
Progressive methods of molecular analyses of DNA are routinely used in the fields of zoological and botanical taxonomy, pest management and plant breeding. Knowledge of species-composition in populations of potato cyst nematodes (Globodera rostochiensis, G. pallida) is very important for selection of appropriate measure of regulation PCN's occurrence. The molecular method for distinguishing of PCN species is described in this article. European populations of PCN - Šluknov (Ro1), Obersteinbach (Ro2), Harmerz (Ro5), Kalle (Pa2), Chavornay (Pa3), Delmsen (Pa3), and some cysts of unknown pathotype from Kašperské hory (K) locality were used. Species-specific sets of primers for ITS-1 (Internal Transcribed Spacer 1) amplification were designed on base of known sequences ITS-1 of both PCN species by using of freeware Primers! for the World Wide Web. By using of set Fro1-Rro1 was product 411 bp detected (only in cause G. rostochiensis), by using of set Fpa2-Rpa1 the product 239 bp was detected (only G. pallida). For these reasons the identity of the European populations was confirmed. Cysts of population K were identified as G. pallida.
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.
Marker assisted selection is the fast and objective method for detection of resistance major genes. This method is practical for identification of some candidate genes of quantitative resistance. Genetic markers based on Polymerase Chain Reaction (PCR) were used for evaluation of F1 progenies Ornella × Mira and Tábor × Mira. Cultivar Mira has resistance against Ro1 pathotype G. rostochiensis. Cultivars Ornela and Tábor are susceptible to Ro1. Seedlings of F1 generations were used for analyses. Plants were cultivated in greenhouse. DNA was isolated from tissue discs by GenElute Plant Genomic DNA Kit (Sigma, SRN). PCR marker of major gene H1 was used for bulked analyses, according to (Niewöhner et al. 1995). Size of this marker was 760 bp. Standard infection tests with Ro1 pathotype G. rostochiensis according to Potoček (1987) in all of the analysed genotypes were made. Segregation ratios of F1 progenies were determined. These ratios have described segregation of resistance markers and segregation of traits in the biological test. The both methods of evaluation of potato's resistance were compared by correlation analyse. High correlations were found between occurrence of PCR marker for H1 and resistance to Ro1 in biological test. Coefficient of correlation r = 0.962 in F1 progeny Ornella × Mira and r = 0.964 in hybrids Tábor × Mira. Statistical evaluation of real ratios of segregation by infection tests and DNA markers with theoretical ratios of segregation in simplex and duplex H1 gen qualitative determined resistance was made as well. Resistant cultivar Mira as donor of simplex determined resistance was confirmed.
The effect of sewage sludge application on three soils of different properties (Chernozems - location Suchdol, Luvisols - location Cerveny Ujezd and Cambisols - location Humpolec) was investigated in pot experiment and the accumulation of Zn in above ground biomass of oat as well as availability of Zn released by 0.01 mol.1(-1) CaCl2 was evaluated. Stabilised sewage sludge was obtained from three wastewater factories in Czech Republic. Sewage sludge has been preincubated with addition of limestone and lime (7% of Ca w/w of sludge dry solid) in aerobic and anaerobic conditions and tested in pot experiment. The highest Zn mobility reduction was found at Humpolec soil. Sludge amended by lime and limestone reduced available Zn content in this soil (at sludge III by 86% after limestone and by 71% after lime application). Considerable reduction of Zn in plant showed in Humpolec soil treated by sludge with lime (by 20% compared with soil treated by nonincubated sludge - control) and limestone (by 30% after anaerobic incubation compared to control). The positive incubation and treatment effect was not confirmed in the other soils. Available Zn in Humpolec soil showed the strongest correlation among all soils with total Zn content in plant (at aerobic treatment R-2 = 0.66 and at anaerobic R-2 = 0.83).
The laboratory incubation with glucose treatment was carried out in order to estimate the possible effects of increased microbial activity on heavy metal availability. The soils from vicinity of a lead smelter operating for more than 200 years were used for the experiment. The DTPA-extractable heavy metal contents increased after glucose addition and mostly reached the highest values the second day of the incubation. The comparative study, where the chloroform fumigation was used prior to the incubation in order to decrease the microbial activities, showed especially from second day of incubation significantly lower DTPA-extractable metal contents compared to non-fumigated treatments. The interactions among the maximum possible availability of DTPA-extractable heavy metal fractions and native soil microbial characteristics were studied in differently contaminated arable and grassland soils. Irrespective of different heavy metal contents in soils, significant correlations were found among the maximum percentage increase of DTPA-extractable Pb and Cd and the ratio Bc/TOC and metabolic quotient (qCO2) which may be a result of the important role of organic matter and microbial characteristics in soils on the heavy metal availability.
