Template-Type: ReDIF-Article 1.0 Author-Name: M. Hejcman Author-Workplace-Name: Department of Ecology, Faculty of Environmental Sciences, Czech University of Life Sciences Prague, Prague, Czech Republic Author-Workplace-Name: Crop Research Institute, Prague, Czech Republic Author-Name: J. Schellberg Author-Workplace-Name: Institute of Crop Science and Resource Conservation, University of Bonn, Author-Name: V. Pavlů Author-Workplace-Name: Department of Ecology, Faculty of Environmental Sciences, Czech University of Life Sciences Prague, Prague, Czech Republic Author-Workplace-Name: Crop Research Institute, Prague, Czech Republic Title: Competitive ability of Rhinanthus minor L. in relation to productivityin the Rengen Grassland Experiment Abstract: Rhinanthus minor (yellow-rattle) can be used for restoration of species-rich grasslands but is vulnerable to competitive exclusion from high total aboveground biomass production of vascular plants. We asked (1) whether there is a threshold limit for total annual aboveground biomass production of vascular plants above which R. minor cannot establish viable population in grasslands and (2) how is cover of R. minor in grassland related to standing biomass of bryophytes. Data were collected in the Rengen Grassland Experiment (RGE) established in Germany in 1941 with following fertilizer treatments: unfertilized control, application of Ca, CaN, CaNP, CaNPKCl and CaNPK2SO4. Cover of R. minor and total annual aboveground biomass production of vascular plants were determined from 2005 to 2009. Further relationship between standing biomass of bryophytes and cover of R. minor was analyzed in 2006. Mean cover of R. minor over five years ranged from 0.7% to 12.3% in CaNPK2SO4 and control treatments, respectively. Cover of R. minor was significantly negatively related to total annual aboveground biomass production of vascular plants and cover of R. minor was below 3% in all plots with total annual aboveground dry matter biomass production of vascular plants higher than 5 t/ha. Although cover of R. minor was markedly reduced in highly productive plots in the RGE, high standing biomass of bryophytes (1.8 t/ha) in low productive control was not an obstacle for establishment of its viable population. We concluded, that viable population of R. minor can be established in grasslands only if total annual aboveground dry matter biomass production of vascular plants is below 5 t/ha regardless on standing biomass of bryophytes. Keywords: biomass production, long-term fertilizer application, plant nutrition, yellow-rattle, semi-natural grassland restoration Journal: Plant, Soil and Environment Pages: 45-51 Volume: 57 Issue: 2 Year: 2011 DOI: 10.17221/197/2010-PSE File-URL: http://pse.agriculturejournals.cz/doi/10.17221/197/2010-PSE.html File-Format: text/html X-File-Ref: http://agriculturejournals.cz/RePEc/caa/references/pse-201102-0001.txt Handle: RePEc:caa:jnlpse:v:57:y:2011:i:2:id:197-2010-PSE Template-Type: ReDIF-Article 1.0 Author-Name: E. Jafariehyazdi Author-Workplace-Name: Biology Department, Parand Branch Islamic Azad University, Parand, Iran Author-Name: F. Javidfar Author-Workplace-Name: Oilseed Department, Seed and Plant Improvement Institute, Karaj, Iran Title: Comparison of allelopathic effects of some brassica species in two growth stages on germination and growth of sunflower Abstract: Members of Brassicaceae have been frequently cited as allelopathic crop. The toxic effect of Brassica spp. may be caused by hydrolysis products of glucosinolates that occur in substantial amounts in the vegetative parts of Brassica spp. This study investigated the allelopathic potential of Brassica napus, B. rapa and B. juncea on the sunflower seed germination and seedling growth. Aqueous extracts of three species from two stages (full flowering and straw) of sampling were separately made with 0 (distilled water), 10, 20, 30 and 40% concentrations. This experiment was conducted in 2 × 3 × 5 factorial arrangement based on completely randomized design with five replications. There was a highly significant difference among different concentrations of extracts and also between two stages of extraction. All aqueous extracts significantly affected sunflower germination, germination rate, seedling root and hypocotyl length, fresh and dry matter weight when compared with distilled water control. The greatest concentration showed a stronger inhibitory effect. Root length was more sensitive to extracts than hypocotyl length. Keywords: allelopathy, Brassica, Helianthus annuus, seedling growth Journal: Plant, Soil and Environment Pages: 52-56 Volume: 57 Issue: 2 Year: 2011 DOI: 10.17221/139/2010-PSE