Research on responsible genes of pre-germination seed vernalization and secondary seed dormancy for elucidating life history plasticity in facultative winter annual weeds.

2022 Fiscal Year Final Research Report

• Project/Area Number: 21K19125
• 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: Niigata Agro-Food University
• Principal Investigator: Yoshioka Toshihito 新潟食料農業大学, 食料産業学科, 教授 (10240243)
• Project Period (FY): 2021-07-09 – 2023-03-31
• Keywords: 種子春化 / 越年草 / 一越年草 / 生活史進化 / 花成遺伝子 / 種子二次休眠 / 雑草性 / 生活史可塑性

Outline of Final Research Achievements

Arabidopsis thaliana (accession Ws) transgenic plants with high expression of PSV1 (Pre-germination Seed Vernalization 1) that is a candidate gene of the seed vernalization in Erigeron canadensis, a facultative winter annual of Compositae, showed early flowering traits without seed chilling. In addition, in A. thaliana (accession Col), wild type seeds were induced into secondary dormant states by chilling for 30 days, but seeds of mutants with over expression of PSV1 homolog were not induced the secondary dormancy although the seeds had been chilled. These results highly suggest that PSV1 is the responsible gene of seed vernalization and that regulation of PSV1 expression has been involved in the life history differentiation between facultative and obligate winter annuals. The primary characteristic of weeds is plasticity of their life histories. Facultative winter annual shows larger life history plasticity than obligate one. Thus, PSV1 should be the essential factor of weediness.

Free Research Field

雑草学、植物生理学、植物生態学

Academic Significance and Societal Importance of the Research Achievements

春化は緑体春化と催芽種子春化、および未発芽種子春化に分けられる。緑体春化と催芽種子春化の分子機構は、近年、解明が進んだが、未発芽種子春化については不明である。本研究からPSV1が高い確度で未発芽種子春化の責任遺伝子であることが明らかになった。これは新奇花成システムの発見につながる可能性がある。未発芽段階の種子で発芽後植物体の花成が制御できれば、農業技術としての応用範囲が広く、社会貢献が期待される。キク科植物であるヒメムカシヨモギの遺伝子PSV1が、分子系統樹では遠いクレードに属するアブラナ科植物のシロイヌナズナで花成に機能することは、植物進化学的にも興味深い。