Abstract Detail

Economic Botany Section

Salywon, Andrew [1], Dierig, David [1], Rebman, Jon [2], Jasso de Rodriguez, Diana [3].

Evaluation of new Lesquerella and Physaria (Brassicaceae) oilseed germplasm.

The seeds of species of Lesquerella and the closely related genus Physaria (Brassicaceae) contain hydroxy fatty acids (HFAs), (either auricolic, densipolic, or auricolic), as the main constituent of their seed oil. HFAs are used in the production of a variety of industrial products, cosmetics and pharmaceuticals. Currently the only commercial source of HFAs is castor oil, which is imported. Lesquerella fendleri (Gray) Wats. is being developed as a new crop for arid regions of the southwestern United States as an alternative source of HFAs. In order to meet desired objectives of improved oil yield and quality for our breeding program and to discover related species with potential for domestication, an effort was made to increase available germplasm from wild populations. From 1995 to 2001, 81 accessions from 28 species of Lesquerella were collected in the United States and 32 accessions from four species were collected in Mexico, and 39 accessions from 13 species of Physaria were collected from the southwestern U.S. Mean seed mass ranged from 0.54 to 2.30 mg for Lesquerella compared to 1.7 to 5.8 mg for Physaria. Seed oil content highs ranged from 32.2 % in Lesquerella to 35.4 % in Physaria. The fatty acid profile of all species of Physaria and most of the lesquerolic acid-rich species of Lesquerella contained from 30-55 % lesquerolic acid, although several species contained more than 60 %, with differences between high and low HFA yielding species related to the ability to include HFAs at all three positions of the triacyglycerol molecule or only at the sn-1 and sn-3 positions. These collections of wild germplasm provide a diverse gene pool from which traits can benefit our breeding program to produce a domestic source of HFAs.

1 - U. S. Water Conservation Laboratory, USDA-ARS, 4331 E Broadway Rd, Phoenix, Arizona, 85040-8807, USA
2 - San Diego Museum of Natural History, P.O. Box 121390, San Diego, California, 92112-1390, USA
3 - Universidad Autonoma Agraria Antonio Narro, Buenevista, Saltillo, Coahuilla, 25315, Mexico

Keywords:
hydroxy fatty acids
germplasm
Lesquerella
Physaria
new crops
seed oil
Brassicaceae.

Presentation Type: Paper
Session: 21-3
Location: Maybird (Cliff Lodge)
Date: Monday, August 2nd, 2004
Time: 2:30 PM
Abstract ID:698