Genotyping High-oleic Soybean Segregants using Fatty Acid Linked Markers

Background: Improving oil quality is an important mandate in soybean breeding. Marker-assisted selection for the desired fatty acid composition is easier and technically convenient. Methods: In the present investigation, 110 segregants from parents with contrasting oleic acid content were screened using candidate markers of Omega-6 fatty acid desaturase 2-1 (Fad2-1A and Fad2-1B) genes and linked with QTLs for oleic acid content. Result: Out of the 10 molecular markers studied, 7 were found polymorphic (IFAD2-1A, IFAD2-1B, Sat_108, Satt294, Satt386, Satt002, Satt001), while Satt354 behaved like a null allele. Among them, Satt386, Satt294 and Satt354 were most informative for screening individual segregants to reveal 38 (F2: 14, F3: 24); 42 (F2: 14, F3: 28) and 39 (F2: 3, F3: 36) segregants, respectively, with markers matching NRC 147, the higher oleate parent. Further, FAD2-1A/ FAD2-1B specific primers were developed from sequence analysis, which differentially amplified 401 bp and 378 bp markers simultaneously for those two isoforms. The identified markers may potentially contribute to breeding favorable soybean oil characteristics.