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Soils of reclaimed dumpsites after coal mining are considered as typical anthropogenic soils. These soils are at the beginning of their development and have certain specific characteristics. The aim of this study was to describe a soil survey performed on anthropogenic soils of a reclaimed dumpsite, to analyse spatial variability of selected properties using geostatistical methods, and to evaluate the development of reclaimed dumpsite soils. It has been shown that geostatistical methods are suitable for a description of anthropogenic soil properties and their variability. However, characterization of soil properties on the border between areas with different types of reclamation can be difficult due to sharp discontinual transitions caused by human activity. Properties of these soils vary profoundly greatly dependent on the properties of the soil substrate and the type of reclamation. The average content of organic carbon in the topsoil (0-20 cm) was 1.92% on the area covered with a layer of natural topsoil and 0.92% on the area covered by a layer of loess. An initial A horizon can develop even in 10 years under favourable conditions.

The article presents original results of research on the humus form dynamics in a semi-natural European beech stand in the National Natural Reserve Voděradské bučiny, in the area of Training Forest Enterprise at Kostelec nad Černými lesy (Czech University of Agriculture inPrague). The accumulation and soil chemical characteristics of particular humus forms were studied: dry matter amount, pH, soil adsorption and exchangeable acidity characteristics as well as plant available and total nutrient contents. The humus form samples were taken in four replications from the particular humus form layers (L, F, H, Ah), and the analyses were performed individually. Samplings were done in the parts of the stand with closed canopy, and they were compared with the state in gaps formed during natural and semi-natural forest regeneration (the stage of stand breaking up left to spontaneous development). The results confirmed marked changes in the quantity and quality of surface humus in the gaps. The amount of dry matter decreased by ca. 25% several years after canopy opening, especially in the H horizon, the pH, base content and base saturation increased, as well as the content of macronutrients (with the exception of total calcium). The results proved considerable changes in the humus forms during the natural and semi-natural forest cycles connected with the stand regeneration.

The effects of soil conditioners Frisol, TerraCottem, Bi-algeen, and fertilisers Silvamix Forte and Cererit on the welfare of Austrian pine were observed in a seven-year experiment on Loket spoil bank. Simultaneously the economic aspects of growing the Austrian pine until the stage of established plantation were examined. The application of products one year and a half after planting did not cause seedling mortality. The elongation growth of young plants conditioned by the application of Silvamix Forte and Frisol was statistically significant whereas these effects manifested themselves in the second year: they persisted till the end of the experiment for Silvamix Forte, and for three years in total for Frisol. The other products - TerraCottem, Bi-algeen and Cererit - also showed generally better, though statistically insignificant results as compared to those of the control plants. The elongation growth for all products culminated in the fifth year and then declined. The stem diameter growth for the best products reached its maximum in the second year. Regarding the overall height growth after seven years, the average number of the highest plants on the experiment location was on plots treated with Silvamix Forte; these plants exceeded the control plants by 46.2 cm. Pines treated with Frisol were higher by 23.4 cm. However, the application of soil conditioners and fertilisers to the given location proved economically ineffective because there was no need to improve the soil at the location, the same applies to mowing and hoeing since almost no forest weed grew there and the substrate surface remained well-aerated and porous.

This paper deals with the analysis of the trends in costs and revenues of selected agricultural products grown and bred under the conditions of organic agriculture. The analysis of the trends in revenues and costs is performed for the cattle breeding, beef cows and for the plant production of spelt, oat and potatoes. Costs are evaluated in the relationship with the direct and indirect costs. Revenues are traced with the help of per hectare yield, efficiency and market prices. Data of the selected file of the organically farming companies for the controlled commodities are compared with the same commodities of the selected file of the conventionally farming companies worked by the Research Institute of Agricultural Economics (RIAE) in Prague.

Perennial ryegrass (Lolium perenne L.) is the most important grass species used in temperate grassland agriculture. Our objective was to obtain an overview of the genetic relationships between 20 individual genotypes of perennial ryegrass of diverse origins, using amplified fragment length polymorphism (AFLP), inter-simple sequence repeat (ISSR), random amplified polymorphic DNA (RAPD) and two sets of simple sequence repeat (SSR) markers. All 20 individuals were uniquely fingerprinted by all four marker systems and comparisons were made on the basis of 85 markers each. Mean genetic similarities were estimated at 0.31, 0.43, 0.23 and 0.15 for AFLPs, ISSRs, RAPDs and SSRs, respectively. Cophenetic values resulted in good (AFLP and SSR-B = 0.88) to moderately good fits (ISSR = 0.76, RAPD = 0.70, and SSR-A = 0.79). Comparing the four marker systems to each other, AFLP and SSR-A were correlated best (r = 0.57). All other comparisons revealed rather low correlation coefficients in the Mantel Z test. With twice as many markers cophenetic values increased to a very good fit for AFLPs (0.90) and SSRs (0.92).

