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The effects of methanolic extract of Dracaena arborea on mean testicular weight, mean cauda epididymal sperm reserve, and testicular morphology were evaluated. A total of sixty mature male Sprague Dawley rats were divided into three equal groups. The first group (A) received distilled water while the other two groups (B and C) received orally the methanolic leaf extracts of Dracaena arborea in two doses (100 and 500 mg/kg, respectively) daily for 84 days. Following oral administration of the extract, mean testicular weight, mean cauda epididymal sperm reserve, and testicular morphology were determined on days 28, 42, 56, 70, and 84. The extract produced a significant and dose-dependent increase (P < 0.05) in the sperm number. There was also a significant increase (P < 0.05) in the mean testicular weights on days 70 and 84 of the extract administration. The testicular morphology remained unchanged while further testicular histology examination revealed increased spermatogenesis. It was concluded that the methanolic leaf extract of D. arborea has fertility enhancing properties.

Genetic diversity and genetic relationships of Czech apple cultivars were evaluated. Trees of 33 Czech apple cultivars and 97 reference foreign cultivars were analysed using the set of 10 SSR (simple sequence repeat) primer pairs. The total of 89 polymorphic alleles were amplified, while the number of alleles per locus ranged from 4 to 14. The SSR dendrogram, based on the Jaccard's similarity coefficient, divided apple cultivars into three major groups: Cox's Orange Pippin, McIntosh and Golden Delicious ancestries. The clustering highly depended on pedigree and origin of apple cultivars. Spontaneous mutated cultivars were identical with their progenitors. We proved that microsatellite markers were useful for evaluation of genetic resources, collection management and cultivar identification.

Differences between the oak lepidopteran communities were studied in Slovakia in 1993 and 1994. Sampling was undertaken between April and October on 3 oak species. Biological traits of larvae were examined in order to explain differences in seasonal guilds among oaks. Cluster analysis shows similarities between communities in the flush feeder guild where the results were influenced mainly by temporal variability; in the late spring guild mainly by site; factors influencing summer feeder and autumn feeder similarities remain unclear. Detrended Correspondence Analysis (DCA) was used to investigate the main gradients explaining variability in communities. Results indicated that the host specificity along axis 1 (A1) and larval ballooning along axis 2 (A2) were important in the flush feeder guild; larval feeding strategy along A1 and the degree of defoliation by Lymantria dispar along A2 were important in late spring feeders; the year of study along A1 and host specificity along A2 were important in the summer feeder guild; and adaptation to lower quality of food along A1 and host specificity along A2 for the autumn feeder guild. The results are discussed.

Assemblages of earthworms were evaluated in spruce and beech stands in the Kienhaida Nature Reserve (Krušné hory Mts., Czech Republic) and its immediate surroundings, where site conditions were modified by the soil preparation for forest regeneration. The beech stands of the reserve showed low diversity but higher earthworm abundance than did the spruce stands, which in turn showed the lowest Lumbricidae abundance (18 individuals.m^-2). The highest abundance of earthworms (124 individuals.m^-2) was found in the soil of mounds created 30 years prior to sampling from the organic soil of the A_h horizon. The highest species diversity and low abundance were characteristic of areas between the mounds, the soil surface of which was greatly disturbed after removal of the A_h horizon to create those mounds. The degree to which the reforested clear-cuts created due to air pollution were overgrown with weeds contributed positively to the diversity and abundance of Lumbricidae.

