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Results 391 to 420 of 644:

The effect of light availability on leaf area index, biomass production and plant species composition of park grasslands in WarsawOriginal Paper

P. Dąbrowski, B. Pawluśkiewicz, H.M. Kalaji, A.H. Baczewska

Plant Soil Environ., 2013, 59(12):543-548 | DOI: 10.17221/140/2013-PSE

How light conditions affect development of park grasslands is a question that has not been satisfactory addressed. The aim of this study was therefore determination of the level to which unfavorable light conditions influence grassy parks area and relationships between parameters which determine state of turf grasses. Researches were conducted in two parks in Warsaw, in various light conditions and included measurement of: leaf density, sward height, leaf area index (LAI), and botanical composition of the communities. The leaf density of shaded areas did not exceed 70%. LAI value varied from 0.5 to 0.9-fold lower than in the areas in half-shade and in sun. The participation of basic lawn species at Skaryszewski Park was higher under shade, while at Łazienki Królewskie was higher in full-sunlight areas. The state of tested grassy areas in limited solar radiation does not satisfy the requirements of recreational and representational functions. The development processes of vegetation coverage were inhibited at the sites of lower solar radiation. LAI was influenced by both leaf coverage and sward height. Agrostis stolonifera and Poa trivialis may be recommended to create grass areas under limited solar radiation.

The Fluvisol and sediment trace element contamination level as related to their geogenic and anthropogenic sourceOriginal Paper

R. Vácha, M. Sáňka, O. Sáňka, J. Skála, J. Čechmánková

Plant Soil Environ., 2013, 59(3):136-142 | DOI: 10.17221/723/2012-PSE

The upper values of the extractability of trace elements (As, Be, Cd, Co, Cr, Cu, Ni, Pb and Zn) in 2 mol/L HNO3 and 0.025 mol/L ethylenediaminetetraacetic acid (EDTA) (compared with their pseudototal content in aqua regia) for determination of prevailing anthropogenic and geogenic soil load were proposed and compared with the results of the other 30 Fluvisol samples collected from the Labe fluvial zone. The increased geogenic load of Fluvisols was confirmed in the case of Be and As in some localities where low extractability with increased pseudototal contents were detected as opposed to the other elements when their increased pseudototal contents were followed by their increased extractability. The maps of probability of increased geogenic soil load in the area of the Czech Republic based on the comparison of geological substrates and trace element load were constructed. The combination of proposed elements extractability values for geogenic load together with developed maps is a suitable tool for the definition of prevailing Fluvisol or sediment load on some localities in the whole area of the Czech Republic. The results can be also a useful tool in the decision making processes regarding dredged sediment application on agricultural soil (support tool for legislative norms, Direction No. 257/2009 Sb.).

Effects of cattle slurry application on plant species composition of moderately moist Arrhenatherion grasslandOriginal Paper

R. Duffková, H. Libichová

Plant Soil Environ., 2013, 59(11):485-491 | DOI: 10.17221/62/2013-PSE

Cattle slurry is frequently used fertilizer on grasslands, but little is known about its effect on plant species composition. The aim of this study was therefore to assess effect of different application rates of cattle slurry (S0 - 0, S1 - 60, S2 - 120, S3 - 180, S4 - 240 kg N/ha/year) on the plant species composition of three-cut grassland. The study was performed over 6 years on moderately moist upland Arrhenatherion grassland in the Czech Republic dominated by Alopecurus pratensis, Trisetum flavescens, and Poa spp. Species composition recorded in treatments with application of cattle slurry in rate up to 120 kg N/ha/year was similar to the unfertilized control. During first three years, species richness was similar in all treatments and then decreased the most in S4 followed by S3 treatment. Cover of short forbs increased in S0 and decreased with an increase in slurry application rate which supported tall grasses. Application of cattle slurry up to 120 kg N/ha/year can be considered as suitable compromise between maintenance of species rich grasslands and requirements of farmers for sufficient forage production.

Long-term effects of returning wheat straw to croplands on soil compaction and nutrient availability under conventional tillage

Z. Guo, D.Z. Wang

Plant Soil Environ., 2013, 59(6):280-286 | DOI: 10.17221/846/2012-PSE

To investigate the effects of returning wheat straw to croplands on soil compaction and nutrient availability, this trial was designed: (1) planted crops without fertilization (NF); (2) natural land without human activities (CT); (3) applied mineral fertilizers in combination with 7500 kg/ha wheat straw (WS-NPK); (4) applied mineral fertilizers in combination with 3750 kg/ha wheat straw (1/2WS-NPK); and (5) applied mineral fertilizers alone (NPK). It is found that, compared with NPK, the soil bulk density in 1/2WS-NPK and WS-NPK both decreased by more than 10% in the 0 cm to 15 cm layer, and by 6.93% and 9.14% in the 15 cm to 20 cm, respectively. Furthermore, in contrast to NPK, the soil available nitrogen in the 0 cm to 25 cm layer in 1/2WS-NPK and WS-NPK were higher by 17.43% and 35.19%, and the soil available potassium were higher by 7.66% and 17.47%, respectively. For soil available phosphorus in the depth of 5 cm to 25 cm, it was higher by 18.51% in 1/2WS-NPK and by 56.97% in WS-NPK, respectively. Therefore, returning wheat straw to croplands effectively improves soil compaction and nutrients availability, and the improvement in soil nitrogen and phosphorus availability is closely related to the amount of wheat straw.

