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51.
Menacherry Sunil Paul M. Kočárek Martin Kacerova Tereza Kotíková Zora Kačer Petr Kodešová Radka 《Journal of Soils and Sediments》2022,22(2):522-535
Journal of Soils and Sediments - Dissipation of pharmaceutical compounds entered into the natural environment is an important process minimizing the adverse effects on the living organisms. The aim... 相似文献
52.
Tree-specific management practice related to individual tree physiological condition is necessary for higher quality and quantity in apple fruit production. Detection of apple flowering abundance based on analysis of HSL (hue, saturation, luminance) images was used to estimate the number of flower clusters (FC) of individual trees in a high density apple orchard. The image acquisition was performed with a still camera and an industrial color camera during the day and night. The FC estimation algorithm included HSL thresholding with parameter optimization. Three hypothetical, tree-specific management practices (sprayings) were assumed, using >25, >50 and >100 FC thresholds to carry out the practice. When an industrial camera was used for image acquisition during the daytime and hypothetical spraying was done by on/off criterion >100 FC per tree, 10 % incorrect executions were identified. Comparable FC counting performance was achieved by using a still camera or an industrial camera. 相似文献
53.
Metal pollution is a global problem which represents a growing threat to the environment. Because of bioaccumulation and negative effects of heavy metals, their bioavailability needs to be monitored. Many studies showed accumulation of metals in crayfish tissues as dose- and time-dependent without significant differences in tissue concentration levels comparing males and females. Muscles and exoskeleton were considered as specific for accumulation of mercury and nickel, respectively. Cadmium, zinc, copper, lead, and chromium accumulated mainly in hepatopancreas. By analyzing these specific tissues, it is possible to deduce the bioavailability and, by presumption, the level of environmental pollution by specific metals. However, in the case of zinc and copper, their utility is limited to assessing bioavailability because rapid depuration of these metals renders them less useful for long-term environmental monitoring programs. The literature reporting heavy metal impacts on freshwater crayfish, with reference to accumulation levels, is reviewed and summarized with respect to their suitability as bioindicators. Summarized published data from unpolluted or control localities can be used as referential values in crayfish, and consequently help with evaluation of monitored sites. 相似文献
54.
Mirjana D. Stojanović Dragi R. Stevanović Jelena V. Milojković Mirko S. Grubišić Deana A. Ileš 《Water, air, and soil pollution》2010,209(1-4):401-410
The aim of this article is the determination of uranium accumulation in plants tissue in shoots and roots of corn—maize (Zea mays), grown on two types of soils, pseudogley and chernozem, together with its phytotoxic effect on the plant growth and development. The soils was contaminated with different rates (10 to 1,000 mg U(VI) kg?1) of uranyl nitrate (UO2(NO3)2·6H2O). Vegetative tests performed with maize indicated uranium phytotoxic effect on plant height, yield, and germination of seeds. This effect was stronger on the plants grown on pseudogley in comparison with those grown on chernozem. Soil properties determined the tolerance and accumulation of U in plants. A linear dependence between the content of uranium in soil and in plants tissue, including maximal content of 1,000 mg U?kg?1, indicates that maize could be used for phytoremediation of uranium-contaminated soils. 相似文献
55.
K. Zemanová T. Picek J. Dušek K. Edwards H. Šantrůčková 《Water, air, and soil pollution》2010,207(1-4):39-48
Two horizontal constructed wetlands with subsurface flow (CWs) of different age were monitored in a 2-year study. One of the CWs was new, while the second one had been in operation for 5 years in the first year of study. Transformations of C, P, and N were measured in each CW in the substrate of the vegetated bed under both aerobic and anaerobic conditions, and their rates were compared. C was mineralized in both CWs under both aerobic and anaerobic conditions, but mineralization rates differed between the CWs; they were cca ten times higher in the established CW compared to the new CW. Dissolved reactive phosphorus (DRP) was immobilized under aerobic conditions but was mobilized under anaerobic conditions. DRP transformation was cca five times faster in the established CW. Nitrification occurred under aerobic conditions at similar rates in both CWs. NH4 + concentration decreased under both aerobic and anaerobic conditions, but there was large variability. The age of the CW affected C mineralization rates and DRP immobilization rates under aerobic conditions and mobilization rates under anaerobic conditions; they increased as the CWs maturated, while no effect of CW age was observed on nitrogen removal rates. 相似文献
56.