File-URL: http://pse.agriculturejournals.cz/doi/10.17221/139/2010-PSE.html File-Format: text/html X-File-Ref: http://agriculturejournals.cz/RePEc/caa/references/pse-201102-0002.txt Handle: RePEc:caa:jnlpse:v:57:y:2011:i:2:id:139-2010-PSE Template-Type: ReDIF-Article 1.0 Author-Name: N. Vrchotová Author-Workplace-Name: Instituteof Systems Biology and Ecology of the Academy of Sciences of the Czech Republic, České Budějovice, Czech Republic Author-Name: B. Šerá Author-Workplace-Name: Instituteof Systems Biology and Ecology of the Academy of Sciences of the Czech Republic, České Budějovice, Czech Republic Author-Name: J. Krejčová Author-Workplace-Name: University of South Bohemia, Faculty of Agriculture, České Budějovice, Czech Republic Title: Allelopathic activity of extracts from Impatiens species Abstract: We have tested the effect of water, methanol and dichloromethane extracts from the leaves of several species of Impatiens (I. noli-tangere, I. parviflora, I. glandulifera) on germination of seeds Leucosinapis alba and Brassica napus. All of the tested extracts had inhibitory effects to seeds of all studied plants (except the dichloromethane extracts). The highest activity revealed methanol extract and extract from I. glandulifera. Keywords: Impatiens, allelopathy, inhibitory effect Journal: Plant, Soil and Environment Pages: 57-60 Volume: 57 Issue: 2 Year: 2011 DOI: 10.17221/156/2010-PSE File-URL: http://pse.agriculturejournals.cz/doi/10.17221/156/2010-PSE.html File-Format: text/html X-File-Ref: http://agriculturejournals.cz/RePEc/caa/references/pse-201102-0003.txt Handle: RePEc:caa:jnlpse:v:57:y:2011:i:2:id:156-2010-PSE Template-Type: ReDIF-Article 1.0 Author-Name: M. Shujie Author-Workplace-Name: Northeast Institute of Geography and Agro-Ecology, Chinese Academy of Sciences, Harbin, P.R. China Author-Name: Q. Yunfa Author-Workplace-Name: Northeast Institute of Geography and Agro-Ecology, Chinese Academy of Sciences, Harbin, P.R. China Title: Effects of phosphorus concentration on adaptive mechanisms of high- and low-P efficiency soybean genotypes when grown in solution Abstract: Low availability of phosphorus (P) in soil is a major constraint for crop production in agricultural ecosystems. Therefore, it is very important to explain the adaptive mechanism of crops under low P conditions. The response of high- and low-P efficient soybean (Glycine max L.) genotypes to various external P level was carried out in nutrient solution culture. Results showed that Dongnong1031 (low P-efficient genotype) undergoes major changes in terms of dry mass, root length, root number and root surface, while these response of Hai 616 (high P-efficient genotype) was lower after five weeks of growth. The higher P level in solution, the smaller difference between the two genotypes in these parameters. The amount of H+ released by root of Dongnong1031 was lower than that of Hai 616, except when supplied with 50 μmol external P. There was a positive relationship between RPAE (relative phosphorus absorption efficiency) and P concentration in shoot and root material at all P levels, irrespective of soybean genotype. An exponential relationship was found between PUE (phosphorus utilization efficiency) and P concentrations in shoots and roots. These results suggested that an increase in measured root parameters coupled with H+ release by roots were key mechanisms for soybean genotypes with high-P efficiency to cope with low P conditions when grown in solution. In order to best select high soybean genotype with high-P efficiency one should pay attention to PUE combined with high RPAE. Keywords: soybean, phosphorus, P efficiency, adaptive mechanism Journal: Plant, Soil and Environment Pages: 61-66 Volume: 57 Issue: 2 Year: 2011 DOI: 10.17221/143/2010-PSE File-URL: http://pse.agriculturejournals.cz/doi/10.17221/143/2010-PSE.html File-Format: text/html X-File-Ref: http://agriculturejournals.cz/RePEc/caa/references/pse-201102-0004.txt Handle: RePEc:caa:jnlpse:v:57:y:2011:i:2:id:143-2010-PSE Template-Type: ReDIF-Article 1.0 Author-Name: Z.H. Chen Author-Workplace-Name: Institute of Applied Ecology, Chinese Academy of Sciences, Shenyang, P.R. China Author-Name: L.J. Chen Author-Workplace-Name: Institute of Applied Ecology, Chinese Academy of Sciences, Shenyang, P.R. China Author-Name: Y.L. Zhang Author-Workplace-Name: Institute of Applied Ecology, Chinese Academy of Sciences, Shenyang, P.R. China Author-Name: Z.J. Wu Author-Workplace-Name: Institute of Applied Ecology, Chinese Academy of Sciences, Shenyang, P.R. China Title: Microbial properties, enzyme activities and the persistence of exogenous proteins in soil under consecutive cultivation