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Changes of soil organic matter (SOM) parameters were investigated in a haplic Luvisol with medium-heavy texture. Soil samples were taken from several layers at minimum (MT) and conventional (CT) tillage plots of a field experiment in Sitzenhof (Germany). All cultural practices except for tillage (crop rotation, fertilizing, protection measures, etc.) were identical over the whole time of the experiment. The concentrations of oxidizable carbon Cox and its constituents (humic acids (HA), fulvic acids (FA), and hot-water soluble carbon) are comparable in layers 15-20 cm in both variants. In 0-15 cm and 30-55 cm layers, these concentrations were higher in the MT variant. A similar trend was observed in the colour quotient values of humic substances Q4/6, which indicates increasing condensation of humus substances (HS) at deeper layers in both variants, and it is also confirmed by a humic to fulvic acids ratio HA:FA. Concentrations of SOM fractions were higher (except 15-20 cm layers) in the MT than CT treatment throughout the profile, especially below the 30 cm depth. The SOM did not accumulate markedly in the surface layer of long-term MT treatment.

The objective of the present paper is to contribute to the evaluation of quantity and quality of non-humified part of soil organic matter (SOM). In samples of soil organic matter from the humus profile of Šumava forest soils and forest meadows, taxonomically designated as mor and moder forms, the fractions of labile soil carbon Ccws, Chws, CPM and fraction of stable carbon represented by carbon of humus acids CHA and CFA were determined. Organic matter of samples was fractionated according to the degrees of hydrolyzability by two different methods in particle-size fractions of 2.00-0.25 mm and < 0.25 mm. The quality of labile fraction Chws was expressed on the basis of reaction kinetics as the rate constant of biochemical oxidation Kbio and rate constant of chemical oxidation Kchem of the first order reaction from a reduction in the concentration of C-compounds. The highest values of labile forms of carbon were determined in samples with the least favorable conditions for transformation processes of SOM, and these samples also had the highest content of labile forms in hydrolyses by both methods and the most labile fractions at the same time. The degree of SOM humification was strictly indirectly proportional to the lability of SOM and its hydrolyzability. The quality of labile fraction Chws can be expressed by both Kbio and Kchem while the sensitivity of Kbio is higher but the reproducibility of Kchem is better. Kbio corresponds with the degree of SOM transformation, Kchem with the proportion of CPM in total Cox.

In breeding of winter rape (Brassica napus L. var. napus) using the OGU-INRA system, based on cytoplasmic male sterility (CMS), it is necessary to distinguish pollen-sterile lines, carrying CMS factors and the recessive fertility restorer alleles rfrf, from fertile lines, carrying at least one dominant restorer gene allele (Rfrf or RfRf). To grow plants till the flowering stage takes much time. The method was therefore modified using isozyme markers of glucose-6-phosphate isomerase (PGI) to distinguish male sterile (MS) from male-fertile lines in early stages. Since the restorer gene is tightly linked to the markers and the PGI isozymes can be distinguished by electrophoresis, the markers can be used to identify MS rape plants in early stages. Also, homozygous and heterozygous fertility-restored plants can be separated this way. In our work we tried to optimise the distinction of pollen-fertile and pollen-sterile rape plants with PGI isozyme markers, using vertical polyacrylamide gel electrophoresis (native-PAGE). The method will be used for the breeding of rapeseed with the OGU-INRA system.

Genetically modified organisms have become a part of our environment and food chain. Roundup Ready soybean is at the moment the most frequent one that man can meet. National regulations require careful monitoring and detection of GMOs. We present in this investigation comparison of several protocols and individual steps, which are included in the whole detection procedure. Currently used CTAB based protocol is suitable for DNA isolation from the green plant tissue but also from the flour. Lectin coding sequence specific primers were suitable for soybean DNA detection unlike leu-tRNA gene specific primers. Only one of the tested CaMV sequence specific primer pairs did not amplify unspecific products under condition tested. NOS terminator specific primer pair was found suitable for routine screening. EPSPS gene was detected using two different protocols; the same primers did not identify other Roundup Ready GM crops.

Lutein and β-carotene contents in 32 samples of field peas with green (

Total starch (TS), amylose and resistant starch (RS) were determined in the sets of smooth pea and wrinkled pea varieties in the years 2006-2008. Starch content of smooth peas varied in the range 53.61-57.23%. Average amylose content was 27.8%. Resistant starch content varied from 2.07% to 6.31%. Content of starch at wrinkled pea varied from 26.57% to 32.55%. Average amylose content was 76.82% of total starch. Content of total starch increases continually during seed development. The dependence of total starch on determined dry mass in harvested sample can be defined by equation γ = 1.2427 × -6.5611, by determination coefficient R2 = 0.8936 and highly significant correlation coefficient r = 0.945. Total starch content in dry seed reached final average value 29.56%. In garden pea, the level of maturity (by tenderometric measurement) and dry matter were determined. Resistant starch content of 11 garden pea cultivars was studied in three different terms of technological harvest.