Template-Type: ReDIF-Article 1.0 Author-Name: J.F.T. Ganança Author-Workplace-Name: Centre of Macaronesian Studies, University of Madeira, Portugal Author-Name: I. Abreu Author-Workplace-Name: Centre of Macaronesian Studies, University of Madeira, Portugal Author-Name: N.F. Sousa Author-Workplace-Name: Centre of Macaronesian Studies, University of Madeira, Portugal Author-Name: R.F. Paz Author-Workplace-Name: Centre of Macaronesian Studies, University of Madeira, Portugal Author-Name: P. Caldeira Author-Workplace-Name: Centre of Macaronesian Studies, University of Madeira, Portugal Author-Name: T.M.M. Dos Santos Author-Workplace-Name: Centre of Macaronesian Studies, University of Madeira, Portugal Author-Name: G. Costa Author-Workplace-Name: Centre of Macaronesian Studies, University of Madeira, Portugal Author-Name: J.J. Slaski Author-Workplace-Name: Environmental Technologies, Alberta Research Council, Vegreville, Alberta, Canada Author-Name: M.Â.A. Pinheiro De Carvalho Author-Workplace-Name: Centre of Macaronesian Studies, University of Madeira, Portugal Title: Soil conditions and evolution of aluminium resistance among cultivated and wild plant species on the Island of Madeira Abstract: Soil samples collected from different soil formations throughout the Island of Madeira were analysed for pH, aluminium (Al) and organic matter content. On average, the Madeira soils appeared to be acid with a mean pH of 5.01, containing 0.79 cmol/kg of ionic Al and 3.02% organic matter, which may create favourable conditions for the development of Al resistance among plant species inhabiting the island. Six plant species were evaluated for their resistance to Al using the erichrome cyanine R tests: three agricultural species including wheat (Triticum aestivum L. and Triticum turgidum L.) and corn (Zea mays L.) and three wild species from the genus Sinapidendron. Profound differences in adaptation to local edaphic parameters (Al content, acidity, organic matter, altitude) between cultivated and wild species were observed. Comparison of the distribution patterns of the cultivated and wild species on the island may indicate that the anthropogenic activities played a pivotal role in the development of enhanced Al resistance among the cultivated species, while edaphic conditions seem to be a secondary factor. Keywords: aluminium resistance, corn, Sinapidendron, Madeira, soil acidity, wheat Journal: Plant, Soil and Environment Pages: 239-246 Volume: 53 Issue: 6 Year: 2007 DOI: 10.17221/2218-PSE File-URL: http://pse.agriculturejournals.cz/doi/10.17221/2218-PSE.html File-Format: text/html X-File-Ref: http://agriculturejournals.cz/RePEc/caa/references/pse-200706-0001.txt Handle: RePEc:caa:jnlpse:v:53:y:2007:i:6:id:2218-PSE Template-Type: ReDIF-Article 1.0 Author-Name: K. Zarzecka Author-Workplace-Name: Faculty of Agriculture, University of Podlasie, Siedlce, Poland Author-Name: M. Gugała Author-Workplace-Name: Faculty of Agriculture, University of Podlasie, Siedlce, Poland Title: Changes in the content of glycoalkaloids in potato tubers according to soil tillage and weed control methods Abstract: A field experiment was carried out in the fields of the Experimental Farm in Zawady owned by the University of Podlasie in Siedlce. An influence of soil tillage methods and herbicides application on the content of glycoalkaloids in edible potato tubers of the Viking cultivar was studied. The results obtained indicated that the content of glycoalkaloids in non-peeled tubers significantly depended on the method of soil tillage and weed control as well as on the research year, whereas in peeled tubers the content significantly depended only on the weather conditions in the growing season. The content of glycoalkaloids in the tubers subjected to the initial treatment (peeling) decreased to 46.81-55.3%, compared to the level of glycoalkaloids before peeling. Keywords: potato, glycoalkaloids, soil tillage methods, herbicides Journal: Plant, Soil and Environment Pages: 247-251 Volume: 53 Issue: 6 Year: 2007 DOI: 10.17221/2221-PSE File-URL: http://pse.agriculturejournals.cz/doi/10.17221/2221-PSE.html File-Format: text/html X-File-Ref: http://agriculturejournals.cz/RePEc/caa/references/pse-200706-0002.txt Handle: RePEc:caa:jnlpse:v:53:y:2007:i:6:id:2221-PSE