Fulltext search in archive



« advanced mode »

 previous    ...   159   160   161   162   163  164   165   166   167   168   ...    next 

Results 4861 to 4890 of 5716:

The fauna of cambioxylophagous insects on Scots pine trees declined after spells of drought in 2003

J. Foit

J. For. Sci., 2007, 53(7):334-339 | DOI: 10.17221/2079-JFS

The paper deals with cambioxylophagous insects on Scots pine (Pinus sylvestris L.) trees. Research was conducted in forest stands growing on steep slopes on the left bank of the Otava River about 1 km north of Písek. These are nearly unmanaged stands of a special-purpose function with the natural occurrence of Scots pine. In total, twenty standing trees at 60 to 160 years of age that died after the spell of drought in 2003 were analysed. The composition of the community of cambioxylophagous insects was recorded in detail. The frequencies of occurrence of particular insect species were determined. In total, 34 species of cambioxylophagous insects were recorded. The order Coleoptera was quite a dominant group and within the order bark beetles (Scolytidae) and longhorn beetles (Cerambycidae) prevailed. The median of the species developing on one tree was 11. Tomicus piniperda (L.) was markedly the most frequent species with the frequency of occurrence 90%. Based on the composition of the communities of cambioxylophagous insects the potential importance of the insect in the decline of the analysed Scots pine trees was evaluated. Cambioxylophagous insects probably played a secondary role there.

Root systems of forest tree species and their soil-conservation functions on the Krušné hory Mts. slopes disturbed by mining

P. Čermák, F. Fér

J. For. Sci., 2007, 53(12):561-566 | DOI: 10.17221/2167-JFS

The paper describes the root system architecture of the forest tree species Fagus sylvatica L., Quercus robur L., Pinus sylvestris L., Carpinus betulus L., Acer platanoides L., and Alnus glutinosa (L.) Gaertn. at the age of 80-220 years growing on the slopes of the Krušné hory Mts. at the altitude of 330 to 480 m above sea level. These species were influenced by open-pit mining of brown coal as well as by power engineeting. The investigation also involves the determination of soil properties of Ranker Cambisols.

Analysis of the lipid fractions of coffee creamers, cream aerosols, and bouillon cubes for their health risk associated constituents

Lenka Karšulínová, Blanka Folprechtová, Marek Doležal, Jana Dostálová, Jan Velíšek

Czech J. Food Sci., 2007, 25(5):257-264 | DOI: 10.17221/679-CJFS

Fifteen coffee creamers, 10 cream aerosols, and 5 bouillon cubes from the retail market were analysed, principally for their contents of trans-fatty acids that are known to increase the risk of coronary heart disease, and for their contents of 3-chloropropane-1,2-diol (3-MCPD) fatty acid esters that possibly have a bioaccumulation potential. The contents of trans-fatty acids in coffee creamers, cream aerosols and bouillon cubes were in the range of 0.2-32.8%, < LOD - 6.0%, and 0.5-2.1% of total fatty acids, respectively. All samples contained high levels of 3-MCPD fatty acid esters that were determined after releasing the free 3-MCPD by methanolysis. The 3-MCPD levels in coffee creamers, cream aerosols, and bouillon cubes were in the range of 130-730 µg/kg (540-4480 µg/kg fat), 50-730 µg/kg (220-2880 µg/kg fat), and 380-670 µg/kg (2650-4840 µg/kg fat), respectively. The results showed that the refined and hydrogenated oils may represent a certain risk. The highest levels of 3-MCPD esters were found in a sample of refined palm oil (4170 µg/kg). Currently, there is no information available on how these 3-MCPD esters are metabolised, to which extent they are hydrolysed or biosynthesised in the body, to which extent they are deposited in tissues, and how they influence the properties and functions of tissues (if they really do it).

Effect of treated wastewater on soil chemical and physical properties in an arid region

J. Abedi-Koupai, B. Mostafazadeh-Fard, M. Afyuni, M.R. Bagheri

Plant Soil Environ., 2006, 52(8):335-344 | DOI: 10.17221/3450-PSE

This study was carried out to investigate the effect of treated wastewater on soil chemical and physical properties. Field experiment was conducted in Borkhar region in Isfahan province in central Iran with two water treatments of wastewater and groundwater under sprinkler and surface irrigation systems for three crops of sugar beet, corn and sunflower. Soil samples were collected to 120 cm depth to determine concentration of lead (Pb), manganese (Mn), iron (Fe), cadmium (Cd), nickel (Ni), cobalt (Co), copper (Cu) and zinc (Zn). Irrigation systems had no significant effect on extractable heavy metals in soil. The accumulation of Pb, Mn, Ni and Co in the soil increased significantly in the wastewater treatment as compared to the groundwater treatment. The accumulation of Pb, Mn, Ni, Co, Cu and Zn decreases with the soil depth. Treated wastewater showed no effect on the increase of Fe, Cd, Ni, Cu and Zn during growing season. The irrigation system had a significant effect on infiltration rate, bulk density and total porosity. Under sprinkler irrigation system the infiltration rate increased significantly

