Occurrence of Potato Witches' Broom Caused by a Phytoplasma in Korea

파이토플라스마에 의한 감자빗자루병 발생

Witches' broom symptoms were firstly found on tubers of Solanum tuberosum cv, Deijima, showing dense growth of spindly sprouts in Cheju province, Korea. Plantlets from the diseased plants also produced the typical witches' broom symptoms, having densely-growing small leaves when they became adult plants. At the later stages the diseased leaves were blightened. Presence of phytoplasma in plant tissues was confirmed by DAPI-staining fluorescence microscopy and electron microscopy, exhibiting its localization in sieve tubes of stem, petiole, and midrib. This is the first report of potato witches' broom in Korea.