Puroindoline genes introduced into durum wheat reduce milling energy and change milling behavior similar to soft common wheats

Authors: HEINZE, K - Institut National De La Recherche Agronomique (INRA); Kiszonas, Alecia; MURRAY, JESSICA - Washington State University; Morris, Craig; LULLIEN-PELLERIN, VALERIE - Institut National De La Recherche Agronomique (INRA)

Submitted to: Journal of Cereal Science
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 8/28/2016
Publication Date: 9/6/2016
Publication URL: https://handle.nal.usda.gov/10113/5491335
Citation: Heinze, K., Kiszonas, A., Murray, J.C., Morris, C.F., Lullien-Pellerin, V. 2016. Puroindoline genes introduced into durum wheat reduce milling energy and change milling behavior similar to soft common wheats. Journal of Cereal Science. 71:183-189.

Interpretive Summary: Wheat grain hardness is a key parameter that influences its mechanical properties, milling behavior, and end-uses. Grain hardness was found mainly related to the genetic background and more precisely to the Hardness locus, Ha, on the short arm of chromosome 5D, which encodes the so-called Puroindolines a and b. Recently, both of the wild-type alleles of the puroindoline genes were successfully introduced in a durum wheat background opening the way to obtain wheat grains with expected changes in their milling behavior and product properties in comparison with the durum parent cultivar. The present study analyzes in detail the grain characteristics and milling behavior and required energy to grind of a recombinant Italian durum cultivar, Svevo in which puroindoline genes were introduced (“Svevo-Pin”) in comparison with the parent cultivar grown together in distinct locations. Some highlights of this manuscript are: - Wild-type puroindolines introduced in durum wheat reduces the grain grinding energy - Flour yield, particle size and tissue distribution were also modified - Starch damage reduction was observed in puroindoline transformed durum wheat grains - Differences in milling behavior were observed whatever the environmental conditions

Technical Abstract: Grain physical characteristics and milling behavior of a durum wheat line in which both wild-type puroindoline alleles were translocated and stabilized after backcrossing (Svevo-Pin) were compared with the parent line (Svevo). The only observed differences between grain characteristics were the mechanical resistance and starchy endosperm porosity revealed through vitreosity measurement. A significant increase of flour and a decrease of semolina yield and break milling energy were observed from Svevo-Pin in comparison with the non-recombinant parent line in accordance to the lower grain mechanical resistance and higher porosity measurements. Moreover, the particle size distribution shown for Svevo-Pin flour appeared coherent with a lower adhesion between starch granules and the protein matrix attributed to the presence of wild-type puroindolines. Coarse bran yield was conversely increased due to puroindolines presence. This appeared to be due to a lower starchy endosperm recovery as higher proportion of grain starch was found in this bran fraction. Flour from the durum parent line was inversely enriched in phytic acid, a cellular marker of the aleurone layer. Starch damage was also lower in Svevo-Pin flours in comparison with Svevo. All of the observed differences between transformed and parent line were confirmed whatever the culture growth conditions (n=12).