Further degradation product of hyperforin from Hypericum perforatum (St John's Wort)

Repeated examination of the aerial parts of Hypericum perforatum yielded a new degradation product of hyperforin (1) namely deoxyfurohyperforin A (2), together with the previously identified furohyperforin (3), furoadhyperforin (4), furohyperforin A (5a and 5b), pyrano[7,28-b]hyperforin (6) and 3-methyl-4,6-di(3-methyl-2-butenyl)-2-(2-methyl-1-oxopropyl)-3-(4-methyl-3-pentenyl)-cyclohexanone (7). The antimicrobial activity of the compounds 3, 5a and 5b, 6 and 7 was tested against Staphylococcus aureus, Candida albicans, Bacillus subtilis and Escherichia coli.     

Allelic polymorphism and inheritance of MdACS1 and MdACO1 genes in apple (Malus × domestica Borkh.)

The allelic polymorphism and inheritance of MdACS1 and MdACO1 genes were analysed in 28 apple cultivars, which were derived from reciprocal crosses of the following parental pairs: ‘Golden Delicious’ × ‘James Grieve’, ‘Golden Delicious’ × ‘Jonathan’, ‘Cox's Orange Pippin’ × ‘Golden Delicious’, ‘Cox's Orange Pippin’ × ‘Jonathan’. Polymorphisms were detected by PCR and the use of two restriction enzymes (BamH1 and RsaI). In addition, new primers were designed for the further discrimination of MdACO1 alleles. Two alleles of MdACS1 gene (MdACS1‐1 and MdACS1‐2) and three alleles of MdACO1 gene (a, b and c) were detected. Cloning and sequencing of MdACO1 alleles confirmed a high conservation and some differences within the coding regions and helped to reconcile between different numbering systems. Observed segregations confirmed that alleles a, b and c belonged to the MdACO1 gene. It is apparent that polymorphisms within the MdACS1 and MdACO1 genes could aid cultivar genotyping and identification and, furthermore, that the MdACS1‐2/2 genotype is correlated with a long apple storage life.     

Production and characterization of amphihaploid hybrids between <Emphasis Type="Italic">Nicotiana wuttkei</Emphasis> Clarkson et Symon and <Emphasis Type="Italic">N. tabacum</Emphasis> L

Nicotiana wuttkei Clarkson and Symon discovered in the 1990s in Australia may be of potential interest to breeders as it carries resistance to Peronospora hyoscyami de Bary. The crossability between N. wuttkei (2n = 4x = 32) and three N. tabacum (2n = 4x = 48) cultivars (‘Puławski 66’, ‘Wiślica’ and ‘TN 90’) and the morphology and cytology of their amphihaploid hybrids (2n = 4x = 40) were studied. Seeds were produced only when N. wuttkei was used as the maternal parent, but under normal germination all seedlings died. Viable F₁ hybrids of N. wuttkei × N. tabacum cv. ‘Puławski’ and N. wuttkei × N. tabacum cv. ‘Wiślica’ were obtained only by in vitro cotyledon culture. The amphihaploid plants were intermediate between the parents for most morphological traits. In 46.4% of the PMC’s, only univalents were present. The remainder of the cells had 1–5 bivalents and 1–2 trivalents. In spite of a detectable frequency of monads (2.6%), dyads (2.6%) and triads (4.5%), the hybrids were self and cross sterile.     

Dothistroma pini—Eine Gefahr fürPinus sylvestris?

Zusammenfassung Dothistroma pini wurde auf einer ganzen Reihe von Kiefernarten festgestellt. Sporenl?nge und das gelegentliche Auftreten der HauptfruchtformScirrhia pini belegen das Vorhandensein der var.linearis. Konidien wurden von M?rz bis in den November gefunden, besonders zahlreich von April bis Juni. Erstmals, festgestellt wurde das Pathogen aufPinus cembra, P. aristata, P. koraiensis undP. tabuliformis, allerdings ist anzunehmen, da? die Infektion dieser Arten nur unter starkem Infektionsdruck stattfindet und die wirtschaftliche Bedeutung des Pilzes in diesen F?llen sehr begrenzt ist. Gleiches gilt offensichtlich auch fürPinus sylvestris. Diese Kiefernart wird nach unseren Beobachtungen auch bei engem Kontakt mit sehr stark infizierten Schwarzkiefern nur unbedeutend oder überhaupt nicht befallen. In diese Richtung deuten auch die ersten Ergebnisse eines Infektionsversuches, bei demP. sylvestris symptomfrei blieb, w?hrendP. nigra z. T. sehr starke Symptome einer Infektion zeigte. Eine nennenswerte Sch?digung vonP. sylvestris konnte bei Freilandbeobachtungen in keinem Falle festgestellt werden. Gegenteilige Hinweise in der Literatur sind auf Verwechselungen (des Pathogens oder des Wirtes) zurückzuführen.

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Dothistroma pini—a danger for Pinus sylvestris?

