59 research outputs found
Antifungal metabolites produced by <i>Trichoderma viride</i> against <i>Sclerotium rolfsii</i>
In this comunication we report our progress regarding the isolation and characterization of new
antifungal metabolites from this strain of T. viride
Phytotoxic metabolites produced by Botryosphaeriaceae involved in grapevine trunk diseases
Fungi belonging to the Botryosphaeriaceae family are well known as cosmopolitan pathogens, saprophytes and endophytes and occur on a wide range of hosts including grapevine.
More recently, a new species of Lasiodiplodia was isolated from declining grapevines in Sardinia (Italy). This still undescribed species showed to produce in liquid culture several phytotoxic secondary metabolites. In this communication the chemical and biological characterization of these bioactive secondary metabolites is discussed
together with their role in the pathogenesis process
Diplofuranones A and B, two further new 4-monosubstituted 2(3<i>H</i>)-dihydrofuranones produced by <i>Diplodia corticola</i>, a fungus pathogen of cork oak
Two new 4-monosubstituted 2(3H)-dihydrofuranones, named diplofuranones A and B, were
isolated from liquid cultures of Diplodia corticola, a plant pathogenic fungus causing a canker
disease of cork oak (Quercus suber L.). The same fungus also produces several metabolites such
as the diplopyrone, the (3S,4R)-trans- and the (3R,4R)-cis-4-hydroxymellein, the sapinofuranone
B and its (S,S)-enantiomer, the well known sphaeropsidins A-C, and the diplobifuranylones A
and B. The diplofuranones A and B were characterised, using spectroscopic (essentially NMR
and MS techniques) methods, as the 4-[(1E,3E)-5-hydroxyhexadienyl]butan-4-olide and its
corresponding 3,4-dihydro side chain derivative. The stereochemistry of the stereogenic
secondary hydroxylated carbon of the side chain of diplofuranone A was determined by
application of Mosher’s method and proved to be R. Diplofuranone A tested at 0.2 mg mL-1 on
non-host plant did not show phytotoxic activity
Determinazione dei residui di Deltametrina nelle ciliegie
This paper describes the determination of residues of the insecticide Deltamethrin in cherries growing in the Bonnanaro area near Sassari (Sardinia - Italy). The analytical procedure for the isolation of the insecticide was developed. The quantitative determinations were carried out by HPLC, with UV detector at 220 nm, on a Perkin-Elmer C18-HS3 column with acetonitrile - water (75: 25) as the mobile phase. A rapid decrease of the concentration
of the insecticide with ti me was ascertained; three days
after from the treatment the values were significantly lower than those required by the italian law
Indagine fitosanitaria nel comprensorio di Sarroch, Villa S. Pietro e Pula (prov. di Cagliari) in relazione all'attività di uno stabilimento petrolifero
A five-year investigation (1988-92) of the phytosanitary situation in the Sarroch, Villa S. Pietro
and Pula areas, belonging to the Cagliari district, where the SARAS-oil company has been operating
for a long time, was carried out.
Various degrees of damage caused by fungi, bacteria, viruses, insects, acari and by abiotic agents
(edaphic and climatic) were detected on trees and herbaceous plants.
Investigations on possible S02 damages by means of phytosanitary observations and chemical
analysis, clearly showed no noxious effects of this gas on both cultivated and spontaneous plants
Phytotoxic metabolites produced by fungi involvedin cork oak decline
Diplodia corticola, anamorph of Botryosphaeria corticola Phillips, Alves et Luque, and
Biscognauxia mediterranea (De Not.) O. Kuntze (= Hypoxylon mediterraneum) have often been
associated with serious decline phenomena, which have been affecting the cork oak forest in Italy
and other Mediterranean countries for several years. Diplodia corticola is widespread in Sardinian
oak forests, and can affect plants of different ages, inducing symptoms which include dieback,
cankers and vascular necrosis. These studies may provide information which could be useful for understanding the chemistry
and the biology governing the relationship between these fungi and their hosts. Further studies
should aim to also evaluate the ecological role of these substances
Pinofuranoxins A and B, Bioactive Trisubstituted Furanones Produced by the Invasive Pathogen Diplodia sapinea
Two new bioactive trisubstituted furanones, named pinofuranoxins A and B (1 and 2), were isolated from Diplodia sapinea, a worldwide conifer pathogen causing severe disease. Pinofuranoxins A and B were characterized essentially by NMR and HRESIMS spectra, and their relative and absolute configurations were assigned by NOESY experiments and computational analyses of electronic circular dichroism spectra. They induced necrotic lesions on Hedera helix L., Phaseolus vulgaris L., and Quercus ilex L. Compound 1 completely inhibited the growth of Athelia rolfsii and Phytophthora cambivora, while 2 showed antioomycetes activity against P. cambivora. In the Artemia salina assay both toxins showed activity inducing larval mortality
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