Three seed systems are considered:
The role of and the relation between the formal and the non-formal system depends on the agro-economic situation.
- formal system
- commercial system
- non-formal system
The seed from the formal seed system enters into the non-formal seed systems such as:
farmer's own seed, small sized tubers from markets, neighbours, traders, etc.
In the non-formal systems there are many variations, but some common approaches apply:
- large tubers are used or sold as table potatoes and small tubers find their way as seed
- good seed stocks are used for several generations and only renewed from to time
- seed from the non-formal system is cheaper than formal seed
- non-formal seed is found near the user
- farmers using own seed do not need cash or credit to buy seed
- suppliers of
non-formal seed often have credit facilities for the buyer of the seed (e.g. seed supplier provides 1 bag of seed at planting time and receives 2 bags of consumer potatoes at harvest time of the crop)
In the formal and commercial system seed is produced by specialized units, following a well described system and quality control regulations.
Quality control system may include certification and/or quality labels provided by the seed producing organization.
The seed from the specialized formal system has a high quality, but is relatively expensive.
The formal seed often retains a sufficiently good quality for several generations.
Two different types of seed are:
- Pre-basic and basic seed
- Certified seed or commercial seed