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The influence of accelerated ageing test (AAT), i.e. of higher temperature and humidity, on the content and composition of phenolic compounds in the grains of five cultivars of wheat (Triticum aestivum L.) was studied in the years 1998 and 1999. Total polyphenols were determined spectrophotometrically by Folin-Ciocalteau's phenolic reagent and free phenolic acids by an HPLC method in control samples and after deterioration treatment (AAT) in the Ebi, Estica, Nela, Samanta and Šárka cultivars. Statistical significance of deterioration treatment, cultivar, cultivation site, and harvest year was proved. Content of total polyphenols increased during deterioration and levels of the individual free phenolic acid changed depending on their structures. Mean contents of total polyphenols varied from 600 to 960 mg/kg of dry matter. The increase caused by the AAT ranged between 0-20%, the greatest mean increase was observed in the cultivar Nela (by 19%). Sinapic acid (as high as 540 mg/kg of dry matter), 3-hydroxy-benzoic acid and 7-hydroxycoumarin were determined as the major phenolic acids and coumarins. A decrease of free phenolic acids containing methoxy groups in their molecules (sinapic and vanillic acids) and an increase of phenolic acids with free hydroxy groups (caffeic and gallic acids) was observed after deterioration treatment. Statistically significant (P ≤ 0.05) effect of AAT on the content of free phenolic acids was observed.

Field experiments were carried out to study effects of zinc application on quality traits of barley in 1994-1996. The treatments were applied as 0 and 23 kg/ha of zinc sulphate and incorporated into soil before sowing. The experimental design was split plot with four replications. Barley genotypes responded differently to zinc application in relation to thousand grains weight, protein content and starch content. A significant increase was determined for thousand grain weight in cultivars Tokak 157/37 and Cumhuriyet 50, for protein content in Orza, Bülbül 89 and Anadolu 86, for starch content in Karatay 94 and Cumhuriyet 50, while a significant decrease has been found for thousand grain weight in Karatay 94 and Obruk 86 and for protein content in Karatay 94, Cumhuriyet 50 and Tarm 92. When feeding and malting quality are considered together, Karatay 94 and Cumhuriyet 50 are the most suitable cultivars for growing in zinc-applied soils of semi arid areas.

The present investigation was conducted to know the impact of bio-inoculants in low input field conditions on the magnitude and direction of gene effects and mean performance of some morphological and productivity traits in three wheat cultivars WH 147 (medium mineral input), WH 533 (drought tolerant), Raj 3077 (drought tolerant) and six generations namely P₁, P₂, F₁, F₂, BC₁ and BC₂ of three crosses i.e. WH 147 × WH 533, WH 533 × Raj 3077 and WH 147 × Raj 3077. The experiment was conducted in randomised block design with three replications and three treatments i.e. control (C, without inoculation), inoculation with arbuscular mycorrhiza fungi (AMF, Glomus fasciculatum), and AMF + Azotobacter chroococcum (Azc). Mineral fertilizer (80 kg N/ha + 40 kg P/ha + 18 kg ZnSO₄/ha) was applied in all the three treatments. The application of bio-inoculants, AMF and AMF + Azc had a positive effect on plant height, peduncle length, grain yield, biological yield and harvest index in various populations of all the crosses. However, in some of the generations the impact of bio-inoculants was insignificant. The joint scaling test revealed that additive-dominance gene effects were mainly operative in governing expression of peduncle length, tillers per plant, plant height, grains/spike, grain yield and all traits except days to flowering and harvest index in crosses WH 147 × WH 533 and WH 533 × Raj 3077. The application of bioinoculants influenced gene effects for days to flowering, days to maturity, flag leaf area, spike length, grains/spike, 1000 grain weight and harvest index where complex genetic interactions were changed to simple additive-dominance gene effects in the cross WH 147 × Raj 3077. Likewise, additive-dominance gene effects were altered and digenic interactions exhibited for days to maturity, flag leaf area in WH 147 × WH 533 and days to flowering, plant height, flag leaf area in WH 533 × Raj 3077. Flag leaf area and plant height were governed by additive gene effects while for days to maturity and 1000-grain weight both additive and dominance gene effect were important. Duplicate epistasis was important in all the three crosses for days to flowering and harvest index and in the cross WH 147 × Raj 3077 for grain weight grains per spike and flag leaf area.

