Induction of haploids in eastern little tuna, Euthynnus affinis, and application to fish breeding materials

2023 Fiscal Year Final Research Report

• Project/Area Number: 21K14916
• Research Category: Grant-in-Aid for Early-Career Scientists
• Allocation Type: Multi-year Fund
• Review Section: Basic Section 40040:Aquatic life science-related
• Research Institution: Fisheries Research and Education Agency (2022-2023); Ehime University (2021)
• Principal Investigator: Endoh Mitsuru 国立研究開発法人水産研究・教育機構, 水産技術研究所(南勢), 研究員 (20897714)
• Project Period (FY): 2021-04-01 – 2024-03-31
• Keywords: 人工授精 / 染色体操作 / 雄性発生 / 雌性発生

Outline of Final Research Achievements

In this study, we conducted fundamental research on artificial fertilization and chromosome manipulation for the breeding of eastern little tuna, Euthynnus affinis, a related species of the bluefin tuna. First, we examined the adequate procedure for ovulated egg storage for efficient artificial fertilization. Ovulated eggs with high productivity were achieved 3 hour after egg collection when maintained in Hanks' solution at 20 ℃. Additionally, we determined the optimum UV irradiation dose for inducing gynogenetic and androgenetic haploid by ploidy analysis using the cell analyzer.

Free Research Field

遺伝育種

Academic Significance and Societal Importance of the Research Achievements

スマの排卵卵の短期保存と人工授精手法の確立により、選抜育種において計画的な交配を行うことが可能となった。また、半数体誘起のように人工授精前に配偶子への処理を伴う染色体操作や、人工授精直後の顕微注入処理が必要なゲノム編集など、育種技術をスマの育種に適用する上でも有用な知見となった。さらにスマ半数体の誘起は、倍加半数体の作出に繋がるだけでなく、半数体ゲノム利用したゲノム情報解析を可能にするなど、育種を支える周辺情報の整備への応用も期待される。