Vicine and convicine were isolated from mature seeds of Vicia faba L. These compounds were separated from the relevant fractions by HPLC and identified by IR, MS and NMR. Obtained vicine was used for all bioassays. Vicine in concentration of 25 µg in 1 ml of medium had significant toxic effect. The concentration of 5 µg of vicine in 1 ml of medium had significant fungistatic effect for fungi Fusarium culmorum and Alternaria alternata. The concentration of 500 ng of vicine in 1 ml of medium had significant fungistatic effect for fungi Cladosporium herbarum and Botrytis cinerea. The effective concentration of vicine in our test was significantly lower than is the concentration of vicine in seeds and pods of V. faba. The toxicity of vicine comparing with the toxicity of insecticide Actellic was higher by one order. Also, the fungicide Impact had a lower toxicity than vicine. Fungitoxic and fungistatic effect of vicine was comparable with some other tested fungicides and with the plant saponin digitonin. Our results confirmed that vicine is important natural fungicide.
The influence of long-term regular mineral fertilization on the soil environment considering the total sulphur and the sulphur balance in the habitat of the permanent mountain meadow was investigated. The experimental field (set up in 1968) is situated at Czarny Potok (20°8' E, 49°4' N) in the central part of the Polish Carpathian. With completed annual NPK fertilisation 1.8 kg S/ha was introduced into the soil. The highest sulphur amount was found in the 0-10 cm horizon and this value slightly exceeded the content considered as natural. The sulphur content in the sward from Czarny Potok was lower than the mean sulphur content calculated in Poland for grasses (0.21% S). In the case of full NPK fertilisation the amount of removed sulphur ranged from 11.4 to 14.0 kg S/ha. The mean sulphur leaching into the soil profile from surface of 1 ha can be estimated from 1.1 to 3.7 kg S/ha.
Four variants in four replications were studied on permanent meadow stand oil Czech and Moravian highlands. The altitude a.s.l. is 485 m, original growth type was Dactylidetum, association Trifolio-Festucetum rubrae. Four variants: control (without fertilization), 40 kg P + 100 kg K.ha(-1), 100 kg N.ha(-1) (+ PK) and 200 N.ha(-1) (+ PK) were evaluated. Botanical analyses of stands were done by the method of reduced projective dominance (D in %). The cut green matter was weighed up, mean samples for dry matter determination and chemical analyses were taken. Botanical composition of the meadow stand in 1991-2000 was not stabile and was changing due to nourishment. The yields of dry matter ranged within 10 years in the control variant from 1.07-3.42 t.ha(-1) (in the plot fertilized by P40K100 2.09-5.95 t.ha(-1), in the plots with nitrogen (+ PK) 2.29-6.52 t.ha(-1), resp. 3.74-7.61 t.ha(-1)). According to the t-test, the yields of dry mass in experimental variants are significant at 95% level.
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.
Samples of soils and surface waters were analysed in the Šumava foothills region in nine watersheds with an area 78.5 km2 in 1986-1987 and in 2001. Lower intensity of fertilization and liming and other changes in Czech agriculture were found to result in a decrease in the content of cold and hot water soluble carbon (Cw and Chws) in the soil; the content of biologically decomposable matter expressed as BOD5 and BODt of water extract of soil also decreased. The values of rate constants k of BOD kinetics of soil suspension indicate that the most valuable fast decomposable organic matter in the soils of this region have practically been mineralized to HCO3-, which are gradually eluted from soils and their increased amounts are present in surface waters. On the contrary, the transport of N-NO3- decreased to 66.3% of the value in 1986, that of N-NH4+ to 7.1% while the ratios C:N and N:P increased as a result of lower P elution in relation to lower N elution. CODMn showing the proportion of readily decomposable matter increased. A decrease in conductivity, i.e. in the content of dissolved salts in waters, was highly significant. These results warn against an optimistic interpretation of surface water analyses that indicate positive impacts of farming intensity reduction on the landscape. The results in the Šumava foothills region demonstrate that a major part of the most valuable components of soil productivity, decomposable organic matter, has already been decomposed, so their content in the soil has decreased. Natural sources (roots, root exudates, plant residues) are not able to ensure an equilibrium balance of these valuable matters at a lower farming intensity.
