Localization of ornithine decarboxylase in barley leaves infected by brown rust (Puccinia hordei)

Ornithine decarboxylase (ODC) was localized in healthy and brown rust-infected leaves of barley using a radiolabelled inhibitor of this enzyme. No ODC activity was detected in healthy leaves. In diseased leaves, high concentrations of ODC were present in rust pustules, particularly in urediniospores. The possible significance of these observations with regard to retention of chlorophyll in association with rust pustules is discussed.