Changbai Mountain Natural Reserve (1,985 km² and 2,734 m a.s.l.) of Northeast China is a typical ecosystem representing the temperate biosphere. The vegetation is vertically divided into 4 dominant zones: broadleaved Korean pine forest (annual temperature 2.32°C, annual precipitation 703.62 mm), dark coniferous forest (annual temperature -1.78°C, annual precipitation 933.67 mm), Erman's birch forest (annual temperature -2.80°C, annual precipitation 1,002.09 mm) and Alpine tundra (annual temperature -3.82°C, annual precipitation 1,075.53 mm). Studies of soil carbon (C) and nitrogen (N) mineralization have attracted wide attention in the context of global climate change. Based on the data of a 42-day laboratory incubation experiment, this paper investigated the relationship between soil moisture and mineralization of C and N in soils with different vegetation types on the northern slope of the Natural Reserve Zone of Changbai Mountain. The elevation influence on soil C and N mineralization was also discussed. The results indicated that for the given vegetation type of Changbai Mountain the C and N mineralization rate, potential mineralizable C (C0) and potential rate of initial C mineralization (C₀k) all increased as the soil moisture rose. The elevation or vegetation type partially affected the soil C and N mineralization but without a clear pattern. The moisture-elevation interaction significantly affected soil C and NO₃^--N mineralization, but the effect on NH₄⁺-N mineralization was not significant. The complex mechanism of their impact on the soil C and N mineralization of Changbai Mountain remains to be studied further based on data of field measurements in the future.

Analyses of root mycorrhizal samples and monitoring of fruiting bodies of macromycetes from Norway spruce stands at mountain and foothill localities in the Krkonoše and Orlické Mts. provided several data series allowing to assess and compare (albeit somewhat preliminarily) mycorrhizal conditions and macromycete incidence related to stand ages and location conditions. The overall mycorrhizal conditions in young (10 years old) and older (80 years old) stands on formerly agricultural soils are comparable to those in 80- and 90-year-old forests growing on standard forest soils, but young spruce stands in the Orlické Mts. replanted on forest soils do not surprisingly show any favourable mycorrhizal characteristics. The research documents a marked diversity of macromycete species composition in mountain spruce stands compared to foothill spruce stands on former agricultural soils. While in the younger mountain spruce stands of the Orlické Mts. the expansion of macromycete species composition began to develop in a similar fashion to that in the Krkonoše Mts., the comparison of older (80-year-old) stands on formerly agricultural soils in the Orlické Mts. foothills and Krkonoše Mts. implies that the macromycete species composition developed quite differently but with a similar success.

Studies were undertaken to investigate the composition, structure and diversity of four different types of North Mongolian montane forest near the southern border of the taiga. These forest types, classified as willow-poplar, larch-birch, spruce-fir and Siberian-pine forests, were found to be significantly different with respect to the elevational gradient. In the study area, two fire regimes could be distinguished at lower and drier elevations, frequent surface fires resulted in less diverse forests comprising coniferous species, which in their adult form were found to be fire-resistant, burn-colonizing and light-demanding deciduous tree species. In contrast, the forests colonizing the moist, higher elevations and shaded slopes had a higher diversity of tree species with greater basal area, higher proportion of deadwood, and more regenerating trees; here the coniferous shade trees experienced infrequent but destructive treetop fires. Overall, our results showed that the four forest types differed in composition according to the tree species, diameter and height classes.

The aim of this study was to investigate the wood density of Turkish hazel (Corylus colurna L.), an introduced species in the Czech Republic. Sample trees coming from a Czech site were tested for basic wood density and oven-dry density according to Czech national standards. Four sections were taken from each tree to evaluate the variability of wood density along the stem height and along the stem radius. The mean values for the basic density and the oven-dry density were 544 kg.m^-3 and 627 kg.m^-3, respectively. The results show that the highest density can be found in the bottom part of the tree, followed by a decline with the increasing height of the stem. For the radial direction from the pith to the bark, the pattern of density variability was more complex, reaching its highest value close to the cambium. Practically no correlation between annual ring width and density values was found out.

The paper deals with the analysis of price changes of roundwood (spruce, fir and beech sawlog, fuelwood) and energy wood in Slovakia, Czech Republic and Austria during the period of 2008-+September 2011. At the beginning of the article, the authors identify the major factors influencing timber price trends such as legislation regarding technical standards for the quality grading of round wood, global economic recession, incidental felling and political influence. Consequently, detailed analysis of timber price changes in selected European counties is provided by means of line graphs. The results of the analysis revealed that demand for wood and wood products began to decrease in mid-2008. The most critical situation was in 2009, primarily in the softwood market, when prices bottomed out. However, recent trends indicate a gradual rise in timber prices. In the future, a slight increase of timber prices is expected, however other factors (such as economic development, lobbyist pressure, incidental felling and many others) may influence prices, which makes it difficult to predict their trend.

