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101.
102.
Szymon Jastrzębowski Joanna Ukalska Władysław Kantorowicz Marcin Klisz Tomasz Wojda Małgorzata Sułkowska 《European Journal of Forest Research》2017,136(3):471-479
The aim of this study was to determine the efficiency of methods for the artificial scarification of black locust seeds based on the influence of the air and liquid nitrogen temperatures. Three populations were selected for the analyses: a managed tree stand, a selected seed stand and a seed orchard. Samples of 200 seeds (4 × 50) were randomly selected. Before scarification, the seeds were stored at ?70 °C for 24 h. Nine different scarification treatments were evaluated. To calculate the germination capacity and the dynamics of germination, observations were made on days 3, 5, 7, 10 and 14 after treatment. For statistical analyses, we used repeated measures analysis of variance. The obtained results indicated that the highest scarification efficiency for black locust seeds occurred in the treatment in liquid nitrogen and in an air temperature range of 85–90 °C. The provenance of seeds had a significant effect on the dynamics of germination. Thermal methods and the use of liquid nitrogen can be alternatives to the labour intensive methods of cutting the seeds or using measures that require specialised equipment. 相似文献
103.
Justyna Połedniok Joanna Orzeł Justyna Gałeczka Rozalia Czoik 《Communications in Soil Science and Plant Analysis》2017,48(8):936-942
A simple and very sensitive spectrophotometric method determining microgram quantities of gallium (Ga) has been developed. The method is based on the complex of Ga(III) with Chrome Azurol S (CAS) in the presence of benzyldodecyldimethylammonium bromide (ST) and polyoxyethylenesorbitan monopalmitate (Tween 40). The complex forms in weakly acid solution (pH 3.8) and shows the absorption maximum at 627 nm. The molar absorptivity (ε) of this system is 1.87 × 105 L mol?1 cm?1, and it is clearly higher than ε of other spectrophotometric methods of gallium determination. The detection and quantification limits (LOD, LOQ) are 7.6 × 10–3 and 0.023 µg mL?1, respectively. Beer‘s law is obeyed in the range from 0.02 to 0.60 µg mL?1 of Ga. The precision and accuracy are good. This first spectrophotometric method of Ga(III) determination in the four-component system has been successfully applied for the analysis of mushrooms and grasses with low content of gallium. 相似文献
104.
Paśko P Zagrodzki P Bartoń H Chłopicka J Gorinstein S 《Plant foods for human nutrition (Dordrecht, Netherlands)》2010,65(4):333-338
The effect of Chenopodium quinoa seeds on lipid profile, glucose level, protein metabolism and selected essential elements (Na, K, Ca, Mg) level was determined
in high—fructose fed male Wistar rats. Fructose decreased significantly LDL [42%, p < 0.01] and activity of alkaline phosphatase [20%, p < 0.05], and increased triglycerides level [86%, p < 0.01]. The analysis of blood of rats fed quinoa indicated, that these seeds effectively reduced serum total cholesterol
[26%, p < 0.05], LDL [57%, p < 0.008] and triglycerides [11%, p < 0.05] when compared to the control group. Quinoa seeds also significantly reduced the level of glucose [10%, p < 0.01] and plasma total protein level [16%, p < 0.001]. Fructose significantly decreased HDL [15%, p < 0.05] level in control group but when the quinoa seeds were added into the diet the decrease of HDL level was inhibited.
Quinoa seeds did not prevent any adverse effect of increasing triglyceride level caused by fructose. It was shown in this
study that quinoa seeds can reduce most of the adverse effects exerted by fructose on lipid profile and glucose level. 相似文献
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107.
Veronika??i?a?ová Joanna?Kaczmarek Stephen?E.?Strelkov Jan?Kazda Wolfgang?Lueders Pavel?Rysanek Victor?Manolii Malgorzata?JedryczkaEmail author 《European journal of plant pathology / European Foundation for Plant Pathology》2016,145(3):559-572
Winter oilseed rape (Brassica napus) is an important crop in the Czech Republic and Poland. Clubroot disease caused by the pathogen Plasmodiophora brassicae is a serious and still-growing problem for oilseed rape growers in both countries. The aim of this study was to evaluate the pathotype composition of P. brassicae populations from the Czech Republic and Poland, according to the three evaluation systems, and to determine soil inoculum loads for representative fields via traditional end-point PCR as well as quantitative PCR analysis. There were considerable differences between the populations of P. brassicae from both countries, and the number of pathotypes varied depending on the evaluation system and the threshold used to distinguish susceptible vs. resistant plant reactions. This is the first study comparing the effect of different thresholds. Using an index of disease (ID) of 25 % to distinguish susceptible vs. resistant reactions, there was a total of seven pathotypes identified based on the differentials of Williams, five with the system of Somé et al., and 18 with the European Clubroot Differential (ECD) set. However, based on a threshold of 50 %, there were nine pathotypes according to the evaluation system by Williams, four based on the differentials of Somé et al., and 15 with the ECD set. Changing of the thresholds led to the reclassification of some pathotypes. Several pathotypes were common in both countries. High amounts of pathogen DNA were found in many of the field soils analysed by quantitative PCR. There was a weak correlation between soil pH and infestation of P. brassicae for the Polish soils. 相似文献
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109.
Joanna Nowak Marian Saniewski R. M. Rudnicki 《The Journal of Horticultural Science and Biotechnology》2013,88(4):383-390
Changes in the content of carbohydrates and in the activity of hydrolytic enzymes were studied in hyacinth bulbs exposed to low temperatures. It was found that the amount of insoluble carbohydrate initially present in the scales and buds of hyacinth bulbs decreased greatly after a prolonged period of low temperature treatment. This decrease was greater in rooted bulbs, held at a low temperature for 63 days in natural conditions, than in unrooted bulbs stored in a refrigerator for the same period. At the same time the levels of soluble mono- and oligosaccharides, and of soluble starch, increased in the scales and buds of chilled bulbs. These changes in sugar level were found to be correlated with changes in the activity of certain hydrolytic enzymes. The activity of these enzymes was higher in rooted bulbs than in those which had not rooted before treatment. The activity of hydrolytic enzymes was found to be considerably higher in the flower buds than in the scales. 相似文献
110.
Joanna Zając Ivo A. Van Der Lans 《The Journal of Horticultural Science and Biotechnology》2013,88(6):22-27
SummaryThe goals of this study were to make an inventory of recent and ongoing fruit and fruit product innovations, to assess what novelty or improvement they offer, and whether consumers could identify and/or recognise them. Researchers from 11 European countries submitted 386 examples of fruit and fruit product innovations. The list of innovations obtained has been coded, categorised, sorted, and reduced in subsequent stages. First, the examples received were categorised according to the Oslo Manual definitions. Second, product and marketing innovations were selected, as they are the only ones that were likely to be recognised by consumers. Next, analysis revealed that the novelties these innovations offered related to Convenience, Health, Differentiation, Target Group, Information, Sensory Characteristics, In Home and/or Out of Home Quality. Some innovations offered only one novel aspect, whereas others offered multiple aspects. Interrelationships between novel aspects are discussed for those innovations that offered a combination of aspects. 相似文献