Previous View
APSnet Home
Phytopathology Home



Induction of Common Scab Symptoms in Aseptically Cultured Potato Tubers by the Vivotoxin, Thaxtomin. C. H. Lawrence, Research Station, Agriculture Canada, Fredericton, New Brunswick, Canada E3B 4Z7; M. C. Clark(2), and R. R. King(3). (2)Tweedale Centre, University of New Brunswick, Fredericton, New Brunswick, Canada E3B 6H6; (3)Research Station, Agriculture Canada, Fredericton, New Brunswick, Canada E3B 4Z7. Phytopathology 80:606-608. Accepted for publication 5 January 1990. Copyright 1990 The American Phytopathological Society. DOI: 10.1094/Phyto-80-606.

Inoculation of aseptically cultured minitubers with cell-free extracts from scab lesions of field-grown and cultured tubers infected with Streptomyces scabies reproduced symptoms typical of the common scab disease. Isolation and fractionation of the active components in tissue extracts by a combination of normal and reversed phase thin-layer chromatography yielded two active compounds. These have been designated thaxtomin A and thaxtomin B and characterized as unique 4-nitroindol-3-yl containing 2,5-dioxopiperazines. These phytotoxic principles satisfy all of the basic criteria of vivotoxins.