Breeding for Modified Fatty Acid Composition in Soybean

Abstract

ABSTRACT Genetic modification of the fatty acid composition of soybean [ Glycine max (L.) Merr.] oil has been successful in better meeting the needs of end users than is possible with conventional oil. Three modified oils are or have been sold commercially. Oil in which the linolenic acid (18:3) content has been reduced from 8 to 1% makes it possible to reduce or eliminate the need for chemical hydrogenation to achieve the stability and shelf life necessary for some food applications. Elimination of chemical hydrogenation and the trans‐ fatty acids produced by the process is important for human health. Oil in which the oleic acid (18:1) has been increased from 25 to >80% also have increased its stability and shelf life. An oil with palmitic acid (16:0) reduced from 11 to <4% makes it possible to achieve a low content of saturated fatty acids, which is desirable for cardiovascular health. The genetic changes in soybean oil were achieved by conventional breeding and genetic engineering. Mutagenesis was the conventional breeding method used to develop the major genes for reduced palmitic and linolenic acids that are in the cultivars currently grown for commercial production. Genetic engineering was used to elevate oleic acid to >80%. The purpose of this paper is to review the methods that have been used to develop the fatty acid modifications, the inheritance of the modifications, the impact of the trait on agronomic and seed characteristics, the methods of phenotypic and genotypic selection, and the commercial status of the modified oils.