Analysis of spatial distribution and correlation of soil properties represents an important outset for precision agriculture. This paper presents an analysis of spatial distribution and mutual correlations, both classical and spatial, of soil properties in an agricultural field in Klučov. Clay and fine silt content, pH, organic carbon content (C_org), moisture (Q), total porosity (Pt), capillary porosity (P_c), and coefficients of aggregate vulnerability to fast wetting (K_v1), to slow wetting and drying (K_v2), and to mechanical impacts (K_v3) were determined. Semivariogram ranges from 206 m (clay content) to 1120 m (K_v3) were detected. Many relationships between soil properties were spatially based. Fine silt content and Corg proved to be the most important soil properties controlling all the three aggregate vulnerability coefficients, which was not clear for K_v2 from classical correlation only. Determined spatial correlations and similarities in spatial distribution may serve as groundwork in delineation of different zones for site-specific management.

In the present paper genetic relationships of twenty varieties of cashew are described on the basis of morphological characters and RAPD (Randomly Amplified Polymorphic DNA) markers. Results obtained for the phenotypic characters based on similarity coefficient were divided into four clusters with 70% similarity. By means of similarity coefficients (SG), cluster I was found to consist of twelve varieties. Cluster II consisted of a single variety, NRCC-1, cluster III consisted of six varieties and cluster IV had only one variety, Vridhachalam-2. The analysis started by using RAPD markers that allowed us to distinguish 20 varieties. A total of 80 distinct DNA fragments ranging from 0.2 to 3.0 kb were amplified by using 11 selected random 10-mer primers. Genetic similarity analysis was conducted for the presence or absence of bands in the RAPD profile. Cluster analysis clearly showed that 20 varieties of cashew grouped into two major clusters based on similarity indices. The first major cluster comprised one minor cluster. The other major cluster was divided into two sub-minor clusters, one sub-minor cluster having three varieties and the other sub-minor cluster was represented by 15 varieties. Among the 20 varieties, Ullal-3 and Dhana (H-1608) showed the highest similarity indices (87%). It was noted that Vengurla-2 and Vengurla-3 were not grouped into a single cluster but Vengurla-4 has 82% similarity to Vengurla-3. The variety Vengurla-2 has very close similarity (85%) with variety Vridhachalam-3 (M-26/2). The analysis of genetic relationships in cashew using morphological traits and RAPD banding data can be useful for plant improvement, descriptions of new varieties and also for assessment of variety purity in plant certification programmes.

High yielding varieties of rice (Oryza sativa) cultivars were tested for their tolerance to different levels of molybdenum (Mo) (0.1µM - control, 0.2, 0.4, 0.8 and 1.6µM) in nutrient solution at pH 6.8. Seeds of rice were germinated and grown in presence of molybdenum under controlled environmental conditions. Standard growth parameters such as root length, shoot length, root/shoot dry biomass and root/shoot tolerance index were tested as markers of molybdenum toxicity. Measurements as early as 48 hours after the germination did not yield consistent results. However, root measurement on 3^rd, 6^th and 9^th day after root emergence showed significant differences among cultivars of rice. Rice cultivars Annapurna, Kusuma, Deepa and Vaghari developed better root system while, Paridhan-1, Pusa-2-21 and Ratna showed poor growth of the roots in presence (0.8µM) of molybdenum. The root tolerance index (RTI) and the shoot tolerance index (STI) in Annapurna, Kusuma and Deepa in rice were high indicating their tolerance to molybdenum; Paridhan-1 and Ratna, however, showed low RTI and STI. Based on the growth parameters, twenty cultivars of rice were ranked in respect of their tolerance to molybdenum: Annapurrna > Deepa > Kusuma > Vaghari > Hamsa > Vikram > Bharati > Paridhan-2 > Aswathi > Subhadra > Sankar > Sakti > Nilgiri > Rudra > Hema > Pragati > Pusa-2-21 > Ratna > Paridhan-1, respectively. Molybdenum toxicity was correlated with increased peroxidase and catalase activity in different cultivars of rice. This method can be employed for quick screening of rice cultivars for molybdenum tolerance in breeding programmes.