Effects of Beauveria bassiana and acephate on enzyme activities and microbial diversity in paddy soilOriginal Paper

W. Du, J. Zhou, P. Jiang, T. Yang, Y.Q. Bu, C.H. Liu, C.C. Dai

Plant Soil Environ., 2013, 59(12):562-567 | DOI: 10.17221/447/2013-PSE

To investigate the ecological safety of Beauveria bassiana in soil, we evaluated the effects of different concentrations of B. bassiana spores suspensions and acephate on paddy soil microbial flora and enzyme activities in a potted trial. Results showed that B. bassiana can increase the quantity of bacteria and fungi on day 10 and 30, while it showed inhibition on actinomycetes growth on day 10. However, acephate reduced the quantity of bacteria, fungi, and actinomycetes in soil. Investigation of enzyme activities revealed that invertase activity declined during prophase, while urease activity decreased later in B. bassiana treatment groups, and there were no significant changes in alkaline phosphatase or dehydrogenase activity. Acephate showed higher inhibition rates of enzymes. B. bassiana treatment at lower concentrations showed a higher yield. Overall, compared with the acephate, B. bassiana is an effective, environmentally friendly microbial pesticide in this system.

Water use of winter cereals under well-watered and drought-stressed conditionsOriginal Paper

B. Varga, E. Varga-László, S. Bencze, K. Balla, O. Veisz

Plant Soil Environ., 2013, 59(4):150-155 | DOI: 10.17221/658/2012-PSE

A reduction in the water available to plants will lend increasing importance to the dynamics of water uptake and to the water use efficiency (WUE) of cereals. The effect of drought on the water use efficiency of winter cereals was investigated in a greenhouse experiment in the Centre for Agricultural Research. The effect of water deficiency on the water use properties was studied by measuring changes in the grain weight, thousand-kernel weight and aboveground biomass. The water use efficiency of wheat varieties generally ranged from 1.5-2.3 kg/m3 and 1.06-2.0 kg/m3 in the case of optimum and limited water supplies, respectively, while these figures were 1.4 kg/m3 and 0.8 kg/m3 for winter barley and 0.8 kg/m3 and 0.5 kg/m3 for winter oat. Investigation on the relationship between harvest index (HI) and WUE was found that the harvest index is only one indicator of drought tolerance; but the stability of HI under non-optimum environmental conditions also needs to be determined.

Accumulation of copper and zinc in soil and plant within ten-year application of different pig manure ratesOriginal Paper

Y. Xu, W. Yu, Q. Ma, H. Zhou

Plant Soil Environ., 2013, 59(11):492-499 | DOI: 10.17221/121/2013-PSE

Fertilization of crops with pig manure is a common practice throughout the world. Nevertheless, due to the relatively high copper (Cu) and zinc (Zn) contents in pig manure, continuous application of pig manure could have negative effects on soil and plant. The study aimed at the impacts of long-term applying different pig manure rates (equivalently 0, 100, 250 and 500 kg total N/ha/year from 2002 to 2008 and 0, 10, 25 and 50 t fresh weight/ha/year from 2009 to 2011, respectively) on Cu and Zn accumulation in soil and plant. During the 10 years of the experiment, a total of 2.04 to 10.20 kg/ha/year for Cu, 3.15 to 15.73 kg/ha/year for Zn were applied to the soil. Results from this study showed that long-term pig manure application resulted in serious accumulation of Cu and Zn in soil, total Cu and Zn concentrations increased by 204% and 107% at high application rates, respectively. Although topsoil Cu and Zn concentrations were below concentrations considered phytotoxic to crops, according to current Chinese legislation, it would take only less time than 16 and 27 years of high application rates to reach the allowable limits. Our result also suggested that Cu and Zn leaching occurred in the tested soil. The Cu and Zn concentrations in stalks and grains were not affected by the application of pig manure, and these values were lower than the threshold values for animal and human ingestion.