Chromosomal rearrangements in Arabidopsis mutants revealed by repeated FISH

P. Mokroš

Plant Soil Environ., 2007, 53(7):325-328 | DOI: 10.17221/2206-PSE

The stability of plant nuclear genome is a necessary condition for the faithful transmission of genetic information through cell lineages. When DNA damage occurs due to various impairments, cells start a number of repair processes including ligation of broken chromosomes. As a result, dicentric chromosomes can be formed. Dicentrics are easily detectable as anaphase bridges during following mitosis. Using Arabidopsis as a model plant, we developed a sensitive cytogenetic assay to identify specific chromosomal rearrangements. Here we show Arabidopsis tert-/- and atm-/- mutants and their chromosome rearrangements and fusions analysed by fluorescence in situ hybridization (FISH). The method is based on successive rounds of FISH with chromosome-specific probes and the comparison of resulting FISH images.

Effect of interactions between nickel and other heavy metals on the soil microbiological properties

J. Wyszkowska, E. Boros, J. Kucharski

Plant Soil Environ., 2007, 53(12):544-552 | DOI: 10.17221/2190-PSE

A pot greenhouse experiment was performed to determine the effect of contamination with nickel interacting with other heavy metals on the microbiological properties of soil. The study was conducted on samples of soils classified under natural conditions as typical Eutric Cambisol developed from heavy loamy sand and typical Eutric Cambisol developed from light silty loam. Soil material was contaminated with nickel in the amount of 50 and 200 mg Ni2+/kg. The treatments with 200 mg Ni2+/kg were additionally contaminated with other heavy metals (Zn2+, Cu2+, Pb2+, Cd2+, Cr6+), in the amount of 50 mg/kg soil. The following treatments, in which the soil was contaminated with heavy metals applied alone or in combinations, were compared in the study: Ni, Zn, Cu, Pb, Cd, Cr, NiZn, NiCu, NiPb, NiCd, NiCr, NiZnCu, NiZnPb, NiZnCd, NiZnCr, NiZnCuPb, NiZnCuCd, NiZnCuCr, NiZnCuPbCd, NiZnCuPbCr, NiZnCuPbCdCr. The experiment was carried out in four replications. A microbiological analysis was performed on days 28 and 56. The tested crop was oat. It was found that the impact of particular heavy metals on microbiological properties of soils depended on their type, interactions between nickel and zinc, copper, lead, cadmium and chromium (VI), date of analysis and soil species. Soil contamination with heavy metals reduced the population size of Azotobacter spp. The counts of other microbial groups, i.e. copiotrophic bacteria, spore-forming copiotrophic bacteria, oligotrophic bacteria, spore-forming oligotrophic bacteria, ammonifying bacteria, nitrogen immobilizing bacteria, cellulose-decomposing bacteria, Arthrobacter spp., Pseudomonas spp., actinomyces and fungi, showed varied susceptibility to heavy metals.

Inflorescence blast and flower bud abnormalities of Spiraea × vanhouttei and their causes

