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We have used a combination laser/electrospark method for fast determination of carbon content in soil. Excitation of the spectra is carried out both directly in a laser ablation plume and when a pulsed electric discharge is applied to it. We have plotted a calibration curve that is linear for the major concentration range of practical importance for the analyte element, all the way up to 8.6%. The carbon detection limit for the combination discharge approach is 0.07%. We have analyzed the ratio of the nitrogen and carbon contents, and also the hydrogen and carbon contents as a function of the carbon concentration in the studied soils samples.Description of the Method. The laser spectral analysis method (LIBS, laser-induced breakdown spectrometry) essentially involves exposure of the analyte sample to a focused high-power laser radiation flux, ablation of the sample material and formation of a plasma plume, the luminescence spectrum of which is recorded by a detector and processed by a measurement system [1][2][3]. Generally the amount of the material entering the plasma plume is fractions of a microgram, so LIBS is actually considered a nondestructive method.Broad development and application of LIBS began as a result of technical upgrade and expansion of production of high-power laser radiation sources based on yttrium aluminum garnet operating in the frequency regime. An important role was played by development of semiconductor 2-D array optical signal detectors, systems for data accumulation and processing, and optical instruments with high spectral resolution. Expansion of the area of application of LIBS is also due to more thorough study of the laser plasma itself: methods have been refined for determining the electron concentration and temperature of the plasma plume, self-absorption of emission spectral lines, the presence of local thermodynamic equilibrium (LTE). Thus the foundations have been laid for determination of the elemental composition of analyte objects without using certified samples [4,5], although the latter have maintained their role in validation of LIBS methods and also in cases involving analysis of samples of rather complex composition. The correctness of the results obtained by LIBS in the standard-free variant can be ensured, in the absence of matrix effects, when stoichiometry is satisfied in the composition of the plasma and the test object, which is possible when the power density of the laser radiation is at a level higher than 1 GW/cm 2 .In order to improve the sensitivity of LIBS, "dual" laser pulses are used [6,7], i.e., a second laser pulse is applied to the ablation plume with a certain time delay, which excites the material vaporized by the precursor in the relatively rarefied state of the vapor/gas atmosphere; in this case, robustness of the discharge is increased, re-absorption of the spectral lines is reduced.LIBS is a very promising method for solving practical problems in many areas of science and technology: quality control for industrial production, the composition of c...

Aim. The aim of this study was to carry out passportization of cultivars, varieties and hybrids of perennial grass crops: Alopecurus protensis, Agropyron cristatum, Lolium perenne, Lolium miltiflorum, Festuca protensis, Festuca arundinasea, hybrids Festulolium. Methods. The perennial grasses selection was carried out by embryo culture according to methodical recommendations. For the molecular-genetic passportization of perennial grasses varieties the polymorphous primers have been selected – 9 RAPD primers and 15 ISSR primers. Results. Multilocus DNA labeling have allowed to differentiate all the genotypes being studied, to develop and to create the unique profiles for each of them and to calculate the genetic distance of congeniality/distances. On the base of RAPD/ISSR, SCoT spectra the 14 molecular-genetic passports of perennial grass cops have been obtained for the first time. Keywords: grass crops, molecular-genetic passport, DNA, PCR, multipoint mapping RAPD/ISSR spectra.

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Aim. To form the varietal population of festulolium intergeneric hybrids of Festuca arundinacea morphotype. To carry out DNA-labeling of created festulolium hybrid plants and parental forms. Methods. The festulolium intergeneric hybrid’s creation was carried out by embryo culture method from an immature caryopsis by growing on a nutrient medium. For the plant genotypes labeling the multilocus primers associated with coding DNA regions (Start Codon Targeted (SCoT) Polymorphism), SRAP (Sequence-related amplified polymorphism) have been selected. Results. The viable plants of intergeneric festulolium hybrids of Festuca arundinacea morphotype have been obtained. To select the best festulolium biotypes for variety populations with high feed and seed productivity formation. A system for hybrid plants genotypes and their parental forms registration in the form of molecular genetic passports have been elaborated. The genetic passports reflects the allele’s composition in loci associated with DNA coding sequences. Conclusions. The best biotypes with economically valuable traits were selected and included in the further selection process. The molecular genetic passports of hybrid festulolium plants and parental forms were composed. Keywords: festulolium, immature caryopsis, biotypes, DNA, PCR, molecular genetic passports.