Breeding of a hard and waxy wheat cultivar, “Mochiharuka”

Abstract

Waxy wheat was bred by the pedigree breeding method in Japan for the first time in the world. However, its usage is limited because a hard and waxy wheat cultivar was not developed. A hard wheat generally has the Glu-D1d gene, which strengthens the gluten. On the other hand, current Japanese waxy wheat cultivars do not have this gene, thus the gluten is weakened. When conventional waxy wheat flour is blended to improve the texture of bread, the strength of gluten in the dough is weakened as a result. Institute of Crop Science, NARO, and Kumamoto Flour Milling co., Ltd. worked together to breed a hard and waxy wheat cultivar, “Mochiharuka”, whose genetic background was the hard wheat cultivar “Yumeshiho”, using the methods of DNA marker selection, continuous backcross, near-isogenic lineage production, and generation promotion in greenhouses. Compared with “Yumeshiho”, the panicles are longer, volume weight and yield are slightly smaller, appearance quality is the same or slightly worse, pre-harvest sprouting is slightly difficult to difficult, and the degree of resistance to wheat yellow mosaic and leaf rust are slightly weak in “Mochiharuka”. The other agronomic traits are equivalent. “Mochiharuka” has little amylose in the endosperm starch and very high-water absorption on Farinogram. The maximum viscosity temperature on an amylogram is low. In a processing test using wheat flour blended with “Mochiharuka”, it was evaluated that the bread has a soft and chewy texture, ramen noodles have strong viscoelasticity, and gyoza-wrappers have a chewy texture. It is expected to lead to commercialization.