Mechanisms of chalky ring formation in rice: Determination of in situ cell water relations and metabolic changes in endosperm cells at osmotic adjustment

2014 Fiscal Year Final Research Report

• Project/Area Number: 24380013
• Research Category: Grant-in-Aid for Scientific Research (B)
• Allocation Type: Partial Multi-year Fund
• Section: 一般
• Research Field: Crop science/Weed science
• Research Institution: National Agriculture and Food Research Organization
• Principal Investigator: WADA HIROSHI 独立行政法人農業・食品産業技術総合研究機構, 九州沖縄農業研究センター・水田作研究領域, 主任研究員 (40533146)
• Co-Investigator(Kenkyū-buntansha): MORITA Satoshi 独立行政法人農業・食品産業技術総合研究機構, 九州沖縄農業研究センター・水田作研究領域, 上席研究員 (40391453)
• Project Period (FY): 2012-04-01 – 2015-03-31
• Keywords: 環境ストレス / 細胞生理計測 / 澱粉代謝

Outline of Final Research Achievements

Dry wind conditions during the grain-filling stage increase ring-shaped chalkiness in rice (Oryza sativa L.) to deteriorate grain quality. The objective of this study was to understand the physiological cause(s) on chalky ring formation induced by dry wind conditions. Kernel growth was maintained even at short-term moderately low water potential by osmotic adjustment with increased assimilate input. It has been suggested that starch synthesis was partially inhibited, but with little starch degradation. In addition, this short-term dry wind was thought to be different from the response at long-term high temperature conditions. Because the events observed at low water potential preceded the packing of starch granules in cells, we concluded that reduced rates of starch biosynthesis play a central role in the events of cellular metabolism altered at osmotic adjustment in advance of chalky ring formation under short-term dry wind conditions.

Free Research Field

作物学