Plant and Soil

, Volume 251, Issue 2, pp 351–359

Formation and function of secondary aerenchyma in hypocotyl, roots and nodules of soybean (Glycine max) under flooded conditions


DOI: 10.1023/A:1023036720537

Cite this article as:
Shimamura, S., Mochizuki, T., Nada, Y. et al. Plant and Soil (2003) 251: 351. doi:10.1023/A:1023036720537


Flooding is a major problem in many areas of the world and soybean is susceptible to the stress. Understanding the morphological mechanisms of flooding tolerance is important for developing flood-tolerant genotypes. We investigated secondary aerenchyma formation and function in soybean (Glycine max) seedlings grown under flooded conditions. Secondary aerenchyma, a white and spongy tissue, was formed in the hypocotyl, tap root, adventitious roots and root nodules after 3 weeks of flooding. Under irrigated conditions aerenchyma development was either absent or rare and phellem was formed in the hypocotyl, tap root, adventitious roots and root nodules. Secondary meristem partially appeared at the outer parts of the interfascicular cambium and girdled the stele, and then cells differentiated to construct secondary aerenchyma in the flooded hypocotyl. These morphological changes proceeded for 4 days after the initiation of the flooding. After 14 days of treatment, porosity exceeded 30% in flooded hypocotyl with well-developed secondary aerenchyma, while it was below 10% in hypocotyl of irrigated plants that had no aerenchyma. When Vaseline was applied to the hypocotyl of plants from a flooded treatment to prevent the entry of atmospheric oxygen into secondary aerenchyma, plant growth, especially that of roots, was sharply inhibited. Thus secondary aerenchyma might be an adaptive response to flooding.

flooding toleranceoxygen deficiencyoxygen transport systemsecondary aerenchymasecondary meristem (phellogen)soybean (Glycine max)

Copyright information

© Kluwer Academic Publishers 2003

Authors and Affiliations

  • S. Shimamura
    • 1
  • T. Mochizuki
    • 2
  • Y. Nada
    • 2
  • M. Fukuyama
    • 2
  1. 1.Graduate School of Bioresource and Bioenvironmental SciencesKyushu UniversityUSA
  2. 2.Faculty of Agriculture, Graduate SchoolKyushu UniversityUSA