Phytobacteriology

About our Research

 

 

This research programme focuses on bacterial diseases of plants.  Our interest has primarily been on Pantoea ananatis and related Pantoea  species. P. ananatis is responsible for bacterial blight and die-back of Eucalyptus, brown stalk rot of maize and occurs on onion seed in South Africa.  Our studies have centred on taxonomy and on developing rapid and reliable methods of distinguishing between the species of this genus.  Other elements currently under investigation include understanding the epidemiology and biology of P. ananatis in South Africa as well as identifying pathogenicity factors and understanding its life as a phytopathogen to a greater extent. Our group recently sequenced the genome of the virulent Eucalyptus  P. ananatis strain LMG20103.

 

A third, and more recent focal area is on the Pectobacterium-Dickeya disease complex on potatoes in South Africa. The two species in this complex are responsible for soft rot, aerial stem rot and blackleg of potatoes. The objectives of this study are to determine the socio-economical impact of the disease in South Africa, the genetic diversity of species isolated from potatoes in South Africa, to develop a rapid, sensitive detection method for use in the potato seed industry and to develop guidelines for integrated control and avoidance of the disease. 

 

Figure 1. Genome diagram of Pantoea ananatis.

Figure 2. Typical symptoms of bacterial blight of Eucalyptus

 

Figure 3. Typical symptoms of bacterial blight of Eucalyptus

Figure 4. Typical symptoms of bacterial blight of Eucalyptus