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V pěstitelských systémech zvyšuje len olejný biodiverzitu zemědělské výroby a nezatěžuje další rostlinnou produkci. Jedním z požadavků pro řádně založené porosty je kvalitní a zdravé osivo, kterému předchází úspěšná semenářská produkce. Z8kladem efektivní produkce je dodržení základních pěstitelských parametrů a potřeb olejného lnu.d.
Od roku 2000 probíhá v ČR testování nových genotypů ozimé řepky v mezistaničních předzkouškách výkonu na vybraných stanovištích. Byly posuzovány zejména hospodářské vlastnosti včetně vyhodnocení výnosu a odolnosti vůči významným houbovým patogenům, které představuje Leptosphaeria maculas / L. biglobosa (původce fomové hniloby brukvovitých) a Sclerotinia sclerotiorum (původce bílé hniloby řepky). Nové genotypy ozimé řepky pocházely ze šlechtitelských stanic v Opavě, Chlumci nad Cidlinou a ve Slapech a byly testovány na vybraných lokalitách v Šumperku, Chlumci nad Cidlinou a v Kujavách. V letech 2010 až 2012 bylo každoročně testováno na 50 nových materiálů. Získané výsledky potvrdily šlechtění odolnějších materiálů vůči sledovaným houbovým patogenům při dosažení stabilního výnosu. Původ genotypů průkazně neovlivnil získané výsledky jejich odolnosti, přesto nejvyšší průměrné hodnoty odolnosti vůči vybraným patogenům před sklizní byly pozorovány u genotypů ze šlechtitelské stanice Opava a Chlumec nad Cidlinou.
Příspěvek reaguje na změny hospodářského typu u lnu setého Linum usitatissimum L. pěstovaného v České republice. Pěstování a šlechtění přadného lnu bylo v České republice prakticky ukončeno a veškerá pozornost se v současnosti zaměřuje na šlechtění a pěstování olejného lnu. Pro zvýšení užitkovosti olejného lnu jsou v příspěvku prezentovány a diskutovány různé směry šlechtění s cílem diferenciace konečného produktu pro vybranou cílovou skupinu uživatelů.
Changes in genetic diversity of peas bred in the Czech Republic and in former Czechoslovakia since the mid-20(th) century were analysed using 38 molecular marker loci, including retrotransposons and microsatellites, differentiating a total of 84 alleles. Both marker types were comparably effective in revealing the genetic diversity, with a high correlation (r = 0.81), although the pairwise genetic distances of each marker type differed. In total, 175 accessions, selected from the Czech pea gene bank collection and representing the pea cultivars collected or bred in the country, were divided into three groups according to their date of sampling or variety registration. The first group contained 70 old cultivars and landraces collected prior to 1961. The second group contained 46 cultivars released from 1961 to 1980. The third group contained 59 cultivars released between 1981 and 2004. In spite of the decline in several diversity measures, differences in allele frequencies and even allele loss in three microsatellite loci were recorded over the 70-year period, while these differences between the groups were not statistically significant. In addition, genetic heterogeneity was detected in 29 accessions (15%). This indicates that although no genetic erosion could be observed since then, it is important to monitor the genetic diversity, furthermore it highlights the vital role of germplasm collections for the crop diversity conservation.
Since 2008 the airraid of Leptosphaeria maculans/L. biglobosa ascospores is pursued within forecasting of the occurrence of the Phoma stem canker in the Czech Republic on five selected localities. Pathogen ascospores are captured by the spore traps in every period from sowing oilseed rape till mid-November. Ascospores airraid was compared with the course of weather conditions on individual sites. The Phoma stem canker incidence is strongly influenced by weather conditions and source of infection. Although is not in recent years strong incidence of disease in winter oilseed rape growths, the prognosis of the risk of infection is very important. Ascospores airraid was recorded at monitored sites in varying degrees, while depending on the weather factors and the influence of locality. In areas with an increased incidence of Phoma stem canker (Šumperk and Opava regions) mutual correlations were observed between selected weather factors and amount of released ascospores or disease incidence in the crop growth before harvest.
