explain how the pathogen occurs throughout the whole distribution of the host, and the small natural populations are an area of interest.

“Several studies reported very low differentiation among samples of fungal pathogens of agricultural crops or forestry trees from different localities across a continent.”[2] To further explain, this shows that this fungus affects its host similarly across the continent.

M. amygdalinae distorts the blades and veins of willow, causing irregular spots, bearing the orange yellow uredinia, which is the lesion that forms on the leaf surface.

“After dikaryotization by transfer of spermatia to the receiving structures of compatible mating types, aecia are formed.

The pustule structure formed on the leaf, asexually produce uredospores, which travel by wind dispersal.

“The spread of rust on a willow host takes place during the summer and includes several repeated cycles of clonal propagation of urediniospores.

Willows are not as shade tolerant as most other plants, so they need an open canopy of tree branches to let a good amount of sunlight in.

Rust attacks influence the development of winter dormancy in the host and indirectly frost hardiness”.

It takes a lot of time and effort to control fungal pathogens, so new methods may have to be performed in the case of new infections developing.