1. Green Field is a synthetic
variety with 137 parent clones. Parent clones trace to 26 populations selected
for resistance to the following pests: bacterial wilt, Fusanum wilt, Verticillium
wilt, Phytophthora root rot, anthracnose and Aphanomyces. Phenotypic recurrent
selection was used. Final selections were made from 2-year-old space-plant
selection nurseries at Marshfleld and Livingston, Wisconsin, based on vigor,
leafhopper yellowing resistance, leaf disease resistance, winter injury
and fall dormancy reaction.
Parentage traces to Nordic
(14%), Venture (11%), Exp AP 8734 (1O/.), Exp AP 8822 (9%), Genesis
(6%), Cutter, Aggressor, Dominator and Gsrst 645 (5% each), Trident II,
Stine 9227, Horizon and Exp AP 45 (4% each), Exp AP 47 (3%), with 11% coming
from numerous other sources. Approximate germplasm source contributions
are: Mj~La (8%), Ladak (8%). M. vana (20), Turkistan (15%), Flemish (31%),
Chilean (8%), Peruvian (4%) and 6% unknown.
2. Green Field appears to be adapted to and is intended for use in the North Central U.S. It has been tested in Wisconsin, Iowa, Idaho and Pennsylvania.
3. Fall dormancy of Green Field is similar to Ranger. Flower color of Syn 2 generation is approximately 700/. purple and 300/. variegated, with a trace of cream, white and yellow.
4. Green Field has high resistance to bacterial wilt, Fusarium wilt, anthracnose (race 1), Phytophthora root rot and pea aphid, and resistance to Verticilhium wilt and Aphanomyces (race 1). Reaction to stem nematode, spotted alfalfa aphid, blue alfalfa aphid and root knot nematode has not been determined.
5. Seed increase is limited to one generation each of breeder (Syn 1), foundation (Syn 2) and certified (Syn 3) seed classes. Certified seed may be produced from either breeder or foundation classes. A 1, 3 and 6-year stand life is permitted on fields producing breeder, foundation and certified classes respectively. Foundation seed production is limited to the Pacific Northwest. Breeder seed was produced in 1990. ABI will maintain sufficient seed stocks for the projected life of the variety.
6. Certified seed will be available in 1993.
7. Plant Variety Protection will not be applied for.
8. This information can be
forwarded to the PVP office.