Plant breeding is a time-consuming and expensive work. Depending on the species, around 8-15 years are required from the start of the breeding program until a new variety can be sold on the market.
The steps of a breeding program:
- identification of qualities for improvement
- selection of parents
- creation of variation through e.g. crossings
- repeated selections according to different methods
- test of promising plant material on test sites
- official testing, propagation of seed and marketing.
An example - peas
For the breeding of peas, the possibility to grow one generation in Sweden during the summer and then the next generation in Chile during the winter the same year is used. That way, the breeding program is accelerated and will take less time than for a winter crop.
Year 1 New characteristics are identified in plant material. Raising of plants in greenhouse.Crossing between plant material with favourable properties.
Year 2 The results from the crossings are sown in greenhouse for seed production.
Year 3 In March-April the seed is sown in rows in the field. Both agronomic and qulity characters like e.g. stalk stiffness, time of ripening and resistance to diseases are judged in the field. The best plants are harvested individually. The seed is then sent directly to Chile and are grown there during the winter. The breeder also scores the plants in Chile and seeds from the best ones are sent back to Sweden at the end of February the same year.
Year 4 New tests and selections in Sweden and Chile in the same way as for year 3. In Chile the seed is sown in bigger plots (10 m2) to facilitate the multiplication.
Year 5 Comparative tests in Sweden and France of the different lines selected from the original crossing. After yield, disease resistance, growing mode etc. having been evaluated, only about 40% of the plants continue to the next step of the breeding.
Year 6 The seeds from the remaining plants are sown in plots in Sweden, France and Canada. At the same time, isolation is made of about 5 plants from each potential variety to produce seed for the official variety trial.
Year 7 The plant material is tested and evaluated as before as well as in trials at breeding stations. Only the lines found competitive to the varieties of the market are saved in the trials. Early seed multiplication now takes place in parallel into the continued selection.
Year 8 Official variety test of potential varieties and application for plant breeders’ rights. Seed production, marketing and selling of a registered variety. Out of the thousands of lines arising from the original crossings, only a few are left to be approved varieties that can be sold on the market.