Václav Kůdela

Czech J. Genet. Plant Breed., 2007, 43(4):135-143 | DOI: 10.17221/1898-CJGPB

In ornamental gardening, Spiraea × vanhouttei is a frequently planted spirea species in the Czech Republic. In 2003, there arose a suspicion of possible occurrence of fire blight caused by Erwinia amylovora on spirea shrubs in Prague and its environs. This suspicion was disproved for a certainty. The absence of the fire blight pathogen in symptomatic spirea plants stimulates a further effort to tackle the problem of a cause of conspicuous fire blight-like symptoms or inflorescence blast occurring on some spirea shrubs. The subject of this paper is: (i) to describe symptoms, incidence and severity of inflorescence blast, bud and flower abnormalities occurring in Spiraea × vanhouttei shrubs; (ii) to find out differences in the occurrence of blasted inflorescences between Spiraea species and cultivars with the intention of verifying the hypothesis that the blast inflorescence and sterility of some spirea species are associated with hybrid species. Symptoms of inflorescence blast are every growing season. No seed is produced by blasted inflorescences. Besides inflorescence blast, aborted floral buds appeared sporadically on a small scale. Spirea species were split into four categories according to the incidence of blasted inflorescences. Out of 52 species evaluated, 10% showed no or scarce incidence, 52% medium incidence, 27% high incidence and 11% very high incidence. The scarce incidence of blasted inflorescences was connected with the high seed production. And vice versa, very high incidence of blighted inflorescences was closely connected with no or low seed production or with high incidence of sterility. Fifteen out of the evaluated spirea species are the result of hybridization. These hybrids occur in each of the four categories of spirea species distinguished by the incidence of blasted inflorescence. However, it is remarkable that the highest incidence of hybrid spireas occurs in the category with the highest incidence of blasted inflorescence (83.33%). In the remaining three categories of spirea species, the proportion of hybrids ranged from 18 to 21%. It might indicate some connection of spirea hybrids with sterility.

Effect of weaning system on lamb growth and commercial milk production of Awassi dairy sheep

S. Dikmen, I.I. Turkmen, H. Ustuner, F. Alpay, F. Balci, M. Petek, M. Ogan

Czech J. Anim. Sci., 2007, 52(3):70-76 | DOI: 10.17221/2357-CJAS

To determine the effect of weaning system on Awassi sheep milk production and lamb growth, 68 Awassi ewes and their lambs (n = 104) were assigned to one of the following treatment groups a) after 3 days from birth (MIX), ewes were separated from their lambs during the evening for 15 h and milked once daily in the morning, and their lambs were allowed to suckle for 9 h during the day or b) ewes were not milked and suckled by their lambs (DY60) during the first 60 days of lactation. Ewes and their lambs were assigned to the groups according to ewe's age, parturition date, sex of the lamb and birth type. All lambs were weaned at 60 days of age and the ewes were milked twice daily. Milk yield was recorded fortnightly and milk fat composition was recorded monthly. The birth weight of lambs was recorded in the first 2 hours and they were weighed fortnightly until 240 days of age. Average lactation lengths (including suckling and milking) in MIX and DY60 group were similar (171.21 ± 5.40 and 168.36 ± 4.87 days, respectively). Differences between MIX and DY60 group in commercial milk yield (103.25 ± 7.93 and 63.59 ± 5.41 kg, respectively) and milk fat yield (5.88 ± 0.64 and 3.62 ± 0.31 kg, respectively) were highly significant (P < 0.001). Growth performance of lambs was similar in both groups (P > 0.05), however, male lambs were heavier and grew faster than female lambs until weaning (P < 0.05) and 90 days of age (P < 0.001). The effect of birth type at 210 days of age for the female lambs in MIX group was found to be statistically significant (P < 0.05) and the mean weight of single born female lambs was 40.39 ± 1.27 kg, and 41.09 ± 1.22 kg for twin born female lambs. The effects of ewe's age for female lambs in MIX and DY60 group and birth type for the lambs in DY60 group were insignificant (P > 0.05). These results show that Awassi lambs can be successfully reared in MIX suckling system and ewes produce more commercial milk than in the traditional rearing system (DY60), which offers a potential increase in economic return for Awassi sheep producers.

Supplemental wheat bran and microbial phytase could replace inorganic phosphorus in laying hen diets

J.H. Yao, J.C. Han, S.Y. WU, M. XU, L.L. Zhong, Y.R. Liu, Y.J. Wang

Czech J. Anim. Sci., 2007, 52(11):407-413 | DOI: 10.17221/2321-CJAS

An experiment was conducted to determine effects of wheat bran (WB) phytase on production performance and nutrient utilization in laying hens. Three hundred and seventy-five Lohmann hens at 32 weeks of age were randomly allotted to treatments of fifteen hens per pen with five pens per treatment. Five experimental diets were formulated. Diet one (control) contained 0.19% inorganic phosphate (Pi) from dicalcium phosphate. On the basis of diet 1, diet 2 and 3 were formulated to contain WB 5% and 10%, respectively. In diet 4 and 5, the WB was fixed at the level of 10% with Pi level adjusted to 0.14% in diet 4 and completely replaced with 500 U/kg microbial phytase in diet 5. The results showed that treatment three improved egg yield (P = 0.142), feed conversion ratio (FCR) (P = 0.011), utilization of crude protein (CP) (P = 0.060) and total phosphorus (tP) (P < 0.001), and serum Pi concentration (P = 0.016) compared with the control. Ten percent of WB replacing 0.05% Pi did not influence either egg yield or nutrient utilization. Compared with the control, treatment five improved FCR (P = 0.011) and utilization of CP (P = 0.060) and tP (P < 0.001), but did not influence either performance or serum parameters. The current study suggests that wheat bran could be used successfully in laying hen diets and wheat bran and microbial phytase supplemented together could replace inorganic phosphate completely.

