Genome-Wide Association Study for Grain Micronutrient Concentrations in Wheat Advanced Lines Derived From Wild Emmer

Abstract

Wheat is one of the important staple crops as the resources of both food and micronutrient for most people of the world. However, the levels of micronutrients (especially Fe and Zn) in common wheat are inherently low. Biofortification is an effective way to increase the micronutrient concentration of wheat. Wild emmer wheat (Triticum turgidum ssp. dicoccoides, AABB, 2n = 4x = 28) is an important germplasm resource for wheat micronutrients improvement. In the present study, a genome-wide association study (GWAS) was performed to characterize grain iron, zinc, and manganese concentration (GFeC, GZnC, and GMnC) in 161 advanced lines derived from wild emmer. Using both the general linear model and mixed linear model, we identified 14 high-confidence significant marker-trait associations (MTAs) that were associated with GFeC, GZnC, and GMnC of which nine MTAs were novel. Six MTAs distributed on chromosomes 3B, 4A, 4B, 5A, and 7B were significantly associated with GFeC. Three MTAs on 1A and 2A were significantly associated with GZnC and five MTAs on 1B were significantly associated with GMnC. These MTAs show no negative effects on thousand kernel weight (TKW), implying the potential value for simultaneous improvement of micronutrient concentrations and TKW in breeding. Meanwhile, the GFeC, GZnC and GMnC are positively correlated, suggesting that these traits could be simultaneously improved. Genotypes containing high-confidence MTAs and 61 top genotypes with a higher concentration of grain micronutrients were recommended for wheat biofortification breeding. A total of 38 candidate genes related to micronutrient concentrations were identified. These candidates can be classified into four main groups: enzymes, transporter proteins, MYB transcription factor, and plant defense responses proteins. The MTAs and associated candidate genes provide essential information for wheat biofortification breeding through marker-assisted selection (MAS).

Introducing Beneficial Alleles from Plant Genetic Resources into the Wheat Germplasm

“…The results indicated that wild emmer is an important genetic resource for improving grain quality and increasing the contents of mineral nutrients in modern cultivated wheats [253]. Compared with cultivated wheat, wild emmer wheat accumulates higher contents of iron and zinc [85,254], as do T. boeoticum and T. monococcum [255,256]. Among Aegilops species, Ae.…”

Nutritional Properties of Larval Epidermis and Meat of the Edible Insect Clanis bilineata tsingtauica (Lepidoptera: Sphingidae)

“…Minerals are essential micronutrients for animals and humans [ 59 ]. In this study, we measured the concentrations of eight minerals in C. bilineata tsingtauica and found that Zn is the highest in C. bilineata tsingtauica meat and Fe is highest in the epidermis.…”

Did Wheat Breeding Simultaneously Alter Grain Concentrations of Macro- and Micro-Nutrient Over the Past 80 Years of Cultivar Releasing in China?

“…In addition, it is reported that grain macronutrient concentrations (e.g., N and P) have been declined over the breeding period ( Calderini et al, 1995 ; Calderini and Ortiz-Monasterio, 2003 ). However, results from other studies showed that grain concentration of mineral nutrient in wheat may not always be negatively correlated with grain yield or kernel weight, and produced either no clear trend or even a trend toward slight increase throughout the history of breeding ( Graham et al, 1999 ; Chen et al, 2017 ; Liu et al, 2021 ). The inconsistency among these results may be related to grain a yield level.…”

“…It has been widely recognized that biofortification strategy should focus on the staple food crops, such as wheat ( Triticum aestivum L.), which is a staple food for over 35% of the world’s population, and provides 20% of daily dietary protein, 21% of calories, and 14% of Cu, 11% of Zn, 13% of magnesium (Mg), and 15% of Fe ( Fan et al, 2008 ; Li et al, 2022 ). Wheat was found to contain relatively lower concentration of essential micronutrients (e.g., Fe, Zn, Cu, and Mn) in the grain ( Balint et al, 2001 ; Liu et al, 2021 ). Therefore, increasing grain mineral nutrient concentration in wheat is considered as a promising strategy to diminish human micronutrient malnutrition around the world.…”