REGISTRATION OF DESERET ALFALFA
Crop Sci. 17: 671 (1977)

M. W. Pedersen and G. D. Griffin

`Deseret' alfalfa (Medicago sativa L.) (Reg. No. 78) was developed cooperatively by the ARS, USDA, and the Utah Agricultural Experiment Station. Deseret was tested as Utah 5045, and released in April, 1975 as `Kayseri'. The name was changed to Deseret in September, 1975 because of the prior usage of Kayseri.

Deseret was developed from two cycles of phenotypic recurrent selection in the greenhouse for stem nematode [Ditylenchus dipsaci (Kuehn) Filip] resistance in a plant introduction from Turkey (P.I. 279 958). Approximately 150 stem nematodes resistant plants were selected from a population of 2,500 plants. The resistant plants were interpollinated by leaf cutter bees in a field cage. The procedure was repeated in a second cycle of selection.

Deseret is a tall, high-yielding cultivar with dark green foliage and flowers that vary from nearly white to purple. Bacterial wilt resistance [Corynebacterium insidiosum (McCull.) H. L. Jens.] and cold tolerance of Deseret are about like `Ranger', but stem nematode and downy mildew resistance (Peronospora trifoliorum de Bary) are considerably better than Ranger. Deseret is susceptible to both pea aphids [Acyrthosiphon pisum (Harris)] and spotted alfalfa aphids [Therioaphis maculata (Bucton)]. The saponin concentration of Deseret (per bioassay) was lower than that of Ranger and `Dupuits' when tested in vitro, but similar to Ranger, `Lahontan', and DuPits when tested with sheep. Deseret is adapted to irrigated areas in the intermountain region where conditions are similar to northern Utah.

Seed produced from the second cycle of screening will constitute breeder seed and will be maintained at Logan, Utah. Three generations of increase beyond breeder (foundation, registered, and certified) will be permitted. The production of foundation and registered seed shall be restricted to Idaho, Oregon, Washington, and the northern half of Utah and Nevada. Deseret was favorably reviewed in 1974 by the National Certified Alfalfa Variety Review Board.