57.
Summary Wheat cultivars Salzmünder Bartweizen and Weique gave a similar pattern of reaction type when tested with 27 different races of stem rust and 17 races of leaf rust from Canada and Czechoslovakia. Both cultivars were resistant to all races of stem rust and most of the races of leaf rust. Genetic studies indicated that the two varieties have the same genes for rust resistance, with the genes for leaf and stem rust being closely linked.Transmission of the genes for rust resistance was irregular and appeared to be associated with meiotic irregularities in chromosome pairing. In all F2 populations which deviated significantly from a 3:1 ratio, a deficiency of resistant plants was noted. The greatest deficiency was in the F2 of crosses involving Salzmünder Bartweizen, of which the F1 hybrid also had the greatest meiotic irregularities.Chimeral plants, of which the longitudinal half of the leaf showed a resistant reaction and the other half a susceptible reaction, were observed in crosses with Salzmünder Bartweizen. 相似文献
58.
L. Maršálek 《Euphytica》1971,20(1):131-137
Summary In field trials conducted over three growth seasons I studied the differences in activities of the enzymes: polyphenoloxidase, ascorbateoxidase and peroxidase, with a heterotic single-cross hybrid of maize and its pollen-sterile analogue. Additional observations were made for differences between the single-cross hybrids and their parental lines. The samples (staminate spikelets) were taken at random just before and after tasselling. Significant differences could be established concerning the object set. Comparison of the self-pollinating line of maize with the pollen-sterile analogue revealed the down ward trend in peroxidase (P) activity with the pollen-sterile line; the upward trend in polyphenoloxidase (PPO) activity and the downward trend in ascorbateoxidase (A) activity were observed with the pollen-sterile line before tasselling. After tasselling, activity of PPO showed a downward and that of A an upward trend. The single-crospollen-sterile hybrid revealed, compared to the parental lines, an upward trend in its PPO and A activities before tasselling and a downward trend in the same enzymes after tasselling; while activity of P in this single-cross, pollen-sterile hybrid indicated the downward trend in general. Compared with the parental forms, the pollen-fertile hybrid of maize showed a trend towards lower activities of the studied enzymes for all seasons and periods under observation. Comparing results in the single-cross hybrids there was an indication of higher activities of PPO and A in the pollen-sterile analogue; whereas the same analogue revealed a lower activity of P before tasselling and higher value after tasselling. 相似文献
59.
Relationship between Frost Tolerance and Cold-Induced Resistance of Spring Barley, Meadow Fescue and Winter Oilseed Rape to Fungal Pathogens 总被引:1,自引:0,他引:1
Plants exposed to one stress factor may become more tolerant to another. Cold is the most often documented factor inducing plant resistance to pathogens. The aim of this work was to investigate whether resistance of spring barley and meadow fescue to Bipolaris sorokiniana and resistance of winter oilseed rape to Phoma lingam induced at 5 °C for 2, 4 or 6 weeks are associated with frost tolerance, water potential and soluble carbohydrate content. Cold‐acclimated plants of each species showed increased resistance to the studied pathogens. Barley, fescue and rape plants demonstrated higher frost tolerance after hardening, but only in the case of fescue a correlation between resistance to frost and resistance to B. sorokiniana was found. A significant decrease in the water potential of leaf cells was observed in cold‐acclimated barley and fescue. In these two species, water potential greatly affected resistance to B. sorokiniana. However, only in barley did accumulation of fructose, glucose and sucrose correlate as well with changes in water potential as with cold‐induced resistance to the pathogen. In the case of hardened rape, no correlation between the studied parameters was found. The results obtained indicated that the temperature of 5 °C used during cold acclimation was not favourable for hardening of this plant species. 相似文献
60.
Nives Ogrinc Tjaša Kanduč Bor Krajnc Urša Vilhar Primož Simončič Lixin Jin 《Journal of Soils and Sediments》2016,16(2):382-395