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Results 4411 to 4440 of 4875:

Effect of long-term storage on induced photon emission of boar spermatozoa

P. Gogol, B. Szczęśniak-Fabiańczyk

Czech J. Anim. Sci., 2006, 51(2):61-65 | DOI: 10.17221/3910-CJAS

Ultraweak photon emission measurements were found to be a useful tool for investigating the influence of stress factors on cells. In the present study, induced photon emission of boar spermatozoa was investigated using a luminometer during a 12-day storage at 15°C in Biosolwens extender. It was shown that the day of storage had a significant effect on some photon emission parameters. During storage, a significant increase in the Integral, Peak max. and Slope max. parameters and a decline in the T.-half (fall) parameter were observed. A significant correlation was observed between photon emission parameters and sperm motility. In conclusion, the results of the present study indicate that the measurement of induced photon emission can be an alternative, sensitive and relatively simple method for assessing the effect of preservation on oxidative damage to boar spermatozoa.

Factors contributing to the incidence and prevalence of lameness on Czech dairy farms

I. Dembele, M. Špinka, I. Stěhulová, J. Panamá, P. Firla

Czech J. Anim. Sci., 2006, 51(3):102-109 | DOI: 10.17221/3916-CJAS

Twenty-four Czech dairy farms were visited to record lameness prevalence and to identify factors associated with high lameness prevalence at the farm level and/or increased lameness risk at the level of individual cows. All cows were checked for lameness and forty cows per farm were examined for overgrown claws, body dirtiness and skin lesions. The farm environment was scored between 1 (excellent) to 5 (very poor) in three different aspects: floor slipperiness, cow care quality, and housing quality. Data on hoof trimming schedules were obtained from farm managers. Lameness prevalence on farms was in a wide range from 6% to 42% (median 22%). At the farm level, floor slipperiness and poor animal care were associated with high lameness prevalence (Spearman correlations, P < 0.05), and the proportion of cows with overgrown claws tended to be associated with it (P < 0.10). The reported time schedules of hoof trimming (continuous trimming applied or not; and time elapsed since the whole herd was trimmed) were unrelated to either the prevalence of overgrown claws or the prevalence of lameness. Within farms, cows with overgrown claws and dirty cows were at an increased risk of being lame (multiple logistic regression, P < 0.05) and cows with skin lesions tended to be more lame (P < 0.10). The risk of lameness had an inverted U-shape dependence on age (P < 0.05), with cows at 7-8 years of age being the most endangered by lameness. We conclude that there is a large potential for lameness reduction on some Czech dairy farms through improving the cow care and reducing floor slipperiness, and that within farms, cows with overgrown claws and also dirty cows and cows with skin lesions should be given special attention since they are more likely to get lame.

Carcass and meat quality in Brown fattened young bulls: effect of rearing method and slaughter weight

A. CERDEÑO, C. Vieira, E. Serrano, A.R. Mantecón

Czech J. Anim. Sci., 2006, 51(4):143-150 | DOI: 10.17221/3921-CJAS

Three groups of Brown fattened young bulls were studied, comparing the effects of rearing method (suckled vs. bucket reared) and of slaughter weight (400 vs. 480 kg). Suckled animals had higher fatness scores (2.2 vs. 1.3), more dissectible fat (14.5 vs. 9.1%), and higher intramuscular fat content (7.8 vs. 4.6%DM), accompanied by better scores in sensory tenderness (5.2 vs. 3.8) than did the bucket-reared ones. Animals slaughtered at a heavier weight showed a higher dressing percentage (57.5 vs. 53.8%), conformation score (9.2 vs. 6.2), and fat content (fatness score, dissectible fat and intramuscular fat). The meat from animals in the heavier group had lower a* (12.4 vs. 14.2) and higher b* (10.8 vs. 12.9) indexes, as well as higher scores in most sensory traits than the lighter ones.

The quality comparison of eggs laid by laying hens kept in battery cages and in a deep litter system

V. Pištěková, M. Hovorka, V. Večerek, E. Straková, P. Suchý

Czech J. Anim. Sci., 2006, 51(7):318-325 | DOI: 10.17221/3945-CJAS

At present the laying hen rearing is transformed into alternative housing systems which include a deep litter system. As for the poultry nutrition, the replacement of animal protein with vegetable protein in poultry feed is applied. Therefore, in an experiment we evaluated the quality of eggs from laying hens in the cage system as compared to the deep litter system with vegetable protein substituted for animal protein in their feed. 72 ISA Brown laying hens were placed into the experiment. 36 laying hens were kept in the deep litter system and 36 laying hens were kept in conventional cages for laying hens. For the period of 9 months, 36 eggs from the group in the deep litter system were examined, always at intervals of five weeks (i.e. 8 × 36 eggs) and so were 36 eggs from the group in the cage system (i.e. 8 × 36 eggs). We found out that in the deep litter system the mean egg weight was higher (P < 0.01), shell weight was lower (P < 0.01), egg albumen was higher (P < 0.01), yolk weight did not differ (P > 0.05), yolk cholesterol was higher (P < 0.01), yolk colour was darker (P < 0.05), shell strength did not differ (P > 0.05), all in comparison with the cage system of laying hen keeping. The results of the experiment show that where vegetable protein was substituted for animal protein in the nutrition of laying hens, there were differences in the quality of eggs from laying hens kept in the deep litter system and eggs from laying hens kept in the cage system.

