Durability of Plant Resistance to Pathogens and Pests

The methods of management of pathogens and pests have been changing during these years, under the pressure of current societal and political demands. To overcome the drawbacks of chemical control, it is possible to mobilize genetic (i.e. varieties resistant to diseases) and agronomic controlling methods (cultural practices favoring these resistances or reducing the risks of pressure or development of pests). However, the low durability of genetic resistance, which is linked to the adaptation of pathogens, imposes the need to propose solutions in order to improve the durability of genetic resistance. Resistance is said to be durable when its effectiveness lasts for many years in a large spatial environment, at high pressure from the pathogen, favoring, a priori, the selection of virulent variants. The combination of quantitative and qualitative resistance is among the best solutions, but the strategy for deploying the R genes is an interesting track to follow.

Keywords: Durability of plant resistance to pathogens, Gene pyramiding, Gene rotation, Quantitative resistance, Qualitative resistance, R-gene deployment strategy.