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C. R. Krishna Murti and T. S. S. Dikshith
effective. Jute bags and polyethylene-lined jute bags are also used in rural areas
to store grains. However, it is now established that bulk storage is preferable
to bag storage.
In recent years, efforts have been made by different organizations in the
country to design good storage structures to save the food grains. The Indian
Grain Storage Institute at Hapur developed various designs for outdoor structures
to store many kinds of commodities; these are identical to elevator storage. These
structures have been constructed with facilities to load and unload the bulk grains,
to fumigate them periodically, and to keep them free from insects, moisture,
and rodents. The insects that attack the stored grains include a variety of species.
Some of the insects destroy all kinds of stored grains, and others damage broken
or milled food grains. The high temperature and humidity inside the storage
structure greatly facilitate the growth and movement of the stored-grain pests.
To a certain extent, the infestation of different insects increases with higher
moisture content above the 10% level. By controlling the moisture content and
the temperature of the stored grains, it is possible to minimize pest activity. The
most common insect pests that attack different food products are shown in Table
10.6 (Agarwal, 1979; Pingale, 1964).
Presently, different insecticides are used to control the insect pests and to
protect the food grains. Malathion spray, ethylene dibromide mixed with EDCT,
and phosphine are the most common.
Apart from insects and rodents, microorganisms also damage most of the
food grain in postharvest storage conditions. Climatic conditions in India are
very favorable for the growth and sustenance of microorganisms in the grain
storages. Microorganisms impart different effects on the food grains and lead to
loss of grains. The infected grain develops an odd color and a bad odor and
tastes different. The kernel discoloration, loss of nutritional value, and production
of mycotoxins and other toxins are examples of harmful effects to the user.
Proper drying, aeration, and control of humidity and temperature are a few
factors that would minimize the spoilage of grain by microorganisms (Agarwal,
1979).
DDT and BHC were tested with encouraging results against Sitophilus
oryzae, Tribolium castaneum, and Silvanus surinamensis. The toxicity of free
and sorbed vapor of BHC and DDT has also been tested. The question of
hazardous residue and contamination in food grains has also received the attention
of several investigators (Mookberjee, 1964).
Bioassay tests of insecticides have been made using Trogoderma granarium,
Latheticus oryzae, Oryzaephilus surinamensis. Laemophloeus minutus, Tribolium castaneum, Lasioderma serricorne, and Sitophilus oryzae. These studies
help as guiding factors for the choice of a suitable insecticide for the control of
insect pests.
The use of fumigants for the control of insect pests in storage is the most
C. R. Krishna Murti and T. S. S. Dikshith
effective. Jute bags and polyethylene-lined jute bags are also used in rural areas
to store grains. However, it is now established that bulk storage is preferable
to bag storage.
In recent years, efforts have been made by different organizations in the
country to design good storage structures to save the food grains. The Indian
Grain Storage Institute at Hapur developed various designs for outdoor structures
to store many kinds of commodities; these are identical to elevator storage. These
structures have been constructed with facilities to load and unload the bulk grains,
to fumigate them periodically, and to keep them free from insects, moisture,
and rodents. The insects that attack the stored grains include a variety of species.
Some of the insects destroy all kinds of stored grains, and others damage broken
or milled food grains. The high temperature and humidity inside the storage
structure greatly facilitate the growth and movement of the stored-grain pests.
To a certain extent, the infestation of different insects increases with higher
moisture content above the 10% level. By controlling the moisture content and
the temperature of the stored grains, it is possible to minimize pest activity. The
most common insect pests that attack different food products are shown in Table
10.6 (Agarwal, 1979; Pingale, 1964).
Presently, different insecticides are used to control the insect pests and to
protect the food grains. Malathion spray, ethylene dibromide mixed with EDCT,
and phosphine are the most common.
Apart from insects and rodents, microorganisms also damage most of the
food grain in postharvest storage conditions. Climatic conditions in India are
very favorable for the growth and sustenance of microorganisms in the grain
storages. Microorganisms impart different effects on the food grains and lead to
loss of grains. The infected grain develops an odd color and a bad odor and
tastes different. The kernel discoloration, loss of nutritional value, and production
of mycotoxins and other toxins are examples of harmful effects to the user.
Proper drying, aeration, and control of humidity and temperature are a few
factors that would minimize the spoilage of grain by microorganisms (Agarwal,
1979).
DDT and BHC were tested with encouraging results against Sitophilus
oryzae, Tribolium castaneum, and Silvanus surinamensis. The toxicity of free
and sorbed vapor of BHC and DDT has also been tested. The question of
hazardous residue and contamination in food grains has also received the attention
of several investigators (Mookberjee, 1964).
Bioassay tests of insecticides have been made using Trogoderma granarium,
Latheticus oryzae, Oryzaephilus surinamensis. Laemophloeus minutus, Tribolium castaneum, Lasioderma serricorne, and Sitophilus oryzae. These studies
help as guiding factors for the choice of a suitable insecticide for the control of
insect pests.
The use of fumigants for the control of insect pests in storage is the most