The results of a fifteen-year period of investigations conducted on Norway spruce in the upper plateau of the Jizerské hory Mts. were summarised. The objectives were to evaluate the growth performance of an experimental plantation under harsh environmental conditions and assess the effects of amendments as well as the influence of the forest site variability on growth performance and survival of young spruces. The following treatments were distinguished: (1) lower control, (2) limestone and (3) amphibolite treatments on a less exposed slope of the ridge and (4) upper control on a summit of the mountain ridge. Principle characteristics such as mortality rate, height, annual height increment, stem base diameter, crown diameter and nutritional status were summarized and evaluated. Significant differences between treatments were recorded in heights. The trees fertilized with amphibolite were significantly taller than the control ones in thirteen out of the fifteen evaluated years and the applied limestone improved heights in ten years out of the fifteen evaluated years. A positive effect of amphibolite treatment on stem base diameter was proved in three of the four assessed years and was persisting till 2007 (last measurement of this characteristic), the positive effect of limestone was lasting up to 2006. The considerable role of the site variability was apparent from a comparison between the upper and lower control although they were in a very close position to each other, growth increment of the spruces on the ridge was significantly lower. Temporarily lower N concentration was recorded in the fertilized treatments in comparison with their respective control. The concentration of P was low and decreased to the limit of deficiency in all treatments, P seems to be the most limiting macroelement in the area.

Traditional land use has shaped the Mediterranean region for a long time and has resulted in present-day complex landscapes. The land abandonment dating from the 19^th century at a site located in the southwestern Alps (France) makes it possible to analyse how present-day forest stands inherit from past land uses. Tree composition and tree age structure were analysed in three stands resulting from different former land uses, i.e. ancient coppice, formerly grazed area and formerly tilled area. The ancient coppice contains the densest tree cover and is dominated by Fagus sylvatica, whereas the formerly ploughed and grazed areas are less dense, both dominated by Pinus sylvestris. Forest stand in the ancient coppice is older than in the formerly grazed area, and forest stand is the youngest in the formerly ploughed area. These stand differences are largely explained by former land use and the abandonment process. Albeit strong changes result from the land abandonment, these landscapes inherit aspects of their land use during the 19^thcentury at least and the dynamics does not match the expected pattern of soil fertility.

Currently, recreation is the most common use of protected areas and there are scarce data on the users and their opinion. The research was focused on visitors to the Blaník Protected Landscape Area (hereafter referred to as PLA), a well-known recreational area where data on visitors, important for PLA management, are missing. Therefore, the aim of the paper is find out: what kind of visitors comes to the study area; the type of forest trails and tourist facilities the visitors prefer. A questionnaire survey of forest visitors was used. Results show that the visitors mostly prefer maintained trails. According to forest visitors' opinion, the most convenient facility to place near the forest tourist trail is the nature trail panels. Furthermore, based on the acquired data, it was possible to create a visitor's profile which is important for respective research and other case studies in similar areas, and for managers of protected landscape areas to comply with both the visitors' needs and the needs of the protected area.

The foliar nutrient status was examined in a degraded Greek fir (Abies cephalonica Loud.) forest in Mount Parnitha near Athens, Greece. The examination lied in comparing the foliar concentrations of Ca, Mg, K, N, P, Fe, Mn, Zn and Cu with the critical values referring to conifers and the elemental percentages with regard to N of the forest with the corresponding percentages of a healthy Bulgarian fir (Abies borisii regis) stand, the closest relative of the Greek fir. It was found that the needles of the Greek fir had significantly lower concentrations from the N and P critical values. Significant differences were found for the Ca/N, Mg/N, P/N, Fe/N and Mn/N percentages. Significant correlations for the Greek fir were found between needle weight and foliar N as well as between needle weight and the percentages Ca/N and Fe/N. It is highly probable that N and P in the Greek fir are in short supply.

