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The investigation was conducted in a 32-year-old pine stand, growing on a fresh coniferous site in western Poland. The strip roads in the stand had been designed and cut along tree rows 5 years prior to the investigation. The analysis focused on trees growing at 12 strip roads, in 3-meter-wide stripes on both sides of the strip roads and in control zones, half-way between each two neighbouring strip roads. The trees growing on the stripes along the strip roads were divided into three zones corresponding to tree rows. The first zone (I) was formed by trees growing in the row directly at the strip roads, while the zones two (zone II) and three (zone III) were formed by trees growing in the second and third rows of trees away from the strip roads, respectively, on both sides of the strip roads. The average distances of the zones two and three from the strip roads were 1.5 and 3 m, respectively. The diameters at breast height (DBH) of all the trees growing in the respective zones were measured. Moreover, the widths of the strip roads were measured, which resulted in dividing the strip roads into two groups: the wider strip roads (average width 3.6 m) and the narrower ones (average width 2.9 m). The statistical analysis showed significant differences in DBH values between the analysed zones, for nine of the strip roads. Both in the case of the wider strip roads, as well as in the case of the narrower ones, the trees growing directly along the strip roads were usually thicker than the more distant trees. A statistically significant difference between the DBH values of trees from zone I and II was found for one strip road. In most cases the trees from zone I were statistically thicker than the trees growing in the control zone.
Fungal invasion of Scots pine phloem and sapwood was investigated during a period of 15 weeks following attack by the pine shoot beetle, Tomicus piniperda (L.). The study was conducted in Mielec-Mościska, where the pine trees were heavily damaged by shot-feeding of T. piniperda. In order to determine the species richness and occurrence frequency of fungi associated with T. piniperda in temporal succession, living and trap trees infested by T. piniperda were used. Results revealed great diversity of fungi associated with T. piniperda, including 3758 cultures and 57 fungi species. The most important groups of fungi were the blue-stain fungi and molds, including mainly Penicillium, Trichoderma and Mucor genera. Among ophiostomatoid fungi, Ophiostoma minus and O. piceae were the dominant species. Occasionally isolated species were Leptographium lundbergii, L. procerum, L. wingfieldii, Graphium pycnocephalum and Graphium sp. ‘W’. Molds and pathogenic O. minus were the first invaders of both phloem and sapwood, however molds were more frequently isolated from phloem and sapwood at a depth of 5 mm. Ophiostoma piceae and L. lundbergii followed O. minus in the sapwood invasion. These species were successively replaced by L. wingfieldii, L. procerum and Graphium species in the later stages of fungal invasion in pine sapwood.
63 congeners of chloronaphthalene represented by 53 peaks fractionated and separated using two-dimensional HPLC and DB-17 capillary column were quantified using HRMS in ten samples of pine needles collected in 1999 around Tokyo Bay in Japan. Similarities and differences of chloronaphthalene concentrations and patterns between 10 sampling sites were studied using multivariate analysis. Total PCN concentrations ranged from 250 to 2100 pg/g wet weight. Except for one site, tri- and tetra-CNs highly dominated (from 54 to 80%) in CN homologue patterns of pine needles. At the easternmost site near the town of Tateyama in Chiba Prefecture the contribution from octaCN was ~20 %, while that of tri- and tetra-CNs ~42 %. Pine needles sampled from the sites around the innermost part of Tokyo Bay showed the highest load of PCNs. A multivariate analysis using the three most significant principal components explained 91% of the total variance in the measurement data. The greatest positive loading to PC1 is from the CN congeners nos. 13, 14/21/24, 15, 16, 17, 18, 19, 20, 22/23, 25, 26, 27, 28/36, 29, 30/32, 31, 33/34/37, 35, 40, 42, 43/45, 44, 47, 49, 50, 51, 52/60, 53, 57, 58, 59, 61, 62, 64, 65, 66/67, 68, 69, 71 and 72, and explains 65% variance in the data set. For PC2 the largest positive loading is from CNs nos.74 and 75, and negative load from CN nos. 38, 41, 46 and 48, which explains 17% of the variance. In case of PC3 the largest negative load is from CNs nos. 54, 56, 63, 70 and 73. A profile of the combustion process related CN congeners measured such as nos. 44, 48 and 54 didn’t show any specific trend implying pollution from diffused sources of various types.
The study presents a new strategy of synthesis of the pine-tree lappet moth sex pheromone via hydrolysis of the (5Z,7E)-1,1-diethoxy-5,7-dodecadiene (propheromone) and their using in biological tests with pheromone traps. The field trials showed that a sticky delta traps with propheromone at dose of 2.4 mg was the most suitable for monitoring of the population of the pine tree lappet moth.
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