Chapter 27 - Bacterial pathogens of potato

Abstract

In this chapter, the biology and pathology of the major bacterial diseases including blackleg, stem rot, bacterial soft rot, bacterial wilt, bacterial ring rot and common scab are discussed in detail. Thereafter, measures to control bacterial diseases by production of pathogen-tested seed, reduction of inoculum and helpful agronomic practices are addressed. In general, bactericides are ineffective as crop protection agents, and their usefulness for disinfecting seed tubers is limited. Immunity to bacterial diseases is generally not available, although some cultivars show tolerance and various levels of resistance. Control of some bacterial diseases such as those caused by the quarantine pathogens, Ralstonia solanacearum and Clavibacter michiganensis ssp. sepedonicus, can only be achieved by costly statutory measures. The chances for control and eradication of bacterial diseases after introduction into new areas largely depend on the available infrastructure enabling their detection and trace back to source. Availability of adequate instruments to detect and identify the pathogens along with the means to contain and eradicate infection sources is an important consideration for addressing new pathogen incursions. The use of pathogen-tested minitubers should be favored, and the number of field generations reduced to limit the build-up of bacterial populations. Monitoring of inoculum carried in or on seed by laboratory testing is recommended if it can be done in a cost-effective manner.