1. CW 3666 is a synthetic variety with 250 parent plants which were selected sequentially for resistance to Phytophthora root rot and Anthracnose (race 1). Parent plans were selected from crosses between selections from four year old California yield trials and various populations developed by a combination of phenotypic recurrent selection and strain crossing with selection for one or more of the following pests: Fusarium wilt, Verticillium wilt, anthracnose (race 1), Phytophthora root rot, blue alfalfa aphid, and spotted alfalfa aphid. Parentage of CW 3666 traces to the following germplasm sources: Express, VS-626, Condor, Mede, Yolo, and DK 187. Approximate germplasm source contributions are as follows: M.falcata (1%), Ladak (2%), M.varia (8%), Turkistan (17%), Flemish (26%), Chilean ( l l¡/0), Peruvian (2%), Indian t9%), African (18%), and Unknown (6%).
2. CW 3666 is adapted to the Southwestern and Moderately Winterhardy Intermountain areas of the U.S. and Mexico, and is intended for use in the Southwestern and Moderately Winterhardy Intermountain areas of the U.S., Mexico, and Argentina. CW 3666 has been tested in California, New Mexico, and Mexico.
3. CW 3666 is a moderately dormant variety with fall dormancy similar to ABI 700. Flower color observed in the Syn.2 generation is greater than 99% purple with a trace of variegated and cream.
4. CW 3666 has high resistance to anthracnose (race 1), Fusarium wilt, Phytophthora root rot, stem nematode, spotted alfalfa aphid, and pea aphid, resistance to Verticillium wilt and blue alfalfa aphid, and moderate resistance to bacterial wilt. Reaction to Aphanomyces root rot (race 1) and root knot nematode has not been adequately tested.
5. Seed increase of CW 3666 is on a limited generation basis with one generation of breeder and two generations of the foundation, and certified seed classes. Breeder (Syn l), foundation (Syn.2 or Syn.3), and certified (Syn.3 or Syn.4)classes will be recognized. Production of Syn.3 foundation seed requires the consent of the breeder. Breeder seed was produced under cage isolation at Woodland, California in 1993. Sufficient foundation seed for the projected life of the variety will be maintained by Cal/West Seeds. Stands of foundation and certified seed fields are limited to 3 and 6 years, respectively.
6. Certified seed of CW 3666 will be available in 1997.
7. No decision has been made regarding Plant Variety Protection.
8. This information can be forwarded to the PVP office.
9. Variety Name: . Date submitted: 12/1/96. Experimental Designation: CW 3666 .