IN VITRO METHODS FOR TESTING POTATO CLONES AGAINST SOFT ROT ERWINIAE

Backleg and bacterial soft rot is caused by bacteria of the Erwiniae family. Three types of Erwinia are known to affect potatoes: Erwinia carotovora subsp. atroseptica, Erwinia carotovora subsp. carotovora and Erwinia chrysanthemi. At the moment the chemical protection is not solved. However, the sensitivity of produced cultivars are different, resistant cultivars are not available for management of these diseases. The resistance in potato usually comes from wild Solanum species. In our Research Centre we have bred potatoes for more decades. Our breeding work based on using of the different wild Solanum species bearing resistance or tolerance against Erwinia species. The aim of our research is connected with disease: working out new in vitro methods for evaluation of the level of resistance or tolerance against potato blackleg and tuber soft rot. We infected in vitro plantlets. For evaluation of the data, disease rating was used. By the help of disease ratem we quantified the differences among potato clones. We separated sensitivity categories. On the basis of our results the in vitro methods may be suitable for fast test of the breeding materials, clones or cultivars against different Erwinia-strains.