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

Introduction

• Sound seeds may be distinguished from inert matter, sterile and empty seeds by size and shape, specific gravity, colour and surface texture.
  
• Processing has well been mechanized and based on the physical characters of seed, separate machines are available for grading and upgrading, and these machines can be used either singly or in combination.
Physical characteristics of seed and the processing equipments available for grading

1	Size	:	Based on size it can be separated with air screen cleaner cum grader
2.	Length	:	Disc or indented cylinder separator
3.	Weight	:	Specific gravity separator
4.	Shape	:	Spiral separator or draper separator for round and flat seeds
5.	Surface texture	:	Rough from smooth surface seed-dodder mill
6.	Colour	:	Electronic colour separator
7.	Electrical conductivity	:	Seed differing in their ability to conduct electrical charge can be separated with electronic separator