SCANNING ELECTRON-MICROSCOPY OF THE INTERACTIONS BETWEEN ERWINIA-HERBICOLA PV GYPSOPHILAE AND GYPSOPHILA-PANICULATA

Ultrastructural studies of interactions between Erwinia herbicola pv. gypsophilae and gypsophila plants showed that the bacterial pathogen m ultiplied rapidly and colonized gypsophila cuttings within 2 days. Fou rteen days after inoculation, the plant tissue turned tumorigenic and a gall formed. Scanning electron microscopy showed E. gypsophilae cell s densely occupying the plant xylem elements. Bacteria were found in a ssociation with fibrils which might be used by bacterial cells for att achment to plant cells. Substantial numbers of fibrils were also clear ly seen on calli cell surfaces.