The estimation of live weight from body measurements in Yankasa sheep

R.A. Afolayan, I.A. Adeyinka, C.A.M. Lakpini

Czech J. Anim. Sci., 2006, 51(8):343-348 | DOI: 10.17221/3948-CJAS

Live body measurements of weight, height, length, girth, stifle- and hip-width and a measure of muscularity (ratio of stifle to hip width) were monitored on 258 Yankasa sheep stratified into age categories of 1 to over 3 years determined mostly from records and partly by dentition. These animals are from purebred Yankasa sheep kept as a part of the open nucleus-breeding scheme of the National Animal Production Research Institute, Shika, Zaria, Nigeria. The effect of sex, type of birth and age group of lambs on live measurements and muscularity were analyzed by least-squares procedures. All variables examined, except sex, had significant (P < 0.001) effects on all body measurements. At birth, male and single-born lambs were significantly heavier than female and twin-born lambs. At early age, most factors significantly (P < 0.01) influenced the body weight, body dimensions and muscularity traits with single-born lambs being 31% heavier, 10% taller and 11% bigger in girth; more highly muscled than the twin-born lambs. This advantage of male over female born lambs (except in hip-width and girth) for growth and developmental traits was maintained reasonably well to the advanced ages. All phenotypic correlations between body measurements were positive and significant (P < 0.001). The highest correlation coefficient was found between chest girth and body weight. The polynomial equation using chest girth as an independent variable predicted body weight more accurately as compared to the linear equation.

The effect of dietary Jerusalem artichoke (Helianthus tuberosus L.) on performance, egg quality characteristics and egg cholesterol content in laying hens

G. Yildiz, P. Sacakli, T. Gungor

Czech J. Anim. Sci., 2006, 51(8):349-354 | DOI: 10.17221/3950-CJAS

This research was carried out to determine the effect of Jerusalem artichoke (JA) with or without 5, 10% vetch (V) supplementation on performance, egg quality characteristics and egg cholesterol content. In the study, seventy-five 25 weeks-old commercial white laying hens were randomly divided into one control and 4 treatment groups each containing 15 hens. Control group was fed basal diet without JA or V. Treatment group 1, 2, 3 and 4 were fed diets containing 5% V, 5% JA, 5% JA + 5% V and 10% JA + 10% V, respectively. The feeding period lasted 16 weeks. In the study, it was determined that dried-ground JA contained dry matter, crude protein, ether extract, crude fibre, crude ash, inulin and metabolizable energy (ME) at the level of 93.30, 10.02, 0.36, 5.64, 9.05, 15.80% and 3 060 kcal/kg, respectively. At the end of the study, live weight was lower by 4.36-10.09% in the treatment group 10% JA + 10% V compared with the other groups, but feed efficiency was improved in this group. There were statistically significant differences between the groups in egg quality characteristics (P < 0.05, P < 0.001). Egg production was not affected by supplementation of 5, 10% JA with or without 5, 10% V supplementation. Egg yolk cholesterol and total cholesterol content were not different in the groups (P > 0.05). As a result, the addition of JA with or without V has no adverse effect on performance and egg quality in hens.

Change of amino acid profile in Charolais cows' colostrum and transient milk during the first week post partum

R. Zándoki, J. Csapó, Z. Csapó-Kiss, I. Tábori, Z. Domokos, E. Szűcs, J. Tőzsér

Czech J. Anim. Sci., 2006, 51(9):375-382 | DOI: 10.17221/3954-CJAS

In this study the change in amino acid profile in cow's colostrum and transient milk during the first week after parturition was examined in a Hungarian Charolais herd. Experiments were carried out with n = 37 Charolais cows in the same herd in the spring (March-April) of two consecutive years (Experiment 1: 2002, n = 15; and Experiment 2: 2003, n = 22). Colostrum and milk samples were taken by hand milking immediately after delivery, and in 24, 48, 72, and 168 hours post partum. Amino acid contents (%) in samples were measured in milk protein with an automatic amino acid analyser. Data were processed by the software of SPSS.10 statistical program package. In the postpartal period, among essential amino acids significant increases were recorded in methionine, isoleucine, lysine, and phenylalanine, and among non-essential amino acids glutamic acid and proline increased significantly. Simultaneous decreases were recorded in valine, cysteine, aspartic acid, serine, glycine, and arginine. Inconsistent figures were determined for histidine, leucine, tyrosine, and alanine content between Experiment 1 and Experiment 2.

