Development of Aerenchyma in Root and Hypocotyl of Annual Wild Soybean(Glycine soja Sieb.et Zucc.)

In order to elucidate the mechanism of waterlogging tolerance of annual wild soybean(Glycine soja Sieb.et Zucc.),we observed the aerenchyma development of main root and hypocotyl of seedling by using Paraffin section.The results showed that the aerenchyma begun to form at 3～5 weeks after sowing,and developed completely from root to stem in 2 weeks after forming.The aerenchyma of annual wild soybean was firstly formed at the position near to root collar,and then extended to root tip and stem.The forming patterns were similar,but the forming time of aerenchyma differed within the materials growing in different regions.