The development of soil limiting values of the protection of the quantity and mainly quality of the crop production tends from empiric values towards critical values, based on ecotoxicity. We present an attempt to derive transfer functions by the means of multiple regression analysis. The substitution of trace elements contents in crops in the prediction equations for fodder or food standards or phytotoxicity limits satisfies the present ecotoxicological demands. We preferred polyfactor relations to simple ones. The exceeding of reference values must be verified by the determination of the hazardous transfer in the field. Therefore the reference values are called testing values. They were derived especially for Cd, Pb, As, Cu, Zn, Ni and Mn. For some trace elements, only protective values can be set up (especially for Cr, Hg, but also for Tl, Be, V). They reflect minimum values that guarantee growing crops without any risks. Experimental data (pot trials) were compared with results obtained in field investigations. The resulting critical values were also compared with the values proposed in Germany.
Glucosinolates are the substituted esters of thio amino acids and their synthesis is based on the corresponding amino acids. Methionine and cysteine are the natural donors in the case of the Brassica plants and L-tryptophane in the indole glucosinolates, respectively. In Brassica genus, alkenyl glucosinolates are mostly present and their content and composition differ as far as the development stage and the part of the plant are concerned. The indole glucosinolates are present in a minority level. Their role of sulphur supply is questioned by their very low content between 2% in the beginning of vegetation and 0.1% in its end. Glucosinolates are discussed mostly from the aspect of their anti-nutrition, anti-microbial, anti-fungicidal, and anti-bacterial effects and as being natural bio-fumigants. Their decomposition products have the mentioned properties. The products originate by prepared passive protection by the two-component system. From the aspect of these properties, it is useful to divide them into the following three groups according to the characters of their decomposition products. The first group (I.), whose hydrolysis in the neutral and alkaline environment creates iso-thio-cyanates. These bioactive compounds form the natural protection of the plant with bio-fumigatory effects particularly. Their anti-nutritive effects can be compensated by iodine, contrary to the second group (II.). This group is created by hydroxy-glucosinolates, whose decomposition products - iso-thio-cyanates - are not stable and they cycle while producing substituted 2-oxazolidinethione (goitrine - VTO). These glucosinolates represent a serious problem in feed industry since the VTO has a strong goitrogenic property. The third group (III.) - glucosinolates containing the indole group or the benzene ring (Sinalbin), create thio-cyanates during their hydrolysis. The role of indole glucosinolates has not been completely clarified so far. Their anti-carcinogenic effects are studied and they fulfil the role of an active protection.
The need for vernalization of winter wheat varieties cultivated in the Czech Republic in 2000 was studied in comparison with the need for vernalization in the past decades since 1950. In 2000, many foreign varieties were cultivated in the Czech Republic, mostly West European. Varieties with a vernalization of 40-50 days and 50-60 days show the highest representation in the assortment (47.3% and 31.6%, resp.). The share of varieties with a long vernalization over 60 days is 15.8%. In around 1990, when varieties of domestic breeding were mostly grown, there were, next to the largest group with a vernalization of 40-50 days, 21.7% of varieties with a vernalization of 30-40 days and the same amount with a vernalization of 50-60 days. During the last ten years, the share of varieties with a longer vernalization has risen, not only due to foreign varieties, but also due to new domestic varieties. It is apparent from a 50-year overview that what has predominated are varieties with a vernalization of 40-50 or 40-60 days, which is a range usual for winter varieties of wheat in Middle and West Europe. After 1950, a departure from original domestic varieties appeared; those were represented by original alternative varieties (in Czech poesfvky, in German Wechselweizen, in Russian dvurucki) and half-winter varieties with a shorter vernalization, strictly speaking with a vernalization fixed to a short day, and a strong photoperiodic reaction. Representation of varieties as related to their length of vernalization has changed in the course of the decades following utilization of foreign varieties; this was affected above all by varieties from Russia (the former USSR), Germany, but also Yugoslavia. Varieties from these countries were utilized also as parent components in domestic breeding.
In the case of cadmium transport via soil macropores, the short-term duration of an interaction between the reactive solute in aqueous phase and soil, as well as cadmium precipitation or adsorption on particles < 10-5 m should be taken into account. Two distribution coefficients are proposed for predicting the cadmium transport in a structured soil: the matrix distribution coefficient Kdm, equal to the equilibrium distribution coefficient Kdeq and estimated using the conventional batch technique, and the macropore distribution coefficient KdM, estimated using the modified batch technique. It was found that the conventional approach (using the coefficient Kdeq only) would underestimate a penetration of the part of Cd transported in the macropores about 255-times in the loamy-sand soil in Kalinkovo, 20-times in the loam soil in Macov, and 122-times in the clay soil in Jurová in comparison with the approach proposed in this study.
