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Initial growth and ecophysiological response of six eucalyptus clones under different levels of water stress

100%

Pezzopane J. E. M., Tatagiba S. D., Penchel R. M., Reis E. F., Jesus Junior W. C.

Acta Physiologiae Plantarum

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2007

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tom 29

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nr 1 Suppl.

2

Steady-state and dynamic photosynthetic performance and nitrogen partitioning in the shade-demanding plant Panax notoginseng under different levels of growth irradiance

100%

Chen J.-W., Kuang S.-B., Long G.-Q., Meng Z.-G., Li L.-G., Chen Z.-J., Zhang G.-H., Yang S.-C.

Acta Physiologiae Plantarum

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2014

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tom 36

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nr 09

In this study, we examined steady-state and dynamic photosynthetic performance and leaf nitrogen (N) partitioning in the typical shade-demanding herb Panax notoginseng grown along a light gradient. Gas exchange on a leaf area basis was significantly reduced under low irradiance, with gas exchange on a leaf mass basis reaching a maximum value and then decreasing along the light gradient. Specific leaf area significantly increased with decreasing irradiance levels (P<0.001), whereas carboxylation efficiency was decreased (P<0.001). In addition, decreasing growth irradiance levels led to declines in maximum carboxylation rate (Vcmax) and maximum electron transport rate (Jmax), although Vcmax/ mass and Jmax/mass were relatively less affected than Vcmax/area and Jmax/area. Slow photosynthetic response to simulated sunflecks was observed under low levels of growth irradiance, with stomatal limitations only detected in leaves grown under low-light conditions. Chlorophyll content increased significantly with decreasing irradiance levels. N content on a leaf mass basis apparently increased, while N content on a leaf area basis markedly decreased. The fraction of leaf N allocated to light-harvesting components increased significantly with decreasing growth irradiance levels, whereas the fraction allocated to carboxylation and bioenergetics was significantly reduced. As an adaptation strategy to growth irradiance, we conclude that adjustments in specific leaf area may be more important than changes in leaf physiology and biochemistry in typical shade-demanding species such as P. notoginseng.

3

Effect of kappa-carrageenan on colour stability of model products with different levels of fat

84%

Dolatowski Z. J., Olszak M.

Electronic Journal of Polish Agricultural Universities. Series Food Science and Technology

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2007

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tom 10

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nr 1

4

Ecological education and its realization on different levels of educating an individual

84%

Winter B.

Acta Universitatis Wratislaviensis. Prace Botaniczne

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2001

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tom 79

227-233

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Influence of soil pH and suitability complex on potato yield at different levels of nitrogen fertilization

84%

Wierzejska-Bujakowska A.

Zeszyty Problemowe Postępów Nauk Rolniczych

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1998

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tom 456

In order to show the influence of soil pH and soil suitability complex on potato yield, long term experiments were carried out at different N doses (40 - 160 kg N ha⁻¹) and under different soil and climatic conditions (40 - 160 kg N ha⁻¹) in 1971 - 1990. Experiment results for each of the four soil suitability complexes were classified according to soil pH into following groups: pH in KCl 4.5; 4.6 - 5.5, 4.6 - 6.5 and 6.5. The optimum soil pH for potato production was found to dependent on the soil suitability complex.

6

Germination and seedling growth of Zea mays L. under different levels of sodium chloride stress

84%

Sozharajan R., Natarajan S.

International Letters of Natural Sciences

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2014

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tom 07

Salt stress is one of the most severe environmental factors that reduces and limits growth and development of plants. Abiotic stresses such as heavy metals, salinity, drought, temperature, UV-radiation, ozone causes drastic yield reduction in most of the crops. Especially salt stress affects around 20 of NaCl on germination and seedling growth of Zea mays L. Seeds of Zea mays were germinated in glass Petri- 100 × 15 mm diameter lined with blotting paper. Ten seeds were placed in each petri-dish. Petridishes were irrigated with 25, 50, 75, 100, 125, 150, 175 and 200 mM concentrations of NaCl. A control was moistened with ten milliliters of distilled water. The germination percentage, water absorption of the seeds, water uptake percentage and the growth parameters were observed. The results obtained showed that the inhibition of the germination percentage, germination rate, water uptake, growth and biomass accumulation of the seedlings were observed to decrease with increasing NaCl concentrations. At the highest level of stress both plumule and radical decreased significantly. The salt stress decreased seed germination, biomass and growth of maize seedlings due to ion toxicity, decrease osmotic potential and oxidative stress.

7

The effects of feeding with different levels of zinc and chromium on plasma thiobarbituric acid reactive substances and antioxidant enzymes in rats

84%

Esen Gursel F., Tekeli S. K.

Polish Journal of Veterinary Sciences

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2009

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tom 12

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nr 1

This study was designed to investigate the effects of supplementation and deficiency of dietary chromium (Cr), zinc (Zn) and combination of zinc and chromium on lipid peroxidation and antioxidant enzymes. A total of 84 male Wistar albino rats were fed rat chow containing different levels of Zn and Cr throughout the 84 days. Blood samples were collected for analysis of Thiobarbituric acid reactive substances (TBARS), Superoxide dismutase (SOD), Catalase (CAT) and Glutathione peroxidase (GSH-Px). TBARS concentrations in rats fed high-Cr diet, high-Zn and Cr diet and low-Zn diet were significantly higher than those determined in the control group (p ≤ 0.05). CAT activities in rats fed high-Cr diet were significantly higher than those observed in the control group. Cu-Zn SOD and GSH-Px activities were significantly higher in rats fed high-Cr diet, high-Zn and Cr diet, low-Zn diet, and low-Zn and Cr diet when compared to the activities found in the controls. These results suggest that trivalent chromium supplementation increase antioxidant enzymes by enhancement of lipid peroxidation, but Zn supplementation does not have any effect on lipid peroxidation. Also Zn deficiency resulted in increased lipid peroxidation, SOD and GSH-Px activities because of the oxidative stress caused by zinc deficiency.

