Inheritance of Reduced Linolenic Acid Content in Soybean Genotypes A16 and A17

Abstract

Reduction of linolenic acid content in soybean [Glycine max (L.) Merr.] oil is associated with improved odor and flavor characteristics. Germplasm with the lowest content of this fatty acid known in soybean (<25 g kg−1) was identified in 1986 at Iowa State University from the cross of two mutant lines, A5 × A23. The objective of our study was to determine the genetic control of the reduced linolenic acid content in two lines from that cross, AI6 and AfT. The two lines with < 25 g kg−1 linolenic acid were mated reciprocally to ‘Century 84’ (77 g kg−1 linolenic), the mutant line C1640 (37 kg−1 li nolenic) an d the parents, A5 and A23. There was no maternal effect when AI6 and AI7 were crossed to their parents, but a partial maternal effect was observed in crosses with Century 84 and C1640. In the crosses of Al6 and AI7 with Century 84, the segregation of the F2.3 lines satisfactorily fit a 1:14:1 ratio, which would be expected with the segregation of major genes at two independent loci. The data indicated that AI6 and AI7 obtained the fan(A5) allele from A5 and the fan2(A23) allele from A23. The continuous distributions observed in the AI6 and AI7 crosses with Century 84 indicated that minor genes and environmental effects also are important in the expression of linolenic acid content. Consequently, the low linolenic acid content of AI6 and AI7 can be considered a quantitative character for cultivar development programs.

Biometrical analyses of linolenic acid content of soybean seeds

“…The linolenic acid content showed high heritability, which is in agreement with the results obtained by Fehr et al (1992). As a general rule, traits defined by a small number of genes show high heritabilities in early generations, permitting the fixation of distinct genotypes by using a small number of selfing generations (Anand and Torrie, 1963).…”

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

“…A number of low linolenic acid soybean oil (low-lin) genotypes have been developed through mutational breeding (Hammond and Fehr, 1983a;Wilcox and Cavins, 1985;Fehr et al, 1992). Low-lin soybean oil typically has linolenic acid percentages below 4%, with ultra-lowlin under 2%.…”

Relationships and inheritance of linolenic acid and seed lipoxygenases in soybean crosses designed to combine these traits

“…Low LA content in line C1640 was found to be controlled by a single recessive fan(C1640) allele at a major Fan locus (Wilcox and Cavins 1985). Different patterns of inheritance for LA have been observed including quantitative inheritance (Graef et al 1988) or a combination of major and minor genes (Fehr et al 1992). The low linolenic acid (LLA) content in RG10 and PI 361088B is simply inherited and controlled by homozygous recessive alleles with additive effects at the Fan locus (Rennie et al 1988;Stojsin et al 1998).…”