The fungus Puccinia coronata f. sp. lolii causes crown rust in hybrid ryegrass, manifesting as the formation of uredinia on the leaves. The disease is most active in the second half of summer and autumn, reducing the productivity of grass stands.
In the reference
28
varieties
crop Hybrid ryegrass,
where this is mentioned in the description.
The causal agent of crown rust, Puccinia coronata, infects hybrid ryegrass, manifesting as characteristic uredinia with urediniospores on the surface of leaf blades. Pathogen development is most often observed in the second half of the growing season and during the autumn period, especially in the presence of plant stress factors or insufficient mineral nutrition.
In breeding practice and variety testing, the degree of crop infection is assessed on a nine-point scale, where 1 point corresponds to an immune or highly resistant state, and 9 points to high susceptibility with numerous pustules. Due to the lack of specific resistance genes, ryegrass breeding is aimed at achieving field resistance of populations, which is recorded in variety characteristics as a quantitative indicator.
General information about the subject — on the page
Rust.
Varieties of Hybrid ryegrass mentioned in the description
Selection based on the description text, not on official evaluation: these data are absent from registers. For specific variety details, please refer to its profile.