Summary Dothistroma pini was found on several different pine species. The length of the conidia and the existence of the teleomorph, which sometimes could be noticed, prove the presence of the var.linearis of the fungus. Conidia were detected between March and November, in high quantities especially from April to June. For the first time, the pathogen has been mentioned onPinus cembra, P. aristata, P. koraiensis andP. tabuliformis. It must be assumed, however, that these species only become infected under high infection pressure. That means, that the economic importance of the pathogen is very limited in these cases. Obviously the same is true withPinus sylvestris. After our observations this pine species was little or not at all infested even when in direct contact with heavily attackedP. nigra-plantations. The result of an infection experiment, in whichP. sylvestris did not show any symptoms whereasP. nigra was partly heavily attacked, points in the same direction. Damages toPinus sylvestris worth mentioning could not be found during observations in the field. Opposite indications from the literature can be explained by mistaking pathogens or host species.

     

Geographic information system (GIS) application for windthrow mapping and management in Iezer Mountains, Southern Carpathians

Windthrow problem is a difficult task for the forest managers in the Romanian Carpathians and especially in Iezer Mountains. The last windthrow, in July 2005, affected about 370 ha within the study area and left unprotected large slopes with important declivities (20-30°). In our study, we try to propose a tool for forest management, in order to control and minimize the negative effect of wind upon the mountain forest ecosystem. The digital data input derived from forestry data (forest stand typology, age, canopy coverage index, forest productivity class) and from the forest biotope features (soil and topography parameters). The main goal was to find a more objective way for digital layer reclassification in order to obtain the windthrow areas susceptibility map for the Iezer Mountains. Each digital layer has its own weight within the analysis and one of them was difficult to be modeled (the wind features). A statistical approach was developed on the basis of local phenomena and the windthrow features in the Romanian Carpathians. This allowed us to obtain the reclassification conditions for each digital layer. Forest canopy typology and soil features (mainly its volume) were considered as the key factors for the windthrow occurrence analysis. The final windthrow susceptibility map was validated with the help of the statistic occurrence of windthrow areas within each susceptibility class and after a field check of the sites. The result was encouraging, because 92.5% of the windthrow areas fall into the highest windthrow susceptibility class.     

Antimicrobial activity of Chenopodium botrys essential oil

Essential oil, isolated by hydrodistillation from Chenopodium botrys aerial parts, expressed significant bactericidal and fungicidal activity against selected strains of microorganisms.     

Mass spectrometric dereplication of nitrogen-containing constituents of black cohosh (Cimicifuga racemosa L.)

Black cohosh preparations are popular dietary supplements among women seeking alternative treatments for menopausal complaints. For decades, triterpene glycosides and phenolic acids have dominated the phytochemical and biomedical research on this plant. In this study, we provide evidence that black cohosh contains an unexpected and highly diverse group of secondary nitrogenous metabolites previously unknown to exist in this plant. Using a dereplication approach that combines accurate mass measurements, database searches and general knowledge of biosynthetic pathways of natural products, we identified or tentatively identified 73 nitrogen-containing metabolites, many of which are new natural products. The identified compounds belong to several structural groups including alkaloids, amides or esters of hydroxycinnamic acids and betains. Among the alkaloids, several classes such as guanidino alkaloids, isoquinolines and β-carbolines were identified. Fragmentation patterns for major compound classes are discussed, which provides a framework for the discovery of these compounds from other sources. Identification of alkaloids as a well-known group of bioactive natural products represents an important advance in better understanding of the pharmacological profile of black cohosh.     

Free radical scavenging activity of Achillea alexandri-regis extracts

The antioxidative potential of Achillea alexandri-regis has been studied by measuring the influence of herb extracts on hydroxyl and superoxide radicals' quantity in different in vitro systems. The ethyl acetate extract exhibited hydroxyl radical scavenging activity in all tested biological system (liver homogenate, hemolyzed blood, serum and postmitochondrial liver fraction), whereas butanol extract reduced hydroxyl radicals significantly only in the postmitochondrial liver fraction. Both extracts showed superoxide radical scavenging effect only in hemolyzed blood.     

Parasitoid complex of Phyllonorycter robiniella (Clemens, 1859) (Lepidoptera, Gracillariidae) in Serbia

In a study of the parasitoid complex of the locust leaf miner Phyllonorycter robiniella (Clemens, 1859), 23 species of its parasitoids were recorded at 18 localities in Serbia. The parasitoid species included 2 species of the family Braconidae, 1 of the family Eupelmidae, and 20 of the family Eulophidae. The recorded species of parasitoids are polyphagous; in addition to Ph. robiniella, they also develop on other species of leaf miners as primary; primary and secondary; or primary, secondary, and tertiary parasitoids. Among the recorded species of parasitoids, the most significant were the species Pholetesor bicolor, Pholetesor nanus, Sympiesis sericeicornis, Sympiesis acalle, Minotetrastichus frontalis, Pediobius saulius, and Baryscapus nigroviolaceus. The parasitoids were found to have a strong effect on the abundance of Ph. robiniella because they reduced more than 50% of its larvae and pupae in the majority of study samples.