Dry matter production in relation to root plastic development, oxygen transport, and water uptake of rice under transient soil moisture stresses

作者：Suralta Roel Rodriguez; Inukai Yoshiaki; Yamauchi Akira^*

来源：Plant and Soil, 2010, 332(1-2): 87-104.

DOI：10.1007/s11104-009-0275-8

• Aerenchyma
• Drought
• Lateral roots
• Oxygen transport
• Waterlogging
• Water use

Drought and waterlogging are important abiotic stresses negatively affecting plant growth and development. They are transiently recurring in rainfed lowlands and in water-saving system practicing intermittent irrigation. This study aimed to determine the contribution of plastic development and associated physiological responses of roots to shoot dry matter production under transient soil moisture stresses. To minimize effect of genetic confounding, a selected line (CSSL47) drawn from 54 chromosome segment substitution lines (CSSL) of Nipponbare (japonica type) carrying an overlapping chromosome segments of Kasalath (indica type), was used and compared with the recurrent parent Nipponbare. Under transient droughted-to-waterlogged (D-W) conditions, CSSL47 showed greater shoot dry matter production than Nipponbare. This was due largely to its greater root system development through high induction of aerenchyma formation. Consequently, aerenchyma development effectively facilitated the internal diffusion of oxygen (O(2)) to the root tips under sudden waterlogged condition supporting rapid recovery of stomatal conductance, transpiration, and photosynthesis. Likewise, CSSL47 showed greater shoot dry matter production than Nipponbare under transient waterlogged-to-droughted (W-D) conditions. This was due to CSSL47's greater root system development through more initiation of L type lateral roots that effectively maintained soil water uptake. This in turn sustained higher stomatal conductance, transpiration, and photosynthesis. Results implied that utilization of CSSLs could precisely reveal that root plastic development in response to transient soil moisture stresses contributed to the maintenance of shoot dry matter production.

• 出版日期2010-7