Thursday, November 16, 2006 - 10:00 AM

Confirmation of Soybean Fatty Acid Modifier QTL.

Catherine N. Nyinyi, Fred L. Allen, Dean A. Kopsell, Carl E. Sams, and Vincent R. Pantalone. University of Tennessee, 2431 Joe Johnson Dr., Dept. of Plant Sciences, 252 Ellington Bldg., Knoxville, TN 37996-4561

Producing soybeans which have specific fatty acid content is of prime importance for edible oil and industrial purposes. Several modifiers have been found to influence palmitic, stearic, oleic, linoleic and linolenic acid content. The purpose of this study is to confirm previously reported quantitative trait loci (QTL) for fatty acid modifier genes in an independent ‘Essex’ x ‘Williams 82’ population. Fatty acid analysis by gas chromatography of the methyl esters has been completed for 147 F5:6 recombinant inbred lines (RIL) and the two parents. The 147 RILs averaged 105.3 g Kg-1 palmitic acid, 45.6 g Kg-1 stearic acid, 247.8 g Kg-1 oleic acid, 528.6 g Kg-1 linoleic acid and 72.7 g Kg-1 linolenic acid. Parents have been screened with 42 SSR markers on linkage groups (LGs) C2, D1b, D2, F, K and L, previously linked to fatty acid modifier QTL. Polymorphisms were found between the parents for 28 of 42 SSR markers screened. RILs have been screened with the polymorphic SSR markers and single factor ANOVA used to identify QTL. Genomic regions where QTL were associated with fatty acid modifiers were: palmitic acid [Satt079 (LG C2), Satt372 (LG D2), Satt149 (LG F), Satt362 (LG F)], stearic acid [Satt274 (D1b)], oleic acid [Satt372 (LG D2), Satt725 (LG K), Satt076 (LG L), Satt166 (LG L), Satt481 (LG L), Satt527 (LG L) Satt561 (LG L)],  linoleic acid [Satt274 (LG D1b), Satt076 (LG L), Satt166 (LG L), Satt527 (LG L), Satt561 (LG L), linolenic acid [Satt252 (LG F), Satt348 (LG F), Satt725 (LG K), Satt076 (LG L), Satt481 (LG L), Satt527 (LG L), Satt561 (LG L)]. RILs have been grown in Knoxville, TN (2006) for data collection and seed increase. In 2007 the population will be grown in three locations for multi environment data analyses for the validation of QTL.