Master theses

In order to unravel the regulation of constitutive aerenchyma formation in roots of Juncus effusus, the regulation pathway was compared to that of inducible aerenchyma in maize. Because of the key-role of ethylene in the pathway, the research concentrated on ethylene action. Inhibitors of the ethylene signal transduction pathway (EGTA, W7, neomycin-sulphate and 1-MCP) were used.

To test the specificity of the inhibitors they should be able to counteract an ethylene effect. The ethylene effect used was inhibition of root growth. The only inhibitor that reduced the amount of constitutive aerenhcym without toxic effect on root growth, was 1-MCP. When testing 1MCP for specificity, no inhibiting effect of ethylene or ACC on root growth was found, which contradicts earlier findings.

The involvement of ethylene is in constitutive aerenchyma formation in Juncus effusus is likely, because an ethylene receptor blocker does reduce root porosity. However, the specificity of that reduction is not yet proven.