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This paper evaluates the development of growing stock, number of trees and diameter distribution of the standing volume in the Opuky locality where conversion to a selection forest has been the aim of management over a long period of time. With respect to species composition, the stand is divided into two plots. The initial condition and development of both plots differed. The favourable initial composition of the stand has gradually deteriorated due to delay in natural regeneration and therefore recruitment of young trees over a long period. The total number of trees on both plots has been low for target diameter of 51 cm. On the other hand, the growing stock has exceeded the model condition. The proportion of broadleaved species in the stand gradually increases, reducing the possibility of conversion to a selection forest in future.

Chrysopids and Hemerobiids were studied using Malaise traps in young spruce forests in the eastern part of the Czech Republic. A total of 12 species were found. The most abundant species were eurytopic Chrysopa carnea, Chrysopa perla, Hemerobius humulinus and Hemerobius pini associated with conifers. The seasonal flight activity of these species is discussed.

In the paper, there is described using of the optimization models AGRO-3 SR for modeling food production chains in the Slovak Republic (the modified version of the Czech model AGRO-3) and ALOKA for optimal allocation of the domestic agricultural production computed by AGRO-3 SR into 4 different regions of the SR for simulation of consequences of various types of agrarian policies on the effectiveness of the Slovak agriculture to the medium-term horizon 2005. There are formulated and evaluated 4 scenarios for the model AGRO-3 SR and two alternatives A and B for the model ALOKA relating to all scenarios. Results of simulations have shown that the best result was reached in the scenario 4 by the price liberalization in the whole food chains.

The paper is a part of the solution of the research plan of the FBE MUAF in Brno, No. GAMSM 431100007, and it is focused on the analysis of factors influencing competitiveness of the wine-growing and viniculture. This paper is based on the hypothesis that the competitiveness of the viniculture and wine sector could be influenced, amongst other things, by specific national conditions as defined by "Porter's diamond". This essay deals with factor conditions like the total area of vineyards, the average per hectare yield of grapes, the total wine production and wine consumption including the foreign trade with this commodity. The comparison of the chosen national conditions is made within the EU member states and also within six candidate countries - Cyprus, Estonia, Hungary, Poland, Slovenia and the Czech Republic.

Human resources are a key factor in the development and competitiveness of organisations. The concept of organisation's intellectual capital enables a complex and systematic look at the decisive organisation sources (including human resources). Talents - people with management skills and the so-called project talents play an important role within the frame of human resources. Talents - bearers of special endowments and abilities - are a decisive factor in the growth of the organisation. Partial probes carried out in agribusiness organisations have confirmed the significance of both theoretical concepts. At the same time, they have revealed that organisations utilise various kinds of talents the differentiation of which requires a more profound examination and analysis in order to assess, in a competent way, the contents and forms of education of young professionals, as well as the contents and forms of lifelong education in the field of agribusiness.

The major insect pests on rice in Tanzania are listed and described. They are from five orders (Coleoptera, Diptera, Hemiptera, Lepidoptera and Orthoptera) and are discussed as stem borers, stem and root feeders, and leaf and panicle feeders. This review puts together the hitherto fragmented information available on the distribution, host range, biology/life-cycle and ecology, and the management measures of the insect pests of rice. Areas for future research are also mentioned.

Results of researches carried out in 2000 and 2001 have demonstrated, that main factors determining yield of winterwheat are: agrotechnical measures, mainly proper choice of field, optimal nitrogen fertilization as well as choice ofcultivar well adapted to local climatic conditions. Chemical protection of winter wheat affects first of all stability ofyield. Regular inspections of fields with special account to present phytosanitary situation, thresholds of noxiousness andexpected development of disease and pest populations should decide on the need of chemical treatments.

Water regimes of extensively used grasslands (one cut per year, two cuts per year, no cut, mulching) were determined and compared by drainage lysimeters in 1998-2000. Although the botanical composition and yields of experimental swards were different, there was no statistically significant difference in their water regime (only the soil moisture content of no-cut variant was significantly higher than in other variants). A determinant factor for the water regime of grasslands (GR) is the sum of rainfall over the growing season while the GR water regime is influenced by land use immediately after the cut. Water runoff from the soil profile 0.0-0.60 m (water supply to the groundwater level) was found to be negligible in the growing season, a substantial groundwater recharge occurs in an off-season period and/or at the beginning of growing season. Mulching was not proved to reduce evaporation. The best type of management providing for the economical water regime appears to be a one-cut variant. Relationships between botanical composition and GR water regime are also described.

