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61.
Vesely Tomas Neuberg Marek Trakal Lukas Szakova Jiřina Tlustoa Pavel 《Water, air, and soil pollution》2012,223(4):1847-1859
The effects of one of the most toxic heavy metals, lead (Pb), applied in two different concentrations and combined with chelate
application were investigated on the water macrophyte (Pistia stratiotes L.) physiology. The influences were observed by the chlorophyll and free amino acid content determination. Also the lead
accumulation in macrophyte biomass was investigated to assess the potential efficiency of this plant for rhizofiltration of
highly Pb-polluted water. Na EDTA and Na citrate were used as chelates and Pb(NO3)2 as lead supplement. The application of organic chelates simulated conditions of an induced phytoextraction process. Statistical
analyses were performed as a one-way ANOVA with a subsequent Tukey HSD test at a level of P < 0.05. Pb contents in both root and leaf tissues gradually increased with increasing Pb concentrations in the nutrient solution.
More lead was accumulated in leaves than in roots within all treatments. The total chlorophyll content decreased with increased
Pb concentration and with a higher content of chelates. The chelate addition increased the total amino acid content in leaves
but decreased the total amino acid content in roots. The addition of lead with chelates decreased the dry biomass weight.
However, water macrophyte showed extremely high lead accumulation in biomass in the short term (up to 8 days) and this accumulation
potential could be used for relatively fast and effective decrease of high concentration of this risk element in contaminated
water or sewage. 相似文献
62.
Sera from 335 farmed fallow deer (Dama dama) at the breeding station in Kosewo Górne in the Mazurian Lake District, North-East Poland, were investigated for the presence of antibodies against Neospora caninum. The distribution of age groups was as follow: >4 years - 154 animals; 2 years - 76 animals; 1 year - 105 animals. Ten sera with the optical density exceeding 0.159 absorbance units (i.e., cut-off value) in ELISA test were also analyzed by Western blot. Western blot analysis revealed seroreactivity against immunodominant N. caninum antigens of 37, 25, and 16kDa; however, in some sera additional bands were also visible. This is the first screening studies for antibodies against N. caninum in farmed fallow deer in Poland, in the region where neosporosis was confirmed in cattle and in farmed and free-ranging European red deer (Cervus elaphus). 相似文献
63.
Rebecca Ibach Marek Gnatowski Grace Sun Jessie Glaeser Mathew Leung John Haight 《Wood material science & engineering》2018,13(2):81-96
The flexural properties of wood–plastic composite (WPC) deck boards exposed to 9.5 years of environmental decay in Hilo, Hawaii, were compared to samples exposed to moisture and decay fungi for 12 weeks in the laboratory, to establish a correlation between sample flexural properties and calculated void volume. Specimens were tested for flexural strength and modulus, both wet and dry, at 23°C and 52°C. Some specimens degenerated to only 15% of original flexural strength. UV radiation had no impact on flexural properties of field-exposed boards; loss occurred mainly on the side opposite to the sun-exposed surface. The mechanism of the aging process on colonization of WPC by fungi was examined and is consistent with development of slow crack growth in the polyethylene matrix combined with wood decay by fungi. Wood particle decay, moisture, and elevated temperature were the major factors causing composite degradation, indicated by accumulation of voids and a severe decrease in flexural properties. To simulate long-term field impact (including decay) on WPC flexural properties in the laboratory, conditioning of specimens in hot water for an extended period of time is required. Exposure to water (70°C/5 days) was adequate for simulating long-term composite exposure in Hawaii of 4?×?15?×?86 mm3 specimens. 相似文献
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65.
