After the production of seed, its multiplication for distribution involves following.
Nucleus Seed
Nucleus seed is the initial amount of pure seed of improved variety or notified variety or parental lines of a hybrid produced under supervision of the evolver of that variety.
The nucleus seed generally 100% pure and does not contain other physical impurities. It is produces strictly under isolation to avoid both genetical and physical impurities. Vigour of the original variety or parental line should be retained in nucleus seed.
About 500 to 1000 individual plants (IPS) which are healthy and have vigorous growth are selected from the nucleus bulk-plot before onset of flowering. Observations are recorded on each IPS for important and easily observable morphological characters like plant height, stem color, branching. The IPS which are off types or affected from seed born diseases are removed. Separate harvesting of the individual IPS is carried out. Seeds are stored in separate cloth bags or paper bags with proper labeling.
Breeder Seed (Stage I and Stage II)
It is the progeny of nucleus seed.
Generally breeder seed is produced in one stage. But for the reasons like greater demand or low seed multiplication ratio then breeder seed can be produced in two stages, viz. breeder stage I and II.
For stage II source of seed is stage I. Breeder seed can be produced by original breeder, sponsored plant breeder on Agricultural University farms and rarely on government farms.
Some of the standards set for breeders seed are genetic purity 99.9% or more, physical purity 98% or more, germination (as per crop) moisture content less than 12%.
Seeds are stored in bags with buff color tags.
Foundation Seed (Stage I and Stage II)
It is the progeny of breeder seed.
Can be produced in two stages viz. stage I and stage II.
Foundation seed is produced on the farms of State Agril. Universities, Taluka Seed Farms, other government farms, State Seed Corporations and private seed companies.
Genetic purity is 99.5% or more.
Seeds are stored in bags with white color tags.
Registered Seed
It is the progeny of foundation seed.
It is produced by progressive farmers or registered seed growers according to technical advice and supervision provided by NSC.
Registered seeds are genetically pure.
Seeds are stored in bags with purple color tags.
Certified Seed (Stage I and Stage II)
It is the progeny of foundation seed.
Genetic purity is 99% or more.
Seeds are stored in bags with blue color tags.
Truthful Seed
It is the category of seed produced by private seed companies and is sold under truthful labels.
Companies should maintain field and seed standards suggested for quality seed production as per seed act.
Seeds are stored in bags with opel green color tags.
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