Cadmium mobility in sewage sludge amended by four types of ameliorative materials (lime, limestone, bentonite and zeolite) incubated under aerobic and anaerobic conditions for eight months was studied in the experiment. The most statistically significant decrease of available Cd extracted by 0.01 mol/l CaCl₂ was recorded in sludge between second and fourth months of incubation. As most effective stabilizers were found limestone and bentonite added into the sludge incubated under aerobic and anaerobic conditions respectively. The presence of air reduced Cd mobility in individual sludges more than lack of air. Cadmium was separated by sequential extraction into five fractions as water soluble, exchangeable, bound with Fe and Mn oxides, organically bound, and residual fraction. Sequential analysis showed decrease of Cd in exchangeable and oxide fractions in sludge treated by lime and limestone at the end of aerobic incubation. Cadmium was found in water soluble and exchangeable fractions in small portion, even so its content in these fractions was higher than determined in slighter 0.01 mol/l CaCl₂ solution.

In the years 1999-2003 the effect of covering rows of early potatoes with non-woven fleece on the yield formation, dry matter content in tubers, temperature of soil and of air in ground layer was investigated. Covering of rows enhanced the market yield of tubers at early harvest 60 days after planting in average by 35.8% in comparison with the uncovered control. At harvest 67 days after planting the difference in advantage of the covered variant were 17.2% and 85 days after planting the difference in yield between variants was already non significant. The yield effect of the fleece was affected by year (higher effect in the years with cold spring) and by variety (Impala responded at 60 days after planting by yield increase under fleece 43.7%, Adora 27.9%). Higher dry matter content of tubers by 0.87% was found in covered plants 60 days after planting in comparison with control. Cover enhanced average air temperature in ground layer by 2.0°C, in soil in depth 100 mm by 1.8°C.

The amelioration of aflatoxicosis in broiler chickens was examined by feeding two concentrations of yeast component (esterified glucomannan; EG). EG, incorporated into the diet at 0.5 and 1 g/kg, was evaluated for its ability to reduce the detrimental effects of 2 mg total aflatoxin (AF; 82.72% AFB₁, 5.50% AFB₂, 10.20% AFG₁ and 1.58% AFG₂) in diet on growing broiler chicks from 1 to 21 d of age. A total of 240 male broiler chicks (Ross-308) were divided into 6 treatment groups [control, AF, EG (0.5 g/kg), AF plus EG (0.5 g/kg), EG (1 g/kg), and AF plus EG (1 g/kg)]. Compared to the control, AF treatment significantly decreased body weight gain from week 2 onwards. AF treatment also caused significant decreases in serum total protein, albumin, total cholesterol, triglyceride, glucose, inorganic phosphorus, creatinine levels and alanine-aminotransferase (ALAT) activity but increased the aspartate-aminotransferase (ASAT) activity. Red blood cell, haematocrit, haemoglobin, thrombocyte, and lymphocyte counts and tibial crude ash levels were significantly reduced by AF treatment, while significant increases were seen in heterophil counts. The addition of EG (1 g/kg) to an AF-containing diet significantly improved the adverse effects of AF on haematological parameters, total protein, albumin values and ASAT activity. EG (1 g/kg) also partially improved body weight gains (59%) and the other biochemical parameters influenced by AF treatment. The addition of EG (both 0.5 and 1 g/kg) to the AF-free diet did not cause any considerable changes in the investigated values. These results clearly indicated that EG (1 g/kg) addition effectively diminished the adverse effects of AF on the investigated values. Also, the higher dietary concentration of EG (1 g/kg) was found more effective than the lower concentration (0.5 g/kg) against the adverse effects of AF on the variables investigated in this study.

