1. Seed-propagated cultivars (terms and definitions)
a cultivar is a group of plants with traits that are distinct, uniform, and stable
distinct: 1 or more identifiable traits
uniform: variation among plants can be described
stable: traits remain unchanged (in essential distinctness and uniformity) when reproduced or reconstituted

2. Types of seed-propagated cultivars (Fehr’s classification)
lines
open-pollinated (OP) cultivars
synthetics
hybrids (F1 hybrids)
F2 cultivars
multilines

3. Line cultivars
are maintained by selfing or sibbing
are highly uniform, “crossers” may lack vigor
may be natural self pollinators (‘Tendercrop’ snap bean) or cross-pollinated species (‘Nittany Lion Red’ geranium)
highly apomictic cultivars are considered pure lines; e.g., ‘Merion’ Kentucky bluegrass

4. Open-pollinated cultivars
are normally cross-pollinated plants; some variation is expected
have 1 or more distinguishing traits; e.g., ‘Thumbelina Mix’ zinnia
are inexpensive to produce, are self perpetuating

5. Synthetic cultivars
Syn 1 cultivar (1st gen. progeny) from intercrossing a set of clones or lines
can’t be reproduced from seed of Syn 1
Syn 2 is by open pollination of Syn 1
provide some pest/disease resistance by their genetic diversity

6. Hybrid (F1) cultivars
1st generation (F1) progeny from crossing, e.g., 2 inbred lines (single cross)
pollination control is an important factor
are highly uniform, often exhibit ‘hybrid vigor’, but are more expensive
can’t be reproduced from F1 seed

7. F2 cultivars
OP field production of an F1 hybrid
can’t be perpetuated by seed of F2
are much cheaper than F1 hybrids, but are more variable

8. Multiline cultivars
a seed mixture of cultivars or lines
typically, component lines are grown separately, then composited
are often used in the flower seed industry for flower color mixes