Parthenogenetic development of rabbit oocytes after electrical stimulation

A. Wierzchos

Czech J. Anim. Sci., 2006, 51(9):400-405 | DOI: 10.17221/3957-CJAS

The aim of this study was to determine the effect of electric pulses on the structural and functional condition of rabbit oocytes. The New Zealand White female rabbits at 3-5 months of age and at 3-4 kg body weight served as oocyte donors. Oocytes after flushing from the oviducts were placed between two electrodes in an electroporation chamber which was filled with a dielectric solution. Following a short incubation in B2 medium, oocytes were subjected to an electric pulse released by an electrical pulse generator. Oocytes were then incubated in 500 µl of B2 medium supplemented with 20% foetal calf serum (FCS) at 38°C in an atmosphere of 5% CO2 in air. Oocytes were cultured until the morula/blastocyst stage (approx. 72 h). The experiment was conducted using 430 oocytes obtained post mortem. In vitro cultured oocytes not subjected to an electric pulse were the control. Each group was subdivided into replications according to electric current intensity. The analysis of experimental variants shows that in the first variant all embryos developed to the morula stage but only 10% of them continued to develop to the blastocyst stage. In the second variant we observed that 5-10% of oocytes developed to the blastocyst stage after treatment with 2.0 and 2.5 kV/cm pulse but in the group of 1.0 kV/cm pulse 35% of oocytes developed only to the 2-12 b stage. In the third variant only 1 oocyte (5%) continued to develop to the blastocyst stage, but in the fourth variant oocyte development stopped at the morula stage. In the fifth variant, called an "extreme" one, oocytes stopped to develop at the stage of 2-12 b (about 25%) and the percentage of degenerated oocytes dramatically increased (about 60%).

The effect of selenium source on the performance and meat quality of broiler chickens

S. Ševčíková, M. Skřivan, G. Dlouhá, M. Koucký

Czech J. Anim. Sci., 2006, 51(10):449-457 | DOI: 10.17221/3964-CJAS

The effect of dietary supplementation of selenium in an organic form on performance, carcass traits and selenium content in tissues of broiler cockerels Ross 308 was studied. The soya-wheat-maize diet contained 50 mg vitamin E/kg. The experiment was conducted on 810 straight-run broiler cockerels randomly divided into 3 groups: group I - control, without selenium supplement; experimental group: II - 0.3 mg Se/kg, Se-enriched yeast was applied as a Se source; III - 0.3 mg Se/kg, Se-enriched alga Chlorella as a Se source. The broiler chickens were slaughtered at 42 days of age. In performance traits higher (P ≤ 0.05) live weight of broiler chickens was recorded in the experimental groups (II - 2 430.6 g and III - 2 425.2 g). There were no significant differences between the groups in feed conversion and mortality. Se-enriched alga had the best feed conversion, and selenium supplementation slightly increased mortality in both experimental groups. No significant differences between the groups were found out in carcass traits and dressing percentage. The content of selenium in breast and thigh muscle, feathers and excrements increased (P ≤ 0.05) in both experimental groups compared to the control group. Higher values in breast and thigh muscle and in feathers were measured in the group supplemented with selenium from Se-enriched yeast, also in comparison with the group supplemented with selenium from Se-enriched alga Chlorella. The broiler chickens receiving Chlorella had a higher (P ≤ 0.05) selenium content in excrements compared to the group with Se-enriched yeast. The selenium concentration in liver was higher (P ≤ 0.05) in both experimental groups compared to the control. The supplement of selenium from Se-yeast and Chlorella in the diet for broiler chickens increased the microelement concentration in muscle.

The use of treated rape cake in a calf starter diet

E. Göpfert, M. Trčková, R. Dvořák

Czech J. Anim. Sci., 2006, 51(11):491-501 | DOI: 10.17221/3969-CJAS

The objective of the experiment was to evaluate the effect of starter diet containing 10% of treated rape cake (TRC) with a reduced glucosinolate content on calf growth, development and health. The experiment included 45 calves allocated into 3 groups. After the colostrum period (5 days) the calves were fed 4 l of pooled fresh milk per calf/day and one of the starters ad libitum. The control group (S) was fed Standard starter with components with a standard nutrient content including fibre. Comparative group T was fed Telstar starter, which contained whole maize kernels and protein pellets. Experimental group G was fed Grant starter containing 10% of treated rape cake. The calves were fed hay ad libitum from 10 weeks of age. The average starter consumption (calf/day) over a 90-day feeding period was 1.34, 1.72 and 1.45 kg of the Standard, Telstar and Grant diet, respectively. An insignificantly higher body weight of calves was recorded for the Grant group at the end of the experimental period. When the calculated indices were compared, it was obvious that the weight gains obtained with experimental starters Grant and comparative Telstar were by 4.0% higher and by 5.4% lower, respectively, than in the control group Standard. No significant changes in the parameters of nitrogen, energy, lipid and mineral metabolism, health status, hepatic parenchyma and thyroid function were observed throughout the experimental period. The diet based on experimental starter Grant had no adverse effect on the ruminal fermentation in calves. It may therefore be concluded that the starter diet with 10% content of treated rape cake had no adverse effect on calf growth and performance.

