Template-Type: ReDIF-Article 1.0 Author-Name: Jay S. Singh Author-Workplace-Name: Department of Environmental Science, Babasaheb Bhimrao Ambedkar (Central) University, Raibareli Road, Lucknow, India Author-Name: D.P. Singh Author-Workplace-Name: Department of Environmental Science, Babasaheb Bhimrao Ambedkar (Central) University, Raibareli Road, Lucknow, India Author-Name: A.K. Kashyap Author-Workplace-Name: Department of Botany, Banaras Hindu University, Varanasi, India Title: A comparative account of the microbial biomass-N and N-mineralization of soils under natural forest, grassland and crop field from dry tropical region, India Abstract: This study investigated microbial biomass-N (MB-N) and N-mineralization in soils of four different vegetation systems including forest (sal), mixed forest, savanna and cropland ecosystems in the Vindhyan region, India. A change was noted in the above region due to physiographic differences and anthropogenic disturbances. Annually the soil moisture (SM) content across the different study sites ranged from 7.5 to 24.3% being maximum in forest sites compared to savanna and cropland sites. The NH4+-N, NO -3 -N and MB-N concentrations varied from 4.3 to 10.2 μg/g, 1.1 to 5.8 μg/g and 21.3 to 90.2 μg/g dry soil, respectively, with minimum values in the wet and maximum values in the dry season. The trend of seasonal variation in net N-mineralization was similar to that of moisture content but counter to the concentrations of inorganic-N and MB-N. The net N-mineralization rates at different investigated sites ranged from 4.5 to 37.6 μg/g month. Cultivation reduced the N-mineralization and MB-N by 58.5% and 63.5%, respectively. Experiments showed that the percentage contribution of MB-N to total-N was 8.01 to 19.15%. MB-N was positively correlated with the inorganic-N (n = 180,r.80,P < 0.001) but negatively with soil moisture (n = 180, r = 0.79, P < 0.001) and net N-mineralization rates (n = 180, r = 0.92, P < 0.0001). The higher N-mineralization and MB-N in the soil of forest ecosystem was reported compared to savanna and cropland and the order of soil MB-N levels and net N-mineralization followed the sequence: forest (sal) > mixed forest > savanna > cropland. Keywords: dry tropical forest, cropland, microbial biomass, N-mineralization, soil moisture Journal: Plant, Soil and Environment Pages: 223-230 Volume: 55 Issue: 6 Year: 2009 DOI: 10.17221/1021-PSE File-URL: http://pse.agriculturejournals.cz/doi/10.17221/1021-PSE.html File-Format: text/html X-File-Ref: http://agriculturejournals.cz/RePEc/caa/references/pse-200906-0001.txt Handle: RePEc:caa:jnlpse:v:55:y:2009:i:6:id:1021-PSE Template-Type: ReDIF-Article 1.0 Author-Name: L. Růžek Author-Workplace-Name: Faculty of Agrobiology, Food and Natural Resources, Czech University of Life Sciences, Prague, Czech Republic Author-Name: M. Růžková Author-Workplace-Name: Faculty of Agrobiology, Food and Natural Resources, Czech University of Life Sciences, Prague, Czech Republic Author-Workplace-Name: Central Institute for Supervising and Testing in Agriculture, Brno, Czech Republic Author-Name: K. Voříšek Author-Workplace-Name: Faculty of Agrobiology, Food and Natural Resources, Czech University of Life Sciences, Prague, Czech Republic Author-Name: J. Kubát Author-Workplace-Name: Crop Research Institute, Prague, Czech Republic Author-Name: M. Friedlová Author-Workplace-Name: Crop Research Institute, Prague, Czech Republic Author-Name: O. Mikanová Author-Workplace-Name: Crop Research Institute, Prague, Czech Republic Title: Chemical and microbiological characterization of Cambisols, Luvisols and Stagnosols Abstract: Cambisols, Luvisols and Stagnosols are main soil taxonomical units covering 78% of the total area of the Czech Republic. In the period 2001-2008 soil samples from 13 arable and 2 grassed localities were collected and tested. Microbial biomass carbon (MBC) was determined using microwave irradiation method (MW), chloroform fumigation extraction method (FE) and re-hydration technique (RHD). Soil samples were moistened, according to the content of organic carbon (Corg), by deionized water addition (%Corg × 0.19 ml/g DM - dry mass of soil) immediately before MBC determination. Microwave sterilization (800 J/g DM = 600 W, 2 × 67 s, 100 g DM (10 soil samples) and microwave soil extracts digestion (800 J/ml = 250 W, 77 s, 24 ml) give