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Genetic mechanisms determining grain number distribution along the spike and their effect on yield components in wheat.

ABSTRACT: The number of wheat grains is one of the major determinants of yield. Many quantitative trait loci (QTLs) and some causal genes such as GNI-A1 and WAPO-A1 that are associated with grain number per spike (GNS) have been identified, but the underlying mechanisms remain largely unknown. We analyzed QTLs for grain number and other related traits using 188 doubled haploid lines derived from the Japanese high-yield variety, Kitahonami, as a parent to elucidate the genetic mechanism determining grain number. The major QTLs for grain number at the apical, central, and basal parts of the spike were identified in different chromosomal regions. We considered GNI-A1 and WAPO-A1 as candidate genes controlling grain number at the central and basal parts of the spike, respectively. Kitahonami had the favorable 105Y allele of GNI-A1 and WAPO-A1b allele and unfavorable alleles of QTLs for grain number at the apical part of spikes. Pyramiding the favorable alleles of these QTLs significantly increased GNS without significantly reducing thousand-grain weight (TGW). In contrast, the accumulation of favorable alleles of QTLs for TGW significantly decreased GNS, whereas days to heading positively correlated with GNS. Late heading increased the spikelet number per spike, resulting in a higher GNS. Pyramiding of the QTLs for TGW and days to heading also altered the GNS. In conclusion, GNS is a complex trait controlled by many QTLs, and it is essential for breeding to design.

Supplementary information

The online version contains supplementary material available at 10.1007/s11032-021-01255-8.

SUBMITTER: Mizuno N

PROVIDER: S-EPMC10236116 | biostudies-literature | 2021 Oct

REPOSITORIES: biostudies-literature

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Genetic mechanisms determining grain number distribution along the spike and their effect on yield components in wheat.

Mizuno Nobuyuki N Ishikawa Goro G Kojima Hisayo H Tougou Makoto M Kiribuchi-Otobe Chikako C Fujita Masaya M Nakamura Kazuhiro K

Molecular breeding : new strategies in plant improvement 20211005 10

The number of wheat grains is one of the major determinants of yield. Many quantitative trait loci (QTLs) and some causal genes such as <i>GNI-A1</i> and <i>WAPO-A1</i> that are associated with grain number per spike (GNS) have been identified, but the underlying mechanisms remain largely unknown. We analyzed QTLs for grain number and other related traits using 188 doubled haploid lines derived from the Japanese high-yield variety, Kitahonami, as a parent to elucidate the genetic mechanism deter ...[more]

PMID: 37309314

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Dataset Information

Genetic mechanisms determining grain number distribution along the spike and their effect on yield components in wheat.

Supplementary information

Publications

Genetic mechanisms determining grain number distribution along the spike and their effect on yield components in wheat.

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