The effect of partial and total replacement of soybean meal (SBM) with extruded chickpeas (Cicer arietinum L.) and partial replacement of SBM with raw chickpeas on pig growth and carcass characteristics was determined in a 17 week experiment. Sixty growing-finishing pigs were allocated to five dietary treatments: CKP0, ECKP100, ECKP200, ECKP300 and CKP100 of 12 animals each, and received a diet ad libitum. The diet for CKP0 treatment had no chickpeas (control), while those for treatments ECKP100, ECKP200 and ECKP300 included 100, 200 and 300 kg/t of extruded (at 120°C for 20 s) chickpeas, respectively, and for treatment CKP100 it included 100 kg/t of raw chickpeas. Body weight (BW) gain linearly increased (P < 0.05) and feed conversion ratio (FCR) linearly decreased (P < 0.05) with the inclusion of increasing levels of extruded chickpeas during the growing period. However, in both the growing and finishing period, there were no differences between extruded chickpea inclusion treatments in final BW, BW gain, daily feed consumption (DFC), FCR, and carcass yield traits. Partial replacement of SBM with raw chickpeas negatively affected (P < 0.05) BW gain and DFC during the finishing period. Extrusion offers a practical method for the heat processing of chickpeas for use in pig diets. Thus, extruded chickpeas can be used as an alternative protein source to SBM at inclusion levels up to 300 kg/t of diet.

Haemophilus parasuis is a common epiphyte of the upper respiratory tract of pigs. The factors of H. parasuis pathogenicity that enable some strains to be virulent and consequently cause a clinical disease have not been established yet. Fifteen serovars of H. parasuis have been described at present. Individual serovars differ in virulence, and considerable differences in virulence also exist within each serovar. Virulent strains can particularly participate as microorganisms secondary to pneumonia, cause septicaemia without polyserositis or Glässer's disease characterized by polyserositis, pericarditis, arthritis and meningitis. Clinical symptoms of this disease are highly variable. Therefore, culture detection of causative agent, particularly from the brain, joints and polyserositis is an essential diagnostic tool. The disease caused by H. parasuis can be treated with antibiotics; however, oral or parenteral administration of very high doses of antibiotics is necessary. The level of animal hygiene and animal husbandry are important factors for prevention of this disease. Commercial or autogenous vaccines can be used in the immunoprophylaxis of pre-parturient sows and their progeny after weaning. For the production of autogenous vaccines, it is most effective to use isolates from animals with lesions present in CNS. Isolates recovered from arthritic and systemic sites of infection are less suitable and isolates recovered from lungs are not suitable at all because of their heterogeneity.

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

Forests have been subject to human intervention since the inception of human civilization. With enhanced knowledge, understanding and capacity humans exert an increasing pressure and influence on forests. Forests in general have undergone different ownership patterns. The requirements for forests have changed over time. The objectives of forest management are shifting from timber production to biodiversity conservation and nature protection. On the other hand, in many places the forests are dwindling due to the anthropic pressure. The management paradigms are changing in response to these triggering mechanisms. In this paper an attempt has been made to summarize the evolution of forest management practices and discuss some recent trends in forest management.

The second part of the paper summarizes results of an institutional research aimed at the determination of physical and mechanical properties of different sets of plywood sheets pressed under different conditions. The first part dealt with the determination of compressibility or values of decreasing the thickness of pressed plywood sheets. In this second part, results are summarized of the analysis of physical and mechanical properties of the set of whole-beech plywood sheets of the nominal thickness of veneers amounting to 1.5 mm. The plywood sheets were manufactured as seven-ply and urea-formaldehyde resin DUKOL S was used for their production. The sheets were pressed using a pressure of 1.5 and 1.7 MPa. Following parameters were analyzed: moisture, density, bending strength, MOE in bending and shear strength.

Norway spruce yellowing and defoliation caused by Mg deficiency was frequently recorded on many sites of the Šumava Mts. (Bohemian Forest Mts.) since 1980's. A forest experiment aimed at investigation response of spruce to Mg application (commercial fertilizer SILVAMIX^® Mg NPK) was set up in 1998. Fertilizer was applied manually in a dose of 96.5 kg Mg/ha in spruce (S) and beech-spruce (BS) vegetation altitudinal zones in spring 2000. Immediate decrease of yellowing was revealed in fertilized plots in both vegetation zones and yellowing almost completely disappeared at the end of the investigation in 2005. Further, fertilization resulted in stabile foliation while marked defoliation was reported from control plots in both vegetation zones. Mg deficiency can be effectively eliminated by appropriate fertilizer application. Balanced nutrition contributes to long-term vigour and stability of forest stands.