Responses of milk urea nitrogen content to dietary crude protein level and degradability in lactatingHolsteindairy cows

S.W. Zhai, J.X. Liu, Y.M. WU, J.A. YE, Y.N. XU

Czech J. Anim. Sci., 2006, 51(12):518-522 | DOI: 10.17221/3972-CJAS

Two experiments were conducted to investigate the effects of dietary crude protein level and degradability on milk urea nitrogen (MUN) content. In experiment 1, twelve multiparous lactating cows averaging 176 days in milk were divided according to DIM and milk production into three 4 × 4 Latin squares with four 2-week periods. Cows were fed four diets with different crude protein levels (13.0, 14.0, 15.0, and 16.0%, DM basis) with isocaloric, respectively. Crude protein levels had a low effect on milk yield and composition (P > 0.05), but a significant effect on MUN content. There were significant differences in the MUN content of cows fed either of the two diets (P < 0.01). In experiment 2, fifteen multiparous Holstein dairy cows averaging 91 days in milk were classified according to DIM and milk production into five 3 × 3 Latin squares with three 3-week periods. Cows were fed one of the three isocaloric and isonitrogenous diets with RUP being 30.8%, 36.2%, and 41.6% (CP basis), respectively. Milk yield, milk composition, and MUN content were not significantly affected by protein degradability, and there were no significant differences between any two dietary treatments (P > 0.05). These results indicated that MUN might be used as a parameter to monitor the change in dietary protein levels.

Prospects of classical cross protection technique against Citrus tristeza closterovirus in Pakistan: A review

M. Abbas, M. M. Khan, S. M. Mughal, I. A. Khan

Hort. Sci. (Prague), 2005, 32(2):74-83 | DOI: 10.17221/3769-HORTSCI

In Pakistan citrus groves in general are facing a serious problem of decline that is attributed to different causes. The major cause, however, is the prevalence of citrus virus and virus-like diseases; Citrus tristeza virus (CTV) is of utmost concern. Although CTV has been identified and characterized on the basis of serological and physical properties, no information is available on the strains of CTV in Pakistan. The identification of CTV strains will be helpful in developing strategies to control the decline of citrus trees to a great extent. Many citrus growing countries have successfully used the technique of cross protection to minimize the drastic effect of severe CTV strains. By pre-immunization of the citrus tree with mild strains, the decline can be controlled to increase the life span of the citrus tree. In this study we focus on the possibility of establishing a cross protection technique in Pakistan against the CTV strains.

Ethylene production in apple infected by Gleosporium album Ostrw. at cold storage

J. Goliáš, A. Němcová, P. Mýlová

Hort. Sci. (Prague), 2006, 33(1):1-6 | DOI: 10.17221/3732-HORTSCI

In ten cultivars of apple fruit, ethylene production expressed in μl/kg/h was determined. The cultivar Resista exhibited a higher ethylene production and can be differentiated from other cultivars. The production ranged from 4.2 ± 0.58 μl/kg/h in the case of Meteor cv. up to 131.6 ± 5.5 μl/kg/h in Resista cv. Infected fruit of Topaz cv. had a lower ethylene production at cold storage temperature (3°C) than some healthy fruit. All examined cultivars can be divided into three clusters. Discriminant analysis and canonical correlation analysis of the examined apple fruit led to the determination of healthy and infected fruit. Values of ethylene production were analyzed on intact fruit by using headspace gas analysis by CGC with thermal desorption technique. Carbosieve G was chosen as the adsorbent material for the traps due to its relatively high affinity for light hydrocarbons such as ethylene. For a full trap of ethylene in the enrichment column the sufficient amount of percolating gas is about 0.3 l.

The economics of modern plum orchards in the Czech Republic

R. Vávra, J. Blažek, J. Mazánek, L. Bartoníček

Hort. Sci. (Prague), 2006, 33(2):47-56 | DOI: 10.17221/3739-HORTSCI

This paper deals with an evaluation of the economics in two commercial plum orchards which were established between 1993-1997 using dense tree-spacing and modern principles of orchard management. This evaluation was conducted in 1994-2004 with the following cultivars: Bluefre, Common Prune, Čačanska lepotica, Čačanska najbolja, Gabrovska, Hamanova, Opal, President, Ruth Gerstetter,Stanley, and Valjevka. Orchard establishment costs, pruning costs, annual orchard operating and pest management costs and returns up to 11 years of growth are given. A denser planting had a positive influence on total yields per hectare with higher returns. Costs per ton of fruit mostly varied between 4 and 7 thousand CZK, whereas farmer prices fluctuated between 7.6 to 13.6 thousand CZK per ton. The highest returns after seven years of growth from one hectare were exhibited by the cultivar President on rootstock St. Julien A in the spacing 4 × 2.5 m followed by the cultivar Stanley on rootstock Myrobalan and the same spacing.

