Towards the end of the 1950s, public and private research began creating genetic material which was resistant to diseases and insects. This research, which was initiated in America, intensified in Europe and Asia, and was recognised as a priority in Europe. Starting with resistance to phytopathogenic fungi, research then went on to explore viruses, bacteria and insects.
There are now almost 150 host pathogen and pest combinations across forty cultivated species, which are used for breeding programmes based on identified resistance genes. A breeding academy for disease resistance has also been created in Europe in response to some of the sanitary problems that are developing at this time of major agroecological intensification.
Monogenic resistance
For many years, breeding programmes were oriented towards high-level monogenic resistance in an effort to solve major phytosanitary problems.
Polygenic resistance
Failing to obtain high-level monogenic resistance which was sufficiently durable, research was oriented towards quantitative and partial polygenic resistances, called intermediate resistances, the aim being to associate resistance with other production factors to prevent rapid resistance breakdown.
Insect resistance
Plant breeding for insect resistance has proven difficult due to the absence of genetic symptoms of simple resistance. Nevertheless, aphid resistance genes have been bred for melons (Vat Aphis gosypii resistance gene) and lettuce (Nasonovia resistance). Despite some resistance breakdown being observed, these two resistances have shown to be high-level and sufficiently durable.
Programmes are underway for other vegetable species insects, with research focusing on diversified combat mechanisms (leaf structure, hairs, exudates, etc.).
This area of research and plant breeding for genetic disease and insect resistance has therefore been a major success, and has become an essential tool across the world.