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Hodnocení vybraných znaků perspektivních odrůd broskvoní
Horsáková, Jana
Dissertation work deals with the evaluation of the selected characters of promising peach varieties grown in the genepool collection and pilot testing block. The evaluation took place between year 2011 to 2013. The work can be divided into three thematical units. The first part deals with the health condition, specifically monitoring of the occurrence of European stone fruit yellows phytoplasma (ESFY) and the plum pox virus (PPV). The second part focuses on the physiological events occurring in flower buds (dormancy, microsporogenesis, frost resistance) and the third unit deals with pomological characteristics of varieties and the economic evaluation of varieties which are already introduced in the commercial cultivation. In the literature section the origin and the spread, world production of peaches and the current situation in the Czech Republic are descibed and a chapter about peach breeding is included as well. Further, chapters characterizing dormancy, microsporogenesis and frost hardiness are described in the work. Literature section also includes content substances and health-promoting substances in peach fruit. The last chapter describes the diseases causing economically significant losses in peaches. In the experimental part the incidence and symptoms of phytoplasma ESFY and synergism between PPV and ESFY was evaluated. The effect of the PPV infection on content of the total polyphenols and the antioxidant activity of fruits was investigated. Further, the termination of dormancy, microsporogenesis and frost resistance of flower buds was evaluated. Significant part of work was the pomological evaluation of selected varieties from genepool collection and evaluation of varieties in pilot testing block conditions. The results show that in peach orchards trees infected by phytoplasma ESFY show various symptoms of the disease which depend on host genotype. Synergism between Plum pox virus (PPV) and European stone fruit yellows phytoplasma (ESFY) has not been confirmed. PPV infection results in increased amount of the antioxidant activity and total polyphenols in peach fruits.Varieties can be divided into 3 groups by the term of termination of endogenous dormancy, paticulary, varieties with early termination, varieties with medium termination and varieties with late termination of dormancy. Evaluated varieties differ, either, in duration and date of occurence of phases of microsporogenesis. The process of dormancy and microsporogenesis of individual varieties is different and is influenced by the weather conditions of the year. There are differences in frost resistance between peach varieties. The highest degree of frost hardiness was set by the 'Lesiberian'. Studied peach varieties show differences in pomological, biological and economic characters. From the evaluated group of varieties the promising are 'Venus', 'Fantasia', 'Fidelia', 'Neve' and 'W 14', where the highest assessment had the variety 'Venus'. Based on evaluation of peach varieties grown in commercial orchards the best variety was 'Symphonie', which achieved consistently high yields and is characterized by good health. 'Fidelia' and 'Orion' were chosen as a mediumly suitable varieties for commercial orchards.
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Genetická determinance dormance druhu Prunus armeniaca (L.)
Čechová, Jana
As achieving higher frost resistance is one of the apricot breeding goals in the Czech Republic, it is important to obtain a deeper understanding of the genetic background of the exit from endogenous dormancy for apricot flower buds. The reason is that frost resistance of flower buds is significantly reduced after exit from endogenous dormancy. The aim of this work was to contribute to the understanding of the process of exit of various plant tissues from dormancy, as the problem is very complex and containing a number of physiological processes that are controlled by the function and regulation of many various substances and corresponding genes. The time of exit of flower buds from endogenous dormancy was established by counting of flowering buds on sampled twigs after their transport to laboratory conditions. Furthermore, the production of ethylene, ethane, and CO2 was monitored for sampled twigs with flower and leaf buds. Other physiological parameters monitored during the course of this study were the level of abscisic acid in flower buds and their weigh during the sampling close to the period of exit from endogenous dormancy. An analysis of transcriptome using the cDNA-AFLP method was carried out on four apricot variants ('Sundrop', SEO, 'Vestra' a 'Betinka') to achieve a deeper understanding of the genetic background of exit of flower buds from endogenous dormancy. The transcription profiles obtained from this experiment were evaluated for changes in the expression profiles and fragments of genes with modified expression during the monitored period were sequenced identified. Obtained sequences were compared with sequences in electronic databases (NCBI and TIGR). The results of this comparison led to the identification of a number of the sequenced genes. The results of this study confirmed the suitability of use of the cDNA-AFLP method for the identification of gene candidates and getting a preliminary picture of the main molecular mechanisms taking place during the time of exit of flower buds from endogenous dormancy. The suitability of the used procedure was confirmed by the match between the genes identified from the sequencing and genes already described in the literature as being linked to the exit of plants from endogenous dormancy (e.g. gene coding for acquaporin, GTP-binding proteins, elongation factor 1 alpha, ubiquitin, and xyloglucan endotransglycosylase hydrolase). Measurements of concentration of selected substances during exit from endogenous dormancy do not allow definite conclusions about their influence on this process. On the other hand were identified several genes that might be candidates for markers identifying the output timing of endogenous dormancy of buds and provide a good starting point for further scientific research in this field.