Studies on salt stress tolerance of citrus rootstock genotypes with arbuscular mycorrhizal fungi

A. A. Murkute, S. Sharma, S. K. Singh

Hort. Sci. (Prague), 2006, 33(2):70-76 | DOI: 10.17221/3742-HORTSCI

Citrus is grouped under the salt sensitive crops. Mycorrhizal fungi, a symbiotic relationship between plant roots and beneficial fungi, are supposed to impart the stress tolerance in the host plants. The stress tolerance improved due to Arbuscular Mycorrhizal fungi (AM fungi) colonization can be attributed to enhanced mineral nutrition. In the present study the efforts are made to evaluate the effectiveness of AM fungi with two citrus genotypes under salt stress. Three-month-old seedlings of Karna Khatta (Citrus Karna) and Troyer Citrange (Poncirus trifoliata × Citrus sinensis) were inoculated with the indigenous soil based AM inocula (mixed strains). The salinity gradient was developed by frequent irrigation with NaCl (0, 50, 100, 150 mM w/v). The results indicated that all the physical parameters were affected with increasing salinity. The proline accumulation increased while the chlorophyll, calcium and magnesium contents decreased significantly with increasing salinity. In general, the decreased AM colonization did not show any significant effects under salt stress.

The effect of Lignofert organic fertilizer on formation and quality of head lettuce yield

M. Valšíková, A. Viteková

Hort. Sci. (Prague), 2006, 33(3):114-118 | DOI: 10.17221/3748-HORTSCI

Nowadays soils for vegetable growing are poor in humus because the possibility of using stable dung is limited. The application of Lignofert organic carbonaceous fertilizer made of ground lignite seems to be a solution. It is intended as a fertilizer for the field or greenhouse growing of vegetables, as a component to composts, soil substrates and likewise. Lignofert effects on the formation of lettuce yield, weight of heads and NaNO3 content were studied in 2003 to 2005. Head lettuce grown in a greenhouse and in field conditions was a biological material. Average lettuce yields and average weight of heads in 2005 were statistically highly significantly higher in variants with Lignofert in comparison with the control variant grown in the greenhouse and in the field. The Lignofert effect on nitrate content in lettuce heads was not proved statistically.

Seven-year orchard performance of eleven new apple cultivars from Holovousy in comparison with some commonly grown ones

J. Blažek, J. Křelinová

Hort. Sci. (Prague), 2006, 33(4):131-139 | DOI: 10.17221/3752-HORTSCI

In an orchard trial that was established in the spring of 1999 on M 9 rootstock at the spacing of 4 × 1 m, eleven new apple cultivars bred in Holovousy (Angold, Julia, Nabella, Primadela, Produkta, Resista, Rubinstep, Rucla, Selena, Vysočina and Zuzana) were evaluated in comparison with three standard varieties (Gala, Golden Delicious and Jonagold) and another two with resistance to scab (Rosana and Topaz). In the first three years, the incidence of scab and mildew was evaluated under limited chemical protection. In 2000-2005 on each of 10 randomly selected trees of each cultivar, the time of flowering and optimum harvest ripening were recorded, flower set and fruit sets were rated, yield per tree and weight of 10 fruit samples were measured. Trunk diameter was measured between 2002 and 2005. The early summer apple Julia had the healthiest state and it was recommended for organic growing. Selena was the most precocious, the least vigorous and had the highest crop efficiency. The highest annual yields per tree were recorded with Produkta, but this cultivar had the highest proportion of trees with biennial bearing. Primadela achieved the highest cumulative yields, whereas Angold brought the largest fruits on average. With the obtained results, the evaluated cultivars were characterised by some important features or recommendations for growers.

Study of some characteristics of vegetable pepper varieties

M. Valšíková, J. Králová, Š. Barkoci

Hort. Sci. (Prague), 2006, 33(4):153-157 | DOI: 10.17221/3755-HORTSCI

In three test years an assortment of 15 varieties of vegetable pepper (Capsicum annuum L.) were grown in field conditions to study experimentally some of their morphological and biological properties. Mean plant height ranged from 435.7 mm (cv. Lastočka) to 636.7 mm (cv. Srbská). The smallest fruits had cultivars Čerešňová and Kecskeszarv with the weight of 4.86 g and 17.68 g. Average weight was the highest at varieties Pola kapia (92.23 g) and Melišor (91.92 g). The biggest length of mature leaves over 100 mm was measured at varieties Dolmy, Podarok Moldavy and Tuba; the smallest leaves according to length and width had variety Čerešňová. The mean vitamin C content in fruits about 2,000 mg/kg at green mature stage was found in cv. Bohatýr, Čerešňová and Podarok Moldavy. The highest vitamin C content in red fruits was analyzed at cv. Čerešňová (2,551.0 mg/kg) and Lastočka (2,422.2 mg/kg). Other observed characteristics were colour, shape and taste of fruits, colour of leaves and fruit wall thickness.

