Temperature and elevation effects on plant growth, development, and seed production of two Lesquerella species

A potential new alternative oilseed crop from the genus Lesquerella is being domesticated for the southwestern United States and other and climates of the world. This crop has seed oil rich in hydroxy fatty acids used to produce a variety of industrial, cosmetic, and pharmaceutical products. Many of the industrial products are replacements for non-degradable and non-renewable petroleum-based products such as hydraulic fluids, surfactants, 2-cycle engine oils, automotive oils, protective coatings, drying agents, and plastics. L. fendleri is the main species being utilized for crop development, although other species are being utilized for introgression of useful traits into L. fendleri. The objective was to determine field sites suitable for crop production. Two species, L. fendleri and another we refer to as 'L. pallida aff.' because it differed from typical L pallida plants in chromosome number and in oil quality, were planted in the fall of 2003 at various sites in Arizona that ranged in elevation from 300 to 1200 m asl, and -13.2 to 38.8 degrees C in temperature over the growing season. The four sites included Phoenix, Tucson, Safford, and Patagonia. Plants of L. fendleri developed flowers and fruits by the week of 21 March at Phoenix and Tucson, but one month later at the two higher elevation sites. Plant height, width, and biomass measured during the season indicated that plants at the two lower elevations grew nearly two times taller and wider, and over five times the biomass of the plants at the higher elevations. Seed yields followed the same trend. However, oil contents were very similar over the four elevations. Plants of L pallida aff. were almost all flowering and fruiting by 04 April at Tucson, two weeks later at Phoenix, and not until 02 May at the two higher elevations. Plants were tallest and widest throughout the season at Tucson until final harvest. Plants at Patagonia at final harvest were as tall and wide, had greater biomass and seed yields than Tucson and Phoenix. These results indicate that L. fendleri is suitable for production in areas below 700 m. Plants of L. pallida aff. were more productive at the highest elevation of 1219 m. It was not entirely clear as to how plants of either species would have performed at the 884 m elevation site due to high plant mortality at the early growth stage. Results indicate that production areas for L. fendleri may be expanded with the introgression of genes from L. pallida aff. (C) 2005 Elsevier B.V. All rights reserved.