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Mrazuodolnost ovocných dřevin
Prudil, Jakub
This bachelor thesis desribes principles of dormancy and frost hardiness of fruit trees; significant historical frost calamities in the Czech Republic; frost effects on fruit trees; relationship of phenophases and mikrophenophases from the perspective of evolution of the frost hardiness of fruit trees; the possibilities of protection against a late spring frosts and cryopreservation as a positive use of the effects of frost.
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Mechanisms that control physiological seed dormancy
Řezková, Natálie ; Ponert, Jan (advisor) ; Vosolsobě, Stanislav (referee)
Physiological dormancy is an important developmental trait ensuring that seed does not germinate when the environmental factors are appropriate only temporary. The transition from seed dormancy to germination is regulated by a large number of factors and the phytohormone abscisic acid (ABA) plays a crucial role. Enhanced response to ABA and its biosynthesis is a key mechanism in dormancy induction and maintenance. ABA interacts antagonistically with gibberellins (GAs). Therefore GA biosynthesis and ABA catabolism are positive germination regulators. However, other phytohormones are also involved in the regulation of dormancy and germination. The most studied is ethylene which supports germination similarly to GA. Numerous factors affect dormancy at molecular level, namely chromatin remodeling, gene products that function only in dormancy regulation [e.g. DELAY OF GERMINATION 1 (DOG1)] or gene products that mediate seed response to environmental factors. The dormancy, its induction, depth and release, is driven not only by environmental conditions affecting mature seeds, but also by conditions acting during seed maturation in a maternal plant when the primary dormancy is induced. Requirements for dormancy release and germination induction may vary considerably between species. The physiological...
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Vitality and germination juniper (\kur{Juniperus communis}) seeds
OKROUHLÁ, Ilona
The thesis focuses on the fertility and vitality of common juniper seeds (Juniperus communis). Random galbula samples from two areas were tested. Amount of seeds per one galbula were compared, seed fullness and vitality were compared via the colouring method, as well as the weight, as well as a try to cancel the dormancy using gibberelinic acid GA,, following the aim to plant more seedlings. The results were compared to seed values and to findings from other authors. If the issue of lower seed fullness and vitality is clarified, more suitable methods of juniper population proliferation and support maybe worked out.
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Seed germination and seedling recruitment of Iris sibirica depending on the type of management
HOŘEJŠÍ, Edita
This work continue on a bachelor's work which investigated production characteristics of the plant species Siberian Iris (Iris sibirica). The aims of the presented work are reproductive properties by seeds of Siberian Iris in relation to the seed germination and with various meadow managements. Seeds of Siberian Iris (collected in 2015 and 2016) were investigated in laboratory condition and at meadow near the pond Dolní Stržený (Dlouhá Lhota, of the Tábor District). Seeds were divided into groups according to 4 treatments: without intervention, scarification, thermal stratification and cold stratification. The field experiment runs from September 2016 to August 2017.The aim was to find out the most appropriate type of management (mowing, disturbance) that would promote seed germination and seedling recruitment. Results from the both experiments: a positive effect of germination after the scarification, better recruitment of seeds in square without intervention, seeds probably needs to be stored for a longer period before sowing. These results cannot be generalized, because small number of repetitions were performed. All the obtained data was discussed and recommendations for the plant management were formulated.
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Interakcia fytohormónov a vonkajšich faktorov v dormacii hľúz ľuľka zemiakového (Solanum tuberosum L.) odvodených v explantátovej kultúre
Maco, Roman
Microtubers were obtained from potato plants (Solanum tuberosum L.) cultured in vitro, they were used in following experiments. The impact of growth regulators (FLD, AgNO3, BA, ABA) was monitored in length of dormancy. The content of ABA in the budding tubers and the content of endogenous CK (BA, IP, DHZ, DHZR, Z) was determined during the dormancy as well. Production of ACC, ethylene, O2, CO2 and ethane was determined by gas chromatography. Variants containing FLD, AgNO3 and BA had a significant impact in the shortening of dormancy and stimulation the growth of buds microtubers. When they were used the occurrence of budding tubers was increased by 30-40 % over the control. Variant of ABA inhibited the growth of buds. ABA content correlated with the process of dormancy and the occurrence of budding tubers. The highest content of ABA was in variant with freshly collected dormant tubers. Concentration of various CK was dependent on the type of CK and monitored variant. Generally, It was slightly increased with occurrence of budding tubers.
