INTRODUCTION TO PLANT BREEDING

AGRONOMY 815 / COURSE NOTES

P. STEPHEN BAENZIGER, 338 Keim Hall, 472-1538

DEPARTMENT OF AGRONOMY / UNIVERSITY OF NEBRASKA

SYNTHETIC VARIETIES

Synthetic variety = the advanced generations of open-pollinated seed mixtures of a group of strains, clones, or inbreds, or of hybrids among them.

Most extensively utilized in forage crops, but also in corn, sugar beets and other cross-pollinated crops.

PROCEDURE FOR DEVELOPMENT OF A SYNTHETIC:

1. Reproducible units, such as clones (forages) or inbreds (corn or sugar beets) are selected on the basis of performance in combining ability tests.



2. These selected 'units' are intercrossed -- SYN-0.



3. Equal quantities of seed harvested from each intercross are bulked and grown as the first generation synthetic -- SYN-1.



4. Open pollinated seed of SYN-1 is harvested -- SYN-2 , etc.

In order to maintain the original level of vigor, synthetic varieties need to be reconstituted regularly.