Low-palmitic, low-linolenic soybean development

Plant breeding research efforts are currently focused on developing breeding procedures to decrease the saturated FA palmitic acid (16:0) and the PUFA linolenic acid (18:3) in U.S. soybean cultivars. Soybean oil with lower 16:0 may provide cardiovascular benefits to health-conscious consumers, and lower 18:3 could contribute to better flavor and stability of the oil. The purpose of this study was to determine genetic parameters that indicate the potential for breeding success and to characterize the correlated effect of the incorporation of the modified oil traits on the agronomic and seed quality traits of a soybean breeding population formed from a cross between the soybean cultivar Anand (normal) and germplasm N97-3708-13 (low 16:0, low 18:3). Although lines with only one modified oil quality trait (low 16:0 or 18:3) are useful as parents, commercial utilization requires productive cultivars with the combination of both oil traits. This paper shows the ease with which they may be combined with seed yield and other traits. Measurements were obtained from 179 F-2 single plants grown in 1999 and 121 F-2.4 lines grown in replicated plots in 2000. Modified FA lines were developed with ca. 4% 16:0 and 18:3. respectively. Very weak positive correlations were found between 16:0 concentration and seed yield (r = 0.12) and between 16:0 and seed oil concentration (r = 0.13). No correlation was found between 18:3 levels and seed yield, or between 18:3 levels and seed oil concentration. These results indicate that breeding for reduced 16:0 and 18:3 should not have a negative impact on seed yield or oil concentration. 16:0 and 18:3 had moderately high heritabilities of 0.65 and 0.73, respectively. This indicates that breeders using low 16:0, low 18:3 germplasm in crosses with normal, elite lines can expect to recover low 16:0 and low 18:3 in pure line progenies via selection and generation advancement of F-2 individuals that express low levels of these FA.