Diseases and Management of Crops under Protected Cultivation

(Diseases and Management of Crops under Protected Cultivation)
tissue culture. Spores are collected in form of spore print by which multispore and single spore
isolation is done.Spore culture technique is generally useful onlyin breeding programmes and
genetic improvements of mushroom species. Some single-spore isolates made from
homothallic mushrooms, e.g. Volvariellavolvacea (primary homothallism) or Agaricus bisporus
(secondary homothallism) can be directly used as fruiting culture. However, if single-spore
isolates, obtained from heterothallic mushrooms, e.g. Lentinulaedodes, Pleurotus sajor-cajuand
Ganodermalucidum, are not fertile. They have to be mated with a compatible single-spore
isolate to produce dikaryon/fruiting culture which later on used in spawn making. Readymade
pure fruiting culture can also be obtained from any mushroom laboratory.The tissue culture is a
very simple technique and preservegenetic purity of valuable cultures. In this methoda piece of
healthy tissues is taken from immature mushroom fruit and placed centrally on the surface of
the medium with a sterilised needle for vegetative growth. About ten days later the myceliumwill
grow rapidly and cover the surface of the agar medium. Fully colonized test tubes can be stored
at low temperature for further use.
c. Spawn Preparation: Technique of spawn making comprises high cost equipments with
scientific knowledge and sound skill. Spawn itself explains as a master/mother spawn for first
generation from whicha second generation commercial spawn is prepared to sale. About
10kilograms of boiledwheat grains are mixed with 120 g gypsum (CaSO4. 2H 2 O) and 30g
calcium carbonate (CaCO 3 ). The gypsum prevents the grains from sticking together and
calcium carbonate is necessary to correct the pH. The prepared grains are filled into half-litre
milk / glucose bottles at the rate of 150-200 g per bottle (by three-fourth capacity) and
autoclaved at 20-22 lb. psi (126 o C) for 1 ½ to 2 hours. Sterilized bottles are shaken to avoid
clumpformation,while hot and allowed to cool down overnight. Next day, bottles are inoculated
with bits of fruiting culture and then incubated at 21±2 o C. Periodic shaking of bottles is done for
proper distribution and colonization of mushroom mycelium on to the wheat grains. Mycelium
completely permeates the grains within 2-3 weeks. The master spawn becomes ready for
further multiplication of second generation spawn. About15-25 spawned grains of master spawn
are transferred in thermostable polypropylene bags that contained 300-500g sterilized wheat
grains. Rest method of commercial spawn is same as master spawn.
d. Construction of crop room/huts: Mushroom being an indoor crop does not require arable
land except to construct crop rooms. In India mushroom production is done at seasonal and
high-tech industry level. In seasonal cultivation pukka ordinary rooms are required. These
rooms are generally made by brick walls and do not require insulation. Cropping room for
seasonal growing can also be made with thatched roof and false polythene ceiling. In these
rooms and hutsmushrooms are raised on beds made by bamboos sticks and sarkanda stems.
These seasonal growing rooms are varied in the volume. About 10x8x10 ft sized room or
thatchis enough to accommodate 4-6 quintal compost prepared from long method of
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