The crossing was carried out in 2002. The selection of individual plants was repeated every year from the F2 generation. Yield tests were performed since the F4 generation, the 2 10 m2 yield trials. Breeding line SM 441/02 was included in yield trials in the green maturity (technological maturity) and was sown (sowing density: 1,1 mil of germinating seeds per hectare) with standard varieties. The homogenization process usually takes 3 - 4 years, morphologically different and less efficient lines were excluded during the process. When needed, the reselections from yield trials were carried out. Selections of resistant plants (from F2 generation) to the powdery mildew (Erysiphe pisi) were traditionally done in the field or greenhouse after artificial inoculation with Erysiphe pisi. Selections aimed at obtaining field resistance to foot-rot complex diseases (the most important diseases) in peas were carried out practically since F3 generation using tests in infected soil. The breeding lines were tested since F4 - F6 generation, the repeated tests for resistance to fusarium race 1 and race 2 were done in a the laboratory conditions. The analyses of starch, amylose and resistant starch content were carried out in all lines selected in yield trials. Chlorophyll and carotenoids (lutein and β-carotene) were observed.
The distinctness of, and overlap between, pea genotypes held in several Pisum germplasm collections has been used to determine their relatedness and to test previous ideas about the genetic diversity of Pisum. Our characterisation of genetic diversity among 4,538 Pisum accessions held in 7 European Genebanks has identified sources of novel genetic variation, and both reinforces and refines previous interpretations of the overall structure of genetic diversity in Pisum. Molecular marker analysis was based upon the presence/absence of polymorphism of retrotransposon insertions scored by a high-throughput microarray and SSAP approaches. We conclude that the diversity of Pisum constitutes a broad continuum, with graded differentiation into sub-populations which display various degrees of distinctness. The most distinct genetic groups correspond to the named taxa while the cultivars and landraces of Pisum sativum can be divided into two broad types, one of which is strongly enriched for modern cultivars. The addition of germplasm sets from six European Genebanks, chosen to represent high diversity, to a single collection previously studied with these markers resulted in modest additions to the overall diversity observed, suggesting that the great majority of the total genetic diversity collected for the Pisum genus has now been described. Two interesting sources of novel genetic variation have been identified. Finally, we have proposed reference sets of core accessions with a range of sample sizes to represent Pisum diversity for the future study and exploitation by researchers and breeders.
The chapter is dealing with flax and linseed (Linum usitatissimum L.) methods of breeding. At the beginning of the chapter the survey of flax growing in Europe and in the world is presented followed by description of the work with flax and linseed genetic resources, International Flax Database, conventional and unconventional methods of breeding. The chapter is closed with the Internet link to the European catalogue with flax and linseed varieties.
The use of digital image analysis (DIA) for characterization of varieties is much quicker and easier than conventional morphometric methods. This non-destructive, highly effective technique employs an inexpensive imaging system, which allows image acquisition, image processing and feature extraction. In this study digital image analysis was used for the detection of assumed duplicates in the germplasm of a flax/linseed collection, based on petal measurements. A group of 131 different flax/linseed varieties was used in tests for defining key features. The aim of the investigation was to determine if petal size could be used to distinguish compared accessions (doubles, triples, quadruples). The linear regression model used for feature assessment enabled successful identification of the dissimilarity or similarity among tested accessions. The position and distance of accessions in groups of clusters were obtained by hierarchical cluster analysis. Duplicates in the germplasm of the flax collection were confirmed by non-significant statistical differences between tested accessions. Based on the passport descriptor ACCENAME analysis it was revealed that out of 97 evaluated couples 81(83.5%) showed a significant difference in petal size, resulting in the conclusion that they are not real duplicates. Only 10 couples (10.3%) showed non-significant differences in petal size and shape could be considered as real duplicates. Six couples (6.2%) remained undetermined, as it was not possible to make a clear distinction using the above mentioned methods, due to the influence of year or other external factors. Image analysis followed by hierarchical cluster analysis was recommended as one of the methods useful for the characterization and rationalization of a germplasm collection. (C) 2011 Elsevier B.V. All rights reserved.
Metoda využití molekulárních markerů pro diagnostiku houbových chorob řepky byla optimalizována na izolátech hub Verticillium dahliae, Verticillium longisporum a Leptosphaeria maculans. Byly nalezeny markery umožňující spolehlivou identifikaci a odlišení těchto patogenů. Pomocí těchto markerů bylo otestováno 54 vzorků rostlin ozimé řepky s různě výraznými příznaky houbových chorob. U velké části vzorků bylo prokázáno napadení patogenem Leptosphaeria maculans, byly nalezeny různé rasy tohoto houbového patogena. Napadení patogenem Verticillium spp. bylo prokázáno pouze ve dvou případech.