Genetic analysis of vertical transmission of Epichloe uncinata endphyte in Lolium multiflorum Lam.

2022 Fiscal Year Final Research Report

• Project/Area Number: 20K05989
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Review Section: Basic Section 39010:Science in plant genetics and breeding-related
• Research Institution: National Agriculture and Food Research Organization
• Principal Investigator: Tamura Ken-ichi 国立研究開発法人農業・食品産業技術総合研究機構, 畜産研究部門, 上級研究員 (10414749)
• Co-Investigator(Kenkyū-buntansha): 清 多佳子 国立研究開発法人農業・食品産業技術総合研究機構, 畜産研究部門, 主任研究員 (40391362)
• Project Period (FY): 2020-04-01 – 2023-03-31
• Keywords: イネ科牧草 / イタリアンライグラス / エンドファイト / Epichloe / 相利共生

Outline of Final Research Achievements

Epichloe endophyte (symbiotic fungi) contribute to the improvement of insect resistance of grass species, but the instability of endophyte in plants is a breeding problem. We attempted to elucidate the genetic factors in Italian ryegrass, as a host plant, involved in the transfer of the Epichloe uncinata from plants to seeds in the symbiotic system. However genetic separation on the transfer of endophyte did not occur as initially expected and the endophyte was stably transferred to the seeds. Next, the transfer of E. uncinata from seeds to young seedlings was compared with that of E. occultans, and the results showed that high temperature and/or high humidity treatments significantly reduced the transfer rate of E. uncinata, indicating that the greatest risk of reduced infection rate in the E. uncinate - Italian ryegrass symbiotic system is in the seed storage conditions.

Free Research Field

植物育種学

Academic Significance and Societal Importance of the Research Achievements

イタリアンライグラスとEpichloe uncinata共生系における菌の感染率低下が主に種子保管中に生じることを明らかにしたことで、エンドファイト感染品種の普及のためには、種子中の菌の安定性の高い品種の開発や種子の低温保存の重要性を明確化できた点に社会的意義がある。さらにエンドファイトの宿主特異性に関わりうる成果が得られた点には学術的意義がある。