Assessment of the impact of climate change on the latency period of leaf rust on triticale in Poland
Andrzej Wójtowicz Marek Wójtowicz Roland Sigvald Bartosz Czernecki Henryk Ratajkiewicz Agnieszka Łacka 《Acta Agriculturae Scandinavica, Section B - Plant Soil Science》2020,70(3):195-207
ABSTRACTDisease development in plants is strongly dependent on weather conditions, with temperature playing a particularly significant role by influencing latency period duration. Using two models describing the relationship between latency period and temperature, we performed simulations aimed at predicting changes in the latency period of leaf rust (Puccina recondita f. sp. tritici) on triticale in response to expected climate change. The simulations were based on meteorological data recorded in the period 1986–2005 at locations representing 16 provinces in Poland and based on values obtained after transformation of the observed data to reflect temperature changes under four scenarios (RCP2.6, RCP4.5, RCP6.0 and RCP8.5) according to the giss_e2_r climate model. In all scenarios, the results for the two triticale cultivars studied, Witon (vulnerable to P. recondita) and Gniewko (less susceptible), showed a threat of faster development (shorter leaf rust latency period) on triticale triggered by climate change in south-east and south-central Poland than in other regions. The results also showed an increased probability of future regional diversification of leaf rust latency period duration on vulnerable triticale cultivars, opportunities for earlier start of leaf rust epidemics on triticale in Poland and an increase in ?nal disease severity in comparison with 1986–2005. 相似文献
66.
Masternak Katarzyna Oko Sylwia Kamola Marek Ociepa Tomasz Nucia Aleksandra Kowalczyk Krzysztof 《European Journal of Forest Research》2022,141(4):617-628
European Journal of Forest Research - Increasing areas of gradation, making it difficult or impossible to perform restorations and forestations, and as causing tree crown damage, result in the need... 相似文献
67.
Greenhouse production of floricultural crops uses soilless substrates, which have limited amounts of plant-available silicon (Si) compared to mineral soils. The inclusion of Si supplements in greenhouse production has proven beneficial for several crops. The goal of this study was to evaluate the incorporation of Si supplements for improved flower quality of greenhouse-produced zinnia (Zinnia elegans). In the first study, quantitative horticultural traits and leaf Si, macronutrient and micronutrient concentrations were compared between Si-treated and control plants. The Si supplements evaluated were rice husk ash substrate incorporation, hydrous potassium silicate (KSiO3) substrate incorporation or weekly KSiO3 substrate drenches, and weekly sodium silicate (NaSiO3) foliar sprays. Several horticultural traits differed in Si-treated plants. The flower and stem diameters were larger in plants supplemented with at least one rate of each Si supplement. Reduced plant heights and 3–5-day delays in anthesis occurred in plants supplemented with weekly KSiO3 drenches. Leaf Si concentrations were 1.2–3.3-fold higher in Si-supplemented plants, while the macronutrients, N, S, Mg, and Ca, were lower and K was higher only in KSiO3-supplemented plants. In a second study, the effects of weekly KSiO3 drenches and weekly NaSiO3 foliar sprays on the leaf resistance of zinnia plants were evaluated. Only the NaSiO3 foliar sprays moderately increased leaf resistances. While not supporting an active role for Si in reducing transpiration, NaSiO3 foliar sprays may form antitranspirant film that increases leaf resistance. Thus, the beneficial effects of Si supplementation on greenhouse-produced zinnia depend on the form and rate of Si used. 相似文献
68.
Martin Kocour Otomar Linhart David Gela Marek Rodina 《Journal of the World Aquaculture Society》2005,36(1):103-113
The results of a 4-yr study focused on comparing growth performance in all-female and mixed-sex populations of common carp are presented. All-female and mixed-sex populations of purebred Northern mirror carp (M72) and scaly crossbreds of female Ropsha (ROP) and male/neomale M72 carp (ROP × M72) were used for this experiment. Average weight and survival after each growing season and slaughtering value after the third and fourth year of the study were measured. While after 8 wk of rearing no differences between all-female and mixed-sex populations were found, the 1-yr-old all-female mirror carp population (M72) gained 29.7% more weight ( P < 0.0001) than the mixed-sex (68.5:± 15.8 g against 52.8:± 13.9 g; meant S.D.) population. After the second, third and fourth year of rearing, live weight was 9.5% ( P = 0.0062) and 6.8% ( P = 0.0229) and insignificantly 5.1 % higher, respectively, in the all-female population. There was no significant difference, even after the fourth growing season, in live weight between all-females and bisexual scaly crossbreds (2,192 g± 478.3 and 2,206 g± 484.5, respectively). The percentage of the main edible parts (processed body, filleting yield) was significantly higher in both mirror and scaly, all-female populations at 3 yr of age but not significantly different in 4-yr-old fish. No distinct differences in survival and body shape of all-female and bisexual populations were found. The potential of all-female populations for commercial production is discussed. 相似文献
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