Disease control to achieve stable food production has been one of the challenges to crop scientists for nearly a century. The ocurrence of large-scale epidemics, common in the first half of the twentieth century, has decreased thanks to an improved understanding of disease epidemiology and the genetic basis of host-pathogen interactions, to the search for resistance genes, and to the development of cultivars with built-in resistance to important diseases and pests. The race-specific type of resistance based on major genes has been improperly used to control rapidly evolving pathogens (e.g., the rusts of wheat), resulting in boom-and-bust cycles that make it necessary to replace cultivars a short time after their release or to implement chemical control strategies. Durable resistance to important diseases and pests is often based on the interaction of a few minor, additive genes. Breeding strategies to combine such genetic resistance with other, desirable traits must become a primary goal of breeding programs aimed at achieving long-term control of major diseases and pests and ensuring stable food production gains while protecting the environment. Diseases and pests have posed major threats to stable production of many food crops for centuries. An improved understanding of pathogen epidemiology, combined with the identification and utilization of genetic resistace in crop varieties, has helped prevent or reduce disease epidemics common until 30 or 40 years ago. This success can be attributed to numerous independent research findings that have led to improved genetic control of diseases and pests. Better approaches can be developed from the lessons learned from the successes and failures and from knowledge not available previously.

Global Wheat Program

Text in English

INT0610