The conception of the agricultural politicy of the Czech Republic is in accordance with the European model of agriculture, and one of this politicy pillars has been concentrated on the development of the multifunctional agriculture. In this contribution, several findings from the solution of the research project QF 4142 have been summarised in a synthetic form. It introduced financing and support programme of the rape methyl-esther (RME) and mixed fuel production. In the article, the availability and economic potential of the renewable energy sources till the year 2010 are shown primarily. The RME and the bio-diesel form an important part of the biomass in the Czech Republic. We describe in brief the RME characteristics in the year 1997-2004 in the following fields: production and support of the RME and mixed fuel. We have the capacity of the RME production 150 000 t in the Czech Republic with the average costs 20 CZK/l RME.

Molecular and immunological methods were applied for detecting the Ganoderma disease of coconut. Polyclonal antibodies (PAbs) raised against basidiocarp protein of Ganoderma were used. For the polymerase chain reaction (PCR) tests, the primer generated from the internal transcribed spacer region one (ITS 1) of ribosomal DNA gene of Ganoderma, which produced a PCR product of 167 bp in size, was used. Apparently healthy palms in two coconut gardens were tested for Ganoderma disease by ELISA test using basidiocarp protein antiserum. Field trials were laid out in these early-diagnosed palms for the management of the disease. Based on the ELISA results, Pseudomonas fluorescens + Trichoderma viride with chitin amended treatments arrested the multiplication of the pathogen and within 6 months showed an optical density (OD) below the level of infected plants. Integrated Disease Management (IDM) and fungicide tridemorph treated palms showed OD values below infection level within 7 months, and T. harzianum and P. fluorescens + T. viride treated palms showed OD values below infection level in 8 months.

Soil organic carbon (SOC) is the most often reported attribute and is chosen as the most important indicator of soil quality and agricultural sustainability. In this review, we summarized how cultivation, crop rotation, residue and tillage management, fertilization and monoculture affect soil quality, soil organic matter (SOM) and carbon transformation. The results confirm that SOM is not only a source of carbon but also a sink for carbon sequestration. Cultivation and tillage can reduce soil SOC content and lead to soil deterioration. Tillage practices have a major effect on distribution of C and N, and the rates of organic matter decomposition and N mineralization. Proper adoption of crop rotation can increase or maintain the quantity and quality of soil organic matter, and improve soil chemical and physical properties. Adequate application of fertilizers combined with farmyard manure could increase soil nutrients, and SOC content. Manure or crop residue alone may not be adequate to maintain SOC levels. Crop types influence SOC and soil function in continuous monoculture systems. SOC can be best preserved by rotation with reduced tillage frequency and with additions of chemical fertilizers and manure. Knowledge and assessment of changes (positive or negative) in SOC status with time is still needed to evaluate the impact of different management practices.

The objective of the study was to quantify differences in the carcass composition of pig carcasses with different lean meat proportions. Totally 132 carcasses with lean meat proportions ranging from 45 to 65% were analysed. The average lean meat proportion in the analysed set of carcasses was 55.38% (s = 4.319). The carcasses were classified into the groups according to their lean meat proportion (R, 45.0 to 49.9%; U, 50.0 to 54.9%; E, 55.0 to 59.9%; S, more than 60.0%). Carcasses from each group were cut into primal cuts and the main cuts (leg, loin, shoulder and belly with bones) were further separated into different tissues. Carcass value was markedly enhanced by the increasing carcass lean meat proportion. Average leg percentages in the groups R, U, E and S were 17.88% (s = 0.918), 19.32% (s = 0.889), 20.88% (s = 0.817) and 21.88% (s = 0.827), respectively. Average proportions of fat over leg expressed as percentages of leg weight in these groups were 5.82% (s = 0.402), 4.87% (s = 0.556), 4.05% (s = 0.479) and 3.21% (s = 0.321), respectively. Lean meat proportions of leg weight were improved from 84.93% (s = 1.136) in the group R to 88.12% (s = 0.986) in the group S. The most distinct differences were found in lean proportions of belly weight. The observed averages in the group R and S were 43.90% (s = 2.729) and 62.10% (s = 2.219), respectively. Actually, in carcasses with a high classification score the belly can be considered as a cut with the predominant muscle tissue. The results of the study proved the efficiency of carcass evaluation based on the lean meat proportion. Such a method can significantly contribute to the overall improvement of pig production.