Consequences of the water deficit on water relations and symbiosis in Vigna unguiculata cultivars

A.K.S. Lobato, R.C.L. Costa, C.F. Oliveira Neto, B.G. Santos Filho, M.C. Gonçalves-Vidigal, P.S. Vidigal Filho, C.R. Silva, F.J.R. Cruz, P.M.P. Carvalho, P.C.M. Santos, A. Gonela

Plant Soil Environ., 2009, 55(4):139-145 | DOI: 10.17221/1615-PSE

The study aimed at evaluating and comparing changes provoked by the water deficit on water relations and nitrogen fixation in two Vigna unguiculata cultivars, as well as at indicating which cultivar is more tolerant under water deficiency. The experimental design used was entirely randomized in factorial scheme, with 2 cultivars (Pitiuba and Pérola) and 2 water regimes (control and stress). The parameters evaluated were the leaf relative water content, stomatal conductance, transpiration rate, nodule number, nodule dry matter, nitrate reductase enzyme activity, ureide concentration and leghemoglobin in nodule. The stomatal conductance of the Pitiuba and Pérola cultivars under water deficit were 0.20 and 0.01 mmol H2O/m2/s, respectively. The nitrate reductase activity of the plants under stress was significantly reduced in both cultivars. The leghemoglobin in the Pitiuba and Pérola cultivars under water stress had the concentrations of 58 and 41 g/kg dry matter, respectively. The parameters investigated in this study suggest that the Pitiuba cultivar under water deficit suffers from smaller changes, when compared with Pérola cultivar.

Effect of zinc foliar application on grain yield of maize and its yielding compone

J. Potarzycki, W. Grzebisz

Plant Soil Environ., 2009, 55(12):519-527 | DOI: 10.17221/95/2009-PSE

Actual yields of maize harvested by farmers are at level much below attainable yield potential of currently cultivated varieties. Among many growth factors zinc was recognized as one of main limiting factors of maize crop growth and yielding. This hypothesis has been verified within a three-year field study, where zinc fertilizer was applied to maize plants at the 5th leaf stage. Maize crop responded significantly to zinc foliar application in two of three years of study. The optimal rate of zinc foliar spray for achieving significant grain yield response was in the range from 1.0 to 1.5 kg Zn/ha. Grain yield increase was circa 18% (mean of three years) as compared to the treatment fertilized only with NPK. Plants fertilized with 1.0 kg Zn/ha significantly increased both total N uptake and grain yield. Yield forming effect of zinc fertilizer revealed via improvement of yield structure elements. The number of kernels per plant showed the highest response (+17.8% as compared to the NPK plot) and simultaneously the highest dependence on N uptake (R2 = 0.79). For this particular zinc treatment, however, the length of cob can also be applied as a component of yield structure significantly shaping the final grain yield.

Population density and soil seed bank of weed beet as influenced by crop sequence and soil tillage

M. Landová, K. Hamouzová, J. Soukup, M. Jursík, J. Holec, G.R. Squire

Plant Soil Environ., 2010, 56(11):541-549 | DOI: 10.17221/1457-PSE

Dynamics of population density and soil seed bank of weed beet was studied in a 5 year crop rotation consisting of spring barley, and sugar beet. Beside the crop rotation experiment, the seeds of weed beet were studied for their dormancy and viability in soil seed bank over the period of four years. The obtained data indicates that weed beet was able to produce seeds only in sugar beet, but not in barley. In sugar beet, its reproductive potential allows weed beet to restore and increase the soil seed bank of glomerules rapidly. Common infestation of sugar beet is able to persist over more than the 2-year period between repeated introductions of sugar beet in crop rotation. The experiment has also proven the negative effect of weed beet presence on sugar beet yield. The sugar beet root yield decreased of 0.4 t/ha with every 1000 weed beet plants per hectare. The yearly loss of viable seeds was about 75%. The number of surviving seeds decreased exponentially in time. Less than 2% of seeds remained viable after three years in the soil. Seasonal fluctuations of seed dormancy were observed. Seeds were dormant in autumn, lost dormancy in winter and recovered it in late summer.

Growth and physiological performance responses to drought stress under non-flooded rice cultivation with straw mulching

J. Qin, X. Wang, F. Hu, H. Li

Plant Soil Environ., 2010, 56(2):51-59 | DOI: 10.17221/157/2009-PSE

A field experiment was performed to investigate the growth performance and the growth stage-dependent changes in activities of antioxidative enzymes and concentration of malondialdehyde (MDA) in leaves of rice subjected to treatment with (NF-M) or without straw mulching (NF-WM) under non-flooded conditions compared with continuously flooded treatment (CF). Compared with the NF-WM treatment, mulch application significantly increased the flag leaf area per plant before heading, tillers number and plant height at the early period of tillering stage. There was no significant difference between the yield of the NF-WM and CF treatment. However, the yield of NF-WM treatment was significantly lower than CF and NF-M treatments. Significantly higher activities of peroxidase (POD) and catalase (CAT) but lower concentration of superoxide dismutase (SOD) and malondialdehyde (MDA) were observed in straw mulching treatment than in treatment without mulching at elongation, heading and grain filling stages. The change tendency of antioxidant enzyme activity and MDA level was in line both with soil moisture status and rice yields of different treatments.

