Essential-Oil Variability in Natural Populations of Pinus mugo Turra from the Julian Alps.

The composition and variability of the terpenes and their derivatives isolated from the needles of a representative pool of 114 adult trees originating from four natural populations of dwarf mountain pine (Pinus mugo Turra) from the Julian Alps were investigated by GC-FID and GC/MS analyses. In total, 54 of the 57 detected essential-oil components were identified. Among the different compound classes present in the essential oils, the chief constituents belonged to the monoterpenes, comprising an average content of 79.67% of the total oil composition (74.80% of monoterpene hydrocarbons and 4.87% of oxygenated monoterpenes). Sesquiterpenes were present in smaller amounts (average content of 19.02%), out of which 16.39% were sesquiterpene hydrocarbons and 2.62% oxygenated sesquiterpenes. The most abundant components in the needle essential oils were the monoterpenes δ-car-3-ene, ß-phellandrene, α-pinene, ß-myrcene, and ß-pinene and the sesquiterpene ß-caryophyllene. From the total data set of 57 detected compounds, 40 were selected for principal-component analysis (PCA), discriminant analysis (DA), and cluster analysis (CA). The overlap tendency of the four populations suggested by PCA, was as well observed by DA. CA also demonstrated similarity among the populations, which was the highest between Populations I and II.

Influence of Pleurotus ostreatus inoculation on wood degradation and fungal colonization.

The influence of Pleurotus ostreatus inoculation on wood degradation and on fungal community structure was studied. The experiments were performed on an organically poor fly ash deposit covered with a 10 cm layer of beech wood chips inoculated with P. ostreatus isolate ZIM76. Compared to non-inoculated wood chips, inoculation increased the temperatures and relative humidities and, in the first 6 months, accelerated Klason lignin degradation by 9% and also, after 17 months, increased iron translocation into wood chips by 30%. After 6 months, PCR-DGGE showed 22-28 and 13-21 fungal taxa in non-inoculated and P. ostreatus-inoculated beech chips, respectively. The differences in number of taxa and in the fungal community structure (based on Dice coefficient) between non-inoculated and inoculated wood chips diminished with time. The results indicate that the naturally occurring processes of wood degradation are as efficient as those occurring in sites inoculated with P. ostreatus.

Species-Specific Primers for Eutypella parasitica, the Causal Agent of Eutypella Canker of Maple.

Eutypella parasitica was recently reported in Europe for the first time, and this study reports the molecular evaluation of the internal transcribed spacer (ITS)1/5.8S/ITS2 regions of 68 isolates of the fungus obtained in pure culture with polymerase chain reaction restriction fragment length polymorphism (RFLP). The RFLP patterns of all isolates proved identical and the restriction profiles served to differentiate E. parasitica from Eutypa lata, another pathogenic member of the family Diatrypaceae. Low intraspecific variability was detected in the sequenced ITS1/5.8S/ITS2 regions of eight Eutypella parasitica isolates originating from different hosts and geographical locations. Based on this ITS region, EpR/F primers specific to E. parasitica were constructed and tested with a wide range of fungal isolates. The EpR/F primer pair successfully amplified the expected fragment size of 341 bp from isolates of E. parasitica and also directly from infected maple wood shavings. The RFLP patterns and species-specific primers represent a step toward routine, large-scale, and rapid molecular diagnostics and identification of E. parasitica.