Wang Ming Li, Khera Pawan, Pandey Manish K, Wang Hui, Qiao Lixian, Feng Suping, Tonnis Brandon, Barkley Noelle A, Pinnow David, Holbrook Corley C, Culbreath Albert K, Varshney Rajeev K, Guo Baozhu
Plant Genetics Resources Conservation Unit, US Department of Agriculture-Agricultural Research Service, Griffin, Georgia, United States of America.
Crop Protection and Management Research Unit, US Department of Agriculture-Agricultural Research Service, Tifton, Georgia, United States of America; International Crops Research Institute for the Semi-Arid Tropics (ICRISAT), Hyderabad, Telangana, India; Department of Plant Pathology, University of Georgia, Tifton, Georgia, United States of America.
PLoS One. 2015 Apr 7;10(4):e0119454. doi: 10.1371/journal.pone.0119454. eCollection 2015.
Peanut, a high-oil crop with about 50% oil content, is either crushed for oil or used as edible products. Fatty acid composition determines the oil quality which has high relevance to consumer health, flavor, and shelf life of commercial products. In addition to the major fatty acids, oleic acid (C18:1) and linoleic acid (C18:2) accounting for about 80% of peanut oil, the six other fatty acids namely palmitic acid (C16:0), stearic acid (C18:0), arachidic acid (C20:0), gadoleic acid (C20:1), behenic acid (C22:0), and lignoceric acid (C24:0) are accounted for the rest 20%. To determine the genetic basis and to improve further understanding on effect of FAD2 genes on these fatty acids, two recombinant inbred line (RIL) populations namely S-population (high oleic line 'SunOleic 97R' × low oleic line 'NC94022') and T-population (normal oleic line 'Tifrunner' × low oleic line 'GT-C20') were developed. Genetic maps with 206 and 378 marker loci for the S- and the T-population, respectively were used for quantitative trait locus (QTL) analysis. As a result, a total of 164 main-effect (M-QTLs) and 27 epistatic (E-QTLs) QTLs associated with the minor fatty acids were identified with 0.16% to 40.56% phenotypic variation explained (PVE). Thirty four major QTLs (>10% of PVE) mapped on five linkage groups and 28 clusters containing more than three QTLs were also identified. These results suggest that the major QTLs with large additive effects would play an important role in controlling composition of these minor fatty acids in addition to the oleic and linoleic acids in peanut oil. The interrelationship among these fatty acids should be considered while breeding for improved peanut genotypes with good oil quality and desired fatty acid composition.
花生是一种含油量约为50%的高油作物，要么被压榨取油，要么用作食用产品。脂肪酸组成决定了油脂品质，而油脂品质与消费者健康、风味以及商业产品的保质期密切相关。除了占花生油约80%的主要脂肪酸油酸（C18:1）和亚油酸（C18:2）外，其他六种脂肪酸，即棕榈酸（C16:0）、硬脂酸（C18:0）、花生酸（C20:0）、二十碳烯酸（C20:1）、山嵛酸（C22:0）和木蜡酸（C24:0）占其余的20%。为了确定遗传基础并进一步加深对FAD2基因对这些脂肪酸影响的理解，构建了两个重组自交系（RIL）群体，即S群体（高油酸品系‘SunOleic 97R’×低油酸品系‘NC94022’）和T群体（普通油酸品系‘Tifrunner’×低油酸品系‘GT-C20’）。分别利用包含206个和378个标记位点的S群体和T群体的遗传图谱进行数量性状位点（QTL）分析。结果，共鉴定出164个与次要脂肪酸相关的主效（M-QTLs）和27个上位性（E-QTLs）QTL，表型变异解释率（PVE）为0.16%至40.56%。还鉴定出34个主要QTL（>10%的PVE）定位在五个连锁群上，以及28个包含三个以上QTL的簇。这些结果表明，除了花生油中的油酸和亚油酸外，具有大的加性效应的主要QTL在控制这些次要脂肪酸的组成方面将发挥重要作用。在培育具有良好油脂品质和理想脂肪酸组成的花生优良基因型时，应考虑这些脂肪酸之间的相互关系。
