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7'-hydroxyseiridin and 7'-hydroxyisoseiridin, 2 New Phytotoxic Delta(alpha,beta)-butenolides From 3 Species of Seiridium Pathogenic To Cypresses
No full textTwo new phytotoxic Delta(alpha,beta)-butenolides, 7'-hydroxyseiridin [1] and 7'-hydroxyisoseiridin [2], were isolated from culture filtrates of three species of Seiridium (S. cardinale, S. cupressi, and S. unicorne). These fungi are associated with the canker diseases of cypress trees (Cupressus sempervirens) in the Mediterranean area. The structures of butenolides 1 and 2 were established using spectroscopic and chemical methods in comparison with seiridin [5] and isoseiridin [6], two phytotoxic metabolites produced in higher concentration by the same fungal species. Necrotic and chlorotic symptoms were produced on cuttings of both host and non-host plants by absorption of 100 or 50 mu M solutions, respectively, of compounds 1 and 2
UN MARCIUME DEL COLLETTO E DELLE RADICI DI GIOVANI OLIVI CAUSATO DA THIELAVIOPSIS BASICOLA
No full textSeiricardine-b and Seiricardine-c, Phytotoxic Sesquiterpenes From 3 Species of Seiridium Pathogenic For Cypress
No full textSeiricardines B and C, two tricyclic toxic sesquiterpenes, were isolated from culture filtrates of Seiridium cardinale, S. cupressi and S. unicorne, three fungi associated with canker disease of cypress (Cupressus sempervirens) in the Mediterranean area. These new toxic compounds are produced in addition to the already known toxins: seiridin, isoseiridin, seiricuprolide, cyclopaldic acid and seiricardine A. Seiricardine B and C are epimeric diastereomers; their structures and those of some key derivatives were established by spectral studies. Assayed on severed twigs of cypress, seiricardine B and C caused leaf chlorosis followed by browning, and chlorosis, respectively; whereas on tomato and bean cuttings they caused chlorosis and necrosis, and chlorosis, respectively. After injection of seiricardine B and C into cortical tissues of young cypress plants, a hypertrophic reaction of the tissues adjacent to the site of injection and a reddish discolouration of distal leaves, and a reddening and longitudinal lesions, respectively, were observed. In the antimicrobial assay, seiricardine B, in comparison to seiricardine C, showed a higher inhibitory effect on mycelial growth of three test fungi
Cyclopaldic Acid, A Major Phytotoxic Metabolite of Seiridium-cupressi, the Pathogen of A Canker Disease of Cypress
No full textA phytotoxic substance was produced in vitro in a relatively high concentration (c. 40 mg/l) by Seiridium cupressi, a fungus that causes a canker disease of cypress (Cupressus sempervirens) and other Cupressaceae in Greece and in other parts of the world. Structural investigations demonstrated that the substance was identical with cyclopaldic acid, an antibiotic known to be a metabolite of some species of Penicillium, Aspergillus and Pestalotiopsis. Absorbed by severed twigs of three species of Cupressus and by cuttings of two herbaceous non-host plants (tomato and mung bean), cyclopaldic acid at concentrations of 10-100 mug/ml induced leaf chlorosis and necrosis. Oat seed germination and root growth of oat seedlings were also reduced to about 50% at 75 and 100 mug/ml, respectively. The compound showed antifungal activity towards species of Botrytis, Fusarium and Geotrichum when assayed at a concentration range from 10 to 100 mug/ml. We believe this to be the first report of cyclopaldic acid as a non-selective fungal phytotoxin. However, its possible role in the pathogenesis of the cypress canker disease has not been established
Chlorosphaeropsidone and epichlorosphaeropsidone, two new chlorinated dimedone methyl ethers isolated from liquid cultures of Sphaeropsis sapinea f. sp. cupressi
No full textNew Phytotoxic Butenolides Produced By Seiridium-cardinale, the Pathogen of Cypress Canker Disease
No full textTwo new butenolides, seiridin andiso-seiridin, were isolated from culture filtrates ofSeiridium cardinale, the pathogen of cypress canker, a destructive disease ofCupressus and relatedConiferae These metabolites were characterized as 3-methyl-4-(2-hydroxyheptyl)-2(5H)-furanone and its 4-(3-hydroxyheptyl) isomer, respectively. Chlorotic, and necrotic symptoms were produced on leaves of either host or non-host test plants by absorption of 0.3 mg/ml solutions of either compound. These also showed antibacterial activity
Two naphtalenone pentaketides from liquid cultures of Phaeoacremonium aleophilum, a fungus associated with esca of grapevine
No full textChlorosphaeropsidone and epichlorosphaeropsidone, two new chlorinated dimedone methyl ethers isolated from liquid cultures of Sphaeropsis sapinea f. sp. cupressi
No full textPOSSIBLE DISSEMINATION OF SPHAEROPSIS SAPINEA (FR.) DYKO E SUTTON F. SP. CUPRESSUS SOLEL ET AL. (DEUTEROMICOTINA) BY PSOCOPTERA PSOCOMORPHA IN ITALY
No full textTwo naphtalenone pentaketides from liquid cultures of Phaeoacremonium aleophilum, a fungus associated with esca of grapevine
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