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Chlorophyll a fluorescence parameters (Fv/Fm, Fv/F₀ and Fvj) were used in testing wild oat (Avena fatua L.) resistance/susceptibility to fluazifop and quizalofop. Measurements of the selected fluorescence parameters were carried out at two terms: 24 and 48 hours after spraying resistant and susceptible biotypes of weeds with field doses of herbicides: Fusilade Forte 150EC and Targa Super 05EC. The obtained results indicate, that chlorophyll a fluorescence differed between resistant and susceptible biotypes. From all tested parameters Fvj is adequate for indicating wild oat resistance level to fluazifop and quizalofop.
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Bioherbicydy i alleloherbicydy w walce z chwastami

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Konkurencja między roślinami tego samego gatunku, jak i różnymi gatunkami, sąsiadującymi ze sobą, to powszechne i ważne oddziaływania w przyrodzie. Tę konkurencję określa się mianem allelopatii. Jest to w ostatnich latach coraz bardziej poznawane zjawisko, w które zaangażowane są metabolity wtórne, czyli różnego rodzaju związki chemiczne, specyficzne dla poszczególnych gatunków roślin. Charakter interakcji allelopatycznych może sprzyjać rozwojowi sąsiednich roślin, częściej jest to działanie hamujące wzrost i rozwój sąsiadów. Wykorzystanie allelopatii ma szczególne znaczenie w rolnictwie ekologicznym.
In the years 2003-2004 two experiments: laboratory and field, were carried out to detect the level of wild oat herbicide resistance. Weeds were collected from fields in south-eastern Poland, on the basis of survey conducted between farmers who have problems with wild oat herbicidal fighting. Two herbicides were tested: fenoxaprop- P-ethyl and diclofop methyl, both ACC-ase inhibitors. The laboratory test was established by modified Letouze et al. (1997) method. After 6-day growth on each herbicide water solution, the number of alive wild oat seedlings was assesed. In the field experiment plants in 3-5 leaf stage were sprayed with field dose of each herbicide. Two weeks after spraying the percentage of plants damage and in July the percentage of flowering plants were assesed. The wild oat plants that survive in laboratory test in ≥50% and plants that flowered in ≥50% in field conditions were recognized as resistant. On that basis wild oat resistace to fenoxaprop-P-ethyl and to diclofop methyl was stated on 17% and 28% fields from overall number of 18 fields, respectively.
The present work is a continuation of studies on the use of ion-exchanging properties of smectite raw material from Męcinka mine to the recovery of chromium from waste water. In this work the smectite ion-exchange column was used for removal of other heavy metals: Zn (II), Cd (II),Pb(II).Theeffect of ion-exchangeZn (II),Cd (II),Pb(II)from model solutions prepared out of nitrate salts of these metals was examined under dynamic conditions. The efficiency of ion-exchange column with smectite bed was determined by measuring in the column efflux till the moment when the concentration of metals in efflux is equal to concentration in influx. For measurement of concentration of metals the voltamperometric method was used. The ion-exchanging column was determined by stating the following parameters: sorption capacity of exchanger, volume of solution till the moment of column breakthrough (Vmax) and column dynamics, which meansthe relative concentration of metal ions c/c0 in theefflux as a function of efflux volume. Out of the model waste water containing three heavy metals, the best eliminated is Pb (II) and subsequently Zn (II). The efflux volume classified to the 1st and 2nd category of water cleanness amounts to about 1/3 Vmax. Worse results are observed for ions Cd (II), which have the least ion exchange ability. The obtained results of studies on removal of ions of heavy metals: Zn (II), Cd (II), Pb (II) out of model waste water confirm, similar to the Cr (III) studies, the possibility of application of the raw smectite adsorbent as the column packing within the process of removal of heavy metals.
This greenhouse experiment evaluated the response of hoary alyssum plants, up to the rosette phase, to different levels of UV-B radiation. The experiment was carried out in the chambers, equipped with UV-B lamps, emitting biologically effective UV-B radiation of 0 (control), 4, 6 or 8 kJ. As a result, specific traits of the plants such as: leaf number, lamina length, leaf area, specific leaf weight, relative chlorophyll content and shoot biomass were unaffected by any of the UV-B treatments. Significant reductions in the share of large leaves, leaf stalk length and root biomass were noted for plants growing under 8 kJ UV-BBE.
Our study aims at statistical modelling of changes in the level of air pollution in the area of Szczawno Zdrój in Poland throughout the period of 1989-2003, which was marked by a decrease in coal production as well as by rapid increases in traffic intensity. Sulphur dioxide and the nitrogen dioxide were chosen as pollution indicators. Changes of the averaged concentrations across years are modelled by 5 regression models: linear, logarithmic, 2nd degree polynomial, 3rd degree polynomial and 4th degree polynomial. Changes in average yearly concentrations of pollutants during the 1980s and 1990s indicate considerable improvement of air quality regarding sulphur dioxide and nitrogen dioxide contents. A noticeable tendency toward a decrease in air pollution results from limiting of sulphur dioxide emission sources, which translates into liquidation of especially burdensome industrial plants, installation of devices for sulphur removal from fumes, and substantial reduction of air pollution coming from the Czech Republic and Germany.
The possibility of the chlorophyll α fluorescence test (maximum quantum efficiency of PS2 photochemistry - Fv/Fm parameter) in the early detection of wild oat resistance to fenoxaprop-P-ethyl and diclofop methyl was examined. Measurements were taken at two terms: 24 and 48 hours from spraying the resistant nad susceptible biotypes of weed with field doses of herbicides: Puma Uniwersal 069 EW and Illoxan 36 EC. The obtained results indicate, that chlorophyll fluorescence test can not be used for an early detection of wild oat (Avena fatua L.) resistance to tested herbicides.
Plants of small-seeded lentil plants (cv. Obrazcov) and that of coarse-seeded (cv. Izka) were subjected to soil drought in pot experiment in three developmental phases: 1) second offshoot — vegetative phase, 2) full blooming, 3) advanced development of pods, and its direct and consequent effect on the growth of plant height, of the dry weight of shoots and roots, and on seed-yield structure components were determined. The seed yield was most strongly limited after drought during blooming phase, especially in cultivar Izka, to less extent — after drought in vegetative phase, but in the phase of advanced pod development it did not cause any significant effects. The results obtained show that the response of compared lentil cultivars is differentiated and that the more significant reduction of seed yield is caused by drought in the blooming phase.
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