First Report of the Early Spore Stages of Sunflower Rust, Caused by <i>Puccinia helianthi</i>, in Nebraska

Fig. 1. Thin section of infected sunflower leaf showing flask-shaped pycnia on the top leaf surface, and aecial cups and developing aeciospores on the bottom leaf surface.



Image from Plant Health Progress article:
First Report of the Early Spore Stages of Sunflower Rust, Caused by Puccinia helianthi, in Nebraska