Breeding for pest resistance: a difficult and current challenge

Abstract

In order to face the new challenges of agriculture, genetic improvement is called to play an important role for making production processes sustainable also from an environmental and economic point of view. In the coming years it will be necessary to produce more but in a scenario of decreasing natural resources and also with a reduction of chemical inputs. In the last fifty years, the integration of dierent techniques and the development of in vitro regeneration methods and molecular strategies has allowed the definition of new tools for genetic improvement. The genomic knowledge of the last decades have, in fact, innovated the tools for the development of programs of genetic improvement, both in terms of availability of markers for assisted selection or for genomic selection, and in terms of knowledge on the function of genes responsible for specific agronomic traits such as the resistance to biotic stress. These molecular methods allow to obtain cisgenic plants, can help to modify target sequences through genome editing, and can be considered as complementary to traditional breeding methods. At the same time, they can overcome some of the limits of crossing and selection, especially those related to their long duration and the unpredictability of the results in terms of changed characteristics. In this contribution we describe the main methods of genetic improvement and the main strategies that can be used to improve the resistance of plants to insects.