Elucidation of the genes involved in Fe excess response mechanism and enhancement of Fe excess tolerance in rice

2020 Fiscal Year Final Research Report

• Project/Area Number: 18K14367
• Research Category: Grant-in-Aid for Early-Career Scientists
• Allocation Type: Multi-year Fund
• Review Section: Basic Section 38010:Plant nutrition and soil science-related
• Research Institution: Akita Prefectural University (2019-2020); Ishikawa Prefectural University (2018)
• Principal Investigator: Aung May Sann 秋田県立大学, 生物資源科学部, 特任助教 (20799671)
• Project Period (FY): 2018-04-01 – 2021-03-31
• Keywords: 鉄過剰 / イネ / OsNAS3 / ニコチアナミン / シス制御因子 / ストレス耐性

Outline of Final Research Achievements

Iron excess is a major problem in rainfed rice cultivation in acidic soils. I conducted research to elucidate the tolerance mechanism, and obtained the following results. (1) OsNAS3 plays an important role in iron excess tolerance in rice. (2) T-DNA insertion mutant genes whose expressions are highly induced by iron excess were used. They were grown under iron-excess conditions, and the phenotypes were observed, and physiological data were analyzed. The results suggested that target genes play important roles in iron excess tolerance. (3) Using bioinformatics methods, I searched for novel cis-regulatory elements and promoter structures involved in the iron excess response. The results of these studies are expected to contribute to breeding of iron excess-tolerant rice and establishing a cultivation method for rice that avoids iron excess toxicity.

Free Research Field

植物栄養

Academic Significance and Societal Importance of the Research Achievements

世界の 30 %の土壌は酸性土壌であり、特に中国や東南アジアあるいはアフリカの天水稲作地でのイネの生産において深刻な問題となっている。鉄過剰によりイネの収量が1割から5割低下し、まったく収穫できないこともある。毎年世界中で、8000万トンの収量が失われ、400億ドルの経済的損失が引き起こされている。本研究成果は、鉄過剰耐性のイネを育種したり、鉄過剰症を回避するイネの栽培方法を確立することで、鉄分過剰が発生しやすい土壌でのイネの生産性を向上することに、非常に役立つと期待さる。本研究成果をもとに、近い将来、遺伝子導入や品種改良などの様々な方法で、新しい鉄耐性イネが誕生することが期待される。