A Decade of Hop Powdery Mildew in the Pacific Northwest

Fig. 3. Hop cones infected with Podosphaera macularis and displaying signs and symptoms of cone early maturity. (A) Hop cone browning due to powdery mildew; (B) diffuse hyphae and infection of bract; (C) Conidiophores and conidia of P. macularis on strig of cone; and (D) Profuse sporulation of P. macularis on strig of cone displaying cone early maturity.



Image from Plant Health Progress article:
A Decade of Hop Powdery Mildew in the Pacific Northwest