the lowest values of MBC (204 ± 67 mg/kg DM; 100%) in comparison with FE (236 ± 57 mg/kg DM; 116%) and RHD (478 ± 138 mg/kg DM; 235%), respectively. High significant correlation (r = 0.9713) was found between TC (total carbon; 1.36 ± 0.29%) and TN (total nitrogen; 0.15 ± 0.03%) determined by CNS analyzer. Furthermore, high significant correlations were found between MBC-MW and MBC-RHD (r = 0.8965) as well as MBC-FE and DHA (dehydrogenase activity; r = 0.8094), respectively. DHA in studied soils reached 147 ± 68 mg of triphenylformazan/kg DM/24 h. Corg formed 96% of TC and total Kjeldahl nitrogen 97% of TN, respectively. According our results MW is fully acceptable for MBC determination. Keywords: microbial biomass, total carbon and nitrogen, K2SO4 extractable carbon, dehydrogenase, Cambisols, Luvisols, Inceptisols, Alfisols Journal: Plant, Soil and Environment Pages: 231-237 Volume: 55 Issue: 6 Year: 2009 DOI: 10.17221/35/2009-PSE File-URL: http://pse.agriculturejournals.cz/doi/10.17221/35/2009-PSE.html File-Format: text/html X-File-Ref: http://agriculturejournals.cz/RePEc/caa/references/pse-200906-0002.txt Handle: RePEc:caa:jnlpse:v:55:y:2009:i:6:id:35-2009-PSE Template-Type: ReDIF-Article 1.0 Author-Name: C.F. Oliveira Neto Author-Workplace-Name: Laboratório de Fisiologia Vegetal Avançada, Universidade Federal Rural da Amazônia, Belém, Brazil Author-Name: A.K.S. Lobato Author-Workplace-Name: Núcleo de Pesquisa Aplicada a Agricultura, Universidade Estadual de Maringá, Author-Name: R.C.L. Costa Author-Workplace-Name: Laboratório de Fisiologia Vegetal Avançada, Universidade Federal Rural da Amazônia, Belém, Brazil Author-Name: W.J.M.S. Maia Author-Workplace-Name: Laboratório de Fisiologia Vegetal Avançada, Universidade Federal Rural da Amazônia, Belém, Brazil Author-Name: B.G. Santos Filho Author-Workplace-Name: Laboratório de Fisiologia Vegetal Avançada, Universidade Federal Rural da Amazônia, Belém, Brazil Author-Name: G.A.R. Alves Author-Workplace-Name: Laboratório de Fisiologia Vegetal Avançada, Universidade Federal Rural da Amazônia, Belém, Brazil Author-Name: B. Brinez Author-Workplace-Name: Núcleo de Pesquisa Aplicada a Agricultura, Universidade Estadual de Maringá, Author-Name: H.K.B. Neves Author-Workplace-Name: Laboratório de Fisiologia Vegetal Avançada, Universidade Federal Rural da Amazônia, Belém, Brazil Author-Name: M.J. Santos Lopes Author-Workplace-Name: Laboratório de Fisiologia Vegetal Avançada, Universidade Federal Rural da Amazônia, Belém, Brazil Author-Name: F.J.R. Cruz Author-Workplace-Name: Laboratório de Fisiologia Vegetal Avançada, Universidade Federal Rural da Amazônia, Belém, Brazil Title: Nitrogen compounds and enzyme activities in sorghum induced to water deficit during three stages Abstract: The aim of this study was to evaluate and explicate the changes in the nitrogen compounds and enzyme activities in Sorghum bicolor plants (cv. BR-700) submitted to water deficit during vegetative, reproductive and maturation stages. The experimental design used was entirely randomized in factorial scheme, with two conditions (control and stress) combined with three stages (vegetative, reproductive and maturation). The nitrate level was increased at 180.6, 72.9 and 78.9% during the vegetative, reproductive and maturation stages, respectively. The total soluble amino acids and glycinebetaine increased only during vegetative and reproductive stages, if compared with control plants. However, besides protein levels during all stages, significant reductions were reported in nitrate reductase and glutamine synthetase activities; free ammonium presented decreases at 37.3 and 77.6% in vegetative and reproductive stages, respectively, when compared with control plants. Keywords: Sorghum bicolor L., nitrogen, nitrate, ammonium, water deficit Journal: Plant, Soil and Environment Pages: 238-244 Volume: 55 Issue: 6 Year: 2009 DOI: 10.17221/84/2009-PSE File-URL: http://pse.agriculturejournals.cz/doi/10.17221/84/2009-PSE.html File-Format: text/html X-File-Ref: http://agriculturejournals.cz/RePEc/caa/references/pse-200906-0003.txt Handle: RePEc:caa:jnlpse:v:55:y:2009:i:6:id:84-2009-PSE Template-Type: ReDIF-Article 1.0 Author-Name: L. Kolář Author-Workplace-Name: Agricultural Faculty, University of South Bohemia in České Budějovice, Czech Republic Author-Name: S. Kužel Author-Workplace-Name: Agricultural