As, Cd, Pb and Zn accumulation in the aboveground biomass of seven clones of Salix spp. and changes in element uptake by plants after element addition to soil were studied in a pot experiment. Unpolluted Chernozem (Suchdol) as a control and soils with addition of As (100 mg/kg), Cd (40 mg/kg) and either Pb (2000 mg/kg) (Suchdol-Pb) or Zn (2000 mg/kg) (Suchdol-Zn) were used for the experiment. Significant differences were found in the accumulation of elements between willow clones and also between different element additions to the soil. Although As and Cd uptake slightly increased in Suchdol-Zn soil compared to Suchdol-Pb soil, the element removal from soil was significantly higher in Suchdol-Pb soil due to a significant reduction of aboveground biomass yield in Suchdol-Zn soil caused by Zn phytotoxicity. The yield reduction decreased the uptake of plant-available elements by biomass, thus higher plant-available portions of As and Cd were found in Suchdol-Zn soil. Element removal from soil was more dependent on element contents in willow tissues in Suchdol-Pb soil than in Suchdol-Zn soil, where willow plants exhibited physiological symptoms of phytotoxicity.

The Cd and Zn accumulation and phytoextraction potential of seven willow clones was investigated in a pot experiment for two vegetation periods. Heavily polluted Fluvisol-Litavka, moderately contaminated Cambisol-Pribram, and unpolluted control Chernozem-Suchdol were used. Significant differences were found in Cd and Zn accumulation between the willow clones. Cd and Zn were transferred from roots to aboveground tissues and all tested clones confirmed higher Cd and Zn accumulation in leaves than in twigs. Cd and Zn amounts removed by willow leaves were the highest from the most polluted soil (up to 83% Cd and 71% Zn of total removal). Therefore the harvest of leaves is necessary if willows are planted for heavy metal phytoextraction. Although the extremely high Zn contamination of Fluvisol-Litavka significantly reduced biomass production, willows planted in this soil showed the highest Zn removal because of extremely high Zn accumulation (max. 5061 ppm in leaves). Clones planted in moderately contaminated soil achieved the highest Cd removal. Clones showed different abilities to remove Cd and Zn, which was dependent on soil type and contamination level. Remediation factors were determined less than 1% for Zn in the heavily polluted soil and also unsatisfactory for Cd. However, it was shown that willows were suitable phytoextractors of moderately contaminated soil. About 20% of Cd and 4% of Zn were removed by harvested biomass from the total content of soil after two vegetation periods.

Pea (Pisum sativum L.), sunflower (Helianthus annuus L.) and maize (Zea mays L.) plants were cultivated for 10 days in hydroponics at 1mM and 7mM nitrate or ammonium concentrations at regulated pH 6 and ambient CO2 level. Plant growth, content of total N and both ions in plant tissues, uptake of water and both N ions were evaluated, N uptake related to transpiration mass flow and to diffusion supply was calculated. Pea and sunflower preferred nitrate nutrition while maize plants used both N ions. The content of total N as well as of both N ions in plant tissues increased with N level with some exceptions. The uptake of both N ions related to transpiration mass flow was dependent on transpiration rate and N ion concentration. At a 1mM N concentration the uptake of N ions related to transpiration mass flow was low and reached in maize up to 16 times, in sunflower 11 times and in pea 2-3 times lower values in comparison with diffusion supply. At a 7mM N concentration N uptake in pea plants was totally supplied by transpiration mass flow, in sunflower plants the ratio of N supply related to transpiration mass flow amounted to 50% and in maize plants N supply through diffusion prevailed, amounting to 70-80%. These results explicate N starvation at low N supply that can intensify at elevated CO2 causing decreased stomatal diffusion.

