. and calculate the floor area for disinfection. The disinfectant required for disinfection of rearing house is 21ft/sq.mt. floor area. Disinfect the rearing house using 2% bleaching powder in 0.3% slaked lime, 2.5% chlorine dioxide in 0.5% or 2% formalin +0.05% detergent solution.

Spray using powerful jet sprayer, the required quantity of disinfectant ( 2.0lit/m2 floor area of rearing house 255 of disinfectant solution for appliances + 10% for outside of rearing house.) uniformly to drench all part of rearing house inside appliance out of rearing house and sundry for 10-12hrs.

Rearing tray are the main source of infection agent and most difficult and expensive to achieve disinfection. To avoid this, changing over the rearing silkworm on shoot is advantageous. This method does not require additional disinfectant for appliance as only the rack and nylons are used.

3. DISINFECTION PRIOR TO BRUSHING

5 days before brushing: The rearing house and appliances are cleaned, washed in water if tray and other appliance used conduct additional disinfection by dipping them in disinfectant and spraying disinfectant.

4days: sundry the appliance if the prevalence of viral disease (Grasserie and Flacherie ) were high during the previous crop, spray 0.3% slaked lime in water (3g/lit) to the rearing house and appliance @2lit/cm floor area additional requirement. Sundry the appliances after 12hrs of spray.

3days: conduct second disinfection of rearing house and appliances. Shift all the disinfected appliances into the disinfected rearing house and arrange in the room. Disinfect the rearing house and appliance by spraying 2% bleaching powder in 0.3% slaked lime solution or 2.5% sanitech in 0.5% in 0.5% slaked lime or 0.2% formalin+0.05% detergent solution. The second disinfection may follow the first if the gap is not too much.

2 days: Dust 5% bleaching powder in slaked lime powder in slaked lime powder @200gm/sq.mt at the entrance of the rearing house and the passage to it. Sprinkle water @ 1lit/sq.mt floor area. Prevent contamination of rearing house and appliances. 1 day: Arrange appliances for chawki rearing and mounting hall closed (and only 1 day before the larvae are to be shifted).

12. STRTIGIESSeveral strategies and scheme assistance proposed to provide the farmers and silk reeling entrepreneur involved in sericulture industry for the following basic amenities required for silkworm rearing and reeling.

For planting high yielding varieties.

Provisions of training to farmers in silkworm rearing for installing drip irrigation in mulberry garden.

For the construction of separate silkworm rearing house.

For the procurement of improved silkworm rearing equipments.

For the establishment of chawki rearing centres.

For the establishment of silk twisting units.

For the establishment of loom through jacquard.

For the establishment of silk reeling units in different levels.

13. THREATS OF SILK INDUSTRY

Intrusion of artificial, low cost, synthetic silk fibbers from other countries like China.

Rapid de-forestation, industrialization and deterioration of bio-resources in nature are a vulnerable threat.

Blending of undesirable silk fibres with polyesters/terralyn/shiffon and other synthetic fibre crushing the genuine silk market in regional, national, and global prospects.

Switching off traditionally wool/cotton weavers to silk industry is also not a healthy sign for rural employment through cotton industries.

Fire in forest and snowfall on high altitude plantation does not favour the silk industry.

Lack of heavierness, gender sensitization and liking parameter of male and female sexes of different age groups without an extensive survey and study also is under quest of threat.

14. CONCLUSIONAlthough sericulture has a traditional base in the country it is only after the efforts of different institution of the Central Silk Board that has brought change in the silk production of our country. Lots of improvement has been brought by the Central Silk Board like improving the feeding, rearing and improvement in the quality of international grade. Now our country is ready for a big leap to reach the top position among other silk producing countries. And the sericulture industry gave great opportunity to get employment to the future generation.