Template-Type: ReDIF-Article 1.0 Author-Name: K. Hamouz Author-Workplace-Name: Faculty of Agrobiology, Food and Natural Resources, Czech University of Life Sciences Prague, Czech Republic Author-Name: J. Lachman Author-Workplace-Name: Faculty of Agrobiology, Food and Natural Resources, Czech University of Life Sciences Prague, Czech Republic Author-Name: P. Dvořák Author-Workplace-Name: Faculty of Agrobiology, Food and Natural Resources, Czech University of Life Sciences Prague, Czech Republic Author-Name: O. Dušková Author-Workplace-Name: Faculty of Agrobiology, Food and Natural Resources, Czech University of Life Sciences Prague, Czech Republic Author-Name: M. Čížek Author-Workplace-Name: Potato Research Institute, Havlíčkův Brod, Czech Republic Title: Effect of conditions of locality, variety and fertilization on the content of ascorbic acid in potato tubers Abstract: The effect of conditions of locality, variety and fertilization on ascorbic acid (AA) content in potato tubers was investigated in precise field trials in 2004 and 2005 in the Czech Republic. From four localities and in the two-year average the highest AA was statistically determined in the locality of Prerov nad Labem with the highest average temperature values during both experimental years (by 6.7 to 11.5% higher in comparison to other localities). Similarly, the effect of variety was also very significant; Marabel variety had the highest AA content (207.2 mg/kg fw) and exceeded other seven varieties by 15-49%. A negative effect on AA content in tubers was observed in the case of an increased intensity of N fertilization (at 180 kg N/ha AA decrease was lower by 6.1% compared to doses 100 kg N/ha). On the contrary, a favourable effect was determined at increased levels of potassium and magnesium fertilization (at 166 kg K/ha and 60 kg Mg/ha AA increase was by 6.2% higher compared to the levels of 108 kg K/ha and 30 kg Mg/ha). Keywords: ascorbic acid, potatoes, locality, variety, fertilization Journal: Plant, Soil and Environment Pages: 252-257 Volume: 53 Issue: 6 Year: 2007 DOI: 10.17221/2217-PSE File-URL: http://pse.agriculturejournals.cz/doi/10.17221/2217-PSE.html File-Format: text/html X-File-Ref: http://agriculturejournals.cz/RePEc/caa/references/pse-200706-0003.txt Handle: RePEc:caa:jnlpse:v:53:y:2007:i:6:id:2217-PSE Template-Type: ReDIF-Article 1.0 Author-Name: H. Laser Author-Workplace-Name: Institute of Plant Production and Plant Breeding II, Justus-Liebig-University of Giessen, Germany Title: Effects of liming and nitrogen application on the trace element concentrations of pastures in low mountain range Abstract: In less intensively managed grassland, the micronutrient concentrations in herbage are apparently more likely to be in levels between barely sufficient and deficient than to be excessively high. Insufficient amounts of selenium, copper, manganese, and zinc cause physiological disorders in ruminants. Three identical field trials on pastures with different soil pH and organic matter content were established to assess the effect of liming and nitrogen fertilization on the micronutrient concentrations in herbage. In the case of selenium the effect of a selenate application on the Se concentration in plants was also tested. The effect of liming on the micronutrient concentrations was not always consistent with initial hypotheses. Only Mn and - to a smaller extent - Zn concentrations changed markedly with an increasing soil pH (P < 0.01). Marked differences between concentrations in primary growths and secondary growths were evident for all trace elements. The effect of added nitrogen was negligible. Se concentrations in the plant tissue in plots without selenate application averaged 21.3 μg Se/kg dm in 2002 (standard error SE = 18.63) and 48.7 μg Se/kg dm in 2003 (SE = 38.97). Sufficient Se concentrations (> 100 μg Se/kg dm) were only found in herbage fertilized with selenate. Mn concentrations met the requirements for ruminants in most cases (mean Mn concentration in 2002 = 104.2 mg Mn/kg dm; standard error SE = 62.76; mean Mn concentration in 2003 = 67.5 mg Mn/kg dm; SE = 35.91). The average Zn concentrations were 33.5 mg Zn/kg dm in 2002 (SE = 6.46) and 34.0 mg Zn/kg dm in 2003 (SE = 7.52). The