of transgenic cottons (Gossypium hirsutum L.) Abstract: One Bacillus thuringiensis (Bt) and two stacked Bt and cowpea trypsin inhibitor (Bt + CpTI) cottons and their non-transgenic isolines were consecutively cultivated to investigate the soil persistence of Cry1Ac and CpTI proteins and their effects on microbial properties and enzyme activities involving C, N, P, and S cycling in soil. Results showed that there were the persistence of Cry1Ac and CpTI proteins in soil under 4-year consecutive cultivation of transgenic cottons. Cry1Ac proteins varied from 6.75 ng/g to 12.01 ng/g and CpTI proteins varied from 30.65 to 43.60 ng/g. However, neither of these two proteins was detected in soil under non-transgenic cottons. Soil microbial biomass carbon, microbial activities, and soil enzyme activities (except urease and phosphodiesterase) significantly decreased in soil under transgenic cottons. Correlation analysis showed that most of microbial properties and enzyme activities in soil had a negative relationship with Cry1Ac content, while most of them had a positive relationship with CpTI content. Our data indicate that consecutive cultivation by genetically modified cottons with Bt and CpTI genes can result in persistence of Cry1Ac and CpTI proteins and negatively affect soil microbial and biochemical properties. Keywords: genetically modified plants, pest-resistant cotton, soil biological properties, insecticidal toxin, anti-nutritional factor Journal: Plant, Soil and Environment Pages: 67-74 Volume: 57 Issue: 2 Year: 2011 DOI: 10.17221/237/2010-PSE File-URL: http://pse.agriculturejournals.cz/doi/10.17221/237/2010-PSE.html File-Format: text/html X-File-Ref: http://agriculturejournals.cz/RePEc/caa/references/pse-201102-0005.txt Handle: RePEc:caa:jnlpse:v:57:y:2011:i:2:id:237-2010-PSE Template-Type: ReDIF-Article 1.0 Author-Name: V.M. Ngole Author-Workplace-Name: Faculty of Science, Engineering, and Technology, Walter Sisulu University, Mthatha, South Africa Title: Using soil heavy metal enrichment and mobility factors to determine potential uptake by vegetables Abstract: This study investigated copper (Cu) and lead (Pb) enrichment factor (EF) and mobility factor (MF) as possible indicators of their uptake by spinach (Spinaceae oleraceae) and carrots (Daucus carota) grown on a sludge-amended luvisol (SAL). Sewage sludge was applied to luvisol at different rates and spinach and carrots planted. Enrichment of Cu and Pb in SAL was determined, and values regressed with those of Cu and Pb concentrations in spinach and carrots. Concentration of Cu and Pb in vegetables was calculated using the regression model obtained, and calculated values compared with actual values. Pb MF were higher than Cu MF but Cu and Pb EFsoil values were < 3.0, indicating minor enrichment from sludge addition. EF had 10% reliability in predicting Cu and Pb uptake in vegetables. MF was more than 70% reliable in predicting carrot Cu uptake and spinach Pb uptake. EF and MF are not effective as predictors of heavy metal uptake by vegetables. The role of other soil components including root exudates and by-products from microbial activities should also be investigated. Keywords: bioavailability, luvisol, sludge application, regression model Journal: Plant, Soil and Environment Pages: 75-80 Volume: 57 Issue: 2 Year: 2011 DOI: 10.17221/125/2010-PSE File-URL: http://pse.agriculturejournals.cz/doi/10.17221/125/2010-PSE.html File-Format: text/html X-File-Ref: http://agriculturejournals.cz/RePEc/caa/references/pse-201102-0006.txt Handle: RePEc:caa:jnlpse:v:57:y:2011:i:2:id:125-2010-PSE Template-Type: ReDIF-Article 1.0 Author-Name: J. Hakl Author-Workplace-Name: Department of Forage Crops and Grassland Management, Faculty of Agrobiology, Food and Natural Resources, Czech University of Life Sciences Prague, Prague, Czech Republic Author-Name: P. Fuksa Author-Workplace-Name: Department of Forage Crops and Grassland Management, Faculty of Agrobiology, Food and Natural Resources, Czech University of Life Sciences Prague, Prague, Czech Republic Author-Name: J. Šantrůček Author-Workplace-Name: Department of Forage Crops and Grassland Management, Faculty of Agrobiology, Food and Natural Resources, Czech University of Life Sciences Prague, Prague, Czech Republic Author-Name: K. Mášková Author-Workplace-Name: Department of Forage Crops and Grassland Management, Faculty of Agrobiology, Food and Natural Resources, Czech University of Life Sciences Prague, Prague, Czech Republic Title: The development of lucerne root morphology traits under high initial stand density within a seven year period Abstract: The root system of plants is generally regarded as a factor, which