Agribusiness in the Turkish ekonomy

N. Demirbas

Agric. Econ. - Czech, 2007, 53(5):224-229 | DOI: 10.17221/1444-AGRICECON

Agribusiness has made many important contributions to the Turkish economy. These conributions related to meeting of the nation's food demand, creating added value, increasing and diversifying exports and increasing employment. While the relative importance of the Turkish agriculture sector decreases over the years, in the economy, agribusiness still preserves its place and developments. This paper assesses the contribution of agribusiness to the economy during the period 1994-2004, in terms of production and export values and the firms working in this area. Within the agribusiness, the most stable and best-developed industries were food and textile in the period concerned. Changes in the economy influences agribusiness but the basic problem that affects it is development is the integration with the agricultural sector. That is the downstream relations, which is not the desired level at all.

Competitiveness of the Finnish Agriculture after ten years in the EU

K. Tomšík, E. Rosochatecká

Agric. Econ. - Czech, 2007, 53(10):448-454 | DOI: 10.17221/924-AGRICECON

Finnish agriculture changed radically with the EU joining in 1995. The commitment of the Common Agricultural Policy (CAP) led to unprecedented changes in economic environment - in agriculture as in processing industry. Finland lost the possibility to regulate the original price level of agricultural products supported by the national border protection and export subsidies. Prices guaranteed by the EU are much lower today than before the EU-membership. Recently, Finland has evaluated ten years being an EU member. Despite its competitive disadvantage, given mostly by unfavourable production conditions, Finnish agriculture has not lost within the competitive environment of the single market and it has tried to take advantage of the opportunities offered by the CAP. The article recapitulates the ten year effort of Finnish agriculture to ensure the competitiveness within the EU single market.

The decomposition of wood mass under conditions of climax spruce stands and related mycoflora in the Krkonoše MountainsOriginal Paper

L. Janovský, A. Vágner, J. Apltauer

J. For. Sci., 2002, 48(2):70-79 | DOI: 10.17221/11857-JFS

The mycoflora was investigated under the conditions of climax spruce stands in the Krkonoše Mountains in relation to wood decomposition. The areas under observation have been affected more or less by air pollution since the eighties. The average mass of deadwood found on the plots is 124 m3 per ha - the mass of fallen trunks is about 32 m3 per ha, mean value from total average. About 128 species of macrofungi were identified that besides others included 43 species of wood-decaying fungi. Also 54 mycorrhizal species were identified. Among the mycorrhizal fungi about 10 species were dominant, such as Laccaria laccata (Scop.: Fr.) Cooke, Lactarius helvus Fr., Lactarius mitissimus Fr., Lactarius rufus (Scop.) Fr., Russula emetica (Schaeff.: Fr.) Pers. and Russula ochroleuca Pers. etc. Concerning the volume of decomposed wood on monitored plots in climax spruce stands, the prevalent wood-decaying fungi are brown rot fungi. The proportion of brown rot fungi in wood decomposition is 60-95% of deadwood mass on the plots of climax spruce stands. A dominant species is Fomitopsis pinicola (Sw.: Fr.) P. Karst. causing the brown rot. Concerning the group of white rot fungi, the most important is Stereum sanguinolentum (Alb. & Schw.: Fr.) Fr., participating by 17% in wood decomposition on plots damaged by deer.

