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Long-term field experiments provide a valuable dataset for predicting changes in soil organic carbon (SOC) stocks in different agricultural systems. The RothC-26.3 model was used to simulate changes in SOC in the monoculture of spring barley (Hordeum vulgare L.) and the Norfolk crop rotation during 1972-2100. The potential of the Gleyic Fluvisol Clayic to sequester organic carbon was investigated. The studied soil was heavily textured, with medium organic carbon content. Four management scenarios in the monoculture and six management scenarios in the Norfolk crop rotation were evaluated. Three different global climate models (MPI, MRI, CMSS) representing the uncertainty of future climate conditions were used. Results showed that carbon stocks were mainly influenced by plant residue inputs and exogenous organic materials application. The projection showed trends of carbon stocks decreasing in the case of monoculture management. Results also documented that management scenario D with straw incorporation and intercrops represented sustainability and carbon stock increase during all modelled climate scenarios. The SOC stock at the end of the century was approximately 66 t/ha. This represents a moderate sequestration of SOC of approximately 0.09 t/ha/year.

In vitro propagation techniques particularly apply for genotypes, where classic approach fails to succeed or if it is less efficient. One of these cases is compactly growing plum cultivar ‘Dwarf’, which considerably complicates the nursery propagation due to its shortened internodes. For in vitro micropropagation of this plum, we tested the Murashige and Skoog (1962) growth media with cytokinin added: 6-benzylaminopurine, thidiazurone or 2- isopentenyladenine. The highest multiplication coefficient (2.56) was achieved at 4 mg/L of 6-benzylaminopurine.

Apples are an important source of polyphenolic substances that contribute to the antioxidant activity of the fruit. Presence of apples in the diet significantly contributes to the intake of polyphenols. Apple consumption is associated with prevention of degenerative diseases. Polyphenolic profiles of apples from different regions of the Czech Republic and Poland were analyzed using high-performance liquid chromatography with diode array detection. Four phenolic substances quercitric, epicatechin, phloridzin, and chlorogenic acid were determined in selected apples samples. No statistically significant differences between the regions of the given country were determined for the varieties ‘Golden Delicious’ and ‘Idared’. Chlorogenic acid was the major polyphenol in apples from Poland and its content tended to be higher being 45.4 ± 20.2 µg/g for the ‘Golden Delicious’ and 74.1 ± 2.6 µg/g for the ‘Idared’ varieties, while in the Czech Republic it was 34.2 ± 14.0, respectively 44.3 ± 21.3 µg/g. In contrast, Czech apples contained more epicatechin and quercitrin in these varieties.

Prunus pumila L., the dwarf sand plum (also named sand cherry), is a North American shrub with edible fruit. It is not yet widely known in Central Europe, but it has the potential to become of interest to growers thanks to its adaptability and drought tolerance. Apart from the fruit processing, the value of this species lies in its applicability as a rootstock for apricot and peach. Our work aimed at the micropropagation techniques for this species. We used the Murashige and Skoog growth medium with selected auxins and cytokinins added. In the multiplication phase, thidiazuron proved itself to be efficient in the concentration 1 or 2 mg/L. For the rooting induction, satisfactory results were obtained when indole-3-butyric acid was used in the concentration 5 mg/L.

Virus diseases damage plants in varying degrees, affect their development and can cause economic damage by reducing yields and the quality of plant products. Sanitation procedures against plant viruses are generally developed in two basic approaches - in vitro chemotherapy or thermotherapy. In comparison with thermotherapy, chemotherapy eliminates the need for technically and financially demanding equipment to achieve and maintain high temperatures for a long time. Chemotherapy is performed using chemicals with virostatic effects that inhibit multiplication of virus. The chemical – antivirotic compound is added to in vitro culture media using antibacterial micro-filters after autoclaving. Chemotherapy of plants is carried out in laboratory cultivation room in standard growing temperature from 21 to 24 °C in the number of dozens of repetitions on several square meters, which streamlines the whole process. This work describes the possibilities of using selected chemotherapy agents against virus diseases of fruit crops.

