Periodic Reporting for period 3 - RUSTWATCH (RustWatch: A European early-warning system for wheat rust diseases)
Okres sprawozdawczy: 2021-05-01 do 2022-09-30
A core activity is to provide a better understanding of pathogen biology by faster and more efficient diagnostic methods to detect new rust races and genotypes, which enables us to investigate pathogen population changes, including potential exotic incursions of rust strains into Europe, and to study the role of pathogen aggressiveness, temperature adaptation, and Berberis spp. as sexual host as driver of evolution. This has been possible by strengthening the collaboration among European rust diagnostic laboratories, e.g. new procedures for alignment of experimental procedures and interpretation of results, and exchange and compilation of genotypic and phenotypic data using the facilities provided by the WheatRustToolbox.
The case study approach has allowed us to investigate the threats of invasive rust races at the regional scale and suggest IPM-based prevention and control options adjusted to the relevant agronomical practices and environmental conditions in the considered region. For instance, after the extensive 2019-yellow rust epidemics in Denmark (one of the case study regions) farmers responded by dramatic changes in varietal distribution. Due to the emergence of a new yellow rust race, more than 60% of the wheat area was deployed by highly susceptible varieties in 2019. This figure has dropped below 10% in the current growing season, where yellow rust ‘resistant’ varieties are deployed on 80% of the winter wheat area. Inspired by RustWatch results and other project activities, the use of variety mixtures in winter wheat has expanded rapidly in several countries, e.g. France and Denmark in particular, where 39% of the winter wheat area is covered by high yielding variety mixtures in the growing season 2022/23.
The project has proven that efficient and long-term prevention and control of rust diseases in wheat is dependent of a system approach, which in addition to pathogen diagnostic laboratories involves key stakeholders within plant breeding, variety testing (VCU), and rapid and efficient dissemination of results including agricultural advisory services working with individual plant growers. Short-term prospects for efficient genetic control of yellow rust are promising, whereas additional efforts are required to develop new and high yielding varieties with durable resistance to leaf (brown) rust and to stem (black) rust in particular. A European infrastructure beyond research for complementation of national efforts for pathogen monitoring and resistance phenotyping allowing interpretation of pathogen dispersal, evolution and potential impact on yield and quality at the continental scale is highly recommended. The early-warning system developed is generic and could be applicable for additional crops and windborne pathogens, which to a large extent can be controlled by host resistance. A set of general recommendations for plant health in relation to non-regulated and wind dispersed crop pathogens has been developed.