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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.

The disease caused by Tomato spotted wilt virus (TSWV) belongs to the most destructive diseases of tomato all over the world. Therefore, tomato has been subjected to many breeding efforts, including the incorporation of resistance to the virus. Recently emerged approaches, ideas and technologies could affect the future direction of the virus resistance breeding. In particular molecular techniques have provided opportunities in the form of linked molecular markers to speed up and simplify the selection of host resistance genes. Transformation of an inbred tomato line with the TSWV nucleoprotein gene cassette resulted in high levels of resistance to TSWV that have been retained in the hybrids derived from the parental tomato line. These and other techniques offer great opportunities for improving the virus resistance and, therefore, it is time to reconsider the future direction of resistance breeding in tomato. The effort has been made to review available sources of resistance, conventional breeding methods, marker-assisted selection, pathogen-derived resistance and transgenic resistance approaches in this paper.

The objective of the study was to verify the hypothesis that GEN (genistein - phytoestrogen and an inhibitor of tyrosine protein kinase - TPK) effects on pig oocyte maturation and cumular cell expansion under in vitro conditions are connected with its estrogenic activity. Oocytes were cultivated for 24 hours up to the stage of the first meiotic metaphase (MI). Three different doses of GEN (13, 40, 80 µg/ml of medium) and also three doses of GIN, genistin, an analogue of GEN without effects on TPK, (80, 160 and 240 µg/ml of medium) were tested. To verify the reversibility of GEN effects, the oocytes were first cultivated for 24 hours with 80 µg of GEN per 1 ml of medium and then for another 24 hours without any GEN. GEN blocked pig oocyte maturation at the stage of the germinal vesicle (GV), depending on the dose. After rinsing out the GEN the oocyte maturation recovered, but with abnormalities (32%). GIN in a concentration of 80 µg/ml of medium induced a significant blockage at the GV stage (18%). With an increase in the GIN concentration, the number of oocytes blocked at the GV stage significantly decreased, but the abnormal maturation increased (up to 31%). GEN inhibited the cumular cell expansion in proportion to its dose. GIN had a less pronounced effect. As GEN and GIN effects demonstrate similar patterns, it is probable that estrogenic activity is involved.

The aim of the study was to evaluate the growth rate and selected carcass and meat quality parameters in bulls fed a high-grain diet and to compare the results with those obtained in bulls fed a diet based on preserved roughage. The trial included 18 Czech-Pied bulls fed a diet with a high proportion of concentrated feed and 18 Czech-Pied bulls fed a diet based on maize silage, used as a control group. The trial was launched after the weaning of calves. During the fattening period, live weight and average daily weight gain were monitored. The bulls were slaughtered at the live weight of 550-600 kg, the mean age at slaughter was 473 days for the high-grain diet group and 474 days for the control group. The carcasses were classified to SEUROP quality grades, and carcass gain and dressing percentage were calculated. Samples of m. longissimus pars thoracis were taken from five bulls in each group to examine selected meat quality parameters. In the period from weaning to slaughter the high-grain diet bulls and the control bulls achieved the average daily weight gain of 1.29 kg and 1.21 kg, respectively. Differences between the groups were not significant. The high-grain diet group showed higher average carcass weight and higher carcass weight gain, differences between the groups were not significant, either. As to meat quality parameters under study, a significant difference was found only in meat lightness (L*), with the mean value in the high-grain diet group being significantly (P ≤ 0.01) lower than in the control group. The other meat quality parameters did not show any significant differences between the groups. In this study, the high-grain diet gave similar performance as the maize silage-based diet in fattening bulls. The high-grain diet group and control group showed comparable average daily weight gain and selected carcass and meat quality parameters.