Increasing productivity and reducing cost in long-distance transportation have become increasingly important in the logistics of forest harvesting operations. This paper presents the research results of the performance of loading with Volvo 4500 BM and timber trucking using two types of common trucks in the Nav watershed in Iran. Both trucks can carry logs shorter than 7.8 m in length. The study used a time study based on empirical data for loads collected from one procurement district in the Nav watershed. The models included the following explanatory factors: driving distance, number of logs, and load volume. The time consumption and productivity of loading and timber trucking depends on several variables such as volume and number of logs per cycle. To evaluate the current transportation system in the Nav watershed, the empirical time study was conducted. Since transportation includes several phases and since many factors affect the work performance, significant variation in the total transportation time was observed. This makes planning and cost accounting more difficult. The models developed in the study are a promising way to support route planning and optimization, and cost and profitability calculation for trucking en­trepreneurs and the forest industry. The average productivity of log transportation was 2.84 and 3.4 m3.effective h-1 for the dump truck and chassis truck, respectively. The average hauling unit cost was 18 and 15 USD.m-3 in the dump truck and chassis truck, respectively.

This paper describes the forest fire dynamics in the city of Sanming in Fujian province, China, from 2000 to 2009 with a view to understand the number of fires and burned areas in different counties. It also includes the spatial-temporal distribution of fires and application of the Canadian Forest Fire Danger Rating System (CFFDRS). Daily forest fire data was provided by the Department of Wildfire Prevention of Sanming Forestry Bureau. FWI calculator v.7.0.2.76 was used in this study for analysing the weather parameter data. The results showed that a total of 818 fires and burned areas of 8721.16 ha were found during the study period of 10 years. However, the highest and lowest forest fires were found in Youxi county and Sanming district, respectively. Most of the fires with large burned areas occurred at 2 p.m. Moreover, occurrences of fires were found the highest and lowest in March and June, respectively. Based on FWI calculation, the highest danger rating value was found in March, 2009. This study proposes that it would be possible to manage regular forest fire occurrences through the application of CFFDRS. Finally, to plan the fire prevention and management in southern China and other tropical countries, this system has a great opportunity for further implementations.

Only two cambioxylophagous species (Ips amitinus and Pityogenes chalcographus) were found on sections of Picea pungens and Picea abies that belong to economically important pests of Norway spruce. Representatives of the Isarthron sp. (Cerambycidae) were developed on the examined sections of both P. abies and P. pungens. The monitoring of attractiveness of the spruce species P. pungens and P. abies to cambioxylophages revealed that P. pungens was more intensively attacked by I. amitinus while P. chalcographus was more abundant on P. abies. Both bark beetle species preferred shaded parts of tree trunks, although their development was more successful on the sun-exposed side. On P. pungens, abundance of P. chalcographus decreased and abundance of I. amitinus increased with increasing trunk volume. Blue spruce was more attractive to Isarthron sp. compared to Norway spruce.

The present study examines the relationships between the indicators of tree species and structural diversity and the quality of timber production in young even-aged forest stands with the average age below 40 years. The study is based on the forest inventory data from University Forest Enterprise Kostelec nad Černými lesy, Czech Republic, performed from 2009 to 2011. The examined young stands were recorded in 256 sample plots representing 21.2% of the enterprise area. On each sample plot, we quantified 171 partial biodiversity indicators. In total, we analysed 16,416 different variants of the relationship between the diversity indicator and the quality of timber production. The analysis revealed that similarity indicators such as the range of tree heights, Canberra distance, Bray and Curtis index, and index of species evenness and heterogeneity were the most frequent basic indicators occurring in significant correlations. The results indicate a positive relationship between the proportions of assortments in quality classes I to IV and stand diversity expressed by the number of tree species and Canberra distance.

