Verification of the effect of root aerenchyma on environmental stress tolerance and elucidation of its mechanism in genus Zea

2022 Fiscal Year Final Research Report

• Project/Area Number: 20K05976
• 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: Mano Yoshiro 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, グループ長 (20355126)
• Co-Investigator(Kenkyū-buntansha): 中園 幹生 名古屋大学, 生命農学研究科, 教授 (70282697)
• Project Period (FY): 2020-04-01 – 2023-03-31
• Keywords: 通気組織 / テオシント / トウモロコシ / 耐湿性 / ストレス耐性

Outline of Final Research Achievements

Root aerenchyma is an important trait for improving flooding tolerance in upland crops, because it plays a role of a pathway for transporting oxygen from the shoot to the root tip when the root system becomes oxygen-deficient due to flooding. We performed detailed mapping of the capacity to form constitutive aerenchyma in teosinte, a wild relative of maize with highly flooding tolerance, and obtained several candidate genes by comprehensive expression analysis of genes expressed in the cortex. In addition, in the comparison of photosynthesis-related traits under dry conditions, we showed the relationship between aerenchyma formation and drought tolerance. Furthermore, as observed in rice, we found that aerenchyma formation and lateral root formation in the nodal roots of teosinte is also regulated by auxin.

Free Research Field

植物遺伝育種学

Academic Significance and Societal Importance of the Research Achievements

本研究において、畑作物の耐湿性向上に重要な形質である通気組織形成能に関する遺伝子の近傍のDNAマーカーと、皮層で発現する遺伝子の網羅的発現解析により候補遺伝子が得られた。これらの情報は、今後の通気組織形成機構の全容解明につながることから学術的価値は高いと言える。さらに、通気組織形成が耐湿性だけではなく乾燥耐性などの環境ストレス耐性の向上に寄与する可能性が示されたことから、通気組織形成遺伝子の導入によるマルチストレス耐性トウモロコシ品種の育成に向けた育種戦略を示すことが出来た。