National Repository of Grey Literature 6 records found  Search took 0.01 seconds. 
Management grafiózy v infikované výsadbě jilmů v Kostelanech nad Moravou
Šleglová, Hana
The thesis deals with the topic of Dutch elm disease in infected elm trees planting in Kostelany na Moravě, presents research at the area of seed orchard. There were observed the areas with two kinds of elm trees, where one of them was affected by Duth elm disease. The protection measures to prevent the spreading of the disease were proposed by the research. The orchard was attended during two vegetative periods in the year 2010 and 2011. According to information obtained about every single elm tree have been found trees with a manifestation of possible resistance. Using the new pieces of knowledge and experience obtained during the research, the state of elm trees at the park in Lednice.
Assessment of drought response in local Scots pine ecotypes using anatomical, biochemical, and fluorescence stress markers.
Štěpánová, Kristýna ; Lhotáková, Zuzana (advisor) ; Stejskal, Jan (referee)
Global climate change and associated global warming is already a problem for temperate forest ecosystems and will continue to exacerbate the problem in the coming decades. Many species will have to adapt to a multifactorial combination of stresses, with increases in average air temperature, frequency and intensity of precipitation increasing drought episodes and drought-affected areas will enlarge. It is necessary to find ways to help the landscape cope with these intensifying phenomena. The possibility of planting suitable tree species that can manage water efficiently and survive even in periods of intense water scarcity is an option. The drought tolerance of trees is related to their phenotypic plasticity and ecotypic differentiation. Scots pine (Pinus sylvestris L.) is characterised by modest ecological demands on the environment and climate of the habitat, is phenotypically plastic and relatively drought resistant. The objectives of this study were 1) to evaluate and compare the response of different Scots pine ecotypes to drought stress due to reduced water availability using anatomical, biochemical, and fluorescence indicators of physiological status, and 2) to determine the biochemical phenotype of selected genotypes within a local Scots pine ecotype in a seed orchard in terms of...
Use of laboratory and image spectroscopy to evaluate drought resistance of Scots pine and to distinguish its ecotypes
Raasch, Filip ; Kupková, Lucie (advisor) ; Potůčková, Markéta (referee)
The aim of this study was to propose a non-destructive method for measuring Pinus sylvestris seedlings, to determine whether water stress would be evident in laboratory spectra of pines, to compare whether the response of pines would differ by ecotype, and to investigate whether two ecotypes of Pinus sylvestris could be distinguished using laboratory and image spectroscopy. For these purposes, hyperspectral images of seed orchards from August 2020 were processed and a three-month laboratory experiment was conducted, in which stress from water deficit was induced in two-year-old pine seedlings from the upland and hilly ecotypes. Spectral data were analysed using mixed statistical models, analysis of variance, principal component analysis, training of supervised pixel classifiers, vegetation indices, and linear regression. Based on the analyses, it was found that water stress can be detected in severely stressed Pinus sylvestris seedlings. The most sensitive spectral bands to water content were observed in the region between 1000-2500 nm. The initial response to water stress did not differ by ecotype, but a faster recovery was observed at the upland ecotype after the period of draught. The two Pinus sylvestris ecotypes were distinguished with high accuracy from both laboratory and image spectral...
Markers of pine physiological state in relation to genetic variability
Šafránková, Anna ; Albrechtová, Jana (advisor) ; Prášil, Ilja (referee)
Breeding of coniferous trees in the Czech Republic is undergoing an important development during last decades, especially thanks to molecular-genetic methods, which refine and simplify mapping of tree genotypes and the selection of superior genotypes. Recently, in the Czech Republic superior genotypes are selected based on forestry parameters (tree height, trunk diameter, and timber quality) what does not always correlate with the ability of a tree to resist abiotic and biotic stresses. Recently, there is an effort to include in the breeding also physiological parameters and select superior genotypes using nonspecific stress indicators, which are able to correspond better to tree fitness than the forestry growth parameters. The present thesis deals with genotypes of Scots pine (Pinus sylvestris L.) growing in seed orchards Doubrava and Silov in the Pilsen region in the Czech Republic. Seed orchards are tree plantations, which serve as a reserve of the genetically valuable reproduction material, they are parts of breeding programs. Pine needles were collected in July 2015 and analyzed for non-specific stress indicators - photosynthetic pigments, phenolics, lignin, cellulose and proline contents and leaf reflectance and fast chlorophyll fluorescence measurements. First objective of the present thesis...
Management of production populations of forest tree species utilizing methods of mathematical programing
Hořejší, Matouš ; Lstibůrek, Milan (advisor) ; Stejskal, Jan (referee)
Breeding of forest tree species is a great opportunity for the entire forestry sector to succeed in the present modern World. Genetically improved forest trees have much better growing quality and they can sustain higher stress and unfavorable climatic conditions. Efficient algorithms are necessary for optimizing and establishing seed orchards. These should optimally select clones as parents in future seed orchards. In the present thesis, we developed model, based on mathematical programming methods, which creates mix of clones with the maximum breeding value and constraints on genetic diversity.
Proposal of a new seed orchard layout assuming panmictic model
Chaloupková, Kateřina ; Lstibůrek, Milan (advisor) ; Vladimír, Vladimír (referee)
The new panmictic model of seed orchard scheme for forests trees is described in this thesis. It can be used either alone or in combination with existing designs without losing efficiency. In this case it iscombined with Minimum Inbreeding design. The establishment of seed orchards and importance of achieving panmixy and minimizing inbreeding in the population of seed orchard are described in the theoretical part. The resultant algorithm defines panmictic situation as a situation where close neighborhoods of all possible combinations of clones occur within the seed orchard grid with the same frequency. To achieve this we developed a formula for variance that is minimized as a criterion function. The algorithm has been programmed in R and it was tested for different tasks including balanced or unbalanced numbers of clones and different sizes or shapes (rectangular or non-rectangular shape) of orchard. The model is able to solve all of these situations, and it is very effective especially in the case of balanced numbers of clones. Optimal solution of the given task was often found at the first iteration. To evaluate the relative quality of resulting schemes theoretic proxy to level of maximum panmixy was defined for every specific task- the Theoretical minimum variance. The effectiveness of MI scheme combined with clonal rows was also evaluated. The result is a hybrid scheme with predefined MI clonal rows surrounded by panmictic algorithm, while close neighborhood of clonal rows was also optimized. This scheme will be used for the establishment of Abies fraseriseed orchard in North Carolina under NCSU Christmas Tree Genetics Program. Another possible modifications of the algorithm, such as the inclusion of local separation zones or assortative mating are summarized in conclusions.

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