Seven cultivars of common buckwheat were tested in field trials under two levels of nitrogen fertilisation on two experimental sites during 1998-2000. The aim of the experiments was to evaluate the influence of cultivar, nutrition and year on main technological quality parameters (thousand achenes weight, volume weight, proportion of fractions on sieves 4.5 and 4 mm, proportion of husks and yield of groats). The differences were observed between buckwheat cultivars in all observed parameters of technological value. Nitrogen fertilisation before sowing (50 kg.ha^-1) did not influence any parameter. On the contrary, buckwheat technological value was influenced by sequence weather (particularly rainfalls) during flowering and achenes formation periods (July). The influence of year was manifested especially on development of endosperm and husks of achenes. Better growing conditions on experimental site Uhříněves caused lower values of volume weight, lower proportion of pericarp (husks) and considerably higher proportion of fraction over 4.5 mm.

Many factors, most notably climate, soil, genotype and fertilising, can influence barley grain composition and its nutritive value. The aim of the research was to evaluate the impact of mineral N rate in different management systems in the static long-term experiment with three years field rotation of grain maize, wheat and barley on the chemical composition of winter barley and its nutritive value for ruminants. Crude protein content and metabolizable crude protein content were increasing with increased mineral N rates. Higher yield meant lower crude protein and metabolizable crude protein content in all mineral N rates. The average crude protein content of barley grain, presented in DLG tables (1997), which is 12.4%, was in MM and SM reached by fertilising rate 110 kg N/ha. A significant impact of mineral N fertilising on crude ash, ether extract and crude fibre content could not be confirmed, nitrogen-free extract content was decreasing with increased mineral N rates. A significant impact of the management system on the Weende analysis parameters, net energy for lactation, metabolizable energy and metabolizable crude protein could not be confirmed. At both analyses a significant impact of the season was confirmed on crude protein content and nitrogen-free extract content. Although the protein content was increasing with increased mineral N rate from 9.2-14.2% (for 35%) ME content and NEL content did not significantly differ considering mineral N rate; ME/ha and NEL/ha increasing with increased mineral N rates was the result of the yield increasing with increased mineral N rates.

The aim of this study was to develop a protocol for production of polyploid M1-generation plants of Viola × wittrockiana Gams. Two variants of colchicine treatment were compared for their efficiency. Early detection of novel ploidy levels was achieved by screening of stomata size, leaf index value (leaf blade length/width), and other morphological characteristics of the M1-generation. Secondary screening for novel ploidy levels was performed by flow cytometry (FCM). Hexadecaploid, aneuploid, and mixoploid plants were successfully identified by FCM.

Differentiation of forest technologies according to ecosystem properties is a necessary step to achieve sustainable forestry. A forest typological system is considered to be the basic unit of ecosystem differentiation in the Czech Republic. Terrain characteristics, potential water erosion and applicable harvest technology were examined for 44 forest sites in a landscape segment of the Jizerské hory Mts. Forest site was found homogeneous in terms of terrain and technological properties. Edaphic category and groups of forest types as higher classification units and management sets as units of alternative classification showed lower homogeneity insufficient for operational planning.

Pythium oligandrum Drechs. belongs to the order Oomycetes. It is parasitic on many fungi from the same or other orders. The antagonism of P. oligandrum is a multifaceted process dependent on the target species involved. P. oligandrum is nonpathogenic on 12 species of crops from six families. It does not attack their tissue but occurs on the root surface, predominantly in the regions of hypocotyl - taproot, together with plant pathogenic fungi. It utilises the root exudates and fungus hyphae on the root surface, including those of the plant pathogens, for its own support. A growth stimulation of plants was observed. P. oligandrum can be utilised for biological control on a wide spectrum of crop plants. Different methods of application have been developed. The effect of a mycoparasite preparation is more preventive.

