Effects of aerenchyma formation on the root porosity, lateral root development, total water uptake and shoot biomass accumulation of global magic rice under seedling-stage drought stress

Abstract

© 2017, International Society for Southeast Asian Agricultural Sciences. All rights reserved. Drought stress negatively affects rice productivity due to the lack of water necessary for growth and development. Previous studies have shown that the formation of root cortical aerenchyma (RCA) can influence the development of lateral roots, which aid in the uptake of water and accumulation of biomass during drought. The present study evaluated aerenchyma formation in several genotypes of global Multi-Parent Advanced Generation Intercross (MAGIC) population in rice, and its relationship with lateral root development, root porosity, total water uptake, and shoot biomass accumulation during seedling-stage drought stress. The following methods were used in the study: aerenchymatous regions were measured in pixels using GIMP v.2.8.14 (GNU Image Manipulation Program); percent lateral roots were determined using a root scanner coupled by Winrhizo v. 2005, and root porosity was estimated using the buoyancy method. Half of the genotypes studied exhibited 2-35% RCA development under drought-stress (DS), compared with 7-25% under the well-watered (WW) treatment. Mean percent RCA was also higher in DS (14.03%) than in WW (12.98%), but was not significantly different at p=0.053. In addition, high RCA genotypes, like MG-6865, did not show highest or lowest shoot biomass nor total water uptake for both treatments. Thus, RCA formation in the global MAGIC rice genotypes did not influence total water uptake, shoot biomass accumulation, root porosity, and the production of lateral roots. Under seedling-stage during severe drought stress, formation of aerenchyma was observed to be a mere response to the absence of water through cell lysis. Therefore, root traits other than RCA might be more correlated with drought-tolerance in the studied genotypes.

Source or Periodical Title

Journal of the International Society for Southeast Asian Agricultural Sciences

ISSN

8593132

Page

192-202

Document Type

Article

Subject

Biomass, Global MAGIC rice, Water uptake

This document is currently not available here.

Share

COinS