Stem Rot of Sweet Potato (Ipomoea batatas) Caused by Sclerotium rolfsii in Korea

Research in Plant Disease 2013;19(2):118-120.
Published online June 30, 2013.

Sclerotium rolfsii에 의한 고구마 흰비단병

김주희 ( Ju Hee Kim ) , 김신철 ( Shin Chul Kim ) , 정성수 ( Seong Soo Cheong ) , 최규환 ( Kyu Hwan Choi ) , 김두연 ( Du Yeon Kim ) , 심홍식 ( Hong Sik Shim ) , 이왕휴 ( Wang Hyu Lee )

Stem Rot of Sweet Potato (Ipomoea batatas) Caused by Sclerotium rolfsii in Korea

Ju-Hee Kim1*, Shin-Chul Kim2, Seong-Soo Cheong1, Kyu-Hwan Choi1, Du-Yeon Kim1, Hong-Sik Shim3 and Wang Hyu Lee1

¹Division of Climate Change, Jeollabuk-do Agricultural Research and Extension Services, Iksan 570-704, Korea
²Plant Medical Research Center, Chonbuk National University, Jeonju 561-756, Korea
³Crop Protection Division, National Academy of Agricultural Science, Rural Development Administration, Suwon 441-707, Korea

Received: March 08, 2013 Revised: May 28, 2013 Accepted: June 11, 2013

Abstract

During the early spring of 2007 to 2009, stem rot of sweet potato (Ipomoea batatas L.) caused by Sclerotium rolfsii occurred in seedling stage grown in plastic film house at Iksan. In seedling stage of sweet potato, symptoms were initially appeared in yellowing and then the seedlings were eventually wilted. The fungus produced abundant white silky mycelium on infected tissues and soil line. Seedlings were very susceptible and died quickly once they were infected. The whole area of a petridish was rapidly covered with white mycelium on agar medium. Sclerotia began to produce after 7 days of mycelial growth and white sclerotia quickly melanized to a dark brown coloration. The causal agent isolated from the diseased plants was identified as Sclerotium rolfsii Saccardo on the basis of the morphological and cultural characteristics. All isolates of S. rolfsii caused similar symptoms on the host petioles by artificial inoculation.

Key Words: Sclerotium rolfsii, Stem rot, Sweet potato