Tests for the presence of koi herpesvirus (KHV) in common carp (Cyprinus carpio carpio) and koi carp (Cyprinus carpio koi) in the Czech Republic

D. Pokorova, V. Piackova, A. Cizek, S. Reschova, J. Hulova, M. Vicenova, T. Vesely

Vet Med - Czech, 2007, 52(12):562-568 | DOI: 10.17221/1883-VETMED

An outbreak of koi herpesvirus (KHV) infection associated with high mortality of common and koi carp was recorded in the USA and Israel in 1998. At present, this disease is viewed as one of the most significant factors that can adversely affect common and koi carp breeds. The disease has spread worldwide including European countries neighbouring with the Czech Republic (CR), i.e. Germany, Poland, and Austria. To monitor the situation in the CR, samples were collected from a total of 138 common and koi carps in seven and eight locations in CR respectively, and were examined between 2005 and 2006. Locations owned by the major producers of common and koi carp were selected with respect of potential occurrence of the KHV virus. No records of increased mortality and morbidity were noticed there. Preferentially carps with non-specific symptoms of disease were sampled, often with isolated skin erosions. To obtain detailed picture about health condition of examined fish the bacteriological and haematological examinations were accomplished. The next part of the examined samples were carp and koi carp for export from professional breeders, imported koi carp and fish from breeds with increased mortality (45 and 21 fish in 2005 and 2006, respectively) The only virological testing was done in this case. The culture and PCR method, according to Gilad et al. (2002) showed negative results for virus KHV in all years. Retrospective investigation by PCR method according to Bercovier et al. (2005) showed positivity in five locations in 2005. In 2006, KHV virus was not detected in any of the selected locations. The aim of our study was to find out the presence/absence of KHV in selected locations and potential correlation of virological, bacteriological and haematological findings. The results of first testing for presence of koi herpesvirus indicates the necessity of regular KHV monitoring in the Czech Republic in the next period.

Utilization of digital photogrammetry in forestry mapping

Š. Žíhlavník, F. Chudý, M. Kardoš

J. For. Sci., 2007, 53(5):222-230 | DOI: 10.17221/2176-JFS

At present, photogrammetric interpretation of aerial images is a dominant method of forestry mapping. In the last years, transition from analogue to digital photogrammetry has been distinct. Digital photogrammetry enables to achieve workflow effectivity, and so to decrease the final product costs. The objective of the submitted paper was to evaluate the availability of digital photogrammetry for the forestry mapping rationalization. Digital aerotriangulation using the ImageStation SSK system brings more accurate results without requirements for the use of a larger amount of control points. The results also demonstrated the use of colour infrared aerial images, and also black and white aerial images at the scale 1:15,000 for the orthoimage creation in the forestry mapping department. Compared with the black and white aerial images, the colour infrared images have an essentially more interesting content, mainly from the qualitative aspect, which shifts them to use in many forestry disciplines (mostly for determination of the health conditions of forests stands, …), in combination with the remote sensing of the Earth and GIS (Geographic Information Systems).

Possibilities of using rooted cuttings of European beech (Fagus sylvatica L.) for stabilisation of forest ecosystems

A. Jurásek

J. For. Sci., 2007, 53(11):498-504 | DOI: 10.17221/2021-JFS

Vegetative propagation of forest tree species is of great importance not only for breeding programmes but also for the conservation of valuable populations of tree species. Important is also a possibility of improving the genetic quality of established stands. Beech is a tree species that can substantially increase the stability of forest ecosystems. Minimal information is available about the ontogenesis of rooted cuttings of beech in forest stands for the time being. In our experiments that were gradually established since 1993 we acquired the first significant results of the evaluation of health status, phenological phenomena and growth of these plants. Our findings indicate that it is possible to use rooted cuttings as an element stabilising man-made forest stands including the transferred genetic quality. The evaluation of the 2nd generation rooted cuttings of beech also provided positive results.

Research, conservation and utilisation of plant genetic resources and agro-biodiversity enhancement - Contribution of the Research Institute of Crop Production Prague-Ruzyně

L. Dotlačil, Z. Stehno, I. Fáberová, A. Michalová

Czech J. Genet. Plant Breed., 2002, 38(1):3-15 | DOI: 10.17221/6106-CJGPB

Activities on plant genetic resources in the Czech Republic are concentrated in the National Programme on Conservation and Utilisation of Plant Genetic Resources. Eleven institutions maintain 51,000 accessions, of which 17.3% belong to vegetatively propagated species. Research Institute of Crop Production (RICP) Prague has the responsibility for the coordination of the Programme; it holds more than half of all accessions in collections of genetic resources, runs the national information system and provides long-term storage for all seed-propagated species. All Czech collections are fully documented in passport data. Evaluation data (based on National descriptor lists for 29 crops) are available for 33% of the accessions. Much work is currently spent to the description and evaluation of collections, to facilitate their utilisation in breeding and agricultural practice. Also collecting missions on the Czech territory, conservation and monitoring of valuable resources maintained in situ contributeto the maintenance and evaluation of local resources. Landraces are considered a valuable part of the collections. Suitable ways of "on farm" conservation are investigated for selected accessions, to support their utilisation in agricultural practice and to enrich the existing diversity of crops and cultivars. Cultivars and landraces of neglected crops (buckwheat, millet, hulled wheat species) were successfully used to enrich the agro-biodiversity and for specific purposes of human nutrition. Close collaboration with producers (often organic farms) and processing industry has been established. Selected alternative crops and catch crops were studied as potential new crops.

