A Novel Soybean Germplasm with Elevated Saturated Fatty Acids

Abstract

Two soybean [Glycine max (L.) Merr.] germplasm lines have been identified for unique fatty acid content. The very high content of palmitic acid in HPKKJ10 is controlled by the fap2 and fapx loci, and the very high content of stearic acid in M25 is controlled by the st2 locus. If the fap2 and fapx loci are independently inherited from the st2 locus, soybean germplasm could be developed with more unique and useful combinations of these fatty acids. The objectives of this study were to combine the loci of high palmitic and stearic acids, and determine the effects of altered contents of palmitic and stearic acids on other fatty acids. HPKKJ10 was reciprocally crossed to M25. The data from F2 seed indicated that the fap2 and fapx loci controlling high palmitic acid were independently inherited from the st2 locus controlling high stearic acid. Thus, the germplasm (HPS) with the very high palmitic acid trait from HPKKJ10, and very high stearic acid trait from M25, was easily developed. The increases in palmitic acid due to the fap2 and fapx loci in HPKKJ10, and the increases in stearic acid due to the st2 locus in M25 were individually associated with changes in oleic acid. The combined increases in these two fatty acids in HPS were associated with decreases in oleic and linoleic acids, and increases in linolenic acid. The development of HPS with high content of saturated fatty acids could open new markets for soybean oil.

Soybean Oil: Genetic Approaches for Modification of Functionality and Total Content

“…In soybean, elevated stearic acid phenotype is governed by recessive loci manifested via mutagenesis (Rahman et al, 1995(Rahman et al, , 2003Spencer et al, 2003;Zhang et al, 2008), with one exception, genotype FAM94-41 (Pantalone et al, 2002). Homozygous lineages of soybean carrying the recessive elevated stearic acid alleles in soybean accumulate stearic acid in seed oil ranging from 19% to 30%, while the FAM94-41 genotype typically possesses 9% stearic acid.…”

GENETIC SOURCES REQUIRED FOR SOYBEAN BREEDING IN THE CONTEXT OF NEW BIOTECHNOLOGies (review)

“…The high-oleic variety does not differ from the control ones in total proteins, oil, hydrocarbons, coarse fiber, certain amino acids, vitamins, ashes, minerals, trypsin inhibitors, oligosugars [53]. By traditional selection, low palmitic acid lines were created [54,55]. In Japan, after chemical mutagenesis and x-ray treatment of seeds, lines with a high content of saturated fatty acids were revealed to increase the oil stability and to produce margarines and other solid and semi-solid fats.…”

Expression of the Arabidopsis WRINKLED 1 transcription factor leads to higher accumulation of palmitate in soybean seed

“…Similar efforts that combined the fad2‐1a , fad2‐1b , fad3a, and fad3c alleles produced a soybean oil high in oleate and low in linolenate close in fatty acid composition to that of olive oil (Pham et al ., ). Also, crossing high palmitic with high steric soybean lines produced an oil with a total of 38% saturates (Rahman et al ., ), whereas overexpression of a mangosteen FatA1, with the down‐regulation of FatB and FAD2 ‐1 led to soybeans seed oil with reduced palmitate and increased stearate, and oleate (Park et al ., ) similar to the sunflower oil profile obtained through conventional breeding (Perez‐Vich et al ., ). Our strategy for the assembly of genetic constructs linked to a single T‐DNA using the tools of biotechnology allowed for the reduction in copies of selectable markers, and helped minimize the duplication of genetic elements introduced into the soybean genome without compromising the phenotypes observed by crossing.…”