The frequent presence of rye translocation 1B/1R in common wheat is well known as well as its unfavourable effect on bread-making quality. These translocated materials make up more than one tenth of all wheat varieties registered in the Czech Republic and due to their lower technological value they are predominately used for livestock feeding in spite of the lack of information about their desirability for monogastric animals. Our study was aimed at a general effect of 1B/1R translocation, including other grain characteristics in model feeding tests with laboratory rats. Triennial evaluation of selected chemical and technological characteristics of winter wheat grain, including feeding characteristics in the model set of 18 DH lines with/without 1B/1R translocation, confirmed a highly significant effect of year on evaluated parameters. Wheat lines with the presence of 1B/1R translocation showed a significantly higher value of relative viscosity, crude protein content and higher proportion of the albumin + globulin fraction. This was manifested negatively in the technological characteristics of the gluten index (GI) and the Zeleny sedimentation test of these wheat lines. Detected values of relative viscosity, grain hardness (PSI) and albumin-globulin fraction were significantly influenced by the genotype of the wheat line. The relationships of evaluated grain characteristics to the results of feeding test were not unequivocal. The presence of 1B/1R translocation significantly decreased the values of balance in these characters: net protein utilization (NPU) and biological value of proteins (BV), however the effect of the 1B/1R translocation on protein efficiency ratio (PER) was not confirmed. Correlation analyses showed low mutual relationships among the parameters of balance and growth tests. A lower but significant positive correlation of the albumin + globulin fraction and a negative correlation of storage proteins with growth parameter PER were also observed. It is possible to summarize that individual relation between albumins + globulins and gluten protein composition of grains influenced the values of PER more significantly than the presence of 1B/1R translocation.

Citrus Greening Disease (CGD) was critically reviewed with respect to its history, origin, symptomatology, host range, pathogenic association, identification and detection, transmission and management. It is evident that the citrus disease has emerged as a potential serious threat to citrus production in all the citrus growing countries of the world including Pakistan. It is has been proved that in Pakistan the greening disease is the major cause of citrus decline; hence it is necessary to formulate definite planning and strategies.

The Pinus mugo complex (P. mugo Turra sensu lato, and/or species aggregate or group - P. mugo agg., including its internal as well as external aggregate hybrids) is an important fragment of European dendroflora. For its high variability this complicated group has not been solved in taxonomical terms satisfactorily yet. Most problems are mainly caused by a large amount of taxa of uncertain value described in the past, which often more or less overlap or are based on insufficiently researched and unsuitably interpreted characters. Such facts coincidently cause further problems in applied disciplines. Specialized European literature already contains a large amount of information referring to individual taxa of this complex. Much information is listed under various, often commonly not known or not used scientific names. In order to make the information available and useful, it was necessary to collect the most frequent names used in the past and to assort them in a tabular manner into a convenient synoptic schedule respecting the present concepts of the complex and assign them with the present most commonly used names.

The present distribution of forests and the degree of their transformation by man are the results of natural factors and cultural development. The limit between forested areas and open spaces, as well as differences between intensively used forests and those showing small or no traces of human intervention, is determined by social needs and values, economic opportunities, and political regulations. Forests are currently perceived by the population as physical and social spaces profoundly influenced by timber use and forest management. Their social and political significance is in full evolution. The multiple demands on forests in a rapidly evolving economic, social, and political environment require maintaining a high level of forest management standards and a flexible adaptation of multiple-use forestry to the complex interactions between the private and public sectors.

The purpose of the study was to assess, in respect of selected physical properties, the reclamation of the northern slope of the outside spoil bank of the Belchatów brown coal mine by reforestation carried out 20 years ago. Investigations were carried out on 55 permanent research plots. This study confirmed the efficiency of reclamation of strip-mine spoils, and its results allowed to point out the properties of initial soils as the most useful characteristics for the assessment of land reclamation by reforestation.

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.

The paper presents results from a study of sycamore maple development, health condition and growth in forest altitudinal vegetation zones (FAVZ) 6 and 7 occurring in pollution damage zones A and B in the air-polluted region of Krušné hory Mts. as compared with the trees of identical height in FAVZ 4 and 5 occurring in pollution damage zone D in the Bohemian-Moravian Upland. Sycamore maple develops a fully diversified root system. On spread mounds it creates only a superficial root system and its growth is retarded. The growth of sycamore maple is limited by the layer of humus horizons. If the layer thickness is over 20 cm, the sycamore roots would grow into mineral horizons.

This article describes the problem of forest reclamation of settling basins after industrial processing of manganese ore and pyritic shale at the age of 20-30 years. Soil properties of anthropogenic soil (overlaid layers, deposited sediments), nutrition state of assimilation organs, vitality of aboveground organs of tree species were investigated by instant visual evaluation using recommended macromorphological criteria and architecture of the Scots pine (Pinus sylvestris L.) root system.

