title: Quantitative trait loci for whiteness of cooked rice detected in improved rice cultivars in Hokkaido.
abstract: Improving the eating quality of cooked rice has been one of the most important objectives in rice breeding programs. Eating quality of cooked rice is a complex trait including several components, such as external appearance, taste, aroma, and texture. Therefore, dissection of these components followed by marker-assisted selection of detected QTL(s) may be a useful approach for achieving desirable eating quality in rice breeding. Whiteness of cooked rice (WCR) is an important factor related to the external appearance of cooked rice. WCR is known to be associated with the amylose and protein contents of the endosperm. However, the genetic basis of WCR remains unclear. In this study, we evaluated phenotypic variation in WCR among recently developed rice cultivars from Hokkaido, Japan. Then, we developed doubled haploid lines (DHLs) derived from a cross between two cultivars from Hokkaido, Joiku No. 462 (high WCR) and Jokei06214 (low WCR). Using the DHLs, we detected two QTLs for WCR, qWCR3 and qWCR11, on chromosomes 3 and 11, respectively. We also examined the dosage effect of the two QTLs based on both the categorized segregants in the DHLs and the relationship between the WCR phenotype and inheritance around the QTL regions in cultivars from Hokkaido.
authors.affiliation: Rice Breeding Group, Kamikawa Agricultural Experiment Station, Local Independent Administrative Agency Hokkaido Research Organization , Minami 1-5, Pippu, Hokkaido 078-0397 , Japan.
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Shinada
authors.affiliation: Rice Applied Genomics Research Unit, National Institute of Agrobiological Sciences , Kannondai, Tsukuba, Ibaraki 305-8602 , Japan.
authors.forename: Toshio
authors.initials: T
authors.lastname: Yamamoto
authors.affiliation: Rice Applied Genomics Research Unit, National Institute of Agrobiological Sciences , Kannondai, Tsukuba, Ibaraki 305-8602 , Japan.
authors.forename: Eiji
authors.initials: E
authors.lastname: Yamamoto
authors.affiliation: Rice Applied Genomics Research Unit, National Institute of Agrobiological Sciences , Kannondai, Tsukuba, Ibaraki 305-8602 , Japan.
authors.forename: Kiyosumi
authors.initials: K
authors.lastname: Hori
authors.affiliation: Rice Breeding Group, Kamikawa Agricultural Experiment Station, Local Independent Administrative Agency Hokkaido Research Organization , Minami 1-5, Pippu, Hokkaido 078-0397 , Japan.
authors.forename: Yuji
authors.initials: Y
authors.lastname: Hirayama
authors.affiliation: Rice Breeding Group, Kamikawa Agricultural Experiment Station, Local Independent Administrative Agency Hokkaido Research Organization , Minami 1-5, Pippu, Hokkaido 078-0397 , Japan.
authors.forename: Toshihiko
authors.initials: T
authors.lastname: Maekawa
authors.affiliation: Rice Breeding Group, Kamikawa Agricultural Experiment Station, Local Independent Administrative Agency Hokkaido Research Organization , Minami 1-5, Pippu, Hokkaido 078-0397 , Japan.
authors.forename: Hitoshi
authors.initials: H
authors.lastname: Kiuchi
authors.affiliation: Rice Breeding Group, Kamikawa Agricultural Experiment Station, Local Independent Administrative Agency Hokkaido Research Organization , Minami 1-5, Pippu, Hokkaido 078-0397 , Japan.
authors.forename: Hirokazu
authors.initials: H
authors.lastname: Sato
authors.affiliation: Rice Breeding Group, Kamikawa Agricultural Experiment Station, Local Independent Administrative Agency Hokkaido Research Organization , Minami 1-5, Pippu, Hokkaido 078-0397 , Japan.
authors.forename: Takashi
authors.initials: T
authors.lastname: Sato
keywords: Oryza sativa L.; eating quality; rice breeding programs; whiteness of cooked rice