Relation between chemical indices of soil and earthworm abundance under chemical fertilization

M. Iordache, I. Borza

Plant Soil Environ., 2010, 56(9):401-407 | DOI: 10.17221/234/2009-PSE

The study intended to establish how the dynamics of earthworms (Oligochaeta: Lumbricidae) changes in soil (abundance, biomass), under conditions of mineral fertilization with nitrogen and phosphorous in four different doses, in a 33-year experimental placement in the west of Romania, in wheat-soybean-maize-barley rotation. The soil indices taken into study were: pH, humus, total nitrogen, phosphorous and potassium. Statistical connections between the studied factors were realized using the dispersion analysis ANOVA and the SPSS Software (Statistical Package for the Social Sciences). The study showed an increase of earthworm abundance and biomass under conditions of chemical fertilization with nitrogen and phosphorous. The highest number of earthworms was recorded in the treatment with the largest dose of nitrogen fertilizer (by 85.85% higher compared to the control treatment). The greatest positive influence on earthworm abundance and biomass was manifested in humus and total nitrogen. The greatest negative influence on earthworm abundance was found in pH factor, while phosphorous content of soil exerted the greatest negative influence on earthworm biomass.

Effect of water stress at different growth stages on quantity and quality traits of Virginia (flue-cured) tobacco type

M.H. Biglouei, M.H. Assimi, A. Akbarzadeh

Plant Soil Environ., 2010, 56(2):67-75 | DOI: 10.17221/163/2009-PSE

A field research was carried out in the years of 2005, 2006 and 2007 in order to determine the effect of irrigation and water stress imposed at different growth stages on quantity and quality traits of Virginia tobacco plants. A randomized complete block design with four treatments and three replications was applied at the Rasht tobacco research station. Treatments were: no irrigation (dryland farming) as the complete water stress (WS0), water stress till the end of flower bud forming stage (WS1), water stress till the end of flowering stage (WS2) and full irrigation (WS3) as control in each cropping season. The combined analysis of variance showed that the effect of water stress on all the traits related to yield, quality traits and all the traits related to yield components except number of leaves, was significant (P < 0.01). The interaction between year and water stress showed that the treatment of WS0 in all three experimental years significantly (P < 0.05) affected the fresh and dry leaf yield, plant height and sugar and nicotine percentage. The comparison of means of three years (average of three years) also revealed that the treatment of WS0 significantly (P < 0.05) affected all of the traits which were related to tobacco quantity and quality except for the number of leaves. Moreover, the level of water productivity in recognition of each water volume unit for three experimental years for the treatments of WS1, WS2 and WS3 were 1.223, 0.873 and 0.594 kg/m3, respectively, in the case of average dry leaf yield. Consequently, the results indicate that with optimizing irrigation application we can reach the higher level of productivity.

Polycyclic aromatic hydrocarbons in soil and selected plants

R. Vácha, J. Čechmánková, J. Skála

Plant Soil Environ., 2010, 56(9):434-443 | DOI: 10.17221/7/2010-PSE

The influence of soil load with polycyclic aromatic hydrocarbons (PAHs) on their contents in selected plants was investigated. A set of experiments was realized in three years. The influence of extreme soil load with PAHs (soil contaminated by floods and sludge application) on their content in plants was observed in a pot trial. A laboratory column extract trial investigated PAHs transfer from the soil into soil solution in different conditions. The results showed that the transfer of PAHs into plants is influenced mainly by chemical characteristics of the substances (the number and position of aromatic nuclei); by soil characteristics (content and quality of soil organic matter) and by plant characteristics (plant species and plant bodies). The roots of tested plants were loaded with PAHs thanks to the transfer of less-nuclei compounds (2-3 nuclei) in soil solution into the roots and thanks to the binding of more nuclei compounds (4-6 nuclei) on organic substances in epidermis and primary bark of roots. These results were confirmed by a laboratory column trial.

Game browse and its impact on selected grain crops

R. Cerkal, K. Vejražka, J. Kamler, J. Dvořák

Plant Soil Environ., 2009, 55(5):181-186 | DOI: 10.17221/381-PSE

This work presents the results of a survey that studied simulated plant browsing by herbivores. In 2004-2006, winter wheat, spring barley, and maize field trials were founded in order to monitor the impact of different levels of defoliation (leaf area reduction) on the yield and grain quality. The defoliation was carried out by means of mechanical removal of plant parts in the early growth stages. Selected qualitative parameters were determined in the harvested grain of wheat and barley. Statistically significant influence of leaf area reduction (LAR) on grain yield (decrease by 4-14%) was found only in maize in 2004. No statistically significant influence of the leaf area reduction on thousand grain weight (TGW) was found in any of the studied crops. The leaf area reduction in barley did not affect grain characteristics; however, it had a statistically significant influence on the quality of wheat grain. Moreover, wheat reduction statistically significantly increased the falling number (by 29-39 s) and decreased SDS test values (by 8-9 ml).