Important parts of the forest sector are forest engineering constructions and capital construction of forest road network which improve the optimal management of forests and forest stands and their reasonable opening by a forest road network. The basic frameworks of forest road network are forest transport roads of various grades and categories. The paper discusses the basic parameters of forest transport roads such as the length of forest transport roads and their density outspread to the area of a particular district above all. The conditions of forest opening in 41 Natural Forest Regions of the Czech Republic and in the Czech Republic as a whole are shown and confronted on the basis of these parameters. A dilemma of the double division of forest transport roads according to the standard ČSN 73 6108 - Lesní dopravní síť (Forest Transportation Network) and according to the methodology used by Forest Management Institute in Brandýs nad Labem is also described in the paper. Although it is not suitable to use two methods of evaluation, there is no tendency to unify it.

The present paper is the first contribution from the biomass quantification series which is realized by Forestry and Game Management Research Institute in the Krušné hory Mts. (Northern Bohemia). This study is aimed at blue spruce substitute stands. Research was done within the blue spruce experiment Fláje II in the Krušné hory Mts. (800 m above sea level in the spruce forest vegetation zone, acidic category). Results showed that the aboveground biomass of the investigated substitute blue spruce stand without thinning amounted to approximately 56 thousand kg of dry matter per ha at the age of 22 years. Wood and bark of branches are the most important parts of the aboveground biomass (ca 40%). Needles and stem wood accounted for approximately 26 and 28% and stem bark only for 6%. At the age of 22 years, the investigated substitute blue spruce stand accumulated: N - 336 kg, P - 28 kg, K - 138 kg, Ca - 159 kg, Mg - 28 kg per hectare. Thinning with the consequent removal of aboveground biomass (54% of trees, 40% of basal area at the age of 16 years) represented a loss of ca 8.7 thousand kg/ha of total biomass, which contained 53 kg of N, 5 kg of P, 22 kg of K, 26 kg of Ca and 4 kg of Mg. The removal of biomass in areas previously degraded by acid deposition may result in the deficiency of Ca and Mg because of their low content in forest soil. On the other hand, thinning supported the faster growth of trees left after thinning and consequently faster biomass and nutrient accumulation.

The collection and sale of asparagus (Asparagus racemosus Willd.) is a major source of income for Praja and Tamang castes around the Royal Chitwan National Park (RCNP) in Nepal. However, the forests where asparagus is harvested are becoming depleted threatening the livelihood of collectors. To address this issue, at sustainable harvesting practices, the research reported here applied the contingent valuation method (bidding game) and estimated the average willingness to pay (WTP) of collectors to two asparagus collection scenarios. In the first scenario, if forests under the Department of Forests jurisdiction were managed for sustainable harvesting at 1995 rates, the average WTP of collectors was 4.4 NR/kg. In the second scenario, if the forest in the RCNP is managed in such a way that both the current harvesting rate of asparagus is sustained and they are legally allowed to collect asparagus at the present rate, the average WTP of collectors was 8.35 NR/kg. Consequently, there is a good chance of earning revenue for the government and sustaining the livelihood of asparagus dependents by the sustainable management of the Department's and the National Park's forests and giving legal permissions to collect asparagus from the National Park, which would have happened anyway but with financial and legal risks to collectors.

The study analyses the growth of beech seedling fine roots and their development in the first five years. The research plots were established in 1997-2003 in community forests of Starý Plzenec (Western Bohemia, Czech Republic). The data are based on annual reviews of beech samplings extracted from surveyed plots. The whole root volume as well as the fine root volume is significantly (on a 95% significance level) growing during the first years after outplanting and there is not any disruption of growth immediately after outplanting.

This study was designed to evaluate basic tree characteristics of Quercus dalechampii Ten. and Quercus polycarpa Schur and to find out differences between them. Total height, height of crown base and diameter at breast height were measured before tree felling. Cut stems were visually checked for heart rot on their basal parts. Diameters were measured on each stem in 1 meter long sections from the base to the point of life crown setting. Average values for both species were compared by t-test. The total height was proved to be statistically different; the height of crown base and diameter at breast height were quite similar for both species. Q. dalechampii Ten. was proved to be of larger stem diameter from the tree foot to the 3^rd height meter; the diameter of Q. polycarpa Schur was superior from that height upwards. However, the most significant interspecies difference was found in a number of stems affected by wood-rot fungi as Q. polycarpa Schur turned out to be less resistant than Q. dalechampii Ten.