The production of adult steers for beef could be a profitable use of the territory in some mountain areas in the south of Europe, where this production is nearly inexistent, owing to an increase in the demand for meat from adult animals in specialized markets. The objective of this study was to evaluate the profitability of beef production in three breeds adapted to these areas but varying greatly in their mature size. The studied breeds were a specialized meat breed Limousin, a dual-purpose breed - Brown Swiss breed and - a Spanish local breed Asturiana de los Valles. Higher growth rates (P < 0.05) and higher carcass weights (P < 0.05) were achieved by Brown Swiss and Limousin. In relation to carcass value, better results of dressing percentage (P < 0.001), conformation (P < 0.001) and saleable meat percentages (P < 0.001) were obtained byLimousin. Due to preferences of the adult steers market for carcass with high fatness, Brown Swiss and Limousin could be more suitable to make this production profitable than Asturiana de los Valles (4.7 and 4.2 vs. 2.7, respectively, on the EUROP scale).

Nitrite is an intermediate in the oxidation of ammonium to nitrate. An elevated ambient nitrite concentration is a potential problem for freshwater fish since nitrite is actively taken up across the gills in competition with chloride. Nitrite is a well-known toxicant for fish as well as a disrupter of multiple physiological functions including ion regulatory, respiratory, cardiovascular, endocrine and excretory processes. One critical consequence of nitrite accumulation is the oxidation of haemoglobin to methaemoglobin, compromising blood oxygen transport. Nitrite toxicity to fish varies considerably and depends on a large number of external and internal factors. Among the most important ones are water quality (e.g. pH, temperature, cation, anion and oxygen concentration), length of exposure, fish species, fish size and age, and individual fish susceptibility. Chloride concentration in water is considered one of the most important factors influencing nitrite toxicity to fish. The importance of individual factors is assessed and re-evaluated continuously.

Mononuclear cells from rabbit bone marrow were cultured for 14 days in cell-free medium for hematopoietic cells together with iron oxid nanoparticles, and then they were processed by technique for free cells for TEM (transmission electron microscopy). Staining with turnbull blue was used for the detection of iron using a light microscope. It was shown that iron nanoparticles were incorporated into the cytoplasm of mononuclear cells during 14 days cultivation. Here they were localized within different sized vacuoles with distinct membranes.

Putting together work operations minimizes the number of machine passes across the plot, which helps to reduce negative soil compaction and to save fuels. However, the combination of working operations also reflects in the increased weight of machines, which - on the other hand - can result exactly in soil compaction. This is why the potential adverse phenomenon can be compensated by using tyres with a larger contact surface with the base. In the case of sowing root crops, some problems may appear with the application of these tyres as a certain part of the stand has been sown in their track. The paper brings an assessment of the possibility to use twin assembly tyres on the tractor model Fendt 822 and on the sowing drill model Monosem NG plus with 18 drilling mechanisms. Parameters to be assessed were soil compaction, and the development of plants sown inside and outside the tractor track. Although the degree of soil compaction was higher in the tractor track, the biological characteristic of plants including yield reached more favourable criteria of assessment. The situation paradoxically resulted from the creation of more favourable moisture conditions in the soil.

In the course of a 3-year study the natural occurrence of storage diseases in ambient air storage with 1 to 2°C was evaluated on samples of 30 cultivars and advanced selections that were harvested from orchards with and without the use of fungicide treatments. Based upon the frequency of occurrence, bitter rot and grey mould were the most common diseases in this study followed by blue mould and brown rot. Fungicide treatments applied in the orchard with integrated plant protection reduced total fruit rotting with different cultivars two to four times. Significant losses caused by rotting usually took place in the last quarter of the normal storage life of each cultivar, but in the case of samples treated with fungicides it was mostly during the last month. Cultivars Angold, Gala, Florina, Melodie and Meteor proved to be partially resistant to the storage diseases, but the smallest shares of rotted fruits were recorded on apples of Zuzana andMelrose. Still, five advanced selections proved not to be so affected by fruit rotting asMelrose and Zuzana, from which HL 237 and HL 390 were the most remarkable. The majority of selections with resistance to storage diseases as well as Zuzana cv. contain Glockenapfel cv. in their pedigree.