Evaluation of BC Williams and PI1/6 pear cultivars for their compatibility with 49 quince genotypes and their susceptibility to fire blight: Short communicaton

T. Thomidis, C. Tsipouridis

Hort. Sci. (Prague), 2006, 33(4):163-166 | DOI: 10.17221/3757-HORTSCI

In this study, the compatibility of the pear cultivars PI1/6 and BC Williams with 49 quince genotypes was evaluated. The results showed that the cv. PI1/6 had a good compatibility with several of the quince genotypes, and the cv. BC Williams only with a few of them. Differences were also found in their susceptibility to fire blight (Erwinia amylovora). The cultivar PI1/6 was very susceptible, while the cultivar BC Williams was relatively tolerant.

Elementary financial analysis of the Forests of the Czech Republic, state enterprise

V. Kupčák

J. For. Sci., 2005, 51(3):127-140 | DOI: 10.17221/4551-JFS

The basic feature of an economic reform of the forestry in the Czech Republic after 1990 was separation of supervision in the state forests from operating performance. The Forests of the Czech Republic, state enterprise, was charged with management and supervision, hence economic activities of the subject are provided on the basis of contracts by entrepreneurial units called contractors in the forestry. The purpose of the paper is economic analysis of the Forests of the Czech Republic, state enterprise, in the period 1998-2002. The objective is the construction and testing of an elementary method of financial analysis as well as outline of financial situation and development of the chosen subject generally. The paper contributes to branch economy analysis, common in agriculture and wood-processing industry.

Species diversity, abundance and dominance of macromycetes in beech forest stands

I. Mihál, K. Bučinová

J. For. Sci., 2005, 51(5):187-194 | DOI: 10.17221/4558-JFS

The aim of this paper is to contribute to the knowledge of dynamics of species diversity, abundance, distribution of fruiting bodies and dominance of macromycetes in mycocoenosis of beech monocultures. The problems were studied in beech monocultures on three permanent research plots with various impacts of air pollutants generated by the aluminium plant in Žiar nad Hronom. Over the research period we determined 121 macromycete species and one species of imperfect fungus. We found relatively balanced values of abundance, fruiting body distribution and species dominance on all the examined plots. The species diversity in groups consisting of the most dominant species was practically the same on each plot. As for the ecotrophic requirements of individual macromycetes, we can conclude that the diversity of tree parasites decreased with decreasing pollutant load. We also found out relatively balanced numbers of lignicolous saprophytes and terrestrial saprophytes on each research plot. Air pollutants also influenced the species spectrum of ectomycorrhizal macromycetes negatively (only 6 species on the plot with highest pollution stress and 21 species on the plot with lowest pollution stress).

Dynamics of oak mycorrhizas

V. Pešková

J. For. Sci., 2005, 51(6):259-267 | DOI: 10.17221/4562-JFS

A decline of macromycetes, especially of ectomycorrhizal species, has been described in the last decade in various parts of Europe. These changes are attributed to direct or indirect effects of air pollution. In Central Europe these changes correlate with visual damage of forest. Many ectomycorrhizal fungi seem to be very suitable bioindicators of the disturbance of forest ectotrophic stability. Stages of this disturbance can be linked directly to particular phases of impoverishment of ectomycorrhizal mycocoenoses. These conclusions have been obtained from long-term research on permanent plots (1,000-2,500 m2) in spruce and oak forests in the Czech Republic, but it seems that they are valid generally. For the quantification and study of mycorrhizal activity a special method has been developed and applied. The analyses of mycorrhizas from the same plots in the period 2000-2002 indicate large mycorrhizal dynamics. These data correlate with data obtained from a fruiting bodies survey. Both the percentage of ectomycorrhizal species and the ratio of active mycorrhizas are highly sensitive to outer impacts (air pollution, acidification, fertilization). Their decrease is in correlation with the strong defoliation of trees and can be used for the prediction of further development in comparable stands.

