Seed classes through Generation system of seed multiplication

How often do we see a potential life as seed? How often do we have a medium even close to the life-nurturing ability of soil? Not so frequent, right? Maybe never.

You might be wondering how come this blogger fellow decides to take philosophy class in here. Well, this is just to remind you that seed is the source and regulator of green life. But guess what, this can also have a clear impact on your health.

When a seed is infected (or infested as we say) with any kind of microorganism, it shows up in the developed plant body. These kind of diseases are called seed borne diseases. In fruits, in cereals and in vegetables seed borne diseases are common. This can alter the physiological processes of plant life and can also have detrimental effects on the fruit or grain quality.

Due to this, seeds must be authenticated before putting into the soil.

There are several agencies and institutions which recognize and tags seeds according to several parameters like, viability, genetic purity, genetic potential, weight, moisture content etc.

In here, we shall discuss a detailed description of the parameters, institutions and classes of seeds.

At first, let’s jump into the system by which seeds are produced. The system of producing seeds is called generation system of seed multiplication. Let’s dive deep.

Generation system of seed multiplication is nothing but the production of a particular class or type of seed up to certified seed stage.

There are several models of seed multiplication. Choosing the right model for production of particular type of seed is the key to success. The choice basically depends upon,

• The rate of genetic deterioration
• Seed multiplication ratio and
• Total seed demand

At the very outset of the production system, when a new cultivar is introduced, normally a small quantity of seed (known as the nucleus seed) is available with the breeder. After this  the multiplication goes like-

Three generation model	Breeder seed – Foundation seed – certified seed
Four generation model	Breeder seed – Foundation seed (1) - Foundation seed(2) – certified seed
Five generation model	Breeder seed – Foundation seed (1) - Foundation seed(2) – certified seed(1) – certified seed (2)

Now let’s talk about the real core; the classes of seed. How many classes are there in seeds? Is it stubborn like classes we have in our society? Do the upper class seeds talk badly or call the lower class seeds down? Well, the “seed classism” goes like this-

Nuclear seeds:

• Hundred percent genetically pure
• Physical purity is maximum
• Produced by original breeder/ institution/ SAUs
• Produced from basic nuclear seed stock
• A pedigree certificate is issued by the producing breeder

Breeder seed:

• A progeny of nuclear seed multiplied in lagre area
• This is also holds total genetic and physical purity
• Golden yellow coloured certificate is issued by the breeder
  

  

Foundation Seed:

• Progeny of breeder seed produced by recognized seed producing agencies
• Produced under the supervision of seed certification agencies
• Quality of seed is maintained according to field standards
• A white coloured certificate is issued.

Registered seed:

• Progeny of foundation seeds
• Genetic identity and purity is maintained here
• A purple colored certificate is attached
  

  

Certified seed:

• This seeds are the progeny of foundation seed
• Produced by recognized growers
• This production is done under the supervision of the seed certification agencies
• Maintainance of quality is as per minimum seed certification standards
• Azure Blue colored certificate is issued
  

  

Other than these, there is another type of seed rather popular amongst farmers. This seed is called Truthfully Labeled Seed or TLS. Attributes of this kind of seed are-

• This can be a progeny of the foundation seeds, certified seeds, labeled seeds
• Field standard and production is same as certified seed
• In this case, no certification agency is required
• Market monitoring is the only quality testing tool
  

  

By the forewritten attributes you maye have noticed that TLS and Certified seeds are quite similar. But they have some serious differences coming up-

Certified seed	Truthful Labeled Seed (TLS)
Certification is voluntary	Truthful labeling is compulsory for notified kind of varieties
Applicable to notified kinds only	Applicable to both notified and released varieties
It should satisfy both minimum field and seed standards	Tested for physical purity and germination
Seed certification officer, seed inspector can take samples for inspection	Seed inspectors alone can take samples for checking the seed quality

Now, let’s look into the seed multiplication ratio of different cops. seed multiplication ratio is nothing but the number of seeds that can be produced from a single seed. It is basically the seed to seed journey scenario. The figures are given by expert group of seeds (1989). Don’t be afraid. You need not even intend to remember them. Just have a look to develop a basic outline of the concept.

• Wheat 1:20
• Paddy 1:80 (varieties) 1:100 (hybrids)
• Maize 1:80 (varieties) 1:100 (hybrids)
• Sorghum 1:100
• Bajra 1:200
• Gram 1:10
• Black gram 1:40
• Green gram 1:40
• Cowpea 1:40
• Moth Bean 1:40
• Red gram 1:100
• Cole crops: 1:433
• Potato 1:4
• Ground Nut 1:8
• Linseed 1:50
• Cotton 1:50
• Jute 1:100
• Mestha 1:40
• Sunhemp 1:30
• Berseem 1:10
• Lucerne 1:25
• Oats 1:15
• Bhendi 1:100
• Tomato 1:400
• Brinjal 1:450
• Chillies 1:240
• Watermelon 1:100
• Pumpkin  1:160
• Bitter gourd 1:41
• Bottle gourde 1:99
• Ridge gourde 1:83
• Cumumber 1:200
• French bean 1:9
• Onion 1:171
• Radish 1:100
• Carrot 1:83
• Mustard rapeseed 1:100
• Soybean 1:16
• Sunflower 1:50
• Sesame 1:250
• Safflower and castor 1:60

Ever wondered why papaya seeds are so glossy and slippery? Click here to know

(*Picture courtesy: TNAU Official Portal)