Molecular cloning and characterization of pre-harvest sprouting resistance genes for enhancement of environmental adaptability

2019 Fiscal Year Final Research Report

• Project/Area Number: 17K08164
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Research Field: Environmental agriculture(including landscape science)
• Research Institution: Yamagata University
• Principal Investigator: HOSHINO TOMOKI 山形大学, 農学部, 准教授 (20530174)
• Project Period (FY): 2017-04-01 – 2020-03-31
• Keywords: 穂発芽 / イネ / QTL / ファインマッピング / 遺伝子 / 発現解析 / 突然変異体 / TILLING

Outline of Final Research Achievements

Pre-harvest sprouting (PHS) is a phenomenon wherein seeds germinate prematurely during the process of ripening due to high temperature and humidity. PHS resistance is believed to be regulated via a complex molecular mechanism; nevertheless, its overall functioning remains unclear. Given that fine mapping could not detect any genes within the qSdr6a region, we hypothesized that qSdr6a regulates the expression of genes in its vicinity. Gene expression analyses of developing embryos identified GeneX and GeneY as candidate genes for qSdr6a. The genex and geney mutants isolated from the newly created mutant populations exhibited strong inhibitory and promotional effects, respectively, on germination. These results suggest that qSdr6a may be a gene expression regulatory domain. It may induce PHS resistance in rice by negatively and positively regulating the expressions of the GeneX and GeneY, respectively.

Free Research Field

作物育種学

Academic Significance and Societal Importance of the Research Achievements

本研究では、「人間活動の発展」を最終目標に掲げ、「環境調和」からさらに一歩踏み込み、本来、植物自身が環境変動から身を守るために有する機能を強化させる、つまり人為的に「環境適応力を強化させる」ために、特に穀物の「穂発芽耐性能力」に焦点をあて、「穂発芽耐性」の分子基盤を構築することによって、人間活動を支えるエネルギー源の確保を試みた。さらに、「穂発芽耐性」を付与させることは、穀物の品質劣化を食い止め、穀物の品質向上につながることが期待される。本研究成果は、穀物に「穂発芽耐性＝環境適応力」を付与させることが可能となり、環境変動にも動じない、きめ細やかな穀物の品質向上が可能になるであろう。