Progress of endoreduplication in the developing endosperm of rice (Oryza sativa)

2015 Fiscal Year Final Research Report

• Project/Area Number: 26850010
• Research Category: Grant-in-Aid for Young Scientists (B)
• Allocation Type: Multi-year Fund
• Research Field: Crop production science
• Research Institution: National Agriculture and Food Research Organization
• Principal Investigator: KOBAYASHI Hidekazu 国立研究開発法人農業・食品産業技術総合研究機構, 西日本農業研究センター・水田作研究領域, 主任研究員 (60360450)
• Project Period (FY): 2014-04-01 – 2016-03-31
• Keywords: 水稲 / 胚乳 / 核内倍加 / 細胞周期

Outline of Final Research Achievements

Endoreduplication is the phenomenon by which the DNA content of the nucleus is increased by successive rounds of chromosomal DNA replication, without subsequent mitosis. In the present study, I examined the progress of endoreduplication in the developing endosperm of various cultivars of rice (Oryza sativa), under different growth conditions. Within the same cultivar, ploidy (the copy number of chromosomes) was higher in the intermediate region of the endosperm than in the central and peripheral regions, and proportional relationships between ploidy and cell size were found. Significant differences in endoreduplication were found among the cultivars, and correlations between mean ploidy and cell size of the cultivars were found. The progress of endoreduplication was affected by growth conditions; high temperature reduced both endoreduplication and seed weight in Hinohikari. These results demonstrate that endoreduplication plays an important role in the development of rice endosperm.

Free Research Field

作物学