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An evaluation of the linear description of type in 494 horses of the Old Kladrub breed for 32 traits was used to analyse the effect of variety, stud, sex, year of birth and age at description. A linear model with fixed effects was used. The highest coefficient of variation was calculated for the forelimb side-view (40.14%), chest girth (36.25%) and height at withers (30.97%). 28 out of 32 traits were in the range from 7 to 9 utilized scores. The descriptor used a very high number of scores of the scale. Significant differences between both varieties were found in 13 out of 32 traits. Significant differences were found in 12 out of 32 traits between the Kladruby stud farm and the private studs. There is no reasonable explanation of this fact. A significant variety × stud interaction was recorded in only 7 traits. Significant differences between stallions and mares were recorded in a large number of front and body traits (in 11 out of 18 traits) and in 2 rear traits. Despite of a remarkable number of significant differences between the years of birth (in 18 out of 32 traits) and age at description (in 13 out of 32 traits) both factors are not the important ones for the selection of horses according to the type traits. The description of type traits, performance recording and selection are carried out in the population of four-years-old horses born in the given year. The age at description does not play a role because all horses are now described each year at a standard age of four years. The linear description of type is an important tool for the breeding and conservation of genetic diversity within the breed.

This study was aimed at monitoring the relative and absolute stand heterogeneity of total carbon, total nitrogen and C/N ratio in Ah-Ae-Btg-Bt horizons of Gleyic Luvisol on one mountain meadow divided into two study plots: one moderately (once a season) mown (plant community of the Nardo-Callunetea class) and one abandoned for about 12 years (plant community of the Molinio-Arrhenatheretea class). The heterogeneities were evaluated more than 2 months after the mowing of the moderately mown meadow at the end of July 2005. Relative stand heterogeneity was expressed using coefficient of variation (CV), absolute stand heterogeneity using the differences between maximum and minimum value. When both meadows were taken into account, the relative stand heterogeneity of total carbon in individual horizons was < 65%, < 73% (total nitrogen), and < 93% (C/N). Lower relative and absolute stand heterogeneity of these parameters was mostly on the abandoned meadow. Relatively higher differences of stand heterogeneity between the meadows were evident in deeper parts of the soil (horizon Btg) and the lowest mainly in horizon Ah (or Bt). The accelerated accumulation of dead organic matter in the autumn caused the natural difference of these inputs not to be substantially eliminated by the presence or absence of mowing. Accelerated eluviation of organic compounds of higher nitrogen content significantly (P < 0.05) decreased the C/N ratio in the Bt horizon (n = 6-8) of the abandoned meadow.

Slow-Release Fertilizers (SRF) Silvamix Forte and Silvagen were tested in two-year experiments with container-grown woody plants (Pyracantha coccinea, Thuja occidentalis). Several fertilizing systems were compared: preplant application of SRF into substrate as the sole nutrient source for a two-year period, preplant application of SRF and soluble fertilizer (PG Mix), and preplant application of SRF and soluble fertilizer together with additional fertilizing by solution of nitrogen fertilizer during both growing periods. A system with controlled-release fertilizer (CRF) Osmocote 5-6 was chosen as a control variant; it was incorporated into substrate before planting in the first year and top-dressed in the second year. CRF Plantacote 6M (mixed into substrate before planting and top-dressed in the second year) and Osmocote 16-18 applied only before planting were tested, too. The experiments showed that SRF Silvamix Forte and Silvagen give results comparable with CFR provided that they were incorporated together with soluble ferti-lizer dose and plants were fertilized by solution of nitrogen fertilizer during both growing periods.

Significance of a short-time survival test for the prediction of quality parameters of sperm obtained by gradient centrifugation was evaluated from an aspect of their functional resistance. Frozen semen samples from 27 bulls before and after separation were assessed by a 120-min survival test. The evaluation of morphological examination of ejaculates was carried out using the SASMO computer program. Statistically significant interrelationship between sperm quality parameters in the initial insemination doses, the amounts of obtained sperm after separation and their functional and vital resistance in the survival test was documented.

Management can be understood as a "bonsai" integrating its roots in long-term bases with the trunk of general management growing from it supporting a cultivated treetop branching out in the real time. Managers need to develop a new understanding of the management process that will respond to global trends in the world's economy. More precisely it needs to create more progressive management styles. Management will be successful if it is based upon people's own knowledge and their development. In addition it has to look beyond the confines of the company and even of the country and to take into account the on-going and permanent development of technology. With particular regard to technology, man should be seen as a bearer of knowledge, regarded as an investment and seen as a source of long-term profit.