The reaction of five apple cultivars to olive wilt caused byVerticillium dahliae Kleb was evaluated. Five apple cultivars (Royal Gala, Delicious Anabri, Double Red, Golden Delicious, Granny Smith) and one olive cultivar (Nabali Mohassan) were inoculated with V. dahliae and grown under partially controlled greenhouse conditions. Typical symptoms of the disease were developed on the inoculated olive seedlings. However, all tested apple cultivars did not show the typical symptoms of Verticillium wilt except cv. Delicious Anbari, which showed 8.31% disease severity. The average percentage of disease severity was 61.2% in Nabali Mohassan. The pathogen was positively re-isolated from the inoculated seedlings of cvs Nabali Mohassan and Delicious Anbari after 12 months from the inoculation date. Results indicate that an apple plantation to replace dead or severely diseased olive trees infested with Verticillium wilt is an appropriate low-cost and environmentally sound IPM alternative approach to control Verticillium wilt.

The literature linking Bt maize versus non-Bt maize and the changes in the fungal microflora spectrum and in the mycotoxins content have been summarised. The European corn borer reportedly promotes the infection of maize by Fusarium spp. Stalk and ear rots caused by Fusarium spp. are often related to mycotoxin accumulation in maize kernels. As a result, food and animal feed from maize are more severely contaminated with Fusarium mycotoxins: e.g. fumonisins (FUM), deoxynivalenol (DON), and zearalenone (ZEA). Mycotoxins in field maize lead annually economic losses of hundreds of millions of dollars in all regions of the world. The insecticidal proteins in genetically modified hybrid Bt maize reduce insect damage caused by certain Lepidopteran larvae, which in turn can reduce the infection of the grain by the mycotoxigenic fungi. Where such insect damage is a major factor in mycotoxin contamination, Bt maize can lower mycotoxin levels in many cases. The protection of maize plants against insect damage (European corn borer) through the use of Bt technology seems to be one of the ways to reduce the contamination of maize by Fusarium species and mycotoxins.

In Europe, glyphosate resistant populations have developed in some weed species in perennial crops, including three species of the genus Conyza documented by the International Survey of Herbicide Resistant Weeds. Conyza spp. biology is reviewed in this paper and related to population dynamics and the development of resistant populations. Suboptimal growth stage at application, improper agricultural practices such as overreliance on glyphosate and long-term use of sublethal doses are identified as the most important factors of resistance development. Current control methods in perennial crops including mixtures of glyphosate with other active ingredients are discussed and effective weed management strategies are described to manage the development and spread of glyphosate resistant Conyza spp. in Europe.

Identification of Meligethes species and their frequencies in adult samples collected at different localities in Central and South Moravia (Czech Republic, 2009-2011) was based on comparisons of morphometric and colour characters and on differences in male and female genitalia. M. aeneus, M. viridescens, M. subaeneus, M. atratus, and M. coracinus were recorded throughout the observation period, while M. nigrescens was recorded just in 2009 and 2011, M. carinulatus and M. maurus in 2010 and 2011. M. aeneus was the most frequent species of all compared samples (2009-2011). Of the accompanying species, M. subaeneus and M. viridescens were markedly more frequent in this study. Considering high resistance of M. aeneus to esteric pyrethroids, it could be helpful to distinguish among the individual Meligethes species occurring in field samples intended for laboratory testing.

In semi-arid regions of the United States, Pyrenophora semeniperda kills seeds of the winter annual Bromus tectorum. We report on pathosystem outcomes under manipulated water potential and temperature environments commonly observed within semi-arid environments for dormant and non-dormant seeds. We propose a range of outcomes for infected seeds. During summer, seeds remain dormant and are killed across a range of water potentials. During autumn, seeds survive by rapidly germinating or are killed if radicle emergence is delayed by intermittent hydration. In winter/spring, secondarily dormant seeds can be killed by the fungus. The only likely scenarios where seeds escape death include absence of infection (autumn, spring, or following autumn, germination) or infection in autumn when seeds germinate rapidly.