Microbial solubilization of hardly soluble mineral phosphates in soil is an important process in natural ecosystems and in agricultural soils. Regulation of the P-solubilizing activity by the presence of soluble phosphates in medium was determined. For this reason we decided to test a number of soil bacteria showing a high P-solubilizing activity for its sensitivity to the presence of soluble dihydrogen potassium phosphate in medium. At these studies, the direct determination of the solubilized phosphate in medium was masked by the presence of relatively high concentrations of soluble phosphate added. Therefore, we have modified the method, determining the residual tricalcium phosphate. The effect of soluble phosphate in medium on the P-solubilizing activity of rhizosphere isolates and strains of Rhizobium were tested in liquid cultures with the addition of various concentrations of soluble KH2PO4 The, medium was filtered after incubation and the remaining tricalcium phosphate was separated by filtration. Filter papers with the remaining tricalcium phosphate were hydrolysed with 2N H2SO4. Phosphorus was determined spectrophotometrically. The P-solubilizing activity was expressed as a difference between the tricalcium phosphate added and its remainder after the incubation. These results fully confirmed that there exist the strains, whose P-solubilizing activity is inhibited and other strains, whose P-solubilizing activity is not inhibited or is inhibited very little in the presence of soluble phosphate. The use of our adapted method was much more suitable for this type of experiments.
During the years 1998-2000 soil chemical (Corg, Nt, pH), textural (sand, silt clay) and microbiological (microbial biomass carbon - CMB, microbial extracellular carbon - CEX, respiration, ammonification, nitrification) characteristics were tested on grassed chernozem [mollisol] after arable land setting-aside. Different harvest management was also tested: black and green fallow, one or two mulching per year, three cuts with plant biomass removal. For the evaluation of the influence of management and plants we have used three main criteria: (1) µg CMB/g dry soil, (2) ratio CMB/Corg (%), (3) µg CEX/mg CMB or eight criteria respectively: (4) ratio of measured and model values of CMB, (5) ratio of measured and model values of CEX/CMB, (6) potential respiration with glucose, (7) potential ammonification with peptone and (8) potential nitrification with (NH4)2SO4. According to these criteria, the best harvest management after arable land setting-aside from 5 different systems, which were tested, could be based on one or two mulching per year. It could be stressed that the two mulching was evaluated as the best in sum of dry mass yield (27.5 for mixtures, 20.1 for legumes and 14.2 for grasses - in t/ha/3 years). The use of legumes (Trifolium repens L. - Medicago lupulina L. - Lotus corniculatus L. - Medicago media Pers.) or grasses [Bromus catharticus Vahl - Arrhenatherum elatius (L.) Presl - Festuca pratensis Huds - Dactylis aschersoniana Graebn.] as cover plants was more successful than the use of their mixtures.
In field trials in 1998-2000, ten varieties of the world collection of birdsfoot trefoil (Lotus corniculatus) were evaluated for herbage and hay yields. In all the years of testing yields from three cuttings and total annual production were evaluated. In 1999, seed yield was also recorded. As a control, alfalfa (Medicago sativa) variety was included in the experiment. The test varieties showed good productivity in the first and especially in the second year of testing, most of them exceeded alfalfa in herbage yield in individual cuttings and in total productions. As for hay yield, the differences were not so great. Local varieties showed very good productivity, predominantly in herbage yields. Of foreign varieties, the best herbage, hay and seed yielder was the Hungarian variety Puszta. There were no statistical differences in seed yield between the varieties. The yields were, however, relatively low.
Five fertilization systems and seven types of growing substrates were tested with two woody plant species with different nutritional demands (Thuja occidentalis, Pyracantha coccinea) grown in two-litre containers.The experiment was repeated in two vegetative seasons.Application of controlled release fertilizer (CRF) was proved the most reliable; it gave good or at least average results in dependence on used growing substrates.Significant differences between application of CRF and other fertilization systems were with Pyracantha plants.System using slow release fertilizer with additional nitrogen fertilizing also showed good results.Systems based only on liquid feeding were less reliable, with some substrates they showed very good results; with others (peat substrate, peat bark substrates with wood components) they were bad.Similar results were achieved with top dressing of granulated fertilizer.Evaluating the substrates good results were obtained by using mixtures of peat with components with higher content of nutrients -peat bark substrates, peat bark substrates with compost and nonpeat mixtures of composted bark, wood fibres and compost.Significant differences between these types of substrates and peat one or peat bark substrate with wood components were both with Thuja plants and especially with Pyracantha plants, which have higher demand for nutrients.The experiments showed that peat based substrates amended with alternative components or non-peat substrates can bring better results than the peat ones.