Introgression of chromosomal segments conferring early heading date from wheat diploid progenitor, Aegilops tauschii Coss., into Japanese elite wheat cultivars

• Published in: PloS one Vol. 15; no. 1; p. e0228397
• Main Authors: Takumi, Shigeo, Mitta, Seito, Komura, Shoya, Ikeda, Tatsuya M, Matsunaka, Hitoshi, Sato, Kazuhiro, Yoshida, Kentaro, Murai, Koji
• Format: Journal Article
• Language: English
• Published: United States Public Library of Science 27.01.2020; Public Library of Science (PLoS)
• Subjects: Aegilops - genetics; Aegilops tauschii; Agricultural research; Biology and Life Sciences; Bread; Breeding; Chromosomes; Chromosomes, Plant - genetics; Climate change; Cultivars; Diploids; Diploidy; Future climates; Gene sequencing; Genes; Genetic Introgression; Genetic polymorphisms; Genomes; Genotyping; Global temperature changes; Goat grass; Grain; Grain size; Grains; Harvesting; Inbreeding; Nucleotides; Plant breeding; Quantitative Trait Loci; Rainy season; Research and Analysis Methods; Ribonucleic acid; RNA; RNA sequencing; Seeds; Sequence Analysis, RNA; Shape recognition; Single nucleotide polymorphisms; Single-nucleotide polymorphism; Triticum - genetics; Triticum - growth & development; Wheat; Whole Genome Sequencing; Japan
• ISSN: 1932-6203; 1932-6203
• DOI: 10.1371/journal.pone.0228397

The breeding of agriculturally useful genes from wild crop relatives must take into account recent and future climate change. In Japan, the development of early heading wheat cultivars without the use of any major gene controlling the heading date is desired to avoid overlap of the harvesting time before the rainy season. Here, we backcrossed two early heading lines of a synthetic hexaploid wheat, derived from a crossing between durum wheat and the wild wheat progenitor Aegilops tauschii, with four Japanese elite cultivars to develop early heading lines of bread wheat. In total, nine early heading lines that showed a heading date two to eight days earlier than their parental cultivars in field conditions were selected and established from the selfed progenies of the two- or three-times backcrossed populations. The whole appearance and spike shape of the selected early heading lines looked like their parental wheat cultivars. The mature grains of the selected lines had the parental cultivars' characteristics, although the grains exhibited longer and narrower shapes. RNA sequencing-based genotyping was performed to detect single nucleotide polymorphisms between the selected lines and their parental wheat cultivars, which revealed the chromosomal regions transmitted from the parental synthetic wheat to the selected lines. The introgression regions could shorten wheat heading date, and their chromosomal positions were dependent on the backcrossed wheat cultivars. Therefore, early heading synthetic hexaploid wheat is useful for fine-tuning of the heading date through introgression of Ae. tauschii chromosomal regions.