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Interactive effects of adaptation technology, based on no-till sowing into the mulch of cover crop residues, and nitrogen nutrition on photosynthetic performance of maize under drought stress
Opoku, Emmanuel ; Holub, Petr ; Findurová, Hana ; Veselá, Barbora ; Klem, Karel
The aim of this study was to evaluate the interactive effect of adaptation technology based on no-till sowing into cover crop mulch and nitrogen nutrition on photosynthetic performance of maize under short term drought stress induced by rain-out shelters. The experiment was established in two locations in the same climatic condition but differing in soil fertility. The negative effect of drought on CO2 assimilation rate was modulated by nitrogen nutrition. However, while nitrogen nutrition led to alleviating effect at the location with higher fertility, the opposite effect was found at the site with lower fertility. Adaptation technology had only a minor impact on photosynthetic response to drought, but it generally increased CO2 assimilation rate at the site with higher soil fertility and decreased at the site with lower soil fertility. We can conclude that adaptation technology, despite of assumptions, did not significantly change the resilience of maize to drought, and probably longer use of such technology is required to improve soil water retention and thus also balanced supply of water to plants. \nAt the same time, we did not find a negative impact of adaptation technology on photosynthesis which can be related to cooler soil during maize emergence and slower mineralization, although the use of adaptation technology seems to be more effective in soils with higher fertility.
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Metody detekce houbových chorob využitelné ve fenotypování rostlin a dálkovém průzkumu
Klem, Karel ; Veselá, Barbora ; Holub, Petr ; Urban, Otmar ; Mezera, J.
Tato metodika shrnuje poznatky z porovnání tří perspektivních metod detekce houbových chorob využitelných pro dálkový průzkum a fenotypování rostlin se zaměřením na odolnost vůči chorobám. Jedná se o metody měření spektrální odrazivosti, infračerveného termálního zobrazování a modro-zelené zobrazovací fluorescence. Na příkladu napadení rostlin ozimé pšenice padlím travním, rzí plevovou a rzí pšeničnou metodika demonstruje jejich přednosti a nedostatky z pohledu detekce jednotlivých chorob, přičemž je zřejmé, že všechny tři metody jsou pro nedestruktivní detekci houbových chorob potenciálně využitelné, ale jejich praktické použití se může lišit. Testování indexů spektrální odrazivosti pro detekci napadení houbovými chorobami ukazuje především vysokou spolehlivost detekce u indexů založených na odrazivosti v red-edge a zeleném pásmu vlnových délek. Infračervené termální zobrazování prokázalo vysokou přesnost detekce u napadení padlím travním, případně rzí pšeničnou, ale již nižší u rzi plevové. Modro-zelená fluorescence i termální zobrazování představují také velmi dobrý nástroj pro vyhodnocení intensity prostorové distribuce napadení listu.
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Effect of elevated CO2 on morphological and photosynthetic parameters in two understory grass species in Beskydy Mountains
Holub, Petr ; Klem, Karel ; Urban, Otmar
We transplanted two grass species, Calamagrostis arundinacea and Luzula sylvatica, to the understory of\na 10-year-old experimental mixed forest exposed to ambient (385 μmol CO2 mol–1, AC) and elevated (700\nμmol CO2 mol–1, EC) atmospheric CO2 concentration using a glass dome facility. Effects of EC on plant\nmorphology and photosynthesis were examined after three years of treatment. We tested the hypotheses\nthat shade-tolerant species can profit from EC even at low light conditions and that relatively low accumulation\nof assimilates at such light conditions will not cause CO2-induced down-regulation of photosynthesis.\nWe expected that EC can substitute insufficient light intensities under the tree canopy and lead to both\nhigher biomass production and survival of plants in deep forest understories. The typical shade-tolerant\nspecies L. sylvatica exhibited positive acclimation under EC allowing higher light use efficiency under subsaturating\nlight intensities as compared to plants grown under AC. In contrast, C. arundinacea showed\nhigher stimulation of growth and photosynthetic rates by EC mainly under saturating light intensities at\nthe beginning of the growing season, when the forest leaf area is not fully developed and the open canopy\nallows a greater proportion of incident light to reach the understory. Our data indicate that growth and\nphysiological responses of EC plants in forest understories are species specific, differ from responses of\nsun-exposed plants, and depend on degree of shading.
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Evropská specifika umění hry na bicí nástroje: Základy přirozené hry
Zhdanovich, Anton ; MIKOLÁŠEK, Daniel (vedoucí práce) ; Holub, Petr (oponent)
Tato práce je souhrnem získaných informací a znalostí o základech, tvořících současnou tradici hry na bicí nástroje v Evropě (převážně Západní). Její hlavním cílem je podpora vývoje oboru bicí nástroje v České republice, obzvlášť ve školách, kde úroveň hry je ve stádiu rozvoje a potřebuje podporu z jiných zdrojů. Během mého magisterského studia na HAMU (2014-2017) jsem se zúčastnil řady mezinárodních akcí v daném oboru, které byly zaměřeny na vývoj mladých hudebníků mé generace po stránce hudební, technické, mentální a estetické. Informace získané ve formě zpětné vazby a komentářů u významných učitelů a interpretů v daném oboru tvoří absolutní fundament teto práce. Uvědomení principů a základů, o nichž se tu bude psát, vyžaduje již přítomnost určených hudebních a životních zkušeností, proto je tato práce určená pro věkovou kategorii od posluchačů středních odborných škol a výš.
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The effect of drought and nitrogen fertilization on the production, morphometry, and spectral characteristics of winter wheat
Trunda, Petr ; Holub, Petr ; Klem, Karel
Methods of study based on the spectral reflectance of vegetation are now commonly used in researching both natural ecosystems and field crops.The aims of this experiment were to evaluate the effect of drought and nitrogen (N) fertilization on N use efficiency in winter wheat and use the obtained spectral characteristics to assess stand heterogeneity as a potential consequence of different crop nutrition. Twelve experimental plots of winter wheat were manipulated to drought from 8 May 2013 to 12 June 2013. The effect of drought was observed in two treatments: control without fertilization (N0; 0 kg N ha−1) and N fertilization (N140; 140 kg N ha–1). Plant samples were then taken for determination of above-ground biomass and N content in dry matter. Spectral characteristics of wheat were measured in the earing phase at canopy level. The effect of drought on the morphometric parameters of winter wheat was statistically significant only on N-fertilized plots (N140). Total above-ground biomass decreased by a significant 18% in the N140 treatment as a result of the simulated drought. This decrease was reflected in statistically significant reductions of all individual plant parts (stems, leaves, spikes) in N140. Responses to drought stress were observed in many vegetation indices, particularly in NDVI, GNDVI, and WI/NDVI. The results show there are significant relationships between N content in the grain and vegetation indices. A quite marked separation was observed in the relationships between dry and ambient treatments for vegetation indices NRERI, TCARI/OSAVI, VOG2 and GM. Generally, the impact of drought increased at higher levels of N content in the grain, which corresponded with the results of morphometric analysis. Use of reflectance in the study of vegetation and field crops regarding risk assessment of mineral N leaching from soils has considerable potential especially in mapping large areas and monitoring temporal changes relating to N release.
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