Identification of Heterodera cysts by SOD isozyme electrophoresis profiles

Superoxide dismutase (SOD), the enzyme which converts superoxide anions into hydrogen peroxide, has been found to be highly expressed in the cyst stage of a number of Heterodera species likely to occur together in the field. By examining isoforms of this enzyme in polyacrylamide gel electrophoresis, we have been able to show different SOD profiles in six common species of Heterodera (H. avenae, H. cruciferae, H. glycines, H. goettingiana, H. schachtii and H. trifolii). The method is quick and therefore lends itself to routine use in a diagnostic laboratory.