Wheat Fructans: A Potential Breeding Target for Nutritionally Improved, Climate‐Resilient Varieties

Abstract

Wheat (Triticum aestivum L.) is a widely consumed staple crop and essential component of a healthy whole‐grain diet. One component of wheat, fructans, is known to serve physiological roles in the plant and confer health benefits to humans. Fructans serve as reserve carbohydrates and osmotic regulators against stresses (i.e., drought, cold temperatures, and salinity) that affect grain yield in the wheat plant. For humans, fructans are prebiotics that promote growth of healthy gut bacteria, aid in immune support, reduce colon cancer incidence, and support bone health. While cereals are the main source of fructans in the American diet, fructans are found in many other plant foods. Variation in wheat grain fructan content has been observed with several widely accepted fructan quantification techniques. Given the observed variation in grain fructan content and potential physiological benefits of fructans for wheat plants and consumers, fructans are a potential breeding target for developing climate‐resilient, nutritionally improved wheat varieties.

Influence of Genotype and Environment on Wheat Grain Fructan Content

“…If the trait is controlled by relatively few large-effect quantitative trait loci (QTL), marker-assisted selection (MAS) can be used to select for plants with those superior QTL alleles in the greenhouse, mitigating the need for extensive fructan phenotyping. Marker-based selection strategies will be key to reducing the extensive costs and labor of phenotyping of fructans in wheat grain (as proposed in Veenstra et al, 2017). Briefly, GS is used to first assign individuals a genomic estimated breeding value (GEBV) based on the sum of their predicted allele effects for all genome-wide loci, and then those individuals with the highest predicted breeding values are intermated to form the next generation (Meuwissen et al, 2001;Heffner et al, 2009).…”

“…For winter wheat, up to two cycles of selection can be completed in the greenhouse in a single year, increasing the rate of genetic gain while reducing the labor-intensive and expensive phenotyping of fructans in the field (Veenstra et al, 2017). For winter wheat, up to two cycles of selection can be completed in the greenhouse in a single year, increasing the rate of genetic gain while reducing the labor-intensive and expensive phenotyping of fructans in the field (Veenstra et al, 2017).…”

“…The key to GS is that once an appropriate model for allele effects has been determined, individuals need only be genotyped for selections to be made in subsequent generations. Marker-based selection strategies will be key to reducing the extensive costs and labor of phenotyping of fructans in wheat grain (as proposed in Veenstra et al, 2017). Although MAS and GS methods can be adapted to accommodate QTL ´ environment interactions that result in G´E, their use is complicated by the need to determine those QTL ´ environment effects and extrapolate those estimates to unobserved environments (Heslot et al, 2014).…”

“…The estimated genomic prediction accuracy of 0.52 for predicting GEBVs with the additive genetic model suggests that GS is feasible for wheat grain fructan content. For winter wheat, up to two cycles of selection can be completed in the greenhouse in a single year, increasing the rate of genetic gain while reducing the labor-intensive and expensive phenotyping of fructans in the field (Veenstra et al, 2017).…”

Recurrent genomic selection for wheat grain fructans

“…Fructan content within wheat grains averages between 1.28 and 1.40 g 100 g −1 (Andersson et al., 2013; Fretzdorff & Welge, 2003) with known variation between 0.7 and 2.9 g 100 g −1 (Huynh, Palmer, & Mather, 2008). The important physiological roles of fructans and known variation allow them to be a desirable breeding target for developing nutritionally improved, climate‐resilient wheat cultivars (Veenstra, Jannink, & Sorrells, 2017).…”