title: Identification of a stable quantitative trait locus for percentage grains with white chalkiness in rice (Oryza sativa).
abstract: High chalkiness is a major problem in many rice-producing areas of the world, especially in hybrid rice (Oryza sativa L.) in China. We previously showed a major quantitative trait locus for the percentage of grains with white chalkiness (QTLqPGWC-8) in the interval G1149-R727 on chromosome 8 using a chromosome segment substitution line (CSSL). Here, we selected the line-CSSL50 harboring the QTLqPGWC-8 allele from the CSSLs derived from a cross between Asominori (as a recurrent parent) and IR24 (as a donor parent), which had higher percentage chalkiness, markedly different from that of Asominori. There were also significant differences in starch granules, appearance of amylose content (AAC) and milling qualities between Asominori and CSSL50, but not in grain size or thousand grain weight (TGW). The BC(4) F(2) and BC(4) F(3) populations from a cross between CSSL50 and Asominori were used for fine mapping of qPGWC-8. We narrowed down the location of this QTL to a 142 kb region between Indel markers 8G-7 and 8G-9. QTLqPGWC-8 accounted for 50.9% of the difference in PGWC between the parents. The markers tightly linked to qPGWC-8 should facilitate cloning of the gene underlying this QTL and will be of value for marker-assisted selection in breeding rice varieties with better grain quality.
authors.affiliation: Key Laboratory of Crop Genetics and Germplasm Enhancement/Jiangsu Plant Gene Engineering Research Center, Nanjing Agricultural University, China.
authors.forename: Tao
authors.initials: T
authors.lastname: Guo
authors.forename: Xiaolu
authors.initials: X
authors.lastname: Liu
authors.forename: Xiangyuan
authors.initials: X
authors.lastname: Wan
authors.forename: Jianfeng
authors.initials: J
authors.lastname: Weng
authors.forename: Shijia
authors.initials: S
authors.lastname: Liu
authors.forename: Xi
authors.initials: X
authors.lastname: Liu
authors.forename: Mingjiang
authors.initials: M
authors.lastname: Chen
authors.forename: Jingjing
authors.initials: J
authors.lastname: Li
authors.forename: Ning
authors.initials: N
authors.lastname: Su
authors.forename: Fuqing
authors.initials: F
authors.lastname: Wu
authors.forename: Zhijun
authors.initials: Z
authors.lastname: Cheng
authors.forename: Xiuping
authors.initials: X
authors.lastname: Guo
authors.forename: Cailin
authors.initials: C
authors.lastname: Lei
authors.forename: Jiulin
authors.initials: J
authors.lastname: Wang
authors.forename: Ling
authors.initials: L
authors.lastname: Jiang
authors.forename: Jianmin
authors.initials: J
authors.lastname: Wan
mesh_terms: D000688:Amylose / Q000378:metabolism; D001483:Base Sequence; D018533:Biomass; D002874:Chromosome Mapping; D005838:Genotype; D018895:Microsatellite Repeats / Q000235:genetics; D008969:Molecular Sequence Data; D012275:Oryza / Q000235:genetics* / Q000648:ultrastructure; D010641:Phenotype; D040641:Quantitative Trait Loci / Q000235:genetics*; D019655:Quantitative Trait, Heritable; D012639:Seeds / Q000235:genetics* / Q000648:ultrastructure; D013213:Starch / Q000378:metabolism
chemical_list: D013213:Starch; D000688:Amylose