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Impact of the type of storage on seed germination of endangered sharp leaved pondweed (Potamogeton acutifolius) and common curled pondweed (Potamogeton crispus)
POSPÍŠILOVÁ, Radana
This work mainly focuses on the issue of seed germination, restoration of turion growth, and their preservation in two Potamogeton species. Particularly speaking about, receding in Czech flora Potamogeton acutifolius (sharp-leaved pondweed) and, in many parts of the word invasive, Potamogeton crispus (curly-leaf pondweed). The introductory chapters contain descriptions of these two species, the germination and turion growth issue of some other temperate zone aquatic plants and turion characteristics. Then the study deals with the experiment itself, including progress of work and the description of individual tests, the results of which are statistically evaluated. Finally, conclusions are drawn from the obtained data.
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Alleopathic potential of plants of hemp (\kur{Cannabis sativa})
KLEJNA, Tomáš
The aim of the work was to compare the effects of germinating seeds, fresh flowers and aqueous extracts from fresh and dried parts (leaves and flowers) of hemp plants on seed germination of model crops - wheat, oats, white mustard, narrow-leaved lupin, white clover and lettuce in laboratory conditions. After 3 days of germination, the total length of the roots and shoots was measured. In individual variants, the relative allelopathic effect, average germination and statistical significance were evaluated. The effect of the distance of germinating seeds from samples of hemp material was also monitored. The effect of germinating hemp seeds, with the exception of oats, has not proved to be very significant. The effect of parts and aqueous extracts of hemp plants was as follows: -statistically significant inhibitory effect of the aqueous extract of the dried flower on the germination of wheat -statistically significant inhibitory effect of fresh flowers and extract from dried leaves of flowering plants on the germination of oats, there is also a statistically significant effect of the distance of germinating seeds from the sample of hemp material -statistically significant inhibitory effect of fresh flowers and extracts of fresh and dried leaves on the germination of white mustard, there is also an effect on average germination values -practically no or stimulating effect on the germination of legumes: narrow-leaved lupins and white clover -statistically significant inhibitory effect of fresh flowers and fresh leaf extract on lettuce germination, again with an effect on average germination
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Interactions of initially mycoheterotrophic plants with environment
Figura, Tomáš ; Ponert, Jan (advisor) ; Kolařík, Miroslav (referee) ; Janoušková, Martina (referee)
Initially mycoheterotrophic plants have recently been declining in the wild, even without apparent causes. They are affected by a number of biotic and abiotic factors. The aim of this work is to investigate how selected factors, such as nitrate or symbiotic fungi, may influence their distribution in nature. In particular, the work applies in vitro experiments, molecular determination of fungal symbionts and stable isotope analyses. It describes both the effects of abiotic factor, specifically nitrate, and biotic interactions of initially mycoheterotrophic plants with fungal symbionts. The inhibition of germination by extremely low concentrations of nitrate in asymbiotic in vitro cultures was observed in several orchid species. The degree of sensitivity of each species to nitrate corresponds with the nitrate content of the soil and the nutrient availability requirements of the species according to Ellenberg indicator values. The inhibitory effect of nitrate on orchid germination was also observed in symbiotic in vitro cultures. Out of five tested fungal strains, only one Ceratobasidium was capable of eliminating the inhibitory effect of nitrate. Furthermore, the work reveals that green mixotrophic orchids use photosynthates to nourish the aboveground parts, whereas the belowground parts are...