8

Anatomy of abscission zone of Betula pendula (Roth.) leaves from trees growing under different levels of pollution

84%

Dobrowolska I., Kurczynska E. U., Dmuchowski W.

Dendrobiology

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2001

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tom 46

A study was carried out on the leaf abscission zone from birch trees growing on polluted sites (two) and a non-polluted site (one). Samples for anatomical investigation were collected from six trees on each site, during three succeeding vegetation seasons. It was observed that in trees growing at the polluted sites: 1) maturation of the abscission zone was faster, 2) the protective layer was thinner and 3) the formation of leaf scar periderm was delayed in comparison with trees from the non-polluted site. The results obtained suggest that environmental pollution influences the formation of the abscission zone and the protection of the leaf scar.

9

Efficacy of different levels of Escherichia coli phytase in hens fed maize-soyabean meal based diets with a decreased non-phytase phosphorus content

67%

Kozlowski K., Jeroch H.

Journal of Animal and Feed Sciences

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2011

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tom 20

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nr 2

The aim of this experiment was to determine the efficacy of different inclusion levels of new type phytase (ECP) synthesized by Escherichia coli and expressed in Pichia pastoris yeast (Optiphos) in maize-soyabean meal based diets on egg quality and the laying performance of laying hens aged from 20 to 44 weeks. Two hundred and twenty Lohmann Brown hens were randomly assigned to five treatments with 44 replicates each, and were kept individually in cages. The control diet (C) contained 2.5 g non-phytate phosphorus (NPP) and 35.5 g Ca/kg feed, and the experimental diets contained 1.3 g NPP and 33.0 g Ca/kg feed. The deficient diet (D) was offered without any addition of phytase, while the other treatments involved different levels of this enzyme: 125, 250 and 500 FTU/kg feed (treatments ECP125, ECP250 and ECP500, respectively). Compared with the deficient diet, phytase supplementation significantly affected the performance of hens over the entire experimental period (number of eggs laid, egg mass and FCR), and egg quality parameters: egg yolk colour (significantly in week 24 of the laying period) and shell thickness (significantly in week 12 of the laying period). The results of the present study indicate that the supplementation of diets for laying hens with ECP improved performance parameters. The NPP content of layer diets based on maize meal and soyabean meal can be reduced by 1.2 g/kg provided that the diets are supplemented with ECP at 125-250 FTU per kg diet.

10

Efficacy of different levels of Escherichia coli phytase in broiler diets with a reduced P content

67%

Kozlowski K., Jankowski J., Jeroch H.

Polish Journal of Veterinary Sciences

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2010

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tom 13

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nr 3

11

Yield of winter durum wheat (Triticum durum Desf.) lines in condition of different protection level of plants

67%

Rachon L., Szumilo G.

Acta Scientiarum Polonorum. Agricultura

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2009

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tom 08

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nr 3

The paper deals with evaluating the yield and yield structure elements of winter durum wheat lines (Triticum durum Desf.) under conditions of varied levels of chemical protection. The field experiments were carried out in 2006-2008 on the Experimental Farm Felin, University of Life Sciences, Lublin. Examinations involved 3 lines of durum wheat (STH 716, 717, 725) achieved from Plant Breeding Station in Strzelce as well as common wheat Tonacja cv. for comparison. The second factor consisted of 2 levels of chemical protection: I – minimum (seed dressing Oxafun T 75 DS/WS and herbicide Chwastox Trio 540 SL); II – complex (seed dressing, herbicides Puma Uniwersal 069 EW and Chwastox Trio 540 SL, fungicide Alert 375 SC, growth regulator Stabilan 750 SL and insecticide Decis 2,5 EC). Obtained results allowed for concluding that when comparing with minimum protection, the increase in wheat grain yields by 1.08 t·ha⁻¹ was recorded on complex-protected treatments, regardless of compared lines and varieties. Lower yield of durum wheat as compared to common wheat resulted first of all from lower spike density per area unit. A positive influence of chemical protection on spike number and grain number per spike was observed. Durum wheat lines were characterized by high grain vitreousness.

12

Response of Shami goats and kids to variable levels of soyabean or sunflower oils in diets

67%

Titi H. H., Hasan Y. L., Al-Ismail K., Zakaria H., Tabbaa M. J., Abdullah A. Y., Obeidat B. S.

Journal of Animal and Feed Sciences

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2011

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tom 20

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nr 4

13

Production indices and carcass fat quality in fatteners fed mixtures containing different levels of rapeseed cake

67%

Frankiewicz A., Bestynska A., Przybecka I., Mroczyk W., Lyczynski A., Czyzak-Runowska G.

Polish Journal of Natural Sciences. Supplement

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2006

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tom 03

285-291

14

The effects of different levels of protein, fat and carbohydrates in model diets on some physiological parameters of mice

67%

Kolataj A., Broniek S., Bujko J., Lach H., Srebro Z., Sura P.

Acta Biologica Cracoviensia. Series Zoologia

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2002

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tom 44

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