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991.
Assessing the pathogenic effect ofFusarium, Geosmithia andOphiostoma fungi from broad-leaved trees 总被引:1,自引:0,他引:1
Phytopathogenic effect of Geosmithia pallida, G. langdonii, Ophiostoma grandicarpum, O. querci, two isolates of O. piceae, and two isolates of Fusarium solani was compared using plant growth test (stem and root length of garden cress plants seeded on mycelium-covered potato carrot agar); Ophiostoma spp. and F. solani were isolated from oak, Geosmithia spp. from galleries of Scolytus intricatus on beech. All fungi inhibited more the root elongation than that of stems. F. solani led to plant collapse after briefly stimulating the growth of stem and in one case also root. G. langdonii inhibited stem and root growth to 20% and led to plant collapse. G. pallida inhibited root growth to 25% whereas stem growth was almost unimpaired. Ophiostoma spp. reduced stem growth to approximately 60-80% and root growth to 25-60%. O. piceae and O. querci caused plant collapse after 15-20 d. 相似文献
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Transgenic Research - Until recently, our ability to generate allelic diversity in plants was limited to introduction of variants from domesticated and wild species by breeding via uncontrolled... 相似文献
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Gordana Ćetković Jasna Čanadanović‐Brunet Jelena Vulić Sonja Djilas Vesna Tumbas Šaponjac 《化学与生物多样性》2014,11(11):1861-1870
The total phenol (TPh) and flavonoid contents (TFd), and antioxidant and sensorial properties of linden honey (LH) with dried apricots (20, 30, and 40%) were evaluated. TPh increased 4.3 times for LH40 (from 23.96 to 102.87 mg gallic acid equiv./100 g honey), while increase of TFd was slightly lower, ca. 2.9‐fold for LH40 (from 18.11 to 51.72 mg rutin equiv./100 g honey). Based on HPLC analysis, the most dominant phenolic compound was gallic acid (11.14 mg/100 g honey in LH and 42.65 mg/100 g honey in LH40). In three different assays, the antioxidant activity increased with increasing concentration of apricots in honey. The values varied from 13.36 for LH to 7.06 mg/ml for LH40; the values ranged from 189.83 for LH to 11.23 mg/ml for LH40; the RP0.5 (reducing power) values ranged from 169.00 for LH to 27.60 mg/ml for LH40. Based on the correlation analysis, it is obvious that TPh and TFd were associated with the antioxidant activities of honey samples. A high degree of correlation existed between antioxidant activities of honey samples and TPh (R from 0.945 to 0.996) and TFd (R from 0.805 to 0.934). Obtained scores for individual sensory properties indicated very good quality of honey with dried apricots. 相似文献
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Seasonal effects of environmental variables on photosynthetic activity and secondary xylem formation provide data to demonstrate how environmental factors together with leaf ageing during the season control tree growth. In this study, we assessed physiological responses in photosynthetic behaviour to seasonal climate changes, and also identified seasonal differences in vascular traits within differentiating secondary xylem tissue from three diploid species of the taxonomically complex genus Sorbus. From sampling day 150, a clear physiological segregation of S. chamaemespilus from S. torminalis and S. aria was evident. The shrubby species S. chamaemespilus could be distinguished by a higher photosynthetic capacity between days 150 and 206. This was reflected in its associations with net CO2 assimilation rate (PN), maximum photochemical efficiency of PSII (Fv/Fm), variable‐to‐initial fluorescence ratio (Fv/F0), potential electron acceptor capacity (‘area’) in multivariate space, and also its associations with log‐transformed vessel area and log‐transformed relative conductivity between days 239 and 268. The maximum segregation and differentiation among the examined Sorbus species was on sampling day 206. The largest differences between S. torminalis and S. aria were found on day 115, when the latter species clearly showed closer associations with high values of vessel density and transpiration (E). Sampling day clusters were arranged along an arch‐like gradient that reflected the positioning of the entire growing season in multivariate space. This arch‐like pattern was most apparent in the case of S. chamaemespilus, but was also observed in S. torminalis and S. aria. 相似文献
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Lara Milevoj Kopčinović Ana-Marija Domijan Ksenija Posavac Ivana Čepelak Tihana Žanić Grubišić Lada Rumora 《Biomarkers》2016,21(8):692-698
Context: Increased oxidative burden is found in chronic obstructive pulmonary disease (COPD).Objective: To assess the association of ceruloplasmin, albumin, bilirubin, transferrin, thiols and malondialdehyde (MDA) with stable COPD.Materials and methods: Oxidative stress markers measured in 106 COPD patients and 45 healthy subjects were evaluated.Results: Higher ceruloplasmin and MDA, and lower albumin, transferrin and thiols in COPD patients were found. Ceruloplasmin was the strongest single predictor of COPD. The model combining ceruloplasmin, albumin and thiols improved their individual diagnostic performances.Conclusions: Diagnostic characteristics of ceruloplasmin, albumin, transferrin, thiols and MDA suggest their potential value as additional tools in disease diagnosis. 相似文献
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Věra Pavelková Řičánková Jan Riegert Eva Semančíková Martin Hais Alžběta Čejková Karel Prach 《Acta theriologica》2014,59(2):317-324
We examined habitat preferences of the Southern Altai subspecies of gray marmots (Marmota baibacina baibacina) both at the small and large scale. Considerable differences in habitat use among the gray marmot (sub)species complex have been described; Marmota kastschenkoi possibly represents the only forest-dwelling Palearctic marmot. Our results show that habitat use in Southern Altai marmots is determined mainly by vegetation type. The Altai marmots preferred grasslands and shrublands and their distribution was limited to the alpine zone above timberline. Marmots clearly avoided woodlands, even the forest edges and forest-steppe areas with a tree cover greater than 10 %. Gray marmots occur rarely in habitats occupied by alpine pikas, whereas presence of ground squirrels had no effect on marmot distribution. Altai marmots preferred mesic habitats with permeable subsoil layers. Livestock grazing and human disturbance did not affect marmot occurrence. Habitat requirements of examined Altai subspecies M. baibacina baibacina differ from the forest-steppe M. kastschenkoi; nevertheless, the ecological factors to which the forest-dwelling species responds remain to be analyzed. A recent speciation process in gray marmot complex was followed by the evolution of ecological requirements resulting in adaptation to forest dwelling. 相似文献