The role of Fe- and Mn-oxides during EDTA-enhanced phytoextraction of heavy metals

M. Komárek, P. Tlustoš, J. Száková, V. Chrastný, J. Balík

Plant Soil Environ., 2007, 53(5):216-224 | DOI: 10.17221/2203-PSE

In several cases ethylenediaminetetraacetic acid (EDTA) proved to be an efficient mobilising amendment during chemically enhanced phytoextraction of heavy metals. The presence of Fe-(hydr)oxides and their dissolution after the addition of EDTA can limit the phytoextraction of the targeted heavy metals due to the high stability of the formed Fe(III)EDTA complexes. This study has focused on the influence of Fe- and Mn-oxides and hydroxides dissolution on heavy metal uptake by Zea mays in a two-year EDTA-enhanced phytoextraction process. Incubation experiments and speciation modelling proved the increased concentrations of Mn and Fe through the dissolution of Mn-and Fe-(hydr)oxides. Furthermore, increased Fe and Mn accumulation was observed in maize plants after the second year of the phytoextraction process. Therefore, the presence of Mn- and especially Fe-(hydr)oxides proved to be a limiting factor during EDTA-enhanced phytoextraction of heavy metals from contaminated soils.

Chromosome walking with BAC clones as a method of genome mapping

Z. Kubát

Plant Soil Environ., 2007, 53(10):447-450 | DOI: 10.17221/2198-PSE

Current sequencing projects are often based on random sequencing of genomic libraries followed by contig assembly by means of bioinformatics tools. This approach is convenient for whole genome sequencing projects. Chromosome walking described here is suitable for mapping and sequencing of short genomic regions in species where whole genome sequencing is not possible or for cloning gene from its closest known marker. This method is based on searching for overlapping BAC clones specific for the genomic region of interest.

Faba bean (Vicia faba L.) breeding for resistance to anthracnose (Ascochyta fabae Speg.) in the Czech Republic

Michal Ondřej, Igor Huňady

Czech J. Genet. Plant Breed., 2007, 43(2):61-68 | DOI: 10.17221/1909-CJGPB

In 2003-2005 faba bean accessions were evaluated in laboratory and field inoculation tests with a mixture of differently virulent isolates for susceptibility to anthracnose caused by the fungus Ascochyta fabae Speg. All tested commercial faba bean cultivars, both colour and white flowering, were found to be susceptible or highly susceptible. The highest level of resistance was found only in declared sources of resistance: 29H, L-8 and Petra. Segregation of F2 plants derived from the cross of cultivar Merlin (susceptible, white flowering) with line Petra (resistant, colour flowering) was observed. The plants were moderately susceptible to highly susceptible. This finding indicates a multigenic character of resistance. Repeated selection cycles with the selection of resistant plants in F2 and F3 generations were performed. In the F4 generation, colour flowering lines with a high level of resistance, nearly at the same level as in line Petra, were obtained. In comparison with the parental cultivar Merlin an increase in the resistance of selected white flowering lines was proved. Resistance will be increased/stabilized in further repeated selection cycles.

Effect of soil applied herbicides and depth of sowing on common cocklebur (Xanthium strumarium L.) and maize (Zea mays L.) emergence and early growth

Zvonko Pacanoski, Tasko Kostov, Gordana Glatkova, Branislav Knežević

Plant Protect. Sci., 2007, 43(3):117-121 | DOI: 10.17221/2246-PPS

Greenhouse trials were conducted during 2005 to investigate the effect of six soil applied herbicides on common cocklebur (Xanthium strumarium L.) sowed at a depth of 4 cm and 7 cm, and determine the potential injury to maize by the herbicides and the influence of sowing depths. The efficacy of all herbicides was high, regardless of sowing depth and, generally, the coefficient of efficacy ranged from 86.3% to 100.0%. Most of the herbicides had no significant phytotoxic effect on maize plant density/container, height and fresh weight of maize. Exceptions were Atranex-90WDG and Cyatral-SCZ, which caused serious injury to maize (33% and 37%, respectively) if seeded at a depth of 7 cm, and significantly reduced height and fresh weight of the plants.

