Yearly Variation of Isoflavone Composition and Yield-Related Traits of 35 Korean Soybean Germplasm

Abstract

In this study, composition and agronomic traits, including yield-related traits, were investigated and compared among 35 Korean landrace germplasm for two years (2019 and 2020). The contents of 12 isoflavones were measured using high-performance liquid chromatography, and agronomic trait data were collected according to the Rural Development Administration criteria. Comparing isoflavone composition between the two years, all isoflavones, except glycitein, were generally higher in 2019. The values of yield-related and major agronomic traits decreased in most accessions in 2020. ANOVA showed highly significant differences (p<0.001) in genotypes, years, and genotype-by-year interaction for all isoflavones, the number of pods per plant, and 100-seed weight. The number of seeds per pod, days to flowering, and days to maturity also showed significant differences among genotypes, as well as between the two years. Correlation analysis revealed that daidzin and genistin were positively correlated with their malonylated form. Malonyl daidzin was also positively correlated with malonyl genistin levels. The accessions with the least variation in the total isoflavone content were IT 153844 (907.5 µg/g, 898.6 µg/g) and IT 252252 (663.2 µg/g, 636.4 µg/g). Some of the evaluated landraces will be a promising genetic source for developing soybean varieties with high levels of environmental stability in isoflavone content and agronomic traits.

Genome wide association study to detect genetic regions related to isoflavone content in a mutant soybean population derived from radiation breeding

“…We detected weaker positive correlations between total isoflavones and aglycones [DZE, GLE, and GNE (r = 0.46-0.82 in 2020 and r = 0.12-0.20 in 2021)]; and between total isoflavones and acetyl glucosides [ADZI and AGNI (r = 0.26-0.96 in 2020 and r = 0.47-0.95 in 2021)]. Across both years, DZI (r = 0.93 * * * , r = 0.89 * * * ), GNI (r = 0.94 * * * , r = 0.89 * * * ), MDZI (r = 0.94 * * * , r = 0.94 * * * ), MGNI (r = 0.94 * * * , r = 0.96 * * * ) and ADZI (r = 0.95 * * * , r = 0.96 * * * ) showed significantly strong positive correlations with TI and with each other, consistent with the results of other studies (Azam et al, 2020;Yoon et al, 2021).…”

What Is the Relationship between Antioxidant Efficacy, Functional Composition, and Genetic Characteristics in Comparing Soybean Resources by Year?

“…Some studies have reported that the anthocyanin-based component of the seed coat color contributes to increasing the antioxidant activity of the soybeans and that the antioxidant activity decreases as the color of the seed coat of soybeans becomes lighter [ 43 , 44 ]. The samples that maintained the highest activity in both the first and second years were B17, B15, and B23 in the black group, revealing that the traits remained stable in these samples despite climatic variations [ 22 ].…”

“…The sum of the duration of daylight from June to September was 620.7 h in the normal year, whereas it amounted to 672.5 h in 2019, which was 51.8 h longer than in the normal year. The sum was 585.3 h in 2020, which was 35.4 h shorter than the normal year [ 22 ]. The decrease in the duration of daylight would have had the same effect as the shade stress, resulting in increased antioxidant components and efficacy due to the increase in anthocyanins.…”

“…This powder was utilized as an analysis sample [ 5 ]. Based on the Jeonju climate statistics data of the Korea Meteorological Administration, this study calculated the normal based on the meteorological environment during the cultivation period and the last 30 years (1991–2020) to create the data for investigation [ 22 ]. A total of 48 resources were classified by seed coat color into 19 types of yellow varieties (Y1–Y19), 25 types of black varieties (B1–B25), 4 types of green-black varieties (G1–G4), with 1 yellow (C1) and 1 black (C2) variety as control varieties ( Table 1 ) [ 10 ].…”

“…In addition, research has extended to soybean varieties to obtain a stable isoflavone content, suggesting that repeated evaluation in various growing environments is essential for selecting soybean varieties [ 21 ]. To this end, Yoon et al [ 22 ] conducted an annual comparison of the isoflavone content, quantity-related traits (number of pods per plant and number of seeds per pod), and major agricultural traits (number of days to flowering and maturation) of Korean native soybean genetic resources to select a genetic resource with little annual variation in its isoflavone content and quantity-related traits.…”