Changes in Lutein and Tocopherol Concentrations in Soybean Cultivars Released Across Seven Decades in the Short‐Season Region

Abstract

Lutein and α‐tocopherol (α‐toc) are antioxidant compounds beneficial for human health. Soybean [Glycine max (L). Merr.] contains relatively high concentrations of these compounds, and increasing them through plant breeding may be beneficial to human nutrition as well as provide a marketable seed trait in food‐type soybean. Our objective was to determine if there have been changes in lutein and tocopherol concentrations in short‐season soybean cultivars. A historical series of 16 cultivars released from 1934 to 2000 were grown at Ottawa Canada over a 3 yr period in a randomized complete‐block design with four replications. Seed was harvested for yield and a sample taken to determine seed weight, and oil, protein, lutein, α‐toc, γ‐tocopherol (γ‐toc), δ‐tocopherol (δ‐toc), and total‐tocopherol concentrations. There were significant differences among cultivars for all traits examined. Seed yield, oil, lutein, α‐toc, and δ‐toc concentrations have increased significantly since 1934, while protein concentration has decreased. There were no changes in seed weight and γ‐toc over time. Lutein and α‐toc were positively correlated with oil concentration and negatively correlated with protein concentration, leading to the conclusion that, over time, these compounds have likely increased in short‐season cultivars due to the indirect selection for higher oil concentration by plant breeders. The maximum concentration of lutein and α‐toc were similar to those found in other studies from different soybean growing regions indicating that only modest increases in these compounds may be possible using standard breeding techniques.

Temporospatial Characterization of Nutritional and Bioactive Components of Soybean Cultivars in China

“…The Satt376 and Satt266 markers have been reported to be significantly associated Table 3 Pearson correlation coefficients of the seed constituents of 89 widely grown soybean cultivars Table 1 with α-Toc content [41], indicating that these markers can be used in marker-assisted selection to facilitate the development of high-TE or α-Toc cultivars. In the short-season region of Canada, a series of 16 cultivars representing seven decades of cultivar release reflected significant increases in α-Toc and δ-Toc concentrations [6], which is consistent with our results. Given the positive correlation between oil and tocopherol content, the increase in tocopherol content in the present study may be ascribed to the indirect selection for high oil content by plant breeders over time.…”

“…Soybeans are the predominant source of plant protein and vegetable oil in the human diet [1]. In addition, soybeans contain health-beneficial phytochemicals, including lipidsoluble vitamins, mineral elements, oligosaccharides, saponins, phospholipids and isoflavones [2][3][4][5][6][7]. Among these, isoflavones, saponins, carotenoid and tocopherol have important functions in protecting against cancer, cardiovascular disease and oxidative deterioration [8][9][10][11].…”

“…These widely grown soybean cultivars have adapted to the environment and have excellent overall performance [15]. Changes in soybean lutein, tocopherol and isoflavone content with release date due to genetic breeding have been identified in previous research in the US [16], Canada [6,17] and China [18]. However, changes in the content of other soybean seed constituents, such as saponins, phospholipids, oligosaccharides and mineral elements, during the nearly 100 years of breeding have rarely been documented.…”

Temporal–Spatial Characterization of Seed Proteins and Oil in Widely Grown Soybean Cultivars across a Century of Breeding in China

“…With regards to the seed oil content, although it increased in the NH and HH regions, the pattern of change was not significant in the current study, suggesting that there is not genetic improvement in oil content across nine decades. This is inconsistent with the increasing trend in cultivars of the Midwestern United States (Wilcox et al, 1979) and the short‐season region of Canada (Morrison et al, 2015) and the first increasing and then decreasing trend in the mid‐southern US cultivars (Ustun et al, 2001). The relative stability in oil content and decrease in the protein content observed in this study may be attributable to two factors.…”

Temperature and precipitation at specific growth stages influence soybean tocopherol and lutein concentrations

“…AC Orford, Comet, and McCall) and three with contrasting lutein concentration (i.e. AC Bravor, Maple Glen, and Pagoda) were selected from a long‐term soybean cultivar evaluation experiment (Morrison et al., 2015). All cultivars were grown in a randomized complete block design with four replications.…”