Cronartium rusts are among the most destructive pathogens on pines. Cronartium flaccidum has caused severe damage on young Scots pines in 2000s. The rust spreads via alternate host plants. Variation in rust resistance is high between alternate hosts. In this project, we aim to identify the contents of secondary metabolites in rust-resistant and susceptible alternate host species, and to test the effect of these substances on growth of Cronartium in vitro, in vivo and in the field. We will also describe the endophytic species composition of leaves in susceptible and resistant plants and test the effect of the leaf chemicals to growth of the endophytes. The research creates foundation for initiatives on biochemical aspects of rust-host associations. Substances that reduce the growth of Cronartium may be used as new biochemical products against rust diseases and other pathogens. The project is planned to last between 2020-2023 with total costs of ca. 643 390 euros.

2020

2023