COLLECTION AND EVALUATION OF NEW LESQUERELLA AND PHYSARIA GERMPLASM

Lesquerella and the closely related genus Physaria are prime candidate s as a new, alternative source of hydroxy fatty acids (HFA) for indust rial uses. At present, castor oil is the only natural source of these HFA for commerce. To expand the germplasm base of these taxa for our b reeding program and the National Germplasm System (NPGS), we collected species from a wide geographic region in the United States. Ih 1993, 44 accessions of Lesquerella fendleri, 38 accessions from nine other L esquerella species, and three accessions' of two different Physaria sp ecies were obtained. In 1994, 41 additional accessions of L. fendleri and 51 accessions of ted other Lesquerella species were collected. A t otal of 20 different species of Lesquerella and two Physaria species w ere collected over the two years. Oil characteristics and seed size of eight of these Lesquerella and one Physaria species have not previous ly been reported. Twelve of these taxa have not been available in the NPGS. Populations of L. fendleri collected in Arizona had higher seed- weights than those collected from Texas and New Mexico. Some of the ne w accessions had seed-weights higher than germplasm presently in the U SDA-ARS breeding program. Diverse growth habits were found in populati ons from all three states. We believe that other species of Lesquerell a and Physaria could later be developed as a source of HFA in regions other than the arid southwestern United States. Accessions of Lesquere lla douglasii had the same or higher seed-oil content than L. fendleri and also higher seed yields. Two accessions of Physaria newberryi had seed-weights that ranged between 4.5 and 6.2 g/1000 seeds compared to that of 0.25 to 1.1 g/1000 seeds for L. fendleri. Seed-oil contents o f P. newberryi averaged 30.8% compared to 23.8% for L. fendleri. Preli minary seed increase and evaluation of oil content and composition wer e completed on 14 L. fendleri populations from the 1993 collection und er field conditions in Phoenix, Arizona. Accessions were compared to t he original populations collected in 1993 and 1994 for growth habit, s eed size, and seed-oil content and quality.