A morphometric study of Amaranthus cruentus, A. retroflexus and their hybrid, A. × turicensis based on 75 plant samples (750 inflorescences), collected throughout the Olomouc-Holice area (Czech Republic), is presented. Using multivariete methods (including cluster analysis and canonical discriminant analysis), the existence of three groupings of plants was proven. The hybrid exhibited intermediate values of the width and length of female tepals, length of awl-shaped bracts, and seed size when compared with parental species. A germination experiment showed that dark seeds of A. × turicensis as well as dark seeds of A. retroflexus germinate scarcely and independently on the day length while light seeds of A. cruentus germinate promptly and markedly better under a short day regime. The chromosome analysis showed that A. retroflexus, A. cruentus, and A. × turicensis have the same chromosome number 34.

In the experiment conducted in the greenhouse, the different doses of UV-B radiation applied to the two species Avena fatua and Setaria viridis induced changes in leaf and plant morphology. It was a decrease of plant height, fresh mass of leaves, shoots and roots as well as leaf area. Besides, it caused the leaf curling in both of the species. The significant differences between Avena fatua and Setaria viridis in the studied traits were mainly due to the tillering ability of the species. The content of chlorophyll varied considerably. The average values of leaf greenness (SPAD units) for oats were about 43 while for green foxtail 32, respectively. U-VB did not reduce leaf weight ratio, shoot dry matter, shoot to root ratio and leaf area ratio.

N fertilization has a substantial influence on sunflower (Helianthus annuus L.) seed yield and quality. It was also well established that high-yielding sunflower hybrids had more N requirement than old cultivars such as open-pollinated ones. However, in Turkey, no sufficient information regarding the response of new developed oilseed sunflower hybrids to nitrogen fertilization under irrigated conditions. Therefore, a 2-year study was conducted to determine the effects of nitrogen application rates on the growth, yield, and yield components of two oilseed sunflower hybrids (AS-508 and Super 25) under irrigated conditions. In this study, all plant parameters were significantly influenced by applied nitrogen fertilizer rates. Yield response to nitrogen rates was positive and linear. Our research data indicated that under irrigated conditions N rate of 120 kg/ha was adequate for sunflower production in this region.

The effect of phenylurea with reported cytokinin-like activities on seed germination, seedling growth, activities of antioxidant enzymes, polyphenol, peroxidase, indoleacetic acid oxidase, and total phenolic compounds, flavonoids was investigated in stressed barley seedlings. The application of phenylurea decreases the activity of peroxidase, indoleacetic acid oxidase and increases the activity of polyphenol oxidase with decrease in total phenolic compounds and flavonoids and consequent increase in growth rate. Saline (NaCl) stress in barley seedlings causes an increase in total phenolic compounds, flavonoids and enhancement of peroxidase and indoleacetic acid oxidase activities and consequent decrease in growth rate. The adverse effect of salt stress on germination, antioxidant enzymes, phenolic compounds, flavonoids can partially be rectified by phenylurea.

The effect of Al stress on peroxidase activity and peroxidase isozymes was studied in roots of two barley cultivars with contrasting sensitivity to Al. Al treatment induced a tremendous enhancement of guaiacol peroxidase activity especially in roots of Al-sensitive barley cv. Alfor. After 48 h of Al treatment activity of peroxidase in roots of cv. Alfor was up to 5.5 times higher than the control roots. In contrast, activity of peroxidase in the roots of Al-resistant cv. Bavaria was about one half than that in roots of Al-sensitive Alfor. SDS-PAGE analysis revealed that at least five peroxidase isozymes are activated by Al treatment. Using IEF we determined that three of Al-induced peroxidase isozymes are cationic with pI about 8.2, 8.4 and 8.6, while two other are anionic isoperoxidases with pI about 4.0 and 4.5. Al induced increase in the activity of root peroxidases correlated with the extent of Al induced root growth inhibition. The inhibition of root growth in Al-sensitive Alfor represented 44% but in Al-resistant Bavaria only 21% in comparison with control plants. Higher peroxidase activity, as well, as higher inhibition of root growth in Al-sensitive Alfor suggest that enhanced oxidative stress generated by Al treatment is significantly more stressful in Alfor than in the Al-resistant Bavaria.