The paper evaluates the development of the tree numbers, secondary stand and species composition on eight partial control plots in Klepačov where the conversion of even aged forest managed under the system involving coupes to selection forest has been implemented within the framework of a long-term project. The plots capture various stages of conversion. Plots A, D, and H still possess structures nearing the forest of age classes. The assessment was made of the measurements taken in 1974, 1994, and 2004. Tree numbers on the partial control plots in the diameter degrees 10-70+ decreased in the first inventory period as compared with both the model situation and the initial situation in 1974 due to increased felling volumes in that period. The felling and the subsequent opening of stands resulted in a rapidly developing regeneration, which manifested itself by the increase in the number of trees in diameter degrees 2 and 6 above the values given by the model curve for these diameter degrees. In the second inventory period, tree numbers in these diameter degrees were lower by 11% as compared with the model situation and slightly lower as compared with the initial situation. Moreover, the results of the survey show that the forest stands under the selection system of management are massively invaded by broadleaved species, namely the beech and that danger exists that broadleaves will dominate in the future. This is generally considered undesirable because the quality of broadleaved stems in the stands under the selection system is low.

In the locality Hnilé Blatá (the High Tatras Mts.), the structure was measured of root branches in the windthrown spruces (Picea abies [L.] Karst.). After cleaning the root plates, the number, diameter, and length of individual root branches were measured. Individual root branches were classified into twelve diameter classes - according to their diameters measured in the middle of the root branch length. We found out a high frequency of the root branches in the first three root-diameter classes; the values of the average frequency of root branches smoothly declined with their diameters increasing. We found out the lowest mean values of the root branch length in the first two root diameter classes. However, the values of total average length of root branches were the highest in the first root diameter class and these values continually decreased with increasing values of the root branch diameter. On the basis of the high values of root frequency and of total root length in the thinnest root-diameter classes, it seems that the spruce trees growing in gley soil form a similar root structure as those growing in podzolic brown soil.

The silver fir was planted under mountain conditions in order to reveal its response to the addition of finely ground rocks (limestone and amphibolite) mixed with soil into the planting holes. The results document that the increments of the plantations fertilised with amphibolite were higher by 25% on average than those of the control plantations while the increments of the plantations treated with dolomitic limestone were lower by 13%. Generally, as concerns both the plantations with the application of ground rocks and the control ones, the development of the fir plantations in 1994-2007 is considered successful. As the damage by climatic stresses has gradually diminished, the number of dead trees has been decreasing and the height increments have been increasing in the last years, therefore a positive development is to be expected also in future.

Transgenic plums, Prunus domestica L. clone C5, were inoculated by bud grafting with Plum pox virus (PPV-Rec, recombinant strain originated from plum), PPV-Rec + Apple chlorotic leafspot virus (ACLSV), PPV-Rec + Prune dwarf virus (PDV), and PPV-Rec + ACLSV + PDV. Non-inoculated transgenic plums served as controls. Plants were grown in an open field for 5 years. They were evaluated by visible symptoms, by DAS-ELISA and RT-PCR. Mild PPV symptoms, diffuse spots or rings appeared two years after inoculation in some leaves of plants artificially inoculated with PPV-Rec, PPV-Rec + ACLSV, PPV-Rec + PDV, and PPV-Rec + ACLSV + PDV. Severe PPV symptoms appeared in leaves of shoots growing from infected buds used for inoculation. During the following three years, further weakening of PPV symptoms was observed in transgenic plants. In 2007, very mild PPV symptoms were found in only a few leaves, and over 60%, resp. 70% of the C5 trees showed no PPV symptoms. The presence of PPV was confirmed by ELISA, ISEM and RT-PCR. No difference in PPV symptoms was observed between PPV-Rec and combinations PPV-Rec + ACLSV, PPV-Rec + PDV, PPV-Rec + ACLSV + PDV. No symptoms of ACLSV appeared in combinations of ACLSV with PPV-Rec and PPV-Rec + PDV during 2004-2007, but the presence of ACLSV in leaves of transgenic plants clone C5 was proved by ELISA and RT-PCR. Neither synergistic nor antagonistic effects of ACLSV on PPV-Rec were observed. No symptoms of PDV appeared in combinations of viruses with PDV during 2004-2007. PDV was not detected by ELISA, and the presence of PDV was uncertain by RT-PCR in most of inoculated trees in 2006 and 2007. The results of RT-PCR will be further confirmed by sequence analysis and discussed. These results suggest a possible antagonistic interaction between PPV-Rec and PDV in plum clone C5.

