INFECTIONS WITH VARIOUS TYPES OF ORGANISMS STIMULATE TRANSCRIPTION FROM A SHORT PROMOTER FRAGMENT OF THE POTATO GST1 GENE

By histochemical GUS staining, we demonstrate that transcription from a short promoter fragment of the potato gst1 gene is locally induced a fter infection of a host plant with various types of pathogenic or sym biotic organisms. This regulatory unit is not active in noninfected ti ssues, except root apices and senescing leaves. Measuring the expressi on of a fusion between the promoter fragment and the gus gene in trans genic plants, therefore, allows comparison of the induction of defense reactions in different types of plant-microbe interactions, in one an d the same plant.