The influence of an interrupted K fertilisation on different K fractions of the soil, yield formation and K uptake by different crops was investigated in a long-term field experiment on Luvisol derived from loess. Irrespective of the previous K fertilisation, the interruption of K fertilisation resulted in a sharp decline of CAL extractable K. K concentration in the saturation extract as well as HCl extractable K were reduced while K fixation capacity increased within 10 years after omitting K. Omitting K fertilisation decreased yields of sugar beet and potatoes while cereals were not affected, although K uptake of all crops reacted to the differentiated K supply to a different extent.

Rapeseed (Brassica napus L.) is an important alternate oilseed crop in eastern Anatolia, Turkey. No information on plant density for rapeseed is available in this region. Therefore a study was initiated to investigate the effects of spacings between rows and spacings within rows on the yield and agronomic characteristics of two genotypes of spring rapeseed (Tower and Lirawell) in Erzurum, eastern Anatolia, during 1994 and 1995. The effects of spacings between or within rows on the yield and yield components of Tower and Lirawell, two cultivars of Brassica napus L., were studied for 2 years inErzurum,Turkey. Rows were spaced at 15, 30 and45 cm. Spacings within rows were 5, 10 and15 cm. The results of this study suggested that seed yield was significantly affected by spacings between rows but not by spacings within rows, and that rape yields were higher at the narrow (15 cm) row spacing compared to the middle (30 cm) and wider (45 cm) spacings.

Long-term field experiments conducted under different soil and climate conditions and their databases provide invaluable information and are indispensable means in the study of the productivity and sustainability of the soil management systems. We evaluated the results of the dry matter yields of the main products obtained with four variants of organic and mineral fertilisation in three long-term field experiments established in 1955. The experiments differed in the cultivated crops. The period of evaluation was 12 and 16 years (1985-2000), respectively. The productivity of nine-year crop rotation was lower with the fertilised variants than that with the alternative growing of spring wheat and sugar beets. The dry matter yields on the Nil variants, however, were higher in the crop rotation than in the alternate sugar beet and spring wheat growing, apparently due to the symbiotic nitrogen fixation. The dry matter yields of sugar beet and mainly of spring wheat declined in almost all variants of fertilisation in the alternate sugar beet and spring wheat growing, over the evaluated time period. In spite of the relatively high dry matter production, the declining yields indicated a lower sustainability of the alternate cropping system. Both organic and mineral fertilisation increased the production of the cultivated crops. The differences in the average dry matter yields were statistically significant. Both organic and mineral fertilisation enhanced significantly the N-uptake by the cultivated crops. The effectivity of nitrogen input was the highest with the alternate cropping of sugar beet and spring wheat indicating that it was more demanding for the external N-input and thus less sustainable than nine-year crop rotation.

Present study focuses on making best possible use of male gametophytic generation in carnation breeding program. Exploration of pollen population revealed the existence of variability in terms of pollen morphology and histochemical content among as well as within varieties and species of Dianthus caryophyllus and D. chinensis sufficient to make selection. Pollen grain size and histochemical content were found to be associated with germination capacity and pollen tube growth rate. In addition, pollen germination capacity and elongation of pollen tube in response to presence of culture filtrate from F. oxysporum. f.sp. dianthi causal organism of fusarium wilt in carnation was found to be governed by pollen grain size and histochemical content of pollen grains. Entire result suggests the possibility of selecting the desired pollen grains from a pollen population and possibility of attempting selective pollination in carnation breeding program.