A role of the mechanical preparation of soil in the natural regeneration of pedunculate oak (Quercus robur L.) in floodplain forests

K. Houšková

J. For. Sci., 2005, 51(8):371-379 | DOI: 10.17221/4572-JFS

The subject of our research was to verify effects of the mechanical preparation of soil in the natural regeneration of pedunculate oak in a floodplain forest. On the site of a hard-wooded floodplain forest at the confluence of the Morava and Dyje rivers (Czech Republic), several sample plots were established differing in the preparation of soil during regeneration, in weeding the plots and in the period of the implementation of soil surface scarification before and after the fall (or distribution) of acorns. On the basis of results obtained, mechanical preparation of soil on non-weed-infested plots in the heavy seed year is not necessary, however, it supports seedling emergence from acorns and eliminates weed tree emergence and weed. However, it is better to realize it only after the fall of acorns and to incorporate them into soil and thus their emergence will be increased. Soil scarification can be carried out also in the course of harvesting the parent stand through the extraction of wood and slash from the regenerating area. In weed-infested stands, however, the thorough preparation of soil before the fall of acorns appears to be a necessity.

Notes on invasive and expansive trees and shrubsOriginal Paper

J. Möllerová

J. For. Sci., 2005, 51(20):19-23 | DOI: 10.17221/11844-JFS

Expansion and invasion of plants indicate successful colonization and competitive abilities of species. There are fewer invasive and expansive woody plants than herbs. Main expansive (native species) trees and shrubs are Acer platanoides, Acer pseudoplatanus, Clematis vitalba, Crataegus sp. div., Fraxinus excelsior, Prunus spinosa, Rubus sp. div., Sambucus nigra. Main invasive (alien species) are Acer negundo, Ailanthus altissima, Amorpha fruticosa, Cytisus scoparius, Fraxinus pennsylvanica, Lycium barbarum, Mahonia aquifolium, Physocarpus opulifolius, Pinus strobus, Populus × canadensis, Prunus serotina, Quercus rubra, Rhus typhina, Robinia pseudoacacia, Symphoricarpos albus, Syringa vulgaris. Dominant characteristics of expansive and invasive species are dispersibility of seeds and capacity of vegetative propagation.

Application of Mg-fertilizers to prevent and to decrease Norway spruce yellowingOriginal Paper

V. V. Podrázský, S. Vacek, J. Remeš, I. Ulbrichová

J. For. Sci., 2005, 51(20):43-48 | DOI: 10.17221/11848-JFS

Yellowing of the Norway spruce is a relatively common problem in many areas of the Czech Republic. In some of them, it is also connected with forest decline; it was studied in the Šumava (Bohemian Forest) Mts. and in the western part of the Krušné hory Mts. This unfavourable phenomenon is initiated by several ecological as well as anthropic processes, one of the most important being the imbalance of forest stand nutrition. Particular reasons lead to the deficiency of nutrients, especially of magnesium. Solution of this undesirable trend is the profound ecological analysis and cause-oriented treatments. Besides lowering the air pollutant input, fertilization with deficient nutrients is a successful treatment in the forest stand management in affected areas. In the areas of interest, the application of a relatively small amount of appropriate fertilizer (SILVAMIX Mg) led to considerable improvement in the defoliation dynamics and yellowing progress since the first years after use.

The occurrence of fungal and insect pests in riparian stands of the central Hron and Slatina rivers

J. Kodrík, M. Kodrík, P. Hlaváč

J. For. Sci., 2006, 52(1):22-29 | DOI: 10.17221/4483-JFS

The paper deals with the occurrence of fungi and rusts, viruses and insects on main woody species in riparian stands along the middle courses of the Slatina and Hron rivers in Slovakiain 2002-2004. Forty fungal species, rusts and viruses and 79 insect species were found. The highest number of fungi occurred on the branches and twigs of poplar where Cryptodiaporthe populea (Sacc.) Butin and Phellinus igniarius (L.) Quél. had the highest representation and so the influence on the health condition. Melampsora alliipopulina Kleb., Poplar mosaic carlavirus, Venturia po-pulina (Vuill.) Fabr. and Venturia tremulae Aderh dominated on the leaves. The most frequently present fungus on the aspen was Armillaria sp., Phellinus igniarius (L.) Quél., on the alder a new hybrid from the genus Phytophthora - alder Phytophthora, Valsa oxystoma Rehm., Inonotus radiatus (Sowerby) P. Karst. and Inonotus obliquus (Fr.) Pilát. From the insect species Melasoma vigintipunctata Scop. and Phyllodecta vitellinae L. caused total defoliation on willows. The highest occurrence on the black poplar was on the leaf stalks represented by Pemphigus spirothecae Pass. species, on the alder it was Cryptorrhinchidius lapathi L. on the twigs and Agelastica alni L. on the leaves.

