Seed Production of Vegetable, Tuber and Spice Crops

Types of seed storage

1. Bulk (open) storage

• It is preferred over bag storage for the following reasons
• Large quantities of food grain can be stored
• No difficulty in loading and unloading of grain
• No need to purchase storage containers like gunnies
• Insect incidence is less than bag storage, even this can be eliminated by fumigation in situ
• Avoids waste from leaking bags
• Easy inspections- saves labour and time.



2. Bag storage

• Commodities are mostly stored in gunnies.
  
• Storage in bags requires considerable labour, but the minimum investment is enough on permanent structures and equipment.
  
• The storage in ags has the advantage of being short-term storage.
  
• Bag storage can be done under a roof alvanized iron sheets, a plastic covering where grain is intended for very early onward movement.
  
• Bags can be easily handled for marketing purpose.
  
• There is no sweating of bags as they are arranged in racks with proper interbag space, but, initial cost is high and they can easily pickup infestation and retain even after treatment.



Classification of packaging materials or containers used for bag storage
1. Moisture and vapour pervious containers

• These containers allow entry of water in the form of vapour and liquid.
  
• These are suited for short term storage.
  
• The seeds in these containers will attain seed equilibrium moisture with the surrounding atmosphere eg., cloth bags, gunny bags etc.
2. Moisture impervious but vapour pervious containers

• These allow entry of water in the form of vapour and not in liquid.
  
• The seeds in these containers can’t be carried over for long period in hot humid conditions.
  
• eg., polythene bags of < 300 gauge thickness and urea bags.
3. Moisture and vapour proof containers

• These containers will not allow entry of moisture in the form of liquid or vapour.
  
• These are used for long term storage even in hot humid conditions if the seeds are sealed at optimum moisture content eg., polythene bags of > 700 gauge thickness, aluminium foil pouches, rigid plastics etc.