XVI International Botanical Congess

The amphibious leafless sedge Eleocharis vivipara is develops C4-like traits under terrestrial conditions and C3-like traits under submerged conditions. This plant provides a model system to study the developmental aspects of Kranz anatomy and photosynthetic function. We examined the cellular pattern of expression of the C4 genes in the mature and developing culms by in situ hybridization technique. In the mature culms of the terrestrial form, mRNAs for the C4 genes were found in the mesophyll cells at high levels although they were not detectable in the submerged form. The results from the analysis of the developing culms indicate the different expression of the C4 genes between the two growth forms was progressive during culm ontogeny. We will also report the effect of plant hormones on the expression pattern of the C4 genes and Kranz anatomy.