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| Scientific Storage of Grains |
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| Besides crop production good crop management involves storage of grains before distribution. During storage grains and seeds are subjected to spoilage by various agencies. |
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 Biotic - Insects, rodents, birds, fungi, mites, bacteria |
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 Abiotic - Moisture and temperature |
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| The loss due to spoilage has been assessed to be to the tune of 9.3% annually. Besides wastage, there is also degradation in quality, loss in weight, poor germinability, discolouration and finally poor marketability. Therefore, it is important to protect grains from loss during storage. |
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 Drying |
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| At the time of harvesting the moisture content in grains and seeds varies from 15-35%. Besides, grains have a tendency to absorb moisture from the atmosphere. If the moisture content is high, seeds are prone to be infested with pests and this in turn will decrease their quality. Hence moisture content in grains and seeds must be reduced to below 9% for their safe storage. To achieve this seeds have to be spread out and dried in the sun before drying in the shade. Mechanical hot air driers could also be used. |
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 Hygiene |
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| Granaries, godowns and stores should be well cleaned before stacking fresh grains. Any refuse, dirt, cobwebs and husk of the previous grain should be swept. The premises should be well maintained and any crack or hole in the wall, floor or ceiling should be sealed. Before reusing old gunny bags, they should be turned inside out, dusted thoroughly, exposed to sun and fumigated. If earthen pots are used, they should also be cleaned well and exposed to sun before storing fresh grains. |
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 Prophylactic treatment |
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| As a preventive measure godowns should be treated with insecticides and pesticides. Gunny bags should also be sprayed. Grains that have to be used for seed purpose must be mixed with fungicide and insecticide. |
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 Modern storage structures |
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| Research organizations have developed improved storage structures which have proved comparatively safe for the storage of grains. In these structures, temperature, moisture, oxygen and carbon-di-oxide can be adjusted to protect the grains. The structures are airtight, moisture impervious, thermally insulated and rodent proof. Changes in outside temperature do not effect the grains stored in these structures. Some of these storage structures are Pusa Bin, Pusa Cubicle, Pusa Kothar and Pant Kuthla. |
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 Pest control |
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| It is not safe to mix insecticides and pesticides with grains meant for human or animal consumption. If any of these are used they should be within safety norms. |
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| i) Chemical control |
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| Spraying of BHC wettable power, pyrethsum and malathion at 3 weeks interval can be done as a prophylactic treatment of the surface area of the store house. The dosage recommended is as follows. |
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| BHC WP (50%) 31/100m2 area in 1:25 dilution |
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| Pyrethsum (2.5 EC) 31/100 m2 area in 1:300 dilution |
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| Malathion (50 EC) 31/100m2 area in 1:300 dilution. |
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| Note: Many of these chemicals are contact poisons
and care should be taken while using them. Gloves and masks should be used
by the person spraying the chemical. |
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| ii) Fumigation |
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| Fumigants are chemicals that can exist in sufficient concentration to be lethal to pests. The following are well known fumigants. |
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| The recommended concentration is given alongside. |
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| (a) Aluminum phosphide tablets (black poison) 3 gms each, to be used at the rate of 2 tab/tonne grain or 160 tab/100 cub.m volume of grain. |
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| (b) Methyl bromide at 16 gm./cub.m. |
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| (c) Ethyl dichloride carbon tetrachloride (EDCT) 3:1 mixture at 30 ml/100 kg produce. |
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| Note: Masks and gloves should be used while handling
fumigants. |
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| iii) Plant products |
| Often a small quantity of vegetable oil or mineral oil is added to grains of legumes to protect them from insects. The treatment prevents laying of eggs, reduction in egg hatching and prevention of larval development. Some of the plant products used for this purpose are neem kernel powder, crushed pepper etc. |
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