New isolates of the blackleg fungus[Phoma lingam, perfect stage Leptosphaer
ia maculans (Desm.) Ces. et de Not.], virulent to the traditionally resista
nt brown mustard (Brassica juncea), produce L-valyl-L-tryptophan anhydride,
a 2,5-dioxopiperazine different from those produced by blackleg isolates v
irulent to canola (B. napus and B. rapa). (C) 1998 Elsevier Science Ltd. Al
l rights reserved.