First outbreaks of fire blight were detected in Austria in 1993 and in Hungary in 1995. 137 Erwinia amylovora isolates were compared by PCR-RFLP, sequencing of the repeat region of the PstI fragment of plasmid pEA29, RAPD and AFLP analysis. Differences of repeat numbers in first isolates were observed. Six isolates showed different RAPD profiles. In AFLP analysis, so far, no differences in fragment pattern were determined. Pathogenicity tests with micropropagated apple cultivars revealed differences in plant susceptibility and in virulence of isolates. Responses of Malus tissue were visualized by the use of epifluorescence microscopy through the localization and the production of substances involved in cellular defence mechanisms (e.g. flavonoids, lignin) in various susceptible cultivars. The effect of bacterial strains differing in pathogenicity is shown by cellular peroxidase and flavonoid production.

Leaf spot pathogen is characterized as a highly developed parasite after investigation of development peculiarities of the fungus in pure culture and natural conditions. The degree of correlation depended on the medium. Impact of incubation temperature on Blumeriella jaapii (Rehm) Arx growth was different. Fungi colonies formed more intensively and their diameter increased significantly under higher temperature. Optimal conditions for the disease prevalence are 15-20°C and moisture. Relative humidity and precipitation influenced maturation of ascomycetes and discharge of ascospores (r = +0.89). Microscopic analysis of leaves showed that during winter thaw, when the average temperature is about 0 ± 5°C and relative humidity is higher than 70%, was possible to detect mature ascomycetes and conidia. It is possible to affirm that lower temperature than it was assumed is sufficient for formation of ascomycetes.

The effectiveness of fenarimol and difeconazole, DMIs fungicides, and dodine was tested in two experimental orchards and in greenhouse in two seasons. In 2001 monitoring of resistance to dodine was conducted also in some commercial orchards located in main apple production. In both experimental orchards fenarimol gave significantly poorer control of apple scab than difenoconazole when curative treatments were applied. The same results were obtained in greenhouse tests using for inoculation the suspension of conidia of V. inaequalis from these orchards. In many monitored orchards, in each region, a high level of dodine resistant isolates in population of V. inaequalis (even more than 40%) was noted. Only in six from 65 tested orchards there was less than 1% resistant isolates in population of the fungus.

In the framewort of the quantitative histologic evaluation of poultry products, the size and the number of bone fragments have been determined using the image analysis. Bone fragments were identified by their colour and analysed automatically. The samples contained 135 to 2167 bone particles the length of which varied from 5 to 2088 μm. Comparing products of the same kind, we found differences in the contents of bone fragments; this fact was possibly due to inadequate observance of the technological procedure by some producers.

Method ISTA SDS-PAGE was used for separation, detection and evaluation of high molecular weight glutenin subunits (HMW) in the different wheat species. The relation has been studied between the HMW glutenin subunit alleles and the bread-making quality of 25 world wheat cultivars and 21 regional varieties common wheat varieties (Triticum aestivum L.), 17 winter spelt wheat (Triticum spelta L.), 3 durum wheat cultivars (Triticum durum DESF.), 9 cultivars of Triticum turgidum L. and 5 cultivars of Triticum polonicum L. The highest frequency of occurrence of HMW glutenin subunits 2*, 13 + 16 and 5 + 10 were found in world wheat cultivars. In Slovak wheat varieties were analysed subunits 0, 7 + 9 and 5 + 10, 2 + 12. The HMW subunits 0, 7 + 8 with Glu-score 4 were determined in Triticum durum DESF. Three electrophoretical profile groups of different HMW glutenin subunits were found in Triticum turgidum L. and Triticum polonicum L. and six electrophoretical profile groups were determined in Triticum spelta L. The verified correlations between bread-making quality and specific HMW subunits of glutenin can be utilised by wheat breeders using SDS-PAGE of proteins as a screening test for the prediction of bread-making quality of wheat.

