occurrence of Phytopythium vexans Causing Stem Rot on Anthurium andraeanum in Korea

Mi-Jeong Park1,*   Chang-Gi Back1   Jong-Han Park1   

1Horticultural and Herbal Crop Environment Division, National Institute of Horticultural and Herbal Science, Rural Development Administration, Wanju 55365, Korea

Abstract

In 2017, wilting symptom was observed on seedlings of Anthurium andraeranum in Youngin, Korea. Brownish lesions with water soaking were developed on the stems and roots of the infected plants. The stems and leaves wilted and finally died. One fungal isolate was obtained in pure culture. Morphological features and nucleotide sequences of internal transcribed spacer rDNA and cytochrome oxidase subunit II mt DNA were analyzed. The results of this study indicated that the fungus is identified as Phytopythium vexans. Pathogenicity tests showed the isolate was pathogenic to the seedlings of A. andraeanum. To our knowledge, this is the first report of P. vexans causing stem rot on A. andraeanum in Korea.

Figures & Tables

Fig. 1. Characteristics of stem rot caused by on . A, Diseased seedlings with wilting symptom; B, Lower parts of affected plants showing lesions of brown discoloration and rotting; C, Discolored vascular tissues; D, Inoculated plant(left) showing wilting symptom and uninoculated plant(right) showing no visible symptoms in pathogenicity test; E, Colony grown on PDA after incubation for 4 weeks; F, Subglobose sporangium with papilla; G, Globose sporangium; H, Zoospores. (scale bars: F-H = 10 μm).