Plum pox virus (PPV) is of the most important and harmful virus disease of plums, apricots, and peaches. Previous research has shown the non-transmissibility of PPV by aphids to genetically modified ’HoneySweet’ plum cultivar and to PK clone of BN4Kr myrobalan rootstock. In our experiments, the hypothesis was verified that non-transmissibility of PPV by aphids also exists in more resistant non-transgenic cultivars of plum or apricot. Therefore, relatively resistant cultivars of plum ’Gabrovská’, ’Anna Späth’, ’Althanova renklóda’ and apricot ’Harcot’, ’Hargrand’, ’Krajová raná’, grafted on the aphid transmission resistant myrobalan rootstock PK, were tested in pilot plantation conditions. None of the tested plum and apricot cultivars were naturally infected with PPV by aphid transmission. However, during monitoring in particular years, the successive die back of the ’Krajová’ and ’Hargrand’ apricot trees was noted, probably due to the poor affinity with PK myrobalan. Monitoring will continue in the following years.

Apples have long been the most important fruit commodity in the Czech Republic, but their domestic production is threatened by imports of cheaper foreign apples. However, taking into account the fact that consumers often prefer domestic products and are willing to pay extra for them, incorrect labelling of the country of origin (socalled "false geographicality") is an unavoidable risk. From an analytical point of view, however, the control of geographical origin is a difficult task and the procedures published so far have their limitations. The aim of this pilot study was to verify the potential of a new, as yet untested strategy for detecting apples with incorrectly stated geographical origin. Non-target analysis of the epicuticular layer of fruits was performed using the UHPLC-HRMS/MS technique. Obtained data ("chemical fingerprints") were analysed using advanced statistical methods. The results showed significant differences in the spectrum of epicuticular waxes of different apple cultivars and indicated the need to process a larger set of exactly characterized fruits, which will allow the construction of a diagnostic model to determine geographical origin.

The diversity of three non-coding plastid DNA loci (trnL/trnF spacer, trnV/16SrRNA spacer, trnL/trnL intron) was assessed in 16 Solanum L. species (135 individuals). Polymorphisms were detected by denaturing gradient gel electrophoresis (DGGE) and verified by direct sequencing. No intraspecific diversity and only poor interspecific diversity was detected. Unique S. mochiquense Ochoa specific length polymorphism at the trnL/trnL locus represented by duplication of an 18 bp segment was discovered. The detected DGGE interspecific trnL/trnF locus polymorphism did not specifically associate with single point mutations in the sequence confirmed by sequencing. The DGGE method was found to be a simple and cheap pre-exploring tool for mutation detection in compared DNA regions. Some identified polymorphisms can be used in the management of genetic resources.

Sweet cherry is a vegetatively propagated, perennial plant with high level of heterozygosity and ancient breeding history. Therefore, it is necessary to keep, conserve and evaluate known genetic resources for fu- ture breeding programs and fruit production stability. In present, the utilization of DNA molecular genetic analyses is the best suitable method for evaluation of individual accessions, thus we eliminated duplications and characterized the genetic relationships. In our work, we used PCR primer combinations for 19 SSR and 2 EST-SSR loci for analyses of 123 current, old and local sweet cherry cultivars from Czech genetic resources of Research and Breeding Institute of Pomology in Holovousy. In total, 115 polymorphic fragments were amplified, which we used for hierarchical cluster analysis of genetic variability. The result dendrograms were divided into three main clusters and ten subgroups. Clustering corresponded to genealogical and geobotanical characteristics of individual accessions as breeding history of several known accessions.

The suitability of different in vitro artificial inoculation methods for testing apple resistance to fire blight was evaluated. Six proliferation MS media containing BAP, TDZ or 2iP were tested to determine favourable conditions for shoot development. Out of the tested cytokinins, only media with BAP proved to be useful for all tested cultivars for artificial inoculation with Erwinia amylovora. Out of three tested inoculation methods, removal of 3 mm of the shoot apex with scissors and transfer of bacterial suspension by pipette (method 1) appeared to be the most suitable technique. This method enabled the determination of susceptibility of two cultivars due to the different speed of fire blight symptom development.

