Effect of wheat (Triticum aestivum L.) seed color and hardness genes on the consumption preference of the house mouse (Mus musculus L.)

Authors: Kiszonas, Alecia; FUERST, E - Washington State University; TALBERT, L - Montana State University; SHERMAN, C - Montana State University; Morris, Craig

Submitted to: Mammalia
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 11/19/2015
Publication Date: 10/19/2016
Publication URL: https://handle.nal.usda.gov/10113/63284
Citation: Kiszonas, A., Fuerst, E.P., Talbert, L., Sherman, C.F., Morris, C.F. 2016. Effect of wheat (Triticum aestivum L.) seed color and hardness genes on the consumption preference of the house mouse (Mus musculus L.). Mammalia. 80:655-662.

Interpretive Summary: The house mouse evolved as a commensal with human sedentary agriculture, and although omnivorous by nature, it is highly adapted to consuming crop seeds, especially wheat (Triticum aestivum L). In previous wheat grain feeding studies, mouse consumption preference was observed to be highly biased towards white as opposed to red bran color, and soft grain texture. In feeding trials involving a larger set of wheat varieties it was shown that the number of red color genes and relatively small differences in grain texture were not the primary factors determining seed selection and consumption, implying that other selection criterion was involved. In this study we used highly genetically similar wheat near-isogenic lines to study the role that grain (bran) color/pigmentation and texture (hardness) genes have on the consumption preference of C57BL/6J mice.Given the results of this research, our understanding of color and hardness is more complex than had been previously imagined. The preference for one color or the other does not have the simple binary response expected. Nor is hardness a matter of increasing preference with increasing kernel softness. Clearly kernel hardness is a more straightforward, albeit very fine and exact discrimination in mouse feeding preference, whereas color is a more complex and nuanced system in flavor and feeding preference.

Technical Abstract: Background: Wheat (Triticum aestivum L.) grain is a staple food and provides necessary nutrients for human health and nutrition. Yet, flavor differences among wheat varieties are not well understood. Grain flavor and consumption preference can be examined using the house mouse (Mus musculus L.) as a model system. Prior research has shown that mice prefer white colored bran wheat kernels. Red kernels, which may have a more bitter flavor, are less desirable to mice. Objective: The present study examined the wheat grain consumption preference of C57BL/6J inbred mice relative to the number of Red color genes, and varied kernel hardness within sets of near-isogenic lines. Methods: The number of Red color genes varied from 0 to 3 in two different hard red spring wheat genetic backgrounds, Choteau and Vida. Differences in kernel hardness varied due to Puroindoline genes within a set of Alpowa white spring wheat near-isogenic lines. All tests used binary mixtures of grain. Results: Consumption discrimination of wheat kernels based on color was somewhat more complex than has been previously described, nevertheless, lines with more Red genes was never preferred over lines with fewer Red genes. When using near-isogenic lines to remove flavor/aroma differences, grain consumption was influenced by small differences in kernel texture with the softer kernel line in each of six variety pairings consistently preferable. Conclusion: The model system clearly identified that fewer compared to a greater number of red bran color genes (and pigmentation) was preferred by mice. Pigment-related compounds may confer undesirable taste or aroma. When all other grain traits are genetically controlled, mice are sensitive to texture, preferring softer kernels. The mouse model system can advance grain-related nutrition research.