The resistance to waterlogging of three Eucalyptus species : Effect of waterlogging and an ethylene-releasing growth substance on E. robusta, E. grandis and E. saligna.

Seedlings of Ecalyptus grandis W. Hill ex Maiden were found to be more resistant to waterlogging than those of Eucalyptus robusta Sm. and seedlings of both species were more resistant than those of Eucalyptus saligna Sm. Resistance depended on the stress avoidance mechanism of adventitious root formation. The ethylene-releasing growth substance 2-chloroethylphosphonic acid (ethephon) applied to non-flooded plants was used as a tool to study the role of ethylene in the response of plants to waterlogging. Plant height and total dry weight decreased linearly with plant ethylene content. There was no difference between the species in their response to ethephon.