The goal of the investigations was to assess the average contents of heavy metals (Pb, Zn and Cd) in the surface soil layer (0-30 cm), in drainage water and their uptake by growing plants, in the experimental amelioration field for four different variants of drainpipe spacing (15, 20, 25 and 30 m) during the three-year period. Maize and winter wheat were grown in all variants throughout the trial period. In all variants of drainpipe spacing, heavy metals in soil, drainage water and plant material were within the limits. The highest average level of Pb was 13.5 mg/kg, Zn 88 mg/kg and Cd 0.7 mg/kg in soil. Drainage water concentration of heavy metals was below 50 µg/dm³ for Pb, below 2 µg/dm³ for Cd, while the highest average value of Zn amounted to 20 µg/dm³. In grain of the crops grown, the concentration of Pb was below 0.4 mg.kg-1 and that of Cd below 0.1 mg/kg.

The paper deals with problems of thinnings in a mixed stand (spruce-fir-beech) situated in the sixth altitudinal forest zone. Three of the five investigated plots were tended by free crown thinning for a long time, and two were left without any planned silvicultural treatments as control. Dynamic changes in tree species composition, stand structure, qualitative and quantitative production were evaluated for a period of 30 years. The changes were compared with respect to differences between the plot with long-term silvicultural treatments and the control plots (without treatments).

The old debt problem resulting from the transformation of the agricultural co-operatives of the former GDR (German Democratic Republic) is described with respect to its evolution and its economic policy treatment during the process of transformation. So far, the measures for the treatment of old debts have had business economically stabilising effects. Nevertheless, debts are still growing. The farms which are affected by such old debts are strongly interested in solving this problem. This explains the intensity of the results' discussion of a scientific expert opinion on an analysis of the mode of action of the old debt regulation in agriculture. The conclusions which can be drawn from the public discussion of these results with respect to the future treatment of these old debts show, that the affected farms favour a kind of bonus rule for debt repayment. Such a regulation also seems to be acceptable for the treasury as the final bearer of the remaining debts and as a solution to minimise the taxpayers' burden.

The objective of this study was to establish the genetic relationship among cultivars commonly used as donors for resistance to Plum pox virus (PPV) in order to identify the putative sources of resistance to PPV. The plant material tested represented the European, Central Asian and Chinese ecogeographical groups of cultivated apricots as well as the wild Dzhungar-Zailij population of Prunus armeniaca L. Forty-eight native accessions as well as the resistant (or tolerant) cultivars Harlayne, Stark Early Orange (SEO), Goldrich, Vestar and two hybrid forms Vestar × SEO (LE 3276) and Velkopavlovická × SEO (LE 2904) were screened by means of SSR analysis. To elucidate genetic relationships among apricot germplasm, a dendrogram was produced using neighbor joining (NJ) analysis of Nei's pair-wise genetic distances over 14 polymorphic SSR markers. On the dendrogram, resistant cultivars were separated into two different clusters suggesting two different sources of resistance to PPV. As was expected from pedigrees, SEO, Vestar, LE 2904 and LE 3276 were grouped together in a cluster adjacent to the European cultivars. Resistant cultivars Harlayne and Goldrich were within another group containing Central Asian apricots and Dzhungar-Zailij form.

It is indispensable to have accurate and speedy method of nematodes detection considering their great deal of malignancy nematodes. For identification of Meloidogyne incognita genetic primers were designed and the procedure was attested by Polymerase Chain Reaction.

Effect of temperature on growth and antagonistic ability of Trichoderma spp. isolated from local strawberry culture and commercial product, against Rhizoctonia solani, strawberry pathogen, was studied in vitro. Trials were carried out twice, at 10, 25 and 30°C. Inhibitor effect was evaluated by radial growth measures of established duals on PDA's dishes, using Royse and Ries formula, to evaluate the percentage inhibition of radial growth. Design of dishes was a randomized complete block, considering 10 replicates. Data were analyzed statistically by two-way analysis of variance. The objective has been to determine the most competitive Trichoderma strain and the best temperature that produce the inhibiting effect on the pathogen growth. Local strain has the best behavior at 10 and 25°C.