average Cu concentrations were 10.5 mg Cu/kg dm in 2002 (SE = 1.24) and 9.9 mg Cu/kg dm in 2003 (SE = 1.93). Therefore, 41.7% of the measured values for Zn and 31.3% of Cu concentrations remained under the recommended levels of > 30 mg Zn/kg dm and > 10 mg Cu/kg dm. Keywords: copper, manganese, selenium, zinc, animal nutrition, pastures Journal: Plant, Soil and Environment Pages: 258-266 Volume: 53 Issue: 6 Year: 2007 DOI: 10.17221/2222-PSE File-URL: http://pse.agriculturejournals.cz/doi/10.17221/2222-PSE.html File-Format: text/html X-File-Ref: http://agriculturejournals.cz/RePEc/caa/references/pse-200706-0004.txt Handle: RePEc:caa:jnlpse:v:53:y:2007:i:6:id:2222-PSE Template-Type: ReDIF-Article 1.0 Author-Name: M. Kozak Author-Workplace-Name: Department of Biometry, Warsaw Agricultural University, Warsaw, Poland Author-Name: M.S. Kang Author-Workplace-Name: Schoolof Plant, Environmental and Soil Sciences, Louisiana State University Agricultural Center, Baton Rouge, L.A., USA Author-Name: M. Stępień Author-Workplace-Name: Department of Soil Environment Sciences, Warsaw Agricultural University, Warsaw, Title: Causal pathways when independent variables are co-related: new interpretational possibilities Abstract: We propose a novel interpretation in classical path analysis, whereby the influence of k independent variables on a dependent variable can be analyzed. The approach should be useful to study a causal structure with the assumption that this structure is true for the situation investigated. We propose a new coefficient, Qi, which provides a better interpretation of classical path analysis. We provide an example in which effects of certain soil properties on grain yield of winter rye (Secale cereale L.) were examined. Keywords: causal systems, determination coefficient, indirect effects, path analysis Journal: Plant, Soil and Environment Pages: 267-275 Volume: 53 Issue: 6 Year: 2007 DOI: 10.17221/2220-PSE File-URL: http://pse.agriculturejournals.cz/doi/10.17221/2220-PSE.html File-Format: text/html X-File-Ref: http://agriculturejournals.cz/RePEc/caa/references/pse-200706-0005.txt Handle: RePEc:caa:jnlpse:v:53:y:2007:i:6:id:2220-PSE Template-Type: ReDIF-Article 1.0 Author-Name: J. Kořen Author-Workplace-Name: Hop Research Institute Co., Ltd., Žatec, Czech Republic Title: Influence of plantation row spacing on quality and yield of hops - Information Abstract: In 2004-2006 an influence of various plantation row spacings on yield and quality of hops was observed in field trials. A hybrid variety Agnus was selected for this purpose. The common space between the rows remained (300 cm). The tested distances of individual hop plants within each row amounted to 114 and 133 cm. We compared the standard kind of four trained bines from each hill with a new one (five bines per hill). The yield of hops was the highest if row spacing 300 × 114 cm was used (2.80 tons of dry hops per hectare). If spacing 300 × 133 cm was tested, the yield amounted to 2.69 t/ha. The lowest yield of hops was obtained when the common row spacing 300 × 100 cm was used (2.58 t/ha). Yield increase in the plots with new spacing was at the limit of significance. Weather was the main factor influencing hop crop in 2006. Statistically significant differences in the yield of hop cones were proved in the year with very good growing conditions (2005) as well as in the year with relatively bad weather conditions (2006). If average conditions prevailed (2004) no significant differences between experimental and control plots were observed. Alpha acid contents were the highest (12.45%) in the perspective row spacing (300 × 114 cm); a slight decrease was found when the spacing of 300 × 133 cm was used (11.92%). In the case of the control variant with the common row spacing 300 × 100 cm, alpha acid contents amounted to 12.29%. Keywords: hop, row spacing of plantation, yield and quality of hops, alpha acid contents Journal: Plant, Soil and Environment Pages: 276-282 Volume: 53 Issue: 6 Year: 2007 DOI: 10.17221/2219-PSE File-URL: http://pse.agriculturejournals.cz/doi/10.17221/2219-PSE.html File-Format: text/html X-File-Ref: http://agriculturejournals.cz/RePEc/caa/references/pse-200706-0006.txt Handle: RePEc:caa:jnlpse:v:53:y:2007:i:6:id:2219-PSE