The study was focused on the wild pathosystem Lactuca serriola-lettuce downy mildew (Bremia lactucae) and lettuce powdery mildew (Golovinomyces cichoracearum). Observations were focused mainly on recording natural infection of prickly lettuce (Lactuca serriola) by downy and powdery mildews in the East Bohemia and Moravia (the Czech Republic) in the May-September period of 2007-2011, and on the influence of environmental conditions on disease incidence. Only data for July and August were used for the detailed comparisons of occurrence of both pathogens, because intensity of disease in this period was the highest. Data were linked with the average monthly temperature and rainfall rate in the Czech Republic. G. cichoracearum prefers rather low levels of precipitation and temperatures around 20°C, therefore significantly higher incidence of this pathogen was recorded in August 2007. On the other hand in July 2009 and 2010, when the intensities of precipitation were higher, incidence of Bremia lactucae prevailed. In August 2010 and 2011 incidence of both pathogens were more or less similar at all locations. Our observations showed that climatic conditions influence the incidence and prevalence of both pathogens in weedy growing populations of Lactuca serriola.

Well-aerated and alkaline soils are proven to lack plant-available iron. Fe-efficient plants, however, induce morpho-physiological and biochemical mechanisms of adaptation. These changes in morphology and physiology of the shoot-root systems of peanut (Arachis hypogaea L. cv. NC 2) plants were studied by cultivating them hydroponically in the nutrient solution containing different levels of Fe³⁺EDDHA (0.00, 0.125, 0.25, 0.50, 1 and 2 ppm). Three types of chlorosis and regreening (I, II, III) on the shoot system appeared simultaneously with three types of rooting (I, II, III) in different stages of plant growth under Fe-free media. The difference in the regreening processes of plants grown in Fe-free and Fe-treated media indicated that their signaling pathways for Fe localization might be different. The morphological responses were found to correlate to three types of regular and rhythmic pH changes in the nutrient solutions. The sites of pH responses and Fe³⁺ reducing activities in the roots showed dependence on the type of root and shoot morphology.

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

To investigate the environmental advantages of using grass-clover binary mixtures over pure stands as winter cover crops, a serial of five field experiments (each designed as randomized complete blocks with four replicates) was carried out in eastern Slovenia. Trifolium incarnatum L. and Lolium multiflorum Lam. were sown in late summer as pure stands and binary mixtures. Pooled data calculated from all the experiments revealed that the soil mineral N in spring and accumulation of N by plants decreased with decreasing proportion of T. incarnatum in the binary mixtures, while the C:N ratio of cover crop organic matter increased. C accumulation was the highest when the seeding ratio of the binary mixture of T. incarnatum and L. multiflorum was 50:50. In the C and N environmentally sustainable management efficiency coefficients, three important traits of winter cover crops for environmental pro-tection were given equal importance (low soil mineral N content in spring, high C accumulation in plants, and high N accumulation in plants). The coefficient was higher for binary mixtures of T. incarnatum and L. multiflorum than for pure stands of these crops, proving the complex environmental advantages of binary mixtures over pure stands.

The tolerance, accumulation and subcellular distribution characteristics of cadmium (Cd) in ramie (Boehmeria nivea L. Gaud.) were investigated using a 2-year field experiment. The results indicated that ramie has a certain extent of tolerance to soil Cd (≤ 20 mg/kg) contamination with no significant decrease in shoot biomass and fibre yield relative to control conditions. Although ramie did not hyperaccumulate Cd, it accumulated considerable amount of Cd in the aboveground parts (approximately 0.19 to 1.09 kg/ha annually). The Cd contents retained in ramie tissues were found in order of roots > stems > leaves. Further, regarding the subcellular distribution of Cd in ramie tissues, 80% of the total Cd was bound to the cell walls of the roots and stems, whereas in leaves the proportion of Cd stored in the cell wall fraction was around 60% and a lesser amount of Cd was stored in the soluble fraction (24.1-25.5%). Our collective results indicated that ramie adapts to Cd stress via the store of a large amount of Cd in cell walls, and suggested potential usefulness of ramie in the phytoremediation of Cd-contaminated farmlands.