Steps involve in Seed processing

Seed technology

1. P r i n c iples of S e ed T echnology T o p ic - S t e p s i n v olve i n s e e d p rocessing S u b m itted t o - S u b mitted b y D i n e s h

2. O u t l ine I n t r oduction A d v a n t ages S e e d p rocessing s t eps p r e c o n d ition ing and p r e cleaning C l e a n ing G r a d i ng and c l e a n ing

3. I n t r oduction Seed processing is a vital part of the seed production needed to move the improved genetic materials of the plant breeder into commercial channels for feeding the rapidly expanding world population. The farmer must get the quality seed that is free from all undesired materials because farmers entire crop depends on it. Seed processing is that segment of the seed industry responsible for upgrading seed (Fig. 1), improving planting condition of seed, and applying chemical protectants to the seed.

4. A d v a n t a ges Make possible more uniform planting rates by proper sizing Improve seed marketing by improving seed quality Prevent spread of weed seed Prevent crops from disease by applying chemical protectants Reduces seed losses by drying Facilitate uniform marketing by providing storage from harvest time until the seed is needed for planting.

5. S t e p s i n volve in seed processing S t e p 1 - Pre-conditioning and p r e - c l e a n i n g Step 2 - C l e a n ing S t e p 3 - C l e a n i n g and G r a d ing

6. S t e p - 1 - P r e c onditioning and p re cleaning Pre conditioning: - Isolation of seed from plant parts with which it was harvested . e.g. Shelling Pre cleaning : - Removal of external materials like trash, stones, clods which are either in larger size or lighter in weight. No pre cleaning is required for hand harvested and winnowed seeds

7. S e e d Scalper It removes the larger inert matter from the seeds. If it contains a single sieve it is called as scalpers, two sieves – rough cleaners. The unit consists of a vibrating or rotating screen or sieve having perforation large enough to allow the rough seed pass through readily.

8. D e b e a r ders The machine has horizontal beater with arms rotating inside a steel drum. When the seeds pass through it do the action of rubbing the seeds and clip the seeds of oats, debeard barley, thresh white cap in wheat, remove awns and beards, de hull some grass seeds and polish the seed.

9. O t her e q uipment s Huller – scarifier

Have two rubber faced rough surfaces to rub the seeds. Dehulling (removal of outer coat or husk) and scarifier (scratching the seed coat) can be done simultaneously or separately. Its operations,
Seed – rotating disc- centrifugal force – thrown – huller- - suction chamber- removes lighter seeds .
Maize sheller

1. High capacity power operated shellers - bulk
2. Hand shellers – breeder or nucleus seed.

10. S t e p - 2 - C l e a n ing The second stage of cleaning is carried out with air blasts and vibrating screens and is applicable to all kinds of seeds. It is essentially the same as scalping but more refined. It is performed mostly by one machine known as air-screen cleaner.

11. A ir-Screen cleaner cum grader The air-screen machine is the basic cleaner in most seed processing plants. Almost all seed must be cleaned by air-screen cleaner before specific specifications can be attempted. Machine size varies from small, two-screen farm models to large industrial cleaners with 7-8 screens

12. S t e p - 3 - C leaning a nd Grading To obtain quality seed, it is necessary to clean the seed obtained from the farm to get rid of inert materials, weed seeds, other crop seeds, other variety seeds, damaged and deteriorated seed. Different kinds of seeds can be separated when they differ in one or more physical characteristics. Physical characteristics normally used to separate seeds are size, shape, length, weight, colour, surface texture, affinity to liquids, electrical conductivity, etc. The problem lies in identifying the most important property and use the machine that separates seed using the identified property.

13. upgrading S e e d lots require further cleaning treatment to remove adulterants that are similar to pure seed in size and shape, to be separated by air screen cleaner. Removal of seeds larger or smaller than required size (sizing) and removal of cracked, damaged or otherwise defective seeds (grading) is accomplished in this final stage of processing.

14. Some of the identified properties and machines operating by following the properties are listed below:

15. S p e c ific G r avity separator T h is method makes use of a combination of weight and surface characteristics of the seed to be separated

16. S p i r a l s e parator T h e separator, which classifies seed according to its shape and rolling ability, consists of sheet metal strips fitted around a central axis in the form of a spiral.

17. O t her u s eful e q uipment s C o l our s e parator M a gnetic separator I n t e n ded c y l inder e t c . T H A NKS Y OU