Soil degradation: a problem threatening the sustainable development of agriculture in Northeast China

X.B. Liu, X.Y. Zhang, Y.X. Wang, Y.Y. Sui, S.L. Zhang, S.J. Herbert, G. Ding

Plant Soil Environ., 2010, 56(2):87-97 | DOI: 10.17221/155/2009-PSE

Soil degradation that results from erosion, losses of organic matter and nutrients, or soil compaction are of great concern in every agricultural region of the world. The control of soil erosion and loss of organic matter has been proposed as critical to agricultural and environmental sustainability of Northeast China. This region is bread basket of China where the fertile and productive soils, Mollisols (also called Black soils), are primarily distributed. In this paper, we introduce the importance of Northeast China's grain production to China, and describe the changes of sown acreage and grain production in past decades. This paper also summarizes the distribution, area and intensity of water erosion, changes in the number of gullies and gully density, thickness of top soil layer, soil organic matter content, bulk density, field water holding capacity, and infiltration rates; the number of soil microorganism and main enzyme activities from soil erosion in the region are also summarized. The moderately and severely water-eroded area accounted for 31.4% and 7.9% of the total, and annual declining rate is 1.8%. Erosion rate is 1.24-2.41 mm/year, and soil loss in 1°, 5° and 15° sloping farmlands is 3 t/ha/year, 78 t/ha/year and 220.5 t/ha/year, respectively. SOC content of uncultivated soil was nearly twice that of soil with a 50-year cultivation history, and the average annual declining rate of soil organic matter was 0.5%. Proper adoption of crop rotation can increase or maintain the quantity and quality of soil organic matter, and improve soil chemical and physical properties. Proposed strategies for erosion control, in particular how tillage management, terraces and strip cultivation, or soil amendments contribute to maintain or restore the productivity of severely eroded farmland, are discussed in the context of agricultural sustainability with an emphasis on the Chinese Mollisols.

Response of seed yield and its components of red gram (Cajanus cajan L. Millsp.) to elevated CO2

M. Vanaja, P.R. Ram Reddy, N.J. Lakshmi, S.K. Abdul Razak, P. Vagheera, G. Archana, S.K. Yadav, M. Maheswari, B. Venkateswarlu

Plant Soil Environ., 2010, 56(10):458-462 | DOI: 10.17221/51/2010-PSE

Pigeon pea (Cajanus cajan L. Millsp.) is an important grain legume crop of the semi arid tropics and is a major dietary protein source. The extra short duration cultivar of pigeon pea ICPL 88039 was evaluated at ambient(370 μmol/mol) and twice the ambient (700 μmol/mol) concentrations of CO2 in open top chambers (OTCs). The results showed that the crop recorded a significant positive enhanced response for total biomass, fodder yield, grain yield, number of pods and seeds per plant, test weight and HI at elevated CO2. The ANOVA revealed significant differences in response of the characteristics to CO2 concentrations. Under elevated CO2 the total biomass recorded an improvement of 91.3%, grain yield 150.1%, fodder yield 67.1%. The major contributing components for improved grain yield under elevated CO2 were number of pods, number of seeds and test weight which recorded an increase of 97.9%, 119.5% and 7.2%, respectively. The crop maintained a significant positive increase of harvest index (HI) at elevated CO2 with an increment of 30.7% over ambient values. This increase in HI was due to its improved pod set and seed yield under enhanced CO2 concentration thereby emphasizes this crop for sustained food with nutritional security under climate change scenario.

Morpho-anatomical characterization of root in recurrent selection cycles for flood tolerance of maize (Zea mays L.)

T.C. de Souza, E.M. de Castro, F.J. Pereira, S.N. Parentoni, P.C. Magalhăes

Plant Soil Environ., 2009, 55(11):504-510 | DOI: 10.17221/110/2009-PSE

Changes in root anatomical structures at successive cycles of selection (cycle 1 to cycle 18, alternating) were observed in the study of maize (Zea mays L. cv. Saracura-BRS 4154) capable to survive and produce in temporarily flooded soils; this cultivars was developed by the Maize and Sorghum National Research Center through stratified phenotypic recurrent selection for cultivation wetland soils. Field trial was carried out and flooding of the soil was initiated at the six-leaf stage; the soil was flooded with water (20-cm deep) three times per week. Root sample was collected, fixed, and selected for observation in photon microscope. A gradual increase in the number of aerenchyma, the proportion of vascular cylinder, smaller metaxylem, and phloem and epidermis width, and a decrease in exodermis and cortex were observed in successive selection cycles. Such phenotypic changes impart the flood tolerance ability to this maize cultivar.

Effect of provenance and ploidity of red clover varieties on productivity, persistence and growth pattern in mixture with grasses

S. Hejduk, P. Knot

Plant Soil Environ., 2010, 56(3):111-119 | DOI: 10.17221/164/2009-PSE

In temporary and permanent grasslands, red clover distinctly increases herbage quality and production at low fertilization requirements. Main disadvantage of this species is its insufficient persistence. There are considerable differences in persistence among varieties, which are connected with different adaptability and disease resistance. In this experiment, we assessed the production of dry forage, number of plants and growth differences in eight tetraploid and fourteen diploid varieties grown in mixture with grasses. The highest production of forage for both harvest years was achieved by Czech varieties Spurt and Amos and by Swiss variety Milvus. The lowest forage production was recorded in both years in Swedish one-cut varieties Betty, Jesper and SW Torun. In the second production year, the most yielding was German variety Lucrum, followed by Czech varieties Spurt and Amos. The highest cover in the third production year was reached by Swiss variety Artus (87.8%) while the lowest cover was recorded in Austrian variety Reichersberger Neu (40.0%). Tetraploid varieties exhibited significantly lower contents of dry matter but their productivity and persistence did not differ from diploids. Very suitable for long-term use thus appear Swiss varieties of Mattenklee type (Artus, Milvus), German variety Lucrum and Czech varieties Amos, Spurt and Start.

