Study on the genotype associatedd with thermosensitive fertility restoration in cytoplasmic male sterility

2023 Fiscal Year Final Research Report

• Project/Area Number: 21H02159
• Research Category: Grant-in-Aid for Scientific Research (B)
• Allocation Type: Single-year Grants
• Section: 一般
• Review Section: Basic Section 39010:Science in plant genetics and breeding-related
• Research Institution: Hokkaido University
• Principal Investigator: Kubo Tomohiko 北海道大学, 農学研究院, 教授 (40261333)
• Co-Investigator(Kenkyū-buntansha): 北崎 一義 北海道大学, 農学研究院, 助教 (60532463) ; 松平 洋明 国立研究開発法人農業・食品産業技術総合研究機構, 北海道農業研究センター, 主任研究員 (90549247)
• Project Period (FY): 2021-04-01 – 2024-03-31
• Keywords: テンサイ / 細胞質雄性不稔性 / 稔性回復遺伝子 / 温度感受性

Outline of Final Research Achievements

Cytoplasmic male sterility (CMS) is prerequisite for the hybrid breeding of sugar beet. It has been believed that sugar beet CMS expresses constitutively, but its stable expression depends on the specific nuclear genotype. Other genotypes restore male fertility or confer conditional male sterility that expresses only when the plant suffers heat. This project aims to clarify the genetic mechanism of this conditional male sterility and to see its potential use for the application of practical breeding. Sugar beet plants showed very different phenotypes in northern and southern parts of Japan when they have male sterility-inducing mitochondria and certain genotypes. These genotypes were further dissected into individual genes. One of the constituents is an allele of known gene but its novel function was revealed in this project. The chromosomal location of another gene was identified. Altogether, the mechanism of the conditional male sterility involves several nuclear genes.

Free Research Field

遺伝育種科学

Academic Significance and Societal Importance of the Research Achievements

テンサイOwen型CMSはテンサイハイブリッド育種に用いられている。育種の現場においては雄性不稔発現により純度の高い雑種を得ている。そのため、安定したCMS発現を促すような選抜が加えられてきた。著者らは本研究開始以前にテンサイCMS発現を不安定化させる核遺伝子型の存在を明らかにしていたが、本研究によりその核遺伝子型の解明を進めることができた。さらにテンサイCMS発現を栽培環境によって制御できる可能性を確かめることができた。これは温度感受性CMSを利用した新しい採種システム実用化に向けた前進である。