Fig. 1.

Cronartium ribicola life cycle with five stages of spore development. a Blisters on the infected white pine stem; b Aeciospore; c Aeciospore germination; d Rust fungus growth on an infected Ribes leaf; e Urediniospores; f Telia on Ribes leaf; g One-year-old susceptible seedling ~6 months (March) post needle infection by basidiospores; h A typical canker on western white pine stem ~20 months post infection on needles. The four rust development stages sampled for comparative analysis of rust fungal transcriptomes are indicated by red letters