Phenotypic and alpha-acid content diversity of wild hop populations in Croatia

S. Srečec, V. Zechner-Krpan, V. Petravić-Tominac, A. Čerenak, Z. Liber, Z. Šatović

Plant Soil Environ., 2010, 56(1):37-42 | DOI: 10.17221/130/2009-PSE

An ecogeographical survey of wild hop populations was conducted in the northwest of Croatia in two consecutive years. A total of 121 plants was documented on eight locations. Along with the passport data, the data on three phenotypic traits (no. of leaflets, cone shape, aroma) were gathered during collection, while the content of α-acids in hop cones was determined by lead conductance. Shannon's information index was calculated for each phenotypic trait and was used as a measure of intra- and inter-population diversity. For all analyzed traits, most of the total phenotypic diversity was attributable to differences among plants within populations. The differences in proportions of individuals having a particular trait state between all pairs of populations in the case of leaflet number and cone shapes were non-significant. Four out of 28 pairwise comparisons for aroma were proven significant, indicating the existence of differences in proportions of individuals across populations recorded to have 'typical hoppy', 'fine hop' or 'rough' aroma. No significant differences were observed for α-acids content among populations. Plants exhibiting elongated cone shape had significantly higher α-acids content than those having oval or round cone shapes. Similarly, plants categorized as 'rough' aroma hop cones had the highest content of α-acids compared with those categorized as 'typical hoppy' or 'fine hop aroma' hop cones.

Growth, photosynthesis and antioxidant defense systém in Zn-deficient red cabbage plants

R. Hajiboland, F. Amirazad

Plant Soil Environ., 2010, 56(5):209-217 | DOI: 10.17221/207/2009-PSE

The effect of Zn deficiency was studied in red cabbage (Brassica oleracea L. var. capitata f. rubra) plants grown in nutrient solution under controlled environmental conditions. Zinc starvation affected the number (61%), surface area (72%) and biomass (62%) of leaves more than root biomass (42%). Although chlorophyll fluorescence parameters revealed occurrence of photoinhibition following declined stomatal conductance and reduction of CO2 available at carboxylation sites, photosynthesis apparatus was not damaged seriously under Zn deficiency conditions. Chlorophyll a, chlorophyll a/b ratio, soluble carbohydrates and starch declined but anthocyanins and free phenolics were accumulated under Zn deficiency conditions. Activity of ascorbate peroxidase, catalase and peroxidase enhanced under Zn deficiency conditions, whereas activity of superoxide dismutase declined in leaves but not in roots of Zn-deficient plants. Maintenance of superoxide dismutase activity and malondialdehyde content in roots demonstrated that roots were more protected against reactive oxygen species imbalance under Zn deficiency conditions compared with leaves that was correlated well with the lower sensitivity of roots to low Zn supply.

A molecular evidence for the presence of methylobacterial-type Fe siderophore receptor in Celosia cristata

A. Gholizadeh, B.B. Kohnehrouz

Plant Soil Environ., 2010, 56(3):133-138 | DOI: 10.17221/194/2009-PSE

The presence of efficient iron-uptake bacteria was predicted to be localized as endosymbionts within the leaves of Celosia cristata, a well known iron-rich plant. On the other hand, the symbiotic methylobacterium having a distinctive pink pigmentation was suggested to be more likely in the leaves of pink-colored plants. These considerations were experimented by priming a cDNA fragment containing methylobacterial-type Fe siderophore receptor domain from Celosia leaf cDNA population. Since no detectable homologue was found in plant species sequenced to date, the presence of a Fe-efficient methylobacterium endosymbiosis was reliably predicted in Celosia plant. This is the first report that may lead to the way for future studies on molecular interactions between high iron content pink-colored plants and iron-efficient pink-pigmented bacteria. Corresponding cDNA sequence was submitted to EMBL databases under accession number FM955594.

