54H55

1. 54H55 is a variety developed to resist a new biotype of blue aphid (BA2 and or BAOK90) endemic to the south central part of the U.S. Using phenotypic recurrent selection since 1991, pre-breeder parental germplasm was selected for resistance to the new biotype of blue aphid (BA2). Plants used for breeder seed (syn1) production were from Phytophthora root rot, stem nematode, and northern root knot nematode screenings.

2. 54H55 is adapted and intended for use in the east central, winter hardy intermountain and moderately winter hardy regions of the United States where blue aphid is present. The states in which 54H55 has been tested are: Iowa, Oregon, Washington, Wisconsin, and Ontario, Canada.

3. 54H55 is a moderately dormant cultivar with a fall dormancy similar to FD-5 check. Flower color in the syn1 generation is approximately 94% purple and 6% variegated, with traces of yellow, white and cream.

4. 54H55 is highly resistant to bacterial wilt, stem nematode, northern root knot nematode, Phytophthora, root rot, Verticillium wilt, pea aphid, and spotted alfalfa aphid; and resistant to Anthracnose (race 1), Fusarium. wilt, and blue aphid. Aphanomyces root rot (race 1) has not been tested.

5. Breeders seed (syn1) was produced on 22.5 selected parent plants in a 1996 cage isolation and bulked. Seed classes will be breeder, foundation (syn2 or 3), and certified (syn2, 3, or 4). Foundation seed may be produced from breeder or foundation. The second generation foundation seed may be produced at the discretion of Pioneer Hi-Bred International, Inc. Limitations of age of stand will be three and five years, respectively, for foundation and certified seed. Pioneer Hi-Bred International, Inc. will maintain sufficient breeder seed and foundation seed for the projected life of the variety.

6. Certified seed will first be marketed in January 2000.

7. Application for Plant Variety Protection has been made, and the certification option was not requested.

8. As a means of added, varietal protection, information with the Application for Review of Alfalfa Varieties for Certification may be provided to the PVP office.

9. Variety name: 54H55

Date submitted: November 30,1999

Experimental designation: X54H55, Y54H55, 96N04PL1