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

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

We conducted a pot experiment to evaluate the Cd and Zn accumulation in leaves and roots of Salix smithiana (BOKU-03DE-001) and S. caprea (BOKU-01AT-004) clones grown on a metal-contaminated soil as affected by native microbes extracted from the same experimental soil, and the fungus Cadophora finlandica. Plant biomass production of S. smithiana was decreased in all the treatments compared to the sterilized control. In contrast, S. caprea grew best on the non-sterilized soil. Similar effects were observed for plant Zn and Cd contents. Microbial treatments affected metal accumulation differently in the two Salix species. The effects of the microbial treatments on biomass and metal content of leaves were not related to the degree of mycorrhization. A comparison with literature data suggests that the plant response to microbial inoculation in terms of metal accumulation may depend on the plant-internal metal concentration. Our findings also illustrate a difficulty of successful rhizosphere management using metal-tolerant microbial isolates to further enhance the phytoextraction process.

In our work, we focus on the evolutionary studies of sex chromosomes. As model organisms we use several species of the plant genus Silene. An important part of our research is represented by genetic mapping based on the assays of DNA length or sequence polymorphisms. Apart from the other methods we also use the dCAPS method, which is very useful for detection of the sequence polymorphisms (SNPs). This method is unique as it is able to detect SNPs that are not situated in any restriction site; a fundamental principle of this method is usage of primer designed with one or two mismatches that bring into the target sequence the mutation in vicinity of SNP. Using this method, we found out some improvements that can make analyses more cost-effective.

Potassium is one of the most important nutrients for plants and its content in the soil should be monitored. In the precision agriculture, which is recommended now, the ion selective electrodes are tested to determine chemical properties of the soil. The objective of this work was an evaluation of use of the valinomycin-based ion selective sensors for determination of assimilated potassium in Egner-Rhiem soil extracts. Flame photometry was used as a reference method. Results obtained from potentiometric and photometric methods in soil extracts correlated linearly (R² = 0.84). Analysis of soil extracts by the ion selective electrodes is simple and there is not a need for calcium ions precipitation.

The paper refers to the possibilities of the evaluation of the wind erosion risks by using a model created in GIS. The model exploits the pedological information database for determining the potential risks of soils by wind erosion. The following data are the database of the agricultural land use, meteorological data and the topographic maps for determining the direction of wind and climatic conditions. Using the data transferred to the graphic form, it is possible to create the digital terrain model and to regionalise the meteorological data. Consequently, the wind barriers are localised in the landscape and it is possible to create the zone of efficiency around each barrier (protecting the land from the erosive effects of the wind) according to the characteristics of their height and density.

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

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

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

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

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

The aim of the present paper was to determine the impact of gypsum treatment of soils on initial growth and nutrient uptake by spring barley. Topsoil from 36 different farmed fields was used for the research. Two variants were established for each soil: control - without gypsum application, and response variant - with the application of 3.3 ppm CaSO₄.2 H₂O. Barley was grown on these soils for 21 days in a plant growth chamber under controlled conditions of cultivation. Concentrations of nutrients (N, NO₃^-, P, S, K, Mg, Ca, Na, Fe, Mn, Zn, Cu, B and Mo) were determined in the yield of barley shoot biomass. Paired t-test was used for the evaluation of results. After the gypsum treatment the yield of barley shoot biomass was significantly higher (by 15% on average) and nitrogen utilisation was better on all soils. The concentration of sulphur increased five times on average and Ca concentration increased by 22%. Significant increases were measured in Mg, Mn and Cu. Insignificant differences were recorded in K, Na, Fe and Zn. The uptake of anion nutrients (P, B and Mo) was influenced significantly. The concentration of P and Mo decreased on average by 28% and 31%, respectively. B concentration was higher by 10% on average.

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.

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

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

A six year old male iguana (Iguana iguana) was brought to our clinic after a fall from a height of 1.5 meters. The patient showed apathy, dehydration, and paresis of all the limbs. Postural reflexes, palpebral reflex, and response to painful stimuli were minimal. The patient had extremely high levels of uric acid (1 734.0 µmol/l) and phosphorus (9.80 mmol/l), ratio of calcium to phosphorus (0.18), leucocytosis (23.3×10⁹/l) with heterophilia (17.10×10⁹/l), and high activity of ALT, AST and CK (2.09, 6.59, and 260.0 µkat/l). Tracheoscopy and pneumoscopy revealed presence of blood clots in the trachea and lungs with haemorrhage within the parenchyma. Based on the results of the clinical examination, endoscopy and laboratory diagnostics, the clinical diagnosis was chronic kidney failure, liver lipidosis and lung haemorrhage. Because of a very poor prognosis, the patient was euthanised. At necropsy, the signs of visceral gout and hepatomegaly with diffuse yellowish white discoloration and with dotted brown pigmentation were also observed. The kidneys were enlarged, and stained brown grayish. The gross and histopathological examination confirmed the clinical diagnosis of visceral gout, chronic kidney failure, liver steatosis and granulomatous pneumonia, with lung haemorrhage associated with urate deposits in lung tissue and posttraumatic status.

