2025-08-22 北海道大学

図 1. 避暑型水稲栽培の作型モデル。
<関連情報>
- https://www.hokudai.ac.jp/news/2025/08/post-2029.html
- https://www.hokudai.ac.jp/news/pdf/250822_pr3.pdf
- https://www.jstage.jst.go.jp/article/jsbbs/advpub/0/advpub_25002/_article
非感光性イネ品種において早生化を制御する遺伝的及び環境的要因は、穂揃い、不時出穂及び分げつラグ期に影響する Genetic and environmental regulation of early heading in photoperiod-insensitive rice: impacts on heading synchrony, premature heading, and tiller development lag
Shuntaro Sakaguchi, Yuya Ota , Md. Imdadul Hoque, Yuji Kishima
Breeding Science Advance online publication: July 31, 2025
DOI:https://doi.org/10.1270/jsbbs.25002
Abstract
The process by which day length affects rice heading has been studied on a molecular basis; however, little is known about the traits that occur with heading, such as heading synchrony, premature heading, and day of the determined effective tiller number. These traits vary more in photo-insensitive (photo-In) lines than in day-length-sensitive lines. We used photo-in lines to study the associations of these traits with heading earliness and the influence of the earliness genes and the different latitudes. The results of this study showed these traits were significantly correlated with the earliness of first days to heading (F-DTH) among the photo-In lines. A wider range of F-DTH was observed in Sapporo than Iga when used the same photo-In varieties, which was confirmed under artificial conditions. We identified five significant quantitative trait loci (QTL) for F-DTH among the photo-In lines. A QTL with a major effect associated with F-DTH, heading synchrony, and premature heading was detected on chromosome 4. Using photo-In lines, we propose a heat-tolerance strategy for early cultivation in low-latitude regions.