Effects of high concentrations of soil arsenic on the growth of winter wheat (Triticum aestivum L) and rape (Brassica napus)

Q.J. Liu, C.M. Zheng, C.X. Hu, Q.L. Tan, X.C. Sun, J.J. Su

Plant Soil Environ., 2012, 58(1):22-27 | DOI: 10.17221/311/2011-PSE

Soil arsenic (As) levels are particularly high in parts of China, where wheat and rape are widely grown. Understanding the effects of As concentration on the growth of these two major crops is of significance for food production and security in China. A pot experiment was carried out to study the uptake of As and phosphorus (P), and the soil As bioavailability at different growth stages of wheat and rape. The results indicated that winter wheat was much more sensitive to As stress than rape. Wheat yields were elevated at low rates of As addition (< 60 mg/kg) but reduced at high rates of As concentrations (80-100 mg/kg); while the growth of rape hadn't showed significant responses to As addition. Phosphorus concentrations in wheat at jointing and ear sprouting stages increased with increasing soil As concentrations, and these increases were assumed to contribute a lot to enhanced growth of wheat at low As treatments. Arsenic did not significantly affect P concentrations in rape either. The highest As concentrations in wheat shoot and rape leaf were 8.31 and 3.63 mg/kg, respectively. Arsenic concentrations in wheat and rape grains did not exceed the maximum permissible limit for food stuffs of 1.0 mg/kg. When soil As concentration was less than 60 mg/kg, both wheat and rape could grow satisfactorily without adverse effects; when soil As concentration was 80-100 mg/kg, rape was more suitable to be planted than wheat.

Application of FTIR spectroscopy for evaluation of hydrophobic/hydrophilic organic components in arable soil

Š. Matějková, T. Šimon

Plant Soil Environ., 2012, 58(4):192-195 | DOI: 10.17221/317/2011-PSE

The main aim of this study was to determine the intensity of hydrophobic/hydrophilic components of the soil's organic matter as well as its hydrophobicity. Non-destructive Fourier Transform Infrared (FTIR) spectroscopy was used for the diagnosis and characterization of the basic classes of the chemical groups (hydrophilic and hydrophobic components) from which the organic matter in the soils is formed. Soil samples (depth 0-30 cm) were taken from the topsoil of the 70 sampling sites from the experimental field at Prague-Ruzyne (Czech Republic) during 2007-2009, where a conventional soil tillage technology was used. It was found that the variability of the intensity of the hydrophobic components is greater (27.6%) than that of the intensity of the hydrophilic components (6.2%), which correlated significantly with the Corg (r = 0.58; P < 0.05) and Nt (r = 0.65; P < 0.05) in the soil. It was proven that the soil samples with a higher proportion of coarse grains are more hydrophobic than those with higher proportions of clay. Data about soil hydrophobicity can help to evaluate the soil quality parameters as well as the soil fertility.

Conservation effects on the botanical composition of grass swards in the hilly soils of West Lithuania

D. ZABLECKIENÉ, B. BUTKUTÉ

Plant Soil Environ., 2005, 51(3):137-143 | DOI: 10.17221/3566-PSE

Four conservation methods were compared on grassland unused for 30 years: 1. control (unused grassland); 2. one cut, herbage mass was spread for mulch; 3. one cut, herbage mass was removed; 4. two cuts, herbage mass were removed. Experiments were carried out during 1996-2000 at the Kaltinenai Research Station of the Lithuanian Institute of Agriculture in a hilly region of the Zemaiciai Uplands of West Lithuania, on a hilltop and hill slope. During the experimental period an increase in the number of shoots of each botanical group (grasses, legumes and forbs) were identified in all treatments. The highest increase in the total number of grass shoots was characteristic of the controlled treatment on both parts of the hill. At the end of the conservation period, 38 herb species were identified in the trial. Treatments 1 and 2 were richer in floristic diversity (27-33 species) compared with treatments 3 and 4 (20-25 species). The treatments on the hill slope had a more diverse species composition than those on the hilltop. During the grassland conservation period the content of legumes in the herbage mass increased from 0 to 27.7% in the swards where cut herbage was removed.

Bioprotection against Gaeumannomyces graminis in barley a comparison between arbuscular mycorrhizal fungi

V. Castellanos-Morales, 3, R. Cárdenas-Navarro, J.M. García-Garrido, A. Illana, J.A. Ocampo, S. Steinkellner, H. Vierheilig

Plant Soil Environ., 2012, 58(6):256-261 | DOI: 10.17221/622/2011-PSE

Gaeumannomyces graminis var. tritici causes take-all disease, the most important root disease of cereal plants. Cereal plants are able to form a symbiotic association with soil-borne arbuscular mycorrhizal fungi which can provide bioprotection against soil-borne fungal pathogens. However, the bioprotective effect of arbuscular mycorrhizal fungi against soil-borne fungal pathogens might vary. In the present study we tested the systemic bioprotective effect of the arbuscular mycorrhizal fungi Glomus mosseae, Glomus intraradices and Gigaspora rosea against the soil-borne fungal pathogen Gaeumannomyces graminis var. tritici in a barley split-root system. Glomus intraradices, Glomus mosseae and Gigaspora rosea colonized the split-root system of barley plants at different levels; however, all arbuscular mycorrhizal fungi clearly reduced the level of root lesions due to the pathogen Gaeumannomyces graminis. Our data indicate that some arbuscular mycorrhizal fungi need high root colonization rates to protect plants against fungal pathogens, whereas others act already at low root colonization rates.