INDEX (VOLUME 53)

editors

Res. Agr. Eng., 2007, 53(4):188-190 | DOI: 10.17221/1961-RAE

Land market and e-services in Bulgaria

D. Stoyneva

Agric. Econ. - Czech, 2007, 53(4):167-172 | DOI: 10.17221/868-AGRICECON

Bulgaria faced and still is facing many challenges in the accession process to the EU. Free movement of capital, and especially the development of the land market, is one of them. Although the progress is made, the market is still developing and the land prices are still below the average prices in EU. There are different reasons for this: very fragmented land after the restitution process, chaotic transactions, lack of bank credits for agricultural purposes, unrealistic expectations after the accession to the EU, etc. The land lease continues to be the preferred way for land cultivation instead of buying of land. All those problems are studied in the current paper. A concept for e-service that could contribute to solving the problems is introduced; relevant e-services are summarized and a particular solution is presented that uses results of the eTen project Bizmap.net. It is described how this solution could be used in the Bulgarian land market.

Commercial phenotypic tests (API 20E) in diagnosis of fish bacteria: a review

N. Topic Popovic, R. Coz-Rakovac, I. Strunjak-Perovic

Vet Med - Czech, 2007, 52(2):49-53 | DOI: 10.17221/2058-VETMED

The available data concerning rapid identification of fish bacteria via commercial phenotypic tests demonstrate that there is no agreement regarding the choice of the tests. However, API 20E, an identification system for Enterobacteriaceae and other non-fastidious Gram-negative rods developed for clinical specimens, seems to be increasingly used for the identification of fish pathogens. In this review, adaptation of API 20E for fish bacterial isolates and its distinctiveness for fish bacteria was assessed. Some strains are wrongly identified because they are not included in the database of API 20E system. API 20E reactions should be compared with the diagnostic schemes based on reactions in conventional phenotypic tests. Due to their significance for fish health and impact on the aquaculture, and because of the need for their rapid identification, some important fish bacteria should be included in the API 20E system, such as Yersinia ruckeri, Edwardsiella ictaluri, Vibrio anguillarum.

The root-plant ratio changes in the first growing periods of wild cherry (Prunus avium L.) plantations

I. Kupka

J. For. Sci., 2007, 53(3):113-118 | DOI: 10.17221/2147-JFS

The root-plant ratio is one of the important parameters for planting stock quality. We suppose that the ratio is one of the driving variables for the growth performance of new plantation in the forest. The study summarises data on the volume of major parts of 4 years old wild cherry trees. An allometric analysis of different parts of plants in relation to the growth performance of wild cherry trees was done. The results show a close positive relationship between the volume of the whole root system and aboveground biomass. The same is true of the fine root proportion in the root system. Data also document that the efficiency of root system is not decreasing during the root development - at least in the investigated period. The same results were obtained for fine root efficiency. Data confirm the importance of the root-plant ratio for the growth performance of new plantation in the forest provided that harmful factors are not at a limiting level.

The fluctuation of copper content in oilseed rape plants (Brassica napus L.) after the application of nitrogen and sulphur fertilizers

J. Balík, D. Pavlíková, P. Tlustoš, J. Černý, M. Jakl

Plant Soil Environ., 2007, 53(4):143-148 | DOI: 10.17221/2309-PSE

The influence of N-S fertilizers on the copper content in the inter oilseed rape plants was studied in field experiments. The evaluation involved two treatments of a single rate for the first spring fertilizer application with 100 kg N/ha in the AN treatment (nitrochalk) and 100 kg N/ha + 50 kg S/ha in the ANS treatment (ammonium nitrate and ammonium sulphate). A positive influence of the ANS fertilizer on the copper contents in different parts of plants was determined. The highest Cu concentrations were determined in the leaves and inflorescences, the lowest ones occurred in the stem. The concentration of Cu ranged within the interval of 1.56-8.75 mg Cu/kg of dry matter depending on the growth period and the part of the plant. No differences in copper content were determined in the seeds of individual treatment. The highest uptake in the above-ground parts of the plants was recorded in the green pod period and amounted to 57.4 g Cu/ha for the ANS treatment.