Two samples of commercial wheat flour from the last year's harvest were stored for three months (in the period from November to April) under different conditions. The ambient temperature and humidity varied during the storage in the dependence on the year season. Certain analytical characteristics (moisture, wet gluten and its extensibility, acidity and falling number) and alveograph behaviour of flour were determined at regular intervals. Flour moisture, acidity, and falling number changed with the time of storage but no explicit influence of the storehouse conditions and the initial flour properties was proved. Viscoelastic properties of weaker flour samples changed during storage more markedly than those of stronger flours in the sense of a significant improvement of their quality.

Five cultivars of spelt wheat (Rouquin, Bauländer Spelz, Schwabenkorn, Franckenkorn and Holstenkorn) have been evaluated for baking quality by means of direct and indirect indicators. Three-year values of the indirect indicators have been statistically processed by the analysis of variance. Based on the results obtained we can say that all evaluated indicators except the extensibility of gluten were significantly influenced mainly by the year of growing. The cultivar itself was a less important source of variance, although some values of important indicators differed significantly according to cultivars. Based on indirect indicators such as the content of wet gluten, its extensibility and swelling, the content of N-substances, the sedimentation test in the modification with SDS, the falling number and the content of starch, the cultivars Schwabenkorn and Rouquin are considered as the most suitable and of the highest quality. In general all the cultivars of Triticum spelta L. showed high contents of N-substances (x = 15.46%) and wet gluten contents (x = 37.12%). Their disadvantages are lower swelling values (x = 9.3 ml) and lower sedimentation values (x = 37.4 ml) which have a negative influence on the bread volume and the specific volume (under 310 ml.100 g^-1). The predicted good baking quality of Schwabenkorn has been comfirmed in a baking experiment (direct method of evaluating the baking quality). There were good baking quality results for Bauländer Spelz as well. Unexpectedly bad results have been found with Rouquin, which showed the lowest water absorbing capacity of flour, the lowest bread volume, specific volume and baking extraction. The bread was just acceptable as far as taste is concerned. The baking from Holstenkorn was evaluated as excellent.

The effect of addition of treated sewage sludge on the accumulation of Zn in plants was tested in pot experiment. The additions of eight months preincubated sewage sludge at temperature of 20°C under aerobic and anaerobic conditions with addition of peat and straw were tested. Two different combinations were designed: first consisted of 50% sludge + 35% peat and 15% straw, and second was made of 50% sludge + 5% peat and 45% straw (expressed as dry matter). Three different soils Chernozems, Luvisols, and Fluvisols and three sludges were tested in the experiment. Oat (cv. Pan) was planted as experimental crop. All treatments were fertilized by NPK. Green biomass of oat was harvested and analyzed. At treatments with addition of both composted sludges pH dropped down causing higher mobility of Zn in sewage sludge. Oat grown in these treatments contained higher amount of Zn compared to untreated soils. The application of anaerobically treated sludge led to increased Zn content in biomass compared to aerobically incubated one. Predominant effect on Zn accumulation in plants was determined by tested soil. The highest content was determined in plants grown on Fluvisols. The biomass yield was more affected by source of sewage sludge than by the soil type used. Treatments amended by anaerobically incubated sludge showed tendency to higher biomass production due to their higher content of nitrogen and carbon.

In 1997-1998 virulence of the wheat leaf rust population was studied on Thatcher near isogenic lines with Lr1, Lr2a, Lr2b, Lr2c, Lr3. Lr9, Lrll, Lrl5, Lrl7, Lrl9, Lr21, Lr23, Lr24, Lr26 and Lr28. On these NILs 11 pathotypes were determined in 1997, and 8 inl998. All rust samples were avirulent onLr9, Lr19, Lr24 and Lr28.There was a relatively low frequency of virulence on Lrl, Lr2a and Lr2b. Most rust samples were virulent on Lr2c, Lr11, Lr15, Lr17, Lr23 and Lr26. All samples were virulent on Lr3 and Lr21. The identified pathotypes conformed with races 61SaBa*, 77SaBa, 2SaBa, 12SaBa, 57SaBa, 6SaBa, 61*, 77 and 6. Races 61SaBa*, 77SaBa and 2SaBa prevailed in 1997, races 61 SaBa*, 77SaBa and 12SaBa were prevalent in 1998. Races 6 and 6SaBa were found for the first time. Data on Lr genes in recently registered winter wheat cultivars are presented.