PUTAMINOXIN, A PHYTOTOXIC NONENOLIDE FROM PHOMA-PUTAMINUM

Phoma putaminum, the causal agent of leaf necrosis of Erigeron annuus, a common weed of field and pasture, produced toxic metabolites when g rown in liquid culture. The main phytotoxin, named putaminoxin, was is olated and characterized using spectroscopic and chemical methods as ( SS)5-hydroxy-9-propyl-6-nonen-9-olide, a new 10-macrolide. When assaye d on leaves of host and non-host plants, putaminoxin showed a wide ran ge of toxicity, with leaves of E. annuus being most sensitive.