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Ecophysiological relevance of extreme sensitivity of orchids to nitrates
Figura, Tomáš ; Ponert, Jan (advisor) ; Tylová, Edita (referee)
Many orchid species are seriously endangered at present. Reasons for their disappearing from natural habitats remain often unclear. Orchids depend on mycorrhizal symbiosis in nature, however only little is known about this symbiosis. Seeds of some species do not germinate in vitro, making their cultivation for scientific and rescue purposes impossible. We found that seed germination of one of such reluctant species, Pseudorchis albida, is strongly inhibited by nitrates even at extremely low concentrations. As this species prefers oligotrophic mountain meadows, nitrate-induced inhibition probably take place in natural conditions. Surprisingly, we found similar but slightly weaker inhibitory effect also in typical mesophillic species and even in slightly eutrophic ones. The sensitivity to nitrates correlates with trophy level of species canopy. This inhibitory effect of nitrates could be weakened by application of a range of growth regulators, including auxins, cytokinins and gibberellins, and also by mycorrhizal fungi. The action of nitratereductase is essential for this inhibitory effect of nitrates. Experiments with NO donors, scavengers, and NO quantification are pointing right at NO as compound which perhaps mediates nitrate inhibitory effect. Based on these results, the nitrate inhibitory...
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Analysis of biological features of Capsella bursa-pastoris (L.) Med.
Schneebergerová, Tereza ; Hamouz, Pavel (advisor) ; Holec, Josef (referee)
The aim of this bachelor thesis is to determinate selected biological characteristics of shepherd´s-purse, which have impact on the establishment and expansion of its populations in field crops. In particular, development of primary dormancy was studied and the effect of factors that influence the dormancy and germination of seeds was determined.
Shepard´s purse is an annual or biennial herb of the cabbage family, which is classified as winter annual weeds. Primarily infest the winter and spring crops, rapeseeds, potatoes or forages. It appears from lowland to foothills, so biological features of individual population can be very different. The ways of control are shallow tillage or herbicidal treatment.
After harvesting of ripe seed the first experiment was set to define the primary dormancy. Remaining seeds were stored in two different types of environment. Part of seeds was stored in the dry at 20 °C. Others seeds were stratified at 5 °C. Effect of storage conditions on primary dormancy was tested every two weeks. Seeds were germinated for
1 week in grow chamber under the influence of various factors such as different light mode, type of water and type of media for germination.
The results were processed by multiple-factor analysis of variance. Fresh seeds showed a strong primary dormancy at constant temperatures of 10 °C and 20 °C. Treatment with fluctuating temperature (20/10 °C), filter paper, drinking water and stored in dark had the highest germination rate (10.75 %). Seeds stratified at 5 °C had increase in germination in first weeks, but lost it during storage. On the other hand, seeds stored in dry at 20 °C firstly were in dormancy, but they lost it gradually during storage.
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Biology, seed characteristics and growth establishment of comfrey (\kur{Symphytum officinale }L.)
KOVÁŘOVÁ, Jaroslava
The thesis titled "Biology, seed characteristics and growth establishment of common comfrey (Symphytum officinale L.)" dealt with the evaluation methods of reproduction comfrey and evaluation of the impact of environmental conditions to the grow of comfrey. Further it dealt with germination tests and their statistical evaluation while respecting the specific work with seeds. They were evaluated seed characteristics, which are reflected in the growth of these plants arising both in soil and in a laboratory environment. Literary part gave information about biology, characteristics, morphology, prevention and regulation of comfrey even more its cultivation, nutrition of the grassland and seed characteristics, germination and dormancy. In the final section of work was monitored coverage, botanical images, representation of herbaceous species growing near comfrey. The study also discussed vernalization, size of comfrey leaves, growth and development depending on the content of nutrients (soil fertility) and water in the soil and on the number of cuts to its growth. There were designed a suitable ways of reproduction and growing of comfrey.
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