Studies on the Changes in the Distribution of Cell Wall Modification in Floral and Fruit Abscission Zones during Fruit Development in Tomato.

2015 Fiscal Year Final Research Report

• Project/Area Number: 25440125
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Research Field: Plant molecular biology/Plant physiology
• Research Institution: University of Tsukuba
• Principal Investigator: IWAI Hiroaki 筑波大学, 生命環境系, 准教授 (30375430)
• Project Period (FY): 2013-04-01 – 2016-03-31
• Keywords: 離層 / 器官脱離 / 細胞壁 / エクスパンシン / XTH / キシログルカン / リグニン

Outline of Final Research Achievements

Regulation of cell wall metabolism may play an important role in abscission, but it is not well understood. In the study, we used immunohistochemistry to visualize changes in the distributions of xyloglucan metabolism-related enzymes in the AZs of pollinated and unpollinated flowers, and in ripened fruits. During floral abscission, we observed a gradual increase of expansin in the AZ. However, during floral abscission, we observed a large 1 day post anthesis peak in XTH in the AZ, which then decreased. During fruit abscission, unlike during floral abscission, no AZ-specific expansin and XTH were observed. Although lignification was seen in the AZ of over-ripe fruit pedicels, secondary cell wall-specific cellulose synthase signals were not observed. These results suggest that expansin and XTH play important, but different roles in the floral abscission process and cellulose metabolism-related enzymes do not play important roles in the AZ prior to fruit abscission.

Free Research Field

植物生理学