Introduction: History of research, symptoms, taxonomy of the pathogen, host range, distribution, and impact of stripe rust

Abstract

Stripe rust, caused by Puccinia striiformis, is a disease on cereal crops wheat and barley, some cultivated grasses and many wild grasses. It is an old disease, but is still economically important. Stripe rust is one of the most destructive diseases of wheat worldwide, and can cause huge yield losses or cost big expenses for chemical control. Although currently not as damaging as stripe rust on wheat, stripe rust of barley can cause significant yield losses in localized barley growing regions. Based on the host species specialization of the fungal pathogen, the species of P. striiformis can be separated into different formae speciales, most notably P. striiformis f. sp. tritici causing stripe rust mostly on wheat and P. striiformis f. sp. hordei mostly on barley. The rapid evolution of the pathogen create various races or pathotypes that are more specialized on cultivars of cereal crops with different race-specific resistance genes. This introduction chapter presents general aspects on historical perspectives, taxonomy and host range of the pathogen and distribution and impact of the disease, and the following chapters will focus specific aspects of the pathogen and disease.