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.