Genetic analysis of panicle branching regulators from wild rice species

2022 Fiscal Year Final Research Report

• Project/Area Number: 19K05980
• 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 Institute of Genetics
• Principal Investigator: Tsuda Katsutoshi 国立遺伝学研究所, 遺伝形質研究系, 助教 (30756408)
• Project Period (FY): 2019-04-01 – 2023-03-31
• Keywords: 野生イネ / 穂分枝制御 / 生存戦略

Outline of Final Research Achievements

Inflorescence branching is an important factor that determines crop yield. Domesticated rice (Oryza sativa) has more panicle branches compared to its wild ancestor O. rufipogon. However, diversity in the regulation of inflorescence branching among wild species remains elusive. Here we focused on Uniaxial (Ux), a panicle branching repressor found in O. rufipogon. We cloned Ux and revealed its distribution among the wild rice population. We also showed that O. rufipogon has Suppressor of Uniaxial (Su), which is a dominant factor that completely suppresses the Ux phenotype.

Free Research Field

植物発生学、育種学

Academic Significance and Societal Importance of the Research Achievements

野生植物の繁殖戦略において次世代に残す種子と自身の植物体維持の間で資源分配調節を行うことは重要である。本研究では野生イネが独自に持つ穂分枝抑制因子Uxを同定した。Uxは特定の野生イネ集団内に分布する傾向があったことから、それらの自生地および生存戦略とUxを介した資源分配が密接に関連することが考えられた。また、野生イネはUxの作用を完全に打ち消す因子Suも持つことが明らかとなり、資源分配を巧妙に調節するための仕組みが備わっている可能性が見えてきた。