Faculty, University of South Bohemia in České Budějovice, Czech Republic Author-Name: J. Horáček Author-Workplace-Name: Agricultural Faculty, University of South Bohemia in České Budějovice, Czech Republic Author-Name: V. Čechová Author-Workplace-Name: Agricultural Faculty, University of South Bohemia in České Budějovice, Czech Republic Author-Name: J. Borová-Batt Author-Workplace-Name: Agricultural Faculty, University of South Bohemia in České Budějovice, Czech Republic Author-Name: J. Peterka Author-Workplace-Name: Agricultural Faculty, University of South Bohemia in České Budějovice, Czech Republic Title: Labile fractions of soil organic matter, their quantity and quality Abstract: The objective of the present paper is to contribute to the evaluation of quantity and quality of non-humified part of soil organic matter (SOM). In samples of soil organic matter from the humus profile of Šumava forest soils and forest meadows, taxonomically designated as mor and moder forms, the fractions of labile soil carbon Ccws, Chws, CPM and fraction of stable carbon represented by carbon of humus acids CHA and CFA were determined. Organic matter of samples was fractionated according to the degrees of hydrolyzability by two different methods in particle-size fractions of 2.00-0.25 mm and < 0.25 mm. The quality of labile fraction Chws was expressed on the basis of reaction kinetics as the rate constant of biochemical oxidation Kbio and rate constant of chemical oxidation Kchem of the first order reaction from a reduction in the concentration of C-compounds. The highest values of labile forms of carbon were determined in samples with the least favorable conditions for transformation processes of SOM, and these samples also had the highest content of labile forms in hydrolyses by both methods and the most labile fractions at the same time. The degree of SOM humification was strictly indirectly proportional to the lability of SOM and its hydrolyzability. The quality of labile fraction Chws can be expressed by both Kbio and Kchem while the sensitivity of Kbio is higher but the reproducibility of Kchem is better. Kbio corresponds with the degree of SOM transformation, Kchem with the proportion of CPM in total Cox. Keywords: primary soil organic matter, labile fraction, quality and quantity, degree of hydrolyzability, oxidation, reaction rate Journal: Plant, Soil and Environment Pages: 245-251 Volume: 55 Issue: 6 Year: 2009 DOI: 10.17221/87/2009-PSE File-URL: http://pse.agriculturejournals.cz/doi/10.17221/87/2009-PSE.html File-Format: text/html X-File-Ref: http://agriculturejournals.cz/RePEc/caa/references/pse-200906-0004.txt Handle: RePEc:caa:jnlpse:v:55:y:2009:i:6:id:87-2009-PSE Template-Type: ReDIF-Article 1.0 Author-Name: R. Asghari-Zakaria Author-Workplace-Name: Department of Crop Production and Breeding, Faculty of Agriculture, University of Mohaghegh Ardabili, Ardabil, Iran Author-Name: B. Maleki-Zanjani Author-Workplace-Name: Department of Crop Production and Breeding, Faculty of Agriculture, Zanjan University, Zanjan, Iran Author-Name: E. Sedghi Author-Workplace-Name: Department of Crop Production and Breeding, Faculty of Agriculture, Zanjan University, Zanjan, Iran Title: Effect of in vitro chitosan application on growth and minituber yield of Solanum tuberosum L. Abstract: In order to investigate the effects of soluble chitosan on plantlets growth in vitro and increase of minituber yield in potato micropropagation, plantlets of Agria cultivar were treated in vitrowith soluble chitosan at different concentrations including 0, 5, 15, 50, 150, 500, 750 and 1000 mg/l added to the MS tissue culture medium. Plantlets were subsequently transferred to the greenhouse and minituber yield parameters were evaluated. At the concentrations of 750 and 1000 mg/l of chitosan the culture medium failed to solidify. Application of 500 mg/l of soluble chitosan increased the shoot fresh weight, but its lower concentrations did not significantly affect this trait (P < 0.05). The 5 and 15 mg/l of soluble chitosan led to a significant increase in root fresh and dry weight of in vitro plantlets, whereas, higher concentrations, especially 500 mg/l, significantly decreased root fresh weight of in vitro plantlets. Application of 500 mg/l chitosan in vitro resulted in improved acclimatization of plantlets in the greenhouse as expressed by significant (P < 0.05) increase in minituber number and yield, compared to the control. The tested lower concentrations had no effect on yield parameters. The present results indicate that soluble chitosan can be successfully incorporated into potato seed production from in vitro plantlets. Keywords: chitosan, in vitro culture, micropropagation, minituber, potatoes Journal: Plant, Soil and Environment Pages: 252-256 Volume: 55 Issue: 6 Year: 2009 DOI: 10.17221/1018-PSE File-URL: http://pse.agriculturejournals.cz/doi/10.17221/1018-PSE.html File-Format: text/html X-File-Ref: http://agriculturejournals.cz/RePEc/caa/references/pse-200906-0005.txt Handle: RePEc:caa:jnlpse:v:55:y:2009:i:6:id:1018-PSE Template-Type: ReDIF-Article 1.0 Author-Name: M. Trnka Author-Workplace-Name: Institute of Agrosystems and Bioclimatology, Mendel University of Agriculture and Forestry Brno, Czech Republic Author-Name: J. Eitzinger Author-Workplace-Name: Institute of Meteorology, University of Natural Resources and Applied Life Sciences, Vienna, Austria Author-Name: P. Hlavinka Author-Workplace-Name: Institute of Agrosystems and Bioclimatology, Mendel University of Agriculture and Forestry Brno, Czech Republic Author-Name: M. Dubrovský Author-Workplace-Name: Institute of Agrosystems and Bioclimatology, Mendel University of Agriculture and Forestry Brno, Czech Republic Author-Name: D. Semerádová Author-Workplace-Name: Institute of Agrosystems and Bioclimatology, Mendel University of Agriculture and Forestry Brno, Czech Republic Author-Name: P. Štěpánek Author-Workplace-Name: Czech Hydrometeorological Institute, Department of Meteorology and Climatology, Brno, Czech Republic Author-Name: S. Thaler Author-Workplace-Name: Institute of Meteorology, University of Natural Resources and Applied Life Sciences, Vienna, Austria Author-Name: Z. Žalud Author-Workplace-Name: Institute of Agrosystems and Bioclimatology, Mendel University of Agriculture and Forestry Brno, Czech Republic Author-Name: M. Možný Author-Workplace-Name: Czech Hydrometeorological Institute, Department of Meteorology and Climatology, Brno, Czech Republic Author-Name: H. Formayer Author-Workplace-Name: Institute of Meteorology, University of Natural Resources and Applied Life Sciences, Vienna, Austria Title: Climate-driven changes of production regions in Central Europe Abstract: The presented work complements studies on agroclimatic zoning that were performed during 19th and 20th century in the Czech Republic and Austria and allows estimating the effect of climate change on the spatial distribution of agroclimatic conditions within both countries. The main conclusions of the study are: (1) The combination of increased air temperature and changes in the amount and distribution of precipitation will lead to significant shifts in the agroclimatic zones by the 2020's. The current most productive areas will be reduced and replaced by warmer but drier conditions, which are considered less suitable for rainfed farming. (2) While trends in the changes expected in lowlands are mostly negative (especially for non-irrigated crops), higher elevations might experience improvement in their agroclimatic production potential. However, the production potential of these regions is usually limited by other factors such as the soil quality and terrain accessibility. Additionally, these positive effects might be shortlived, as by the 2050's, even the areas in higher altitudes might experience much drier conditions than nowadays. (3) Dairy-oriented agriculture (based on permanent grassland production) at higher altitudes could suffer through an increased evapotranspiration demand combined with a decrease in precipitation, leading to higher water deficits and yield variations. (4) All above listed changes will most likely occur within less than four decades. The rate of change might be so high that the concept of agroclimatic zoning itself might lose its relevance due to the perpetual change. Keywords: climate change, agroclimatic zoning, water deficit, growing season, AgriClim Journal: Plant, Soil and Environment Pages: 257-266 Volume: 55 Issue: 6 Year: 2009 DOI: 10.17221/1017-PSE File-URL: http://pse.agriculturejournals.cz/doi/10.17221/1017-PSE.html File-Format: text/html X-File-Ref: http://agriculturejournals.cz/RePEc/caa/references/pse-200906-0006.txt Handle: RePEc:caa:jnlpse:v:55:y:2009:i:6:id:1017-PSE