Frost cracks which originated in birch due to bending during long-term icing in winter 1995/1996 became the place of entrance for the attack of birch stems by Piptoporus betulinus (Bull. ex Fr.) Karst. and subsequently for one of the causes of birch stand disintegration in the Krušné hory Mts. The hypothesis is substantiated on the basis of regularities of the frost crack dispersion in the stem profile, frequency of occurrence related to the stand age, altitude and cardinal points. The number of frost cracks increased with the transect profile altitude 700-850 m. One crack on the birch stem predominated (73%) while the higher number of frost cracks occurred at altitudes > 800 m. In stands younger than 20 years, frost crack damage was higher (34-47%) than in older stands (14%). Frost cracks occurred in the lower part of stems with the highest bending stress.

At the end of nineties, within the mountain forests of the Krušné hory Mts., in connection with an increased acid deposition, the symptoms (yellowing) started to be visible, characterizing magnesium deficiency in the assimilation organs, when Mg contents were laying under 300 mg/kg. In mineral soil the Mg content is mostly less than 10 mg/kg. Contents of other basic elements (Ca, K) were also very low. During four years yellowing symptoms of the spruce stands have developed in an extent area of more that 10,000 ha. Since 1999, preventive measures have been adopted to improve the nutrition status of the forest stands. Liquid magnesium fertilizers as MgNsol, Lamag Mg, MgSsol were applied during the period of 1999-2002. Since 2001, in semi-operational experiment, powder Mg fertilizer - Silvamix F4 - of higher Mg content (63.3% MgO) was applied. Application of liquid fertilizer MgNsol has helped to compensate the nitrogen deficiency in the stands of insufficient nutrition in this element. Comparing of different types of liquid fertilizers has confirmed, that the highest increase of magnesium in assimilation organs was find in combined application of MgNsol and MgSsol fertilizers. Application of 300 kg/ha Silvamix F4 has increased the magnesium content in the first needle year class in 73% in average, potassium in 33%, calcium in 16%, and phosphorus in 85%. Besides increased nutrient content in needles also improvement of the health and phosphorus in 85%. Besides increased nutrient content in needles also improvement of the health state, i.e. revitalization of the stands affected can be observed.

The article summarizes recent developments in the field of knowledge management and its vital influence on strategic management. Knowledge has become a resource of key importance with regard to the competitive advantage of a business. It thus strengthens the resource-based view of competitive advantage and develops it further by providing guidelines for developing, storing, and sharing knowledge within a business with the use of the concept of organisational learning. Tacit and explicit knowledge is distinguished in order to differentiate their contribution towards the competitiveness of a business. Based on these developments major trends affecting current development of strategic management are defined as well as recommendations drawn from the experience of leading subjects in the field.

Limited information is available regarding the source-sink alterations on soybean yield under whole plant light enriched conditions. The differential responses of yield components for two old and two new cultivars were investigated. The yield sensitivity of the old cultivars to the changes in source strength and light enriched conditions was much greater than that of the two new cultivars. The yield of the new cultivars was more likely sink-limited, and source-limited for the old cultivars. The increased yield by light enrichment was in part due to an increased branch contribution. Pod number per plant was more responsive than seed number per pod. The reduction in pod number by source-sink manipulation was more severe in the old cultivars. Light enrichment increased pod number in the two old cultivars but not in the two new cultivars. Seed size was responsive to changes in the source-sink ratio and changes in the environment. Both pod number or seed size may be increased or decreased if environmental conditions for seed filling are altered.

The aim of this study was to investigate an association between aggressiveness and high level of feeding in a half-open feedlot production system. An experiment was conducted on 72 head of beef cattle of different breeds. The animals were at about 10 months of age. Medium quality silage was offered ad libitum and supplemented with high (HE) and low level (LE) of barley (2.5 and 1.5 kg/day/head, respectively) and supplemented without (nil) or with (+) extracted soybean meal (0.45 kg/day/head). Several types of animal behaviour were observed such as those parameters that are categorized to be main aggressive behaviours, butting, being butted, mounting and being mounted. Significant differences (P < 0.05) were found in butting, being butted behaviours between HE and LE treatment groups. Mounting and being mounted behaviours were significantly different (P < 0.05) in steers and heifers and between the seasons as well. Steers performed more incidents of mounting behaviour than heifers and it was the same for spring, during which animals had more mounting behaviours. It was concluded that there was a close relationship between high-energy diets and aggressive behaviour, which necessitates some management measures to be taken in order to ensure better animal welfare and beef production.