Diversity and genetic factors in rice photosynthetic induction by time series parallel analysis

2023 Fiscal Year Final Research Report

• Project/Area Number: 21K19104
• Research Category: Grant-in-Aid for Challenging Research (Exploratory)
• Allocation Type: Multi-year Fund
• Review Section: Medium-sized Section 39:Agricultural and environmental biology and related fields
• Research Institution: Tokyo University of Agriculture and Technology
• Principal Investigator: Adachi Shunsuke 東京農工大学, (連合)農学研究科(研究院), 准教授 (30717103)
• Co-Investigator(Kenkyū-buntansha): 田中 佑 岡山大学, 環境生命自然科学学域, 准教授 (50634474)
• Project Period (FY): 2021-07-09 – 2024-03-31
• Keywords: 光合成誘導 / ゲノムワイド関連解析 / 気孔伝導度 / 炭酸固定 / 変動光 / 自然変異 / イネ

Outline of Final Research Achievements

We evaluated the diversity of photosynthetic responses (photosynthetic induction) of 166 Japanese rice cultivars after stepwise irradiation increase. We found that Aikoku Mochi, a native variety, showed remarkably rapid photosynthetic induction. This was attributed to a rapid increase in photosynthetic activity in the leaves immediately after high light irradiation and a rapid increase in stomatal conductivity. The rapid photosynthetic induction of Aikoku Mochi showed increased growth under fluctuating light condition relative to constant light condition. Genome-wide association study revealed genomic regions on chromosomes 3 and 5 involved in the rapid induction of photosynthesis. Identification of the causal gene is expected to elucidate the regulatory mechanism of photosynthesis induction in plants.

Free Research Field

作物生理学

Academic Significance and Societal Importance of the Research Achievements

光に対する光合成の応答性を高めることは、光エネルギーを無駄なく利用し、作物の生産性を高めることに貢献する。本研究で我々は、在来品種である愛国もちが日本のイネ品種の中で突出して迅速な光応答性を高めることを発見し、その生理・遺伝メカニズムの一端を明らかにした。また野外のような変動する光環境では、他の品種にくらべて植物の成長性にも優れることを見出した。愛国もちは、イネ品種の物質生産性の改良のための育種素材として役立つと期待される。