The effect of fluridone (or flurochloridone), the inhibitor of carotenoid, chlorophyll and abscisic acid synthesis, on the abscission of Ligustrum vulgare leaves was investigated. Both forms of fluridone inhibited the abscission of petioles when they were applied as a 1.0% concentration in lanolin to the leaf blade. Fluridone was capable of inhibiting abscission even when it was applied to the petiole as late as 7 hours after the blade was cut off. Fluridone applied in lanolin to the apical part of intact pea seedlings or on the cut surface after decapitation of the epicotyl caused albinism of the stipules. The degree of albinism decreased according to the concentration of applied flurodine (from the highest - 0.5% to the lowest - 0.03%) and was higher in intact than in decapitated plants. Albinism also appeared in pea seedlings grown from seeds swollen in differently concentrated solutions of flurochloridone, particularly in the basal part of the shoots. Complete albinism occurred only in plants cultivated from seeds swollen in high concentrations (0.06-0.12%). The lowest concentration (0.007%) stimulated root growth of the pea seedlings, but inhibited epicotyl growth.

Problems concerning total dry weight and distribution of underground phytomass were studied in a pasture trial at Rapotin near Šumperk, the CzechRepublicin the period 1995-1999. The total weight of dry underground pasture phytomass (DUP) was 976 g/m² (5-year average) in a soil layer of 0-200 mm (both live and dead roots). The DUP was significantly increased by mineral fertilizers (90 kg N/ha, 30 kg P/ha a 90 kg K/ha). The weight of DUP was not significantly influenced by a grazing system, renewal or resowing of the original grassland. In unfertilized plots, DUP weight amounted to 989 g/m², i.e. 92 g/m² (8.6%) less than in fertilized plots in the period 1996-1999. In the same period, under the grassland exploited by rotational grazing 1142 and under continuous grazing 1082 g/m² DUP were determined, i.e. by 60 g/m² (5.5%) less. The highest DUP weight in the period 1996-1999 was found in autumn 1997 (1222 g/m2) immediately before achieving the maximum forage yield in May 1998. In a layer of 0-20 mm, 54.6% of the total DUP was found. In this surface layer, significant increase in the DUP weight was found in fertilized plots. In 1999, some 88.5 and 90.2% of DUP were concentrated in unfertilized (903 g/m²) and fertilized (952 g/m²) plots, respectively in a layer of 0-100 mm.

The observations were conducted on chernozem soil in a sugar-beet production region in 1971-2002. Six variants of organic amendment were examined: l - straw harvest, 2 - straw harvest + green manuring, 3 - straw incorporation, 4 - straw incorporation + green manuring, 5 - straw burning, 6 - straw burning till 1977 + intercrop, incorporation of farmyard manure at 10 t/ha since 1978. The effect of organic amendment on winter wheat continuous cropping was statistically significant. On average of the whole period (32 years), the highest yields were produced in variants with straw burning (var. 5) - 6.04 t/ha and with green manuring (var. 2) - 6.03 t/ha, and lower yields in variants with straw incorporation into soil (var. 3) - 5.65 t/ha, (var. 4) - 5.67 t/ha. The smallest differences between variants were found in the first decade of the experiment. Over time (in the second and third decades), the differences increased and positive effects of green manuring and straw burning and adverse effects of straw incorporation into soil increased. The yield level of winter wheat continuous cropping was high under the given conditions. The yield for the whole period of the experiment averaged 5.85 t/ha, the yields 5.19, 6.54 and 5.76 t/ha were obtained in the first, second and third decade, respectively.

Partial characterization of iron binding compounds in spinach above ground biomass and differences between binding of Cd, Zn and Fe in spinach biomass were investigated on two soils treated by sewage sludge in model pot experiment. After application of sludge to both soils, Cd and Zn accumulation in spinach biomass was increased in sludge treatments. Total Fe content in biomass showed opposite trend with these treatments and was decreased 2.5-2.7 fold. Results of sequential analysis of spinach biomass showed lower portions of iron in all individual fractions of both sewage sludge treatments compared to control treatments. The largest differences in iron content between control and sludge treatments were determined in ethyl acetate fraction. While majorities of Cd and Zn were found in fractions methanol + H2O and H₂O and methanol + H₂O + HCl, iron content determined in these two fractions was only 7-8% in control treatments and 15-20% in sludge treatments of total iron. In fraction, Fe portion was 87.7-90.7% in treatments without sludge and 76.1-83.5% in sludge treatments in spinach biomass. Results showed tighter iron binding to plant cell membranes in contrast to cadmium and zinc.

