Rio

1. Rio was bred from the following germplasm sources: BAA-15=8.3%, BAA17=8.3%, BAA-20=8.3%, UC123=12.5%, UC143=12.5%, CimarronVR=50%. The breeding procedure was recurrent selection for resistance to Phytophthora root rot, anthracnose, spotted alfalfa aphid, pea aphid and blue alfalfa aphid in the above sources, followed by strain crosses. The germplasm is estimated to have come from African (45%), Chilean (23%), Flemish (15%), M.varia (10%), Turkistan (5%), M.falcata (1%), and Ladak (1%).

2. Areas of probable adaptation and use are the Sacramento and San Joaquin valleys and the Southern United States. Rio is to be used for hay, haylage and greenchop. Rio has been tested for yield and persistence in California and Georgia.

3. Rio has a fall dormancy rating of 7. Flower color is predominantly purple (94%) with a low frequency of blue (6%).

4. Rio is highly resistant to race 1 anthracnose, Phytophthora root rot, Fusarium wilt, pea aphid, spotted alfalfa aphid, and blue alfalfa aphid; resistant to bacterial wilt, root knot nematodes, and race 2 anthracnose; and moderately resistant to stem nematode and Aphanomyces. Verticillium wilt resistance has not been evaluated.

5. Seed increase is on a limited generation basis with one generation each of breeder, foundation, and certified seed classes: i.e., Breeder (Syn1), foundation (Syn2), certified (Syn3). Breeder seed was produced under isolation in Apex, NC. Foundation and certified classes are produced by Great Plains Research Company, Inc. under contract with seed growers. Age of stand for seed production for breeder, foundation, and certified is 1, 2, and 6 years, respectively. Breeder and foundation seed stocks are maintained by Great Plains Research Company, Inc.

6. Certified seed will be marketed in 1992.

7. Application will be made for Plant Variety Protection under the act. The certification option will not be requested.

8. This information can be forwarded to the PVP office.