In order to find an effective elimination method of Blueberry red ringspot virus (BRRV), shoot tips of 2-3 mm size originating from buds of highbush blueberry cv. Darrow naturally infected by BRRV and collected in winter months were regenerated and multiplied on woody-plant medium (WPM) with 1.5 mg/l zeatin and 20 g/l sucrose. Developed shoots tested negative by polymerase chain reaction (PCR) for BRRV were transferred onto a rooting medium consisting of WPM supplemented with 1 mg/l indole-3-butyric acid. Rooting plants were transferred into soil and tested twice by PCR 6 months apart. Ninety per cent eradication of BRRV was achieved while isolating shoot tips, multiplying them in one vegetative generation, and regenerating whole 50-60 cm high plants within 30 months. All plants developed rich fruits after their overwintering in a cold greenhouse and were tested BRRV negative in summer 2013.

The epidemiology of potato late blight (Phytophthora infestans) was observed over the three-years with 110 potato varieties from various maturity groups treated or not treated with fungicides. The determined severity values were transformed into AUDPC coefficients characterizing rate of disease spreading across the crop in connection with varietal characteristics, fungicide application and year effects. The analysis of the pathogen population for the distribution of races virulent to usually used resistance genes indicated non-efficiency of these genes; resistance could only be increased by breeding for polygenically determined horizontal resistance. There were important yearly variations observed for the epidemiology of P. infestans. A correlation was detected between increasing AUDPC value and yield reduction in both fungicide treated and non-treated variants. AUDPC value of the treated variant is to a certain extent positively correlated with the value of the non-treated variant. However, particular interaction between potato genotype and applied fungicide program was shown, which could positively or negatively affect disease course in dependence on the variety.

Marker assisted selection (MAS) in potato breeding is the most developing area at present time. Methods of DNA markers are developed in all top world potato research institutes and universities oriented on plant production. This paper presents results obtained from the testing of gene resources encompassing different resistance genes against Phytophthora infestans potentially exploitable for Czech potato breeding. Three different DNA markers were studied that are linked to R1 locus in the potato chromosome V operating as a resistance against some races of P. infestans. Markering capability and frequencies of these markers was evaluated with respect to their usage in practical Czech plant breeding that has vital importance in finding the tools as a prerequisite for creating new varieties efficiently.

The skin colour of 21 varieties was assessed on a molecular level. Four varieties had yellow skin colour with the genotype constitution a1a1, a1a2 or a2a2. Seventeen varieties had dominant red colour. Homozygous A1A1 constitution was present in 7 varieties, and heterozygous constitution A1a1 or A1a2 was found in the rest of the assessed varieties. The S-alleles controlled the incompatibility system of the pistil. Their detection is possible by means of the PCR method on the basis of allele specific primers. Six S-alleles (S1, S2, S3, S5, S7 and S9) were studied in the same collection of 21 diploid Czech varieties. This paper brings new findings on S-allele characterization, because the Czech varieties have not yet been studied on a molecular level. Both types of S-allele were found in 12 varieties. Only one type of S-allele was described in 9 varieties. Simultaneously, the presence of the Vf gene was screened in the collection of 21 Czech apple varieties. Ten varieties with a field resistance against the scab had a heterozygous constitution of the Vf gene. All 11 susceptible varieties were recessive homozygous vfvf.

The growing of resistant apple varieties against the scab, impacts the Venturia inaequalis CKE. races development that can overcome the resistance. For this reason the main breeders object is to cumulate the different genetic mechanisms of resistance against this disease. Presented in this paper is the first genetic study of monosporic isolates in the Czech Republic. By means of RAPD and UPGMA methods which characterised the variability of 10 monosporic isolates from different localities and apple varieties. The monosporic isolate derived from the resistant genotype (Vf gene) proved a 79% genetic similarity with the isolate derived from sensitive variety Top Red. The genetic similarity of other isolates did not prove the dependence either on a locality or a host variety. The Vf and Vm genes accumulation in apple germplasm by means of specific PCR markers was studied. It was confirmed that Vf gene donors are always heterozygous. Concurrently it was statistically confirmed that the donor of Vm gene (OR-45-T-132) is heterozygous, too. The accumulation of Vf and Vm major genes against the scab was validated in 25% of seedlings of the cross.

