**3. Production and management of quality potato seeds**

The usual way to spread potatoes all over the world is by vegetative way through whole or fragmented tubers. The latter is only practised in a few European countries and in North America [3, 10].

Through this vegetative production from generation to generation, seed tubers can be infected with a high number of viral, bacterial and fungal diseases, and thus seriously affect the growth and production of the plantation. This is the reason why the production of quality seeds, storage and related legislation are discussed in the following pages

At the harvesting time, the seed tubers are usually dormant and do not present growing buds even if the ecological conditions are favourable.

#### **3.1 Characteristics of potato quality seed**

Many factors determining yield are affected by seed quality. Good quality seed is obtained when the seed tubers are harvested on a seed field in good condition, dry before the formation of the tubers has been naturally completed and harvested shortly after dehaulming. Quality tuber seed should be able to produce healthy and vigorous plants within the growing season. Seed quality is determined by the following parameters [6, 10]:

