title: Improvement of Rice Biomass Yield through QTL-Based Selection.
abstract: Biomass yield of rice (Oryza sativa L.) is an important breeding target, yet it is not easy to improve because the trait is complex and phenotyping is laborious. Using progeny derived from a cross between two high-yielding Japanese cultivars, we evaluated whether quantitative trait locus (QTL)-based selection can improve biomass yield. As a measure of biomass yield, we used plant weight (aboveground parts only), which included grain weight and stem and leaf weight. We measured these and related traits in recombinant inbred lines. Phenotypic values for these traits showed a continuous distribution with transgressive segregation, suggesting that selection can affect plant weight in the progeny. Four significant QTLs were mapped for plant weight, three for grain weight, and five for stem and leaf weight (at α = 0.05); some of them overlapped. Multiple regression analysis showed that about 43% of the phenotypic variance of plant weight was significantly explained (P < 0.0001) by six of the QTLs. From F2 plants derived from the same parental cross as the recombinant inbred lines, we divergently selected lines that carried alleles with positive or negative additive effects at these QTLs, and performed successive selfing. In the resulting F6 lines and parents, plant weight significantly differed among the genotypes (at α = 0.05). These results demonstrate that QTL-based selection is effective in improving rice biomass yield.
authors.affiliation: NARO Institute of Crop Science, Tsukuba, Ibaraki 305-8518, Japan.
authors.forename: Kazuki
authors.initials: K
authors.lastname: Matsubara
authors.affiliation: National Institute of Agrobiological Sciences, Tsukuba, Ibaraki 305-8602, Japan.
authors.forename: Eiji
authors.initials: E
authors.lastname: Yamamoto
authors.affiliation: NARO Institute of Crop Science, Tsukuba, Ibaraki 305-8518, Japan.
authors.forename: Nobuya
authors.initials: N
authors.lastname: Kobayashi
authors.affiliation: NARO Institute of Crop Science, Tsukuba, Ibaraki 305-8518, Japan.
authors.forename: Takuro
authors.initials: T
authors.lastname: Ishii
authors.affiliation: NARO Institute of Crop Science, Tsukuba, Ibaraki 305-8518, Japan.
authors.forename: Junichi
authors.initials: J
authors.lastname: Tanaka
authors.affiliation: NARO Institute of Crop Science, Tsukuba, Ibaraki 305-8518, Japan.
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Tsunematsu
authors.affiliation: NARO Agricultural Research Center, Niigata 943-0154, Japan.
authors.forename: Satoshi
authors.initials: S
authors.lastname: Yoshinaga
authors.affiliation: NARO Agricultural Research Center, Niigata 943-0154, Japan.
authors.forename: Osamu
authors.initials: O
authors.lastname: Matsumura
authors.affiliation: National Institute of Agrobiological Sciences, Tsukuba, Ibaraki 305-8602, Japan.
authors.forename: Jun-Ichi
authors.initials: J
authors.lastname: Yonemaru
authors.affiliation: National Institute of Agrobiological Sciences, Tsukuba, Ibaraki 305-8602, Japan.
authors.forename: Ritsuko
authors.initials: R
authors.lastname: Mizobuchi
authors.affiliation: National Institute of Agrobiological Sciences, Tsukuba, Ibaraki 305-8602, Japan.
authors.forename: Toshio
authors.initials: T
authors.lastname: Yamamoto
authors.affiliation: NARO Institute of Crop Science, Tsukuba, Ibaraki 305-8518, Japan.
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Kato
authors.affiliation: NARO Institute of Crop Science, Tsukuba, Ibaraki 305-8518, Japan.
authors.forename: Masahiro
authors.initials: M
authors.lastname: Yano
mesh_terms: D000483:Alleles; D018533:Biomass; D032461:Chromosomes, Plant; D018556:Crops, Agricultural; D008040:Genetic Linkage; D012275:Oryza / Q000235:genetics*; D010641:Phenotype; D040641:Quantitative Trait Loci