Occurrence of Powdery Mildew on Safflower Caused by Sphaerotheca fuliginea in Korea

ABSTRACT

The powdery mildew of safflower (Carthamus tinctorius L.) extensively occurred at 1999 at the experimental farm of Kyongsangnam-do Agricultural Research and Extension Services. Both sides of the leaves and the older stems were covered with the fungus, and then the leaves and stems turned yellow. The conidia, conidiophores and perithecia were observed on the leaf lesion. Perithecia were ellipsoidal, 80-117microm in diameter. Asci were subglobose and 84~99x59~73microm in size. Ascospore were ellipsoidal to ovoid, and 15~34x11~23microm in size. Conidia were ellipsoid to barrel-shaped, 25~37x11~22microm in size and formed in long chains. The causal organism was identified as Sphaerotheca fuliginea. This is the first report on powdery mildew of safflower caused by Sphaerotheca fuliginea in Korea.