Microbial community dynamics and function associated with rhizosphere over periods of rice growth

Q. Hussain, G.X. Pan, Y.Z. Liu, A. Zhang, L.Q. Li, X.H. Zhang, Z.J. Jin

Plant Soil Environ., 2012, 58(2):55-61 | DOI: 10.17221/390/2010-PSE

A field experiment was conducted to illustrate the different degree and dynamics of microbial community structure and function in the rhizosphere across four growing stages (before plantation and three growth stages) using a combination of biochemical (enzyme assay and microbial biomass carbon) and molecular approaches of qPCR and PCR-DGGE (polymerase chain reaction-denaturing gradient gel electrophoresis). Rice plant cultivation promoted higher enzyme activities (invertase and urease), microbial biomass carbon (Cmic), bacterial (16S rRNA) and fungal (ITS rRNA) genes abundances in the rhizosphere compared to unplanted soil. Principal component analyses of PCR-DGGE profile also revealed that structures of bacterial and fungal communities of rice planted soil were well distinct from unplanted soil. Moreover, enzyme activities showed a significant positive correlation with the total microbial biomass in the rhizosphere throughout growth stages of rice plant. Relative fungal: bacterial ratios were significantly higher in rice planted soil compared to unplanted soil, suggesting rice plantation enhanced the fungal community in the rice rhizosphere environment. These results further suggest a significant linkage between the microbial community dynamics and function in the rhizosphere associated with rice plant over time.

Influence of injection nitrogen fertilization on yield and seed composition of winter oilseed rape (Brassica napus L.)

L. Peklová, J. Balík, O. Kozlovský, O. Sedlář, K. Kubešová

Plant Soil Environ., 2012, 58(11):508-513 | DOI: 10.17221/455/2012-PSE

Influence of the nitrogen injection fertilization 'controlled uptake long term ammonium nutrition' (CULTAN) on winter rape yield and seed composition was studied in 2009 and 2010 at two sites with different soil-climatic conditions in the Czech Republic. Two conventional treatments consisted of fertilization using the system of divided doses applied on soil surface. Two CULTAN treatments used injection fertilization with the whole dose of nitrogen applied once in the vegetation period, in early spring at the BBCH 26 stage (6 side shoots detectable). The trial compared conventional and CULTAN treatments. The overall dose of nitrogen was 200 kg N/ha in each treatment. The seed yield in a two-year average was 4.83 t/ha at conventional and 4.80 t/ha at the CULTAN treatment. This difference was not statistically significant. The higher nitrogen content in seed was recorded mainly at CULTAN treatments at the Hněvčeves site in 2009. An inconclusively higher phosphorus content was recorded in winter rape seed fertilized with the CULTAN method at both sites in 2010. Content of K, Ca, Mg and S did not show statistically significant differences between the two treatments during both experimental years. In oiliness no differences between conventional and CULTAN methods were observed.

The effect of different rates and forms of sulfur on seed yield and micronutrient uptake by chickpea

M. Islam

Plant Soil Environ., 2012, 58(9):399-404 | DOI: 10.17221/145/2012-PSE

Field experiments were conducted at two different locations (Barani Agricultural Research Institute Chakwal and farm field Talagang, district Chakwal) for two crop-growing seasons in northern rainfed Punjab, Pakistan to assess the yield and micronutrient uptake of chickpea (Cicer arietinum). The treatments were four combinations of two levels of sulfur (15 and 30 kg/ha) from two sources (gypsum and ammonium sulfate) and a no-sulfur control. Application of sulfur resulted in a significant increase in seed yield up to 17% over control. Ammonium sulfate was a more efficient source of sulfur as compared to gypsum at both the locations. Sulfur application resulted in a significant increase in micronutrient uptake by plant; however effect of sulfur application on soil pH at the end of experiment was not significant. Availability of soil zinc and copper increased with sulfur application at the end of two year experiment. Tissue copper and iron and soil available copper and iron correlated negatively with soil pH. Sulfur should be applied to chickpea grown under rainfed conditions in order to increase seed yield, to improve nutritional composition of product and to enhance efficiency of other fertilizers.

Prediction of crude protein content in rice grain with canopy spectral reflectance

H. Zhang, T.Q. Song, K.L. Wang, G.X. Wang, H. Hu, F.P. Zeng

Plant Soil Environ., 2012, 58(11):514-520 | DOI: 10.17221/526/2012-PSE

Non-destructive and rapid monitoring methods for crude protein content (CPC) in rice grain are of significance in nitrogen diagnosis and grain quality monitoring, and in enhancing nutritional management and use efficiency. In this study, CPC and canopy spectra in rice were measured based on rice field experiment. Key spectral bands were selected by principal component analysis (PCA) method, and the predicted models were built by multiple linear regressions (MLR), artificial neural network (ANN) and partial least squares regression (PLSR). The results showed that there is a significant correlation between CPC content and key spectral bands. The results of prediction for the three models were in order of PLSR > ANN > MLR with correlation values of 0.96, 0.92 and 0.90, respectively, for the validation data. Therefore, it is implied that CPC in rice (grain quality) could be estimated by canopy spectral data.

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