Leaves from uncultivated and unsprayed hazelnut shrubs, Corylus avellana, were sampled from June to August 2005 to obtain information on the phytoseiid mite taxocenoses, population density and intraleaf distribution. Six phytoseiid mite species were identified, of which three, Kampimodromus aberrans, Euseius finlandicus and Neoseiulella tiliarum, were more abundant. The eudominant, slowly moving K. aberrans was found on all leaf samples. Phytoseiid population density averaged 3.16 mites per hazelnut leaf. While on most leaves only one phytoseiid species was found, on some there was cohabitation of two (rarely three) species. The three frequent species mostly inhabited the sheltered microhabitat at the veins of leaves of C. avellana.

Otiorhynchus sulcatus is considered as an important pest of strawberry fields and on potted ornamental plants. The efficacy to control this pest by new Polish products containing azadirachtin and the entomopathogenic fungus Beauveria brongniartii were tested. The aim of the laboratory investigation was to assess the influence of different forms of azadirachtin (A and B) and the entomopathogen on mortality and physiological development of the insect. Mortality after treatment ranged between 86-93%. There were significant differences in the mean number of surviving stages of the insect between Beauveria and neem treatments, but the final total mortality was not statistically different. Sensitivity of all developmental stages to the fungus was observed. In the neem treatments the physiological development of larvae was completely stopped. The level of control achieved by Beauveria and neem for use in outdoor containers is acceptable for practical application.

The study compares two methods for modeling the potential distribution of pests when applied to the European corn borer (Ostrinia nubilalisHubner). The development of the European corn borer (ECB) is known to be closely correlated with daily air temperature as well as other climate variables. The climatic parameters are, therefore, used to predict the potential geographical distribution using tested tools such as CLIMEX or ECAMON. These models consider the climatic suitability of a given site/region for the pest's development and, thus, the possible establishment of a population at a given location. In this study, meteorological data from 1961 to 2000 and from 45 meteorological stations were used to characterise the current climate conditions in the Czech Republic. Validation was based on available field data of the occurrence of ECB in the same period. The climate parameters were later modified according to the estimates based on the combination of three SRES emission scenarios and three global circulation models. Under all climate change scenarios, we noted a marked shift of the pest's potential niches to higher altitudes, which might lead to an increase in the infestation pressure during the first half of this century. The present area of the univoltine population will increase due to temperature increases even above 800 m a.s.l. In addition there is a risk of the establishment of a bivoltine population in the main agricultural areas and 38% of arable land in the Czech Republic before 2050.

Soil bacteria belonging to the genus Azotobacter, Pantoea and some unidentified soil isolates were tested in vitro for phytohormone production under laboratory and soil conditions. The German wheat variety Munk was inoculated by several soil bacteria with exogenously applied hormones (IAA, 2,4-D) and a flavonoid(naringenin) with a half of the amount of recommended doses of fertilizers under greenhouse conditions. Most of the soil bacteria tested were able to produce indole acetic acid (IAA), and stimulated a lateral root development and colonization by the addition of 2,4-D and IAA. A formation of paranodules on roots as a result of crack entry invasion was observed with 2,4-D as well as with IAA. We were able to reisolate the organism from the paranodules and could establish the same results. Analyses for root exudates and in vitro phytohormone production by various bacterial isolates were also carried out, revealing that 2,4-D can be replaced either by high IAA producing bacteria or by exogenous application of IAA. Bacterial survival in the rhizosphere as well as the root and shoot weight of wheat plants were positively affected also by the addition of IAA, 2,4-D and naringenin.

Ditylenchus dipsaci, the stem nematode, is a migratory endoparasite of over 500 species of angiosperms. The main method of D. dipsaci control is crop rotation, but the presence of morphologically indistinguishable host races with different host preferences makes rotation generally ineffective. Therefore, a sensitive, rapid, reliable, as well as cost effective technique is needed for identification of D. dipsaci in biological samples. This study describes the development of species-specific pairs of PCR oligonucleotides for detection and identification of the D. dipsaci stem nematode in various plant hosts. Designed DIT-2 primer pair specifically amplified a fragment of 325 bp, while DIT-5 primer pair always produced a fragment of 245 bp in all D. dipsaci isolates. Two developed SCAR primer pairs were further tested using template DNA extracted from a collection of twelve healthy plant hosts; no amplification was however observed. The developed PCR protocol has proved to be quite sensitive and able to specifically detect D. dipsaci in artificially infested plant tissues.