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

This study had the aim of investigating the anatomy of the aortic arch in squirrels (Sciurus vulgaris). Ten squirrels were studied. The materials were carefully dissected and the arterial patterns of arteries originating from the aortic arch were examined. The brachiocephalic trunk and the left subclavian artery were detached from the aortic arch. The brachiocephalic trunk first gave the left common carotid artery, and then detached to the right subclavian and common carotid artery. In all the examined materials, the left and right subclavian arteries gave branches that were similar after leaving the thoracic cavity from the cranial thoracic entrance. But while the whole branches of the the right subclavian artery were arising from almost the same point the left subclavian artery gave these branches in a definite order, and the branches that separated were the following: the internal thoracic artery, the intercostal suprema artery, the ramus spinalis, the vertebral artery and the descending scapular artery. It also gave the common branch formed by the junction of three of the cervical superficial, the cevical profund and the suprascapular arteries. After the separation of these branches, continuation of the artery gave the external thoracic artery on the external face of the thoracic cavity and then formed the axillar artery. The axillary artery separated into the subscapular and the brachial arteries. Thus, the arteries originating from the aortic arch and the branches of these arteries are different from other rodents and from domestic mammals.

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

The use of plants to remove heavy metals from soil (phytoremediation) is expanding due to its cost-effectiveness as compared to conventional methods and it has revealed a great potential. Since contaminants such as Pb or Cd have a limited bioavailability in the soil, methods to facilitate their transport to the shoots and roots of plants are required for successful phytoremediation. The objective of this study was to investigate the effects of addition of different rates (0, 3, 6 and 12 mmol/kg) of ethylene diaminetetraacetate (EDTA) on heavy metal availability in soils contaminated with 50 mg/kg Cd (CdCl₂), 50 mg/kg Cu (CuSO₄), 50 mg/kg Pb [Pb(NO₃)₂] and 50 mg/kg Zn (ZnSO₄), and on the capacity of canola (Brassica napus L.) and Indian mustard (Brassica junceaL.) plants to uptake Cu, Cd, Pb and Zn in a growth chamber. Results indicated that EDTA application increased heavy metal availability and uptake by plants. Significant differences were obtained in both species and plant parts. As for plant species tested, canola was more effective in the uptake of Cu, Cd, Pb and Zn. Root heavy metal uptake of both species was higher than shoot heavy metal uptake.

This paper presents the results of a three-year research on the effect of perforated polyethylene foil and polypropylene fibre covering at various lengths of plant cover period (2 and 3 weeks after plant emergence) on the assimilation leaf area of early potato cultivars. In the case of plant covering for 2 weeks after emergence the assimilation leaf area and leaf area index (LAI) at the moment of cover removal were on average 2 times higher than in the cultivation without covering; at the 3-week period of plant covering they were almost 1.7 times higher. A higher favourable effect of covering was obtained in the year with the lowest air temperature in May. The use of the covers at that time increased the assimilation leaf area and LAI 2.5 times and 3 times, respectively. The research showed no significant effect of the type of cover used on the assimilation leaf area and LAI; however, the specific leaf area (SLA) was higher with the use of polypropylene fibre.

Chlorophyll a fluorescence measurements were carried out on two barley (Hordeum vulgare L.) cultivars Arabi Abiad and Arabi Aswad at 8 and 14 days after emergence to identify their early tolerance mechanism for heavy metals (25 and 50μM of cadmium and lead). Transient fluorescence curves (OJIP curves) and energy flux models showed different specific reactions of photosystem II (PSII) of each cultivar to each type of stress. After 7 days of lead stress application plants of cv. A. Aswad showed weaker I and P peaks on the OJIP curve than control plants, and the appearance of a new K step; parameters of phenomenological energy fluxes for cv. A. Abiad were similar to those for control plants and only some silent reaction centers appeared. Generally, parameters of energy fluxes within PSII were directly shifted shortly (24 h) after the application of both heavy metals, especially in the case of plants grown under cadmium treatment. This suggests that these parameters could be good indicators for monitoring of these two pollutants in the environment at early stages of plant development.

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