CAPS (Cleaved Amplified Polymorphic Sequence) method and standard infection tests were used for the study of tomatoes (Lycopersicon esculentum L.) resistance against the root-knot nematode (Meloidogyne incognita Kofoit and White). The CAPS method was used to determine genotypic constitution of Mi gene in ten Czech and four foreign varieties of tomatoes. Similarly were verified one hundred and twenty individuals of F2 segregated progeny of Nema variety and the same number of F2 progeny of Petopride variety. A comparison of results of infection test with results of molecular-genetic analyse of DNA showed 100% congruence in detection resistant (susceptible respectively) genotypes. Result of 2 test confirmed in the level of mathematical expectation P (0.5, 0.7) congruence between actually obtained and theoretical segregation ratios. The CAPS method can be recommended for fast and precise determination of resistance or susceptibility of tomato plants against the root-knot nematodes. The goal of the method is the possibility of detection of genotypic constitution of Mi gene that can significantly accelerate the process of creation of new resistant varieties.

Potato cyst nematodes (PCN) are the big problem in worldwide planting of potatoes and another Solanaceous plants. Identification of individual pathotypes according to international scheme is very demanding but a very important part of the phytosanitary process to control these pests. Molecular genetic identification of different plant and animal species or individuals is a very interesting way at the present time and let's hope that it will be important in future. This report presents results of the RAPD study of nine different real PCN populations. There were five Globodera rostochiensis populations and four G. pallida populations. Pathotypes Ro2, Ro2/3, Ro4, Ro5, Pa2 and Pa3 were from European populations; population Ro1 and X were of Czech provenance. Genetics variable of these populations was described by a set of six decameric primers (OPA 07, OPG 03, OPG 05, OPG 08, OPG 10 and OPG 13). Genetic dissimilarity was by Gel Manager for Windows evaluated. Detectable differences behind all populations were found and the dendrogram was compiled. The unknown population X was sorted into group of Globodera pallida species subgroup of Pa2 consequently.

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.

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.

Four on-farm plantations (KRNAP Vrchlabí, the Orchard of Reconciliation in Neratov, Podyjí National Park, and Šumava National Park) were successfully established in a traditional form, with large orchard trees on seedling rootstocks. Certain accessions (cultivars) for on-farm conservation in the given locality were selected, according to the incidence and presentation of genotypes in these particular areas. This information was obtained by localization of fruit trees in situ and the determination of certain cultivars. Nursery stock production for onfarm plantations is described. Because of the longevity of the plantation, seedling rootstocks were used for the production of planting materials for the on-farm plantations. Techniques of on-farm plantation establishment and orchard management are stated within the paper. Four established on-farm plantations have ensured the long-term preservation of landraces in their original areas.

In situ conservation is considered as conservation of wild biota in the natural habitat (locality). The authors extend the term to cultivated fruit species naturalised in the landscape, such as occasional spontaneous seedlings, and planted material such as old solitary trees among fields, old groves, avenues (country lanes), wind-breaks, and abandoned remnants of orchards. In situ conservation is also used to mark unique materials during collecting expeditions, before they will be taken as ex situ or proclaimed as permanent in situ. Important landraces found within 12 regions of the Czech Republic were registered, evaluated, and in situ localised by Global Positioning System (GPS). The following accessions were marked for in-situ conservation: apple (401), sweet cherry (263), pear (91), plum (42), sour cherry (27), and berry fruits (18).

Nowadays a number of lignans (arctigenin, matairesinol, pinoresinol and phillygenin) have come to the fore in research due to their various biological activities. In this paper the accumulation of these constituents in leaf extracts of Forsythia plants (F. intermedia, F. ovata 'Robusta’ and `Tetragold', F. suspensa, F. viridissima) was quantified using a new isolation method, supercritical CO2 fluid extraction. The total phenolic and flavonoid contents, the antioxidant capacity and the aglycone lignan profile were determined in leaf extracts of Forsythia species. Within the phenols, the flavonoids were only present in small quantities, but the amount of aglycone lignans was extremely high. F. ovata `Robusta' had the highest total lignan content (103.8 mg/g) of all the Forsythia species. The main lignan in this species is arctigenin, which normally makes up about 60% of the total lignan content, but in the case of F. ovata `Robusta' this value was 96.1%. Since this arctigenin content is outstanding compared to that of other Forsythia species, it could be promising to develop a fermentation technology for the production of this natural compound.