Effect of phosphoric fertilizers as a source of sulphur on malt barley total and technological grain yields

J. Potarzycki, W. Grzebisz

Plant Soil Environ., 2007, 53(9):395-402 | DOI: 10.17221/2289-PSE

Malt barley production requires a technology increasing nitrogen use efficiency, because of a high sensitivity of barley total grain yield and quality parameters to external growth factors. In the conducted study an effect of two P fertilizers on the background of N application on total and technological grain yields were studied. The highest total grain yield was harvested on plots fertilized with 60 kg N/ha, irrespective of the P fertilizer type. However, the technological grain yield showed a high year-to-year variability; the highest was recorded in 2001 on the plot fertilized with 60 kg N/ha and the P-PAPR fertilizer. The N and S concentrations and N:S ratios in immature grains at harvest were used to evaluate both yield types. Nitrogen concentration in the final total yield allowed making yields prognosis with the highest probability. The maximum yields of technological malt barley were attainable provided that total S concentration in immature grains at harvest was above 0.23% and the N:S ratio was narrower than 8.0.

Evaluation of the efficacy of protectants against cowpea bruchids (Callosobruchus maculatus (F.)) on cowpea seeds (Vigna unguiculata (L.) Walp.)

George B. Swella, Deus M. K. Mushobozy

Plant Protect. Sci., 2007, 43(2):68-72 | DOI: 10.17221/2256-PPS

A laboratory experiment of a completely randomised design and replicated four times evaluated the effectiveness to control the bruchid, Callosobruchus maculatus in cowpea by the synthetic insecticide Actellic dust, and by the natural protectants ash, coconut oil, powdered cloves and black pepper. The data collected included the number of damaged and undamaged seeds, weight of damaged and undamaged seeds and the number of live and dead bruchids. Seeds treated with Actellic dust and black pepper powder had significantly low percentages of damaged seeds. Black pepper powder and coconut oil showed good potential in protecting cowpea against bruchid damage.

Repeated administration of different hormonal preparations for artificial propagation and their effects on reproduction, survival and blood biochemistry profiles of female tench (Tinca tinca L.)

J. Kouřil, M. Svoboda, J. Hamáčková, P. Kaláb, J. Kolářová, A. Lepičová, M. Sedova, L. Savina, P. Moreno Rendón, Z. Svobodová, T. Barth, B. Vykusová

Czech J. Anim. Sci., 2007, 52(6):183-188 | DOI: 10.17221/2315-CJAS

The aim of the study was to compare physiological statuses of stripped and not stripped tench females with ovulation induced by GnRHa or carp pituitary extract (CPE). The comparison was based on selected biochemical stress indices (cortisol, glucose), condition (TP, TGA), and cell membrane characteristics (ALT, AST, CK). In the first and in the second year, 37 and 29 tench females were monitored, respectively. No differences in the values of biochemical parameters in either period were found between the two groups of stripped female tench whose ovulation was induced by GnRHa and CPE, respectively. No significant differences in TP, TGA, ALT, AST and CK values were found between the groups of stripped and not stripped females with ovulation induced by GnRHa or CPE. Different values were found in stress indices, specifically in glucose concentrations. A significant increase (P < 0.01) in glucose concentrations was found in tench females immediately after stripping and, in not stripped females, about 48 hrs after ovulation induction. Both artificial stripping and the inability to release eggs are important stress factors for female tench.

Developmental trends of world agriculture

V. Jeníček

Agric. Econ. - Czech, 2002, 48(11):519-530 | DOI: 10.17221/5363-AGRICECON

Investigations of suitable pollinator for 0900 Ziraat sweet cherry cv.: pollen performance tests, germination tests, germination procedures, in vitro and in vivo pollinations

F. Tosun, F. Koyuncu

Hort. Sci. (Prague), 2007, 34(2):47-53 | DOI: 10.17221/1851-HORTSCI

The objective of this study was to determine suitable cultivars to be used as pollinators for 0900 Ziraat. 0900 Ziraat was used as a female cultivar; Bigarreu Gaucher, Bing, Noble, Starks Gold, Stella, Van, and Vista were used for pollination in the experiments. Starks Gold had the highest values in terms of anther number, average number of pollens per anther, number of pollen per flower and the morphological homogeneity. The pollen viability rates showed significant differences according to stain tests. In vitro pollen germination in 0.5% agar + 15% sucrose + 5 ppm boric acid medium increased with increasing incubation period, and the highest germination was obtained after 48 hours for all cultivars. In orchard trials parallel to pollen tube growth experiments in the laboratory, 0900 Ziraat × Starks Gold combination gave the best fruit set results.

 previous    ...   159   160   161   162   163  164   165   166   167   168   ...    next