Four kinds of cereal crops were grown without farmyard manure application. The effect of farmyard manure was supposed to be replaced by post-harvest residues (PH treatment) or by ploughing the total by-product, i.e. straw (PZ treatment) into soil. After seven years of application, this soil farming system did not influence the contents of Cox and Nt in soil. The amount of organic carbon had declined after the first year, but in the following years it remained at the same level (1.2%). The total nitrogen content increased from 0.143 to 0.166% without any considerable difference between the treatments. The amount of microbial biomass (C_mic) in PH treatment had been varying and in 2000 it decreased approximately by a half (from 215.96 to 132.00 mg C/kg of soil dry matter). The input of organic matter due to ploughing the whole by-product (PZ treatment) into soil acted favourably and the value of C_mic in 2000 was quite comparable with the average values of the individual years of 1994-1997. This land management and cereal growing caused a reduction of the ratio of microbial biomass carbon to soil organic carbon (C_mic/C_org). In the year 2000, the values decreased from 2.59 to 1.09% and from 2.88 to 1.82% in PH and PZ treatments, respectively. The amount of the biologically releasable nitrogen (Nbiol) and the intensity of nitrification were the highest in the year 2000. There was a moderate negative correlation (r = -0.474) between the N_biol values and biomass amount values in PZ treatment, and a very close negative one (r = -0.972) in PH treatment. This relation became strong in both treatments when the values Cmic/Corg and Nbiol were compared, i.e. r_PH = -0.863 and r_PZ = -0.921. The results confirmed that the amount and the quality of organic matter influence microbial biomass and its activity which is responsible for the nutrient release.

Changes in N-NO3- content and N-NO3- increase after incubation were studied in 1992-1998 in soils of two farms situated in identical soil and climatic conditions (in spring and autumn seasons). The two farms produce sugar beet and grain crops, but since 1991 they have used different types of organic fertilizers. Farmyard manure has regularly been applied to root crops on Dobrá Voda farm; since Chvalina farm does not have animal production, green manure and plowing-in of beet tops and straw are used for organic fertilization. Soils with regular applications of farmyard manure show a trend of lower N-NO3- content than the soils of the farm without animal production. At Dobrá Voda N-NO3- content was about 12 ppm N in spring and 9 ppm N in the autumn season while the respective values for Chvalina were 14 and 10 ppm N. On the hand, N-NO3- increase after soil incubation (12-14 ppm N) was higher in Dobrá Voda soils than in soils from Chvalina farm (5-8 ppm N).

The Pb, Zn and Cd phytoextraction potential of 14 different plants was assessed in a chelate induced phytoextraction experiment. In the used soil heavy metals mainly reside in carbonate, organic matter, and residual soil fractions. The addition of a chelate, 5 mmol/kg ethylenediamine-tetracetic acid (EDTA), increased the proportion of phytoavailable Pb, Zn and Cd in the soil (dissolved in soil solution and exchangeable from soil colloids), and also their uptake by tested plants up to 48 times (Sinapis alba), 4.6 times (Raphanus sativus oleiformis), and 3.3 times (Amaranthus spp.), respectively, compared to the control. The biodegradable chelate ethylenediamine-disuccinic acid (EDDS) was generally less effective (tested on a selection of 4 plant species), except for Cannabis sativa. In a treatment with 10 mmol/kg EDDS, Pb, Zn and Cd concentrations of 1053 ± 125, 211 ± 16 and 5.4 ± 0.8 mg/kg, respectively, were measured in the biomass of Cannabis sativa and were 105, 2.3 and 31.7 times higher, respectively, than in the control treatment. The calculated Pb phytoextraction potential of Cannabis sativa amounted to 26.3 kg/ha.