The host spectrum of Dothistroma needle blight Mycosphaerella pini E. Rostrup - new hosts of Dothistroma needle blight observed in theCzech Republic

M. Bednářová, D. Palovčíková, L. Jankovský

J. For. Sci., 2006, 52(1):30-36 | DOI: 10.17221/4484-JFS

Dothistroma needle blight Mycosphaerella pini E. Rostrup and its anamorphic stage Dothistroma septospora (Dorog.) Morelet was detected for the first time in the territory of the Czech Republic in a consignment of imported plants of Austrian pine Pinus nigra Arnold in 1999. In 2000, it was also found on Pinus nigra in an open planting in a plantation of Christmas trees by the village of Jedovnice near Brno in South Moravia. In the Czech Republic, Dothi-stroma needle blight was identified on 13 species of pine. Pinus nigra Arnold and Pinus mugo Turra are the most frequent hosts. In addition to these species, Dothistroma needle blight was observed on Pinus ponderosa Douglas ex Lawson, Pinus jeffreyi Grev. et Balf, Pinus banksiana Lamb., Pinus contorta Douglas, Pinus rotundata Link, Pinus leucodermis Ant. and Pinus sylvestris L. Finds on Pinus aristata Engelm., Pinus rigida Mill., Pinus heldreichii H. Christ. and Pinus cembra L. var. sibirica (Du Tour) G. Don. are a certain rarity. These species are not mentioned anywhere as potential hosts of Dothistroma needle blight. As for the species of other genera Picea pungens Engelm., Picea abies L. Karst. and last but not least Picea schrenkiana Fisch. & C. A. Mey were also observed as hosts. The host range of Dothistroma needle blight recorded in papers is noted as well.

Spontaneous infiltration of broadleaved species into a spruce monoculture left without tending

P. Jelínek, P. Kantor

J. For. Sci., 2006, 52(1):37-43 | DOI: 10.17221/4485-JFS

An experimental stand was established as a monoculture by planting Norway spruce on a clear-felled area in 1925. In 1958, a research thinning experiment was established there. Control plots and the study of their development without anthropic interventions are of interest in particular. The spruce monoculture nearly disintegrated and the stand-forming role was taken over by species which occurred there originally as admixed ones. The stand became sparser and it was associated with the spontaneous regeneration of broadleaves. Out of the eight control plots three plots were selected differing significantly in stocking and extent of natural regeneration. The development of regeneration was studied in detail on these plots. The undergrowth consisted of 24 woody species in a total number of 6,000 individuals per hectare and about two thirds of them belonged to trees. The results of the study show a possibility to convert a spruce monoculture to a broadleaved commercial forest using the spontaneous regeneration of trees.

Final documents of forest management regulation in the Slovak Republic and their possible interdepartmental use for environmental impact assessment

F. Kundrík

J. For. Sci., 2006, 52(1):44-50 | DOI: 10.17221/4486-JFS

Dokumenty týkajúce sa regulácie hospodárenia v lesoch sa prakticky až dodnes považovali za materiály, týkajúce sa skoro výlučne len jednotlivých odborných rezortov. Na základe Vyhlášky Ministerstva financií SR č. 465/1991 ich možno efektívne využívať aj v rámci rezortov financií a spravodlivosti. Ďalšie významné medzirezortné využitie týchto dokumentov vyplýva zo Zákona č. 127/1994 o posudzovaní environmentálneho dopadu. Cieľom práce je demonštrovať proces posudzovania na konkrétnom príklade - ploche patriacej do lesného pozemkového fondu. Okrem máp, výsledkov pozorovania, slovných popisov a súborov numerických údajov, týkajúcich sa jednotlivých porastov, obsahujú tieto dokumenty aj kódované údaje, ktoré pre väčšinu užívateľov nie sú zrozumiteľné bez využitia dekódovacích kľúčov. A práve tieto posledné údaje majú pri vyhodnocovaní environmentálneho dopadu najvyššiu výpovednú hodnotu. Po nadobudnutí platnosti pripravovaného zákona (vyhlášky) o strate vlastníctva, vyplývajúcej z prohibitívnych a ďalších podmienok v lesnom hospodárstve v súvislosti s presadzovaním verejno-prospešného záujmu (Kundrík et al. 1999), významne vzrastie dôležitosť využitia finálnych dokumentov týkajúcich sa regulácie hospodárenia v lesoch SR.

Regime and dynamics of soil moisture in forest ecosystems of Záhorská lowland

L. Tužinský

J. For. Sci., 2006, 52(3):108-117 | DOI: 10.17221/4492-JFS

The paper describes the regime and dynamics of the soil moisture content of sandy soils in Záhorská lowland during different growing seasons. Research plots are situated near Kamenný mlyn, approximately 3 km from Plavecký Štvrtok and 8 km southward from the town of Malacky. Changes in the soil moisture content are described by soil moisture constants (MCC, PDA, WP) and its relation to atmospheric precipitation and to the character of undergrowth is shown. The low water-holding capacity of sandy soils and their high drainage together with dense root system do not allow the sufficient saturation of soil during the growing season. The low wilting point value (2%) leads to the consumption of all available water in the soil. The most frequent is the semiarid interval of soil moisture (PDA -WP) with reduced availability of water to plants (> pF 3.1). The arid interval (< WP) occurrence on hot summer days results in a decrease in transpiration and assimilation intensity of plants, their physiological weakening and premature fall of assimilation organs.

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