Canker cypress

Diterpene phytotoxins sphaeropsidins A—F, tri- and tetracyclic unrearranged pimarane skeleton, are isolated from Sphaeropsis sapinea, a fungus that causes a canker disease of Italian cypress. Sphaeropsidin A is the major toxic substance showing nonhost-selective phytotoxic activity326 (Figure 36). 

Heimler, D. Pieroni, A., High-performance quantitative thin-layer chromatography of flavonoid glycosides and biflavonoids of Cupressus sempervirens in relation to cypress canker, Chromatographia, 1991, 31, 247-250. 

Several species of Seiridium, including S. cardinale, S. cupressi and S. unicorne, are associated with the canker diseases of cypress, Cupressus sempervirens. The phytotoxic metabolites include the butenolides seiridin (8.61) and isoseiridin (8.62) and their 7 -hydroxy relatives as well as the sesquiterpenes seiricardine A (8.63) and B (8.64). Solutions of these sesquiterpenes when applied to leaves produce chlorosis, browning and death of the leaves. 

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