A survey was made to evaluate sanitary status of grapevines in the Czech Republic with regard to occurrence of economically important viruses. Propagation material of 109 grapevine clones was tested for presence of Grapevine fanleaf virus, Arabis mosaic virus, Grapevine leafroll-associated virus 1, Grapevine leafroll-associated virus 3, Grapevine virus A, Grapevine virus B and Grapevine fleck virus. Dormant canes were collected and cortical scrappings were analyzed by DAS-ELISA. All seven viruses tested were found to be widely spread in Czech propagation material of grapevine. From 330 individual vines tested, 148 vines were found to be infected with at least one virus. From 109 clones tested, in 98 clones at least one vine negative for tested pathogens was found. Such vines were promoted as candidate plants into screenhouse in Faculty of Horticulture Lednice and will be further tested by other methods. Sanitation of infected grapevine clones is needed in near future.

Zinc distribution in the main soil fractions and zinc accumulation in potatoes, maize, wheat and barley after different soil treatments (basic sludge rate, triple sludge rate, NPK, NPK + inorganic Zn) were investigated in a field experiment conducted at five localities of the Czech Republic (Červený Újezd, Hněvčeves, Humpolec, Lukavec, Suchdol) with different soil and climatic conditions. Three soil types were investigated in the experiment: clay-loamy Chernozems, loamy Luvisols, clay-loamy Luvisols and two loamy Cambisols. Sequential analyses provided an overview of soil Zn distribution in the following fractions: exchangeable, Fe-Mn oxide, organic and residual ones. The sludge and inorganic Zn addition supported Zn mobility growth and higher Zn retention in Fe-Mn oxides in all tested soils. The influence of the above-mentioned treatments on higher Zn association with soil organic compounds was not explicitly found. Potatoes, wheat and barley accumulated more Zn after its addition into the soils by sludge and inorganic salt. By contrast, Zn content in maize decreased with higher input of Zn into the soil. The highest Zn concentrations were usually observed in plants grown on both Cambisols.

Two methods were developed and tested for the measurement of the mowing machine material feed rate (based on the conditioner power input measured by a torque-meter, and/or on the material change in momentum measured by a curved impact plate). The measurements carried out in the year 2001 proved that a very good linear relationship existed between the conditioner power input, output frequency of the apparatus measuring the impact force by means of the impact plate, and the material feed rate through the mowing machine. The calculated R-Squared values were about 0.95. In the year 2002, the impacts of material and condition (parameters) changes on the mowing machine material feed rate measurement accuracy were measured under laboratory conditions. It was evident from the statistical evaluation that changing crop variety, crop maturity, and intensity of conditioning can have a statistically significant influence on the measurement based on the torque-meter. As concerns the impact plate measurement, it was found that it is not possible on the basis of our measurements to determine statistically the influence of the factors tested.

This paper deals with the recent sissoo (Dalbergia sissoo Roxb.) decline in the plain land (locally called as terai) of Nepal. This study has made an attempt to find the possible causal factor of this decline. The study has made some initiative in this aspect and has made a comparative study of 30 different sissoo forest (both natural and plantation) stands. The symptoms of the sissoo decline were found to be varied. But in most of cases, the top dying of crown was found to be the most prevalent. The top dying starts from the top of the tree and progressively proceeds downwards to the stem. The leaves become yellow. Until now, it has been assumed that only the plantation forests have been affected but this study observed the sissoo decline also in natural forest sites. We analysed various components of physical soil characteristics and we did not find any correlation between the physical soil factors and the sissoo decline. We concluded from this study that the soil is not the sole responsible factor involved in the sissoo decline Furthermore, this paper discusses various aspects of the sissoo decline and possible causal factors concerned. Finally, future management strategies regarding the sissoo management are suggested.

The level of the usage of information and communication technologies (ICT) has a direct influence on the development and competitiveness of individuals, firms, production sectors, regions and even the whole continents. The availability of ICT, including the Internet, to agricultural enterprises in theCzechRepublicis already very satisfactory. Due to the structure of agricultural enterprises the penetration of Internet technologies in theCzechRepublicis more intensive than in most EU countries. Therefore an urgent issue is the level of the usage of these technologies that is not an issue related to finances anymore but it is a problem related to the knowledge and habits of users and availability of information and services. The project of the portal for the agriculture sector and countryside AGRIS has a significant impact on the level of the usage of Internet information and services in the agriculture sector.