is in relation to important agronomic and ecological characteristics. The aim of this study was to investigate the effect of high initial stand density on the reduction in development of lucerne root morphology traits and how long-term this effect would be. In spring 2003, a field experiment with six lucerne entries in randomized blocks was established. Broadcast sowing was used and the seeding rate was 5000 germinated seeds per m2. In 2003-2009, the plants were sampled in each plot in autumn; the average depth of sampling was 0.2 m. The stand density reached an average value of 860 plants per m2 in the autumn of the seeding year and this strongly reduced the root weight, tap-root diameter, position and number of lateral roots. The subsequent decrease of stand density to 57 plants/m2 in 2009 was not linear but it was extremely quick from the 1st to 2nd year and, by contrast, it was extremely slow in the last three years. It indicates that older plants with larger tap-root diameter probably have a higher persistency. All evaluated root traits were developed slowly, nevertheless, they reached common values during a seven year period. The intensity of the relation of stand density to root weight or tap-root diameter increased over time whilst it decreased to the ratio of root-branched plants. Results suggest that an assessment of density in samples should be recommended for the varieties evaluation in case of irregularly-spaced plants because the differences in root morphology among varieties could be caused by the differences in density among the varieties. It is possible to conclude that lucerne stands under higher initial density provided a strongly reduced speed of root development with an impact on important agronomic traits connected with root morphology. Keywords: alfalfa, Medicago, long-term experiment, tap-root, lateral root Journal: Plant, Soil and Environment Pages: 81-87 Volume: 57 Issue: 2 Year: 2011 DOI: 10.17221/186/2010-PSE File-URL: http://pse.agriculturejournals.cz/doi/10.17221/186/2010-PSE.html File-Format: text/html X-File-Ref: http://agriculturejournals.cz/RePEc/caa/references/pse-201102-0007.txt Handle: RePEc:caa:jnlpse:v:57:y:2011:i:2:id:186-2010-PSE Template-Type: ReDIF-Article 1.0 Author-Name: M. Růžková Author-Workplace-Name: Central Institute for Supervising and Testing in Agriculture, Brno, Czech Republic Author-Name: L. Růžek Author-Workplace-Name: Faculty of Agrobiology, Food and Natural Resources, Czech University of Life Sciences Prague, Prague, Czech Republic Author-Name: K. Voříšek Author-Workplace-Name: Faculty of Agrobiology, Food and Natural Resources, Czech University of Life Sciences Prague, Prague, Czech Republic Author-Name: P. Vráblík Author-Workplace-Name: Faculty of Environment, University of Jan Evangelista Purkyne, Ústí nad Labem, Czech Republic Author-Name: D. Musilová Author-Workplace-Name: Faculty of Science and Engineering, York University, Toronto, Ontario, Canada Title: Microbiological characterization of land set-aside before and after Roundup desiccation Abstract: Luvic chernozem (set-aside from 1996) was evaluated. The first period, before Roundup desiccation (2002-2003), was characterized by black, spontaneous and controlled fallows (mowed with the removal of plant biomass or mulched); the following period (2003-2004) by black fallow with repeated Roundup applications; and the last period (2004-2006) involved re-grassing by a mowed Lolium multiflorum Lam. monoculture. The characterization included microbial biomass, available organic carbon, basal respiration, metabolic quotient, biomass-specific available organic carbon, arylsulfatase activity, soil organic matter carbon and total nitrogen. Mulching of pure cultures of grasses and legumes contributed to a high soil organic matter accumulation. Repeated Roundup desiccation caused a strong (highly significant) decrease of arylsulfatase activity (-28%), however highly significant increase of microbial biomass (+69%) and nitrate-nitrogen (+86%) were determined. The subsequent re-grassing compensated the changes described. The soil biological properties were best preserved on mulched fallow with Lotus corniculatus L. and Festuca pratensis L., also in regard to contamination with weeds. Keywords: fallow, microbial biomass, metabolic quotient, respiration, arylsulfatase Journal: Plant, Soil and Environment Pages: 88-94 Volume: 57 Issue: 2 Year: 2011 DOI: 10.17221/226/2010-PSE File-URL: http://pse.agriculturejournals.cz/doi/10.17221/226/2010-PSE.html File-Format: text/html X-File-Ref: http://agriculturejournals.cz/RePEc/caa/references/pse-201102-0008.txt Handle: RePEc:caa:jnlpse:v:57:y:2011:i:2:id:226-2010-PSE