Synthetic variety can be developed from well established and tested inbred lines or from S0 or S1 plants
Development or Production of Synthetic Variety from established Inbred lines
- Inbreds are selected at the starting
- Those are crossed with common tester (top crossing) to test combining ability
- Seeds from the crosses are harvested separately
- Replicated yield trials to evaluate these top crosses with check (either OPV or standard hybrid)
- Identification of inbred lines with good general combining ability (gca) (on the basis of performance in above crosses)
- All possible single crosses among selected inbred lines are made and seeds are harvested separately
- Seeds from single crosses are mixed in equal quantity
- Seed multiplication by open pollination with isolation, for one or two generation
- Variety release
Development or Production of Synthetic Variety from plants
- Isolation of one generation selfed lines
- Evaluation of these lines for gca and also their testing for yield and other characteristics (in top cross trials)
- Inter-mating of inbreds with good gca (either by single cross, top cross or poly cross)
- Seeds harvested separately
- Seed multiplication for distribution
Examples of Synthetic Variety
Bajara – ICMS-7703
Coconut – PCA SYN VAR 001
Visit the link New Crops Newsletter. This will give some additional information on the topic.