Selection for soyabeans with high and environmentally stable lutein concentrations

Abstract

Lutein has significant nutritional benefits for human health. Therefore, enhancing soybean lutein concentrations is an important breeding objective. However, selection for soybeans with high and environmentally stable lutein concentrations has been limited. The objectives of this study were to select soybeans with high seed lutein concentrations and to determine the stability of lutein concentrations across environments. A total of 314 genotypes were screened and 18 genotypes with high lutein concentrations and five genotypes with low lutein concentrations were selected for further examination. These 23 genotypes and two check varieties were evaluated under six environments (two planting dates for 2 years at one location and two planting dates for 1 year at another location). Lutein concentrations were influenced by genotype, environment and genotype £ environment interactions. Genotypes with late maturity and low lutein concentrations were more stable than those with early maturity and high concentrations. Early (May) planting resulted in greater lutein concentrations than late (June) planting. Among the genotypes evaluated, PI603423B (7.7 mg/g) and PI89772 (5.8 mg/g) had the greatest mean lutein concentrations and exhibited medium and high stability across the six environments, respectively. Thus, these genotypes may be useful for breeding soybeans with high and stable seed lutein concentrations.

Seed Carotenoid and Tocochromanol Composition of Wild Fabaceae Species Is Shaped by Phylogeny and Ecological Factors

“…One of the few studies on the seeds of wild plant species revealed that grain legumes have lower contents of carotenoids (including those of nutritional value for human and livestock feeding, such as L and Z) than their wild counterparts, indicating a decrease in the concentration of carotenoids in seeds in the course of domestication ( Fernández-Marín et al, 2014 ). These data are further supported by recent studies on seed carotenoids in the economically most important pulses: soybean, pea, chickpea, and lentil, of which the seeds of most crop genotypes contained lower total carotenoid levels than those of their wild relatives ( Zhang et al, 2014 ; Dhakal et al, 2014 ; Ashokkumar et al, 2015 ). As suggested in Fernández-Marín et al (2014) the loss of carotenoids during domestication likely occurred as a side-effect of the selection for other desired traits such as the loss of seed dormancy and dispersal mechanisms, and selection for seed storability and taste.…”