Submitted to: Cereal Chemistry
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 9/8/2011
Publication Date: 12/14/2011
Publication URL: http://naldc.nal.usda.gov.d2.nal.usda.gov/download/53946/PDF
Citation: Morris, C.F., Anderson, J.A., King, G.E., Bettge, A.D., Garland Campbell, K.A., Fuerst, E.P., Beecher, B.S. 2011. On the occurrence of a unique 'super soft' kernel trait in wheat. Cereal Chemistry. 88:576-583. Interpretive Summary: Wheat hardness is one of the major factors influencing wheat breeding, marketing and use. In the U.S., Australia and Canada, marketing and breeding is limited to two discrete soft and hard wheat classes, based on the puroindoline genes. However, within the soft wheat class kernel texture variation exists. The reason that kernel texture is important has to do with the material properties of the kernel when it is milled into flour. In this sense, flour milling performance and flour quality provide the most appropriate metrics of kernel texture. In summary, we have identified a highly novel soft kernel trait in wheat. The trait is primarily manifested in reduced SKCS kernel texture and higher break flour yields, with some increase in SRC carbonate values and sponge cake volumes. With the possible exception of the SRC carbonate values, we observed no indication that the super soft trait conferred any negative aspects of soft wheat quality. The super soft trait was always equal to or better than its normal soft siblings. This trait may provide wheat breeders new opportunities to modify end-use quality of wheat.
Technical Abstract: Kernel texture in wheat (Triticum sp. L.) is central to end-use quality and utilization. This report documents the discovery of a novel soft kernel trait in wheat (T. aestivum). Soft white winter wheat lines that carried the novel trait were identified among 882 F3-derived breeding lines. Nine sister lines of the pedigree ‘WA7437’/‘WA7665’ were advanced through several generations of selfing with no selection as part of the USDA ARS cultivar development program. Subsequently, individual plants were selected and propagated as inbred sibs. Lastly, replicated multi-location field plots were grown to evaluate the grain, milling, flour quality and end-product (cookie and cake) quality. Two heritable kernel phenotypes were consistently observed. To delineate these two soft wheat kernel phenotypes, the monikers of ‘normal’ soft and ‘super’ soft were applied. Normal soft lines exhibited Single Kernel Characterization System (SKCS) values typical of Pacific Northwest soft wheat (e.g. 20) whereas the super soft lines from the same environments produced SKCS values of 4.6. Under some environments, individual super soft lines exhibited SKCS kernel texture values as low as -4. The super soft trait is primarily manifested in reduced SKCS kernel texture (15 less than normal soft sibs, 30 less than cv. ‘Madsen’), and higher break flour yields (2.5% more than normal soft sibs, 6.7% more than Madsen), with some increase in SRC carbonate values and sponge cake volumes. Straight-grade flour yield, flour ash and milling score were largely unaffected. With the possible exception of the SRC carbonate values, we observed no indication that the super soft trait conferred any “negative” aspects of soft wheat quality. As such, this trait may provide wheat breeders new opportunities to modify end-use quality of wheat.