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Effect of seed treatment on the germination of different provenances of Dodonaea angustifolia; a recommendation for degraded land restoration through direct seeding
Petrovičová, Lucia
In Jara Jinesa nursery site in Ethiopia near Awassa city an experiment on germination rates of Dodonaea angustifolia was realized in 2015. To examine this rate, three different provenaces were evaluated for four different seed treatment methods and compared with control sample of untreated seeds. Hot water treatment at both time intervals prove significantly positive effect on seed germination. After this treatment seeds germination rate reached from 70 to 100 %. The positive effect of seeds soaking in cold water has not been recorded, in some cases even reduced germination over any untreated seed. Within 3 to 6 days of sowing, especially in warm water treated seeds, the number of germinated seeds increases steeply. The impact of provenance is evident especially in the various time span optimization, since each provenance is adapted to specific environmental conditions. Treating seeds with warm water before sowing increased the uniformity of seedlings, thereby increased the quality of seed production without significant technological equipment and financial costs
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Klíčivost semen Dracaena cinnabari v kontrolovaných podmínkách
Bauerová, Lucie
Bachelor thesis is focused on germinability of Dracaena cinnabari seeds under different temperature conditions, in addition with seeds collected in different ways and from different localities as well. At first, a germination process is described and in addition the factors that have a substantial effect on seed germination and germinability. In another part of the work the methods that are used for germinability testing under laboratory conditions are presented. And in the last part of this section there are summarized current informations about germinability of D. cinnabari seeds and other species of Dracaena genus and related genus Sansevieria. In the practical part, four seed sections were used. These sections were collected either directly from the fruits of a cut panicle or from the ground, and moreover they were from different localities differing in altitude. The sections were named as PL, SB, NN, PE. Seeds were tested in Petri dishes under three different temperatures - 22, 26 and 30 °C, where 4 replicates of 25 seeds of each section were used. The highest germinability was achieved at 26 °C and 30 °C (of 2nd attempt) with germinability 84,6 % and 82,5 % respectively. In addition, a germination energy was calculated for each test. Seeds showed the highest germination energy at 26 °C. The results show a higher germinability of D. cinnabari seeds particularly at higher temperatures. The germinability was evaluated also for individual seed sections and because the sections were collected in different ways and from different localities, the influence of both of these factors was assessed on resulting seed germinability. Finally is concluded that this species probably has a relatively high potential ability of natural regeneration, implying that there is also a potential for regeneration of populations by an artificial way.
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Natural regeneration of Norway spruce in mountain forests and at disturbed plots
Urbanová, Renáta ; Hadincová, Věroslava (advisor) ; Brůna, Josef (referee)
The natural regeneration of Picea abies in undisturbed mountain spruce forests as well as in disturbed areas formed by windstorms and overgrowth of bark beetles, especially spruce bark beetle (Ips typographus), takes place primarily through seed germination from a transitional soil seed bank. The quality of the soil seed bank depends on the amount of seeds available, which varies significantly throughout years, and on environment conditions. Interannual changes in the amount of seeds produced are caused by the irregular occurrence of seed years, which reflects weather changes in the context of ongoing climate change. Increased average air temperature and unevenly distributed rainfalls throughout the year have a positive effect on the spruce phenology, seed abundance and quality and results in increasing frequency of seed years. The large amount of seeds during seed years induces increased abundance of granivores for which the seeds are the source of nutrients and environment for their development. Seed predators of invertebrates and, small vertebrates groups and fungal pathogens significantly reduce the proportion of seeds needed for spruce natural regeneration. This bachelor thesis summarizes up to now knowledge explaining mechanisms and interactions associated with the soil seed bank of Picea...
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Use of seed germination test in the inquiry-based science education at primary and lower secondary schools
LANDOVÁ, Tereza
This diploma thesis discusses the possibilities of diversifying the teaching on the issue of germination in the form of worksheets as well as possibility of using germination tests in the inquiry-based teaching of biology at elementary schools and lower secondary schools. The readers are introduced into the general issues regarding seed development, construction and germination. It then deals with iquiry-based teaching, which is one of the most used methods in biology education in recent years. Worksheets created for this purpose are therefore validated through teaching practice and subsequently processed and evaluated. The paper discusses whether germination is a suitable biological material for inquiry-based teaching and also whether these worksheets can be recommended as a didactic teaching material for the development of skills and theoretical knowledge of germination.
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Stanovení produkce semen a jejich klíčivosti u vybraných plevelných druhů z čeledi Apiaceae
Bobrovská, Pavla
Diploma thesis was focused on the determination of seed production and their germination of selected species in the Apiaceae family. Selected species were common hogweed (Heracleum sphondylium) and cow parsley (Anthriscus sylvestris). Further was conducted determination weight of thousand seeds of both species and at common hogweed was also determined by the number of seeds containing endosperms, thus seeds potentially capable of germination. Before determining the germination the seeds were stored at different temperature conditions for the long term. Under laboratory conditions was detected in the case of common hogweed very low germination and in the case of cow parsley zero germination. The average seed production per plant was at 888 hogweed seeds and at cow parsley 1 194 seeds. The average weight thousand of seeds was at common hogweed 2,79 grams and at cow parsley 2,12 grams. The endosperms were detected in less than half of the examined seed at each station.
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