Seed Production of Vegetable, Tuber and Spice Crops (2+1)

Methods of sampling

a. Hand sampling

• This is followed for sampling the non free flowing seeds or chaffy and fuzzy seeds such as cotton, tomato, grass seeds etc.,
  
• In this method it is very difficult to take samples from the deeper layers or bag.
  
• To over come this, bags are emptied completely or partly and then seed samples are taken.
  
• While removing the samples from the containers, care should be taken to close the fingers tightly so that no seeds escape.
b. Sampling with triers

• By using appropriate triers, samples can be taken from bags or from bulk.
1. Bin samplers

• Used for drawing samples from the lots stored in the bins.
2. Nobbe trier

• The name was given after Fredrick Nobbe father of seed testing.
  
• This trier is made in different dimensions to suit various kinds of seeds.
  
• It has a pointed tube long enough to reach the centre of the bag with an oval slot near the pointed end.
  
• The length is very small.
  
• This is suitable for sampling seeds in bag not in bulk.





3. Sleeve type triers or stick triers

• It is the most commonly used trier for sampling: There are two types viz.,
1. with compartments 2. Without compartments.
• It consists of a hollow brass tube inside with a closely fitting outer sleeve or jacket which has a solid pointed end. Both the inner tube as well as the outer tube has been provided with openings or slots on their walls. When the inner tube is turned, the slots in the tube and the sleeve are in line. The inner tube may or may not have partitions.
• This trier may be used horizontally or vertically. This is diagonally inserted at an angle of 300 in the closed position till it reaches the centre of the bag. Then the slots are opened by giving a half turn in clockwise direction and gently agitated with inward push and jerk, so that the seeds will fill each compartment through the openings from different layers of the bag, then it is again closed and with drawn and emptied in a plastic bucket. This trier is used for drawing seed samples from the seed lots packed in bags or in containers.