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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
41

Rudens–žiemos laikotarpio meteorologinių sąlygų įtaka skirtingu laiku sėtų žieminių rapsų derliaus formavimosi ypatumams / The influence of meteorological conditions of autumn-winter period on yield formation of winter oilseed rape sown at different time

Balinskienė, Sigita 13 June 2012 (has links)
Baigiamajame darbe pateikiami lauko eksperimento, vykdyto Aleksandro Stulginskio universiteto bandymų stotyje 2010–2011 m., duomenys. Dirvožemis karbonatingas sekliai glėjiškas išplautžemis (Calc(ar)i-Epihypogleyic Luvisol). Tyrimo tikslas – įvertinti sėjos laiko įtaką linijinių ir hibridinių žieminių rapsų derliaus formavimuisi skirtingos trukmės šiltėjančiu rudens – žiemos periodu. Sėjos laikas ir veislė turėjo esminės įtakos žieminių rapsų pasėlių tankumui rudenį. Rugpjūčio 20 d., rugsėjo 5 ir 10 d. sėtų skirtingų veislių žieminių rapsų pasėlių tankumas skyrėsi esmingai – tankesni buvo linijinės veislės rapsų pasėliai. Žieminių rapsų sudygimui įtakos turėjo meteorologinės sąlygos dygimo metu, ypač – kritulių kiekis ir intensyvumas. Sėjos laikas turėjo esminės įtakos rapsų biometriniams rodikliams rudenį prieš žiemojimą. Veislės esminė įtaka nustatyta tik lapų skaičiui pasėjus žieminius rapsus rugpjūčio mėnesį. Pasibaigus atsinaujinusiai vegetacijai rudens–žiemos laikotarpiu, sėjos laiko įtaka rapsų biometriniams rodikliams išliko esminė. Didesnę antžeminės dalies masę, lapų skaičių bei šaknų masę užaugino ‘Kronos’ veislės žieminiai rapsai. Atsinaujinus vegetacijai pavasarį, sėjos laikas turėjo esminės įtakos antžeminės dalies masei bei šaknų masei, tuo tarpu lapų skaičiui esminės įtakos nebuvo. ‘Kronos’ veislės žieminiai rapsai suformavo esmingai didesnę šaknų masę, juos sėjant rugpjūčio 10 d. Trumpas pasiruošimo žiemojimui laikotarpis, nepalankios meteorologinės sąlygos... [toliau žr. visą tekstą] / Data of the field experiment completed on the experiment station at Aleksandras Stulginskis University in the period 2010 – 2011 are analysed in the thesis. Soil of the experiment field - (Calc(ar)i-Epihypogleyic Luvisol). Aim of the research – to estimate the effect of the linear and hybrid winter rape yield formation during the warming autumn – winter period. Sowing time and variety had significant effect on winter rape crop thickness in autumn. Thickness of the crop of the considered winter rape varieties sown August 20, September 5 and 10 differed, considerably. Thicker crop was recorded for the linear rape variety. Meteorological conditions especially precipitation amount and intensity were found to have significant effect on winter rape germination. Sowing time contributed significantly to the biometric rape indices before wintering. The obtained data revealed the effect of variety on the number of winter rape leaves sown in August. The effect of the sowing time after the end of renewed vegetation in autumn-winter period was found to be significant. ‘Kronos’ variety winter rape produced higher above-ground mass, leaves number and root mass. The sowing time was found to have a significant effect not only on the above-ground mass but also on root mass. ‘Kronos’ variety winter rape sown August 10 were recorded to produce considerably higher root mass. Due to unfavourable meteorological conditions at the end of winter the rape sown August 10 and 20 over-wintered. Sowing... [to full text]
42

Biologinių preparatų įtaka žieminių rapsų vystymuisi / Influence of biological preparations on winter rape

Liakaitė, Lina 13 June 2012 (has links)
Magistrantūros studijų baigiamojo darbo tyrimų tikslas buvo įvertinti skirtingų biologinių preparatų, kaip dirvos aktyvatorių, naudojamų rudenį ant priešsėlio (žieminių kviečių) ražienų, bei pavasarį, rapsams esant butonizacijos tarpsnyje, poveikį žieminių rapsų vystymuisi bei derliaus formavimuisi. Lauko eksperimentas buvo atliktas 2010–2011 m. ASU Bandymų stotyje. Dirvožemis IDg8-k (LVg-p-w-cc) – karbonatingas sekliai glėjiškas išplautžemis (Calc(ar)i-Epihypogleyic Luvisols). Darbo objektas – Žieminis rapsas (Brassica napus ssp. oleifera), linijinė veislė ‘Sunday’. Darbo metodai: Žieminių rapsų biometriniai matavimai, sėklų derlingumas bei derliaus struktūros elementai nustatyti tiesioginio matavimo, skaičiavimo ar svėrimo būdu pagal priimtas lauko eksperimento vykdymo metodikas. Tyrimų duomenys statistiškai įvertinti vieno veiksnio arba dviejų veiksnių kiekybinių požymių dispersinės analizės metodais, taikant kompiuterinę programą ANOVA (Tarakanovas, Raudonius, 2003). Darbo rezultatai. Esmingai didžiausias žieminių rapsų šaknies kaklelio skersmuo (13 mm) prieš augalų žiemojimą nustatytas variante, kur ant žieminių kviečių ražienų buvo išpurkštas biologinių preparatų Azofit (1,0 l ha-1) ir Amalgerol (3,0 l ha-1) derinys. Šiame variante peržiemojo 9,73 % daugiau augalų nei kontroliniame. Esmingai didžiausias žieminių rapsų sėklų derlingumas (3,25 t ha-1) gautas variante, kuriame Azofit (1,0 l ha-1) ir Amalgerol (3,0 l ha-1) derinys išpurkštas rudenį ir pavasarį, tai 1,5 t... [toliau žr. visą tekstą] / The main objective of Master thesis research was to evaluate various biological agents, as soil activators, which are used in the fall on the preceding crop (winter wheat) stubble and in spring on rape at bud formation stage, and the impact that these biological agents do to winter rapeseed crop development and formation. Field experiment was conducted in 2010–2011 at ASU Experimental Station. The soil type – Calc(ar)i-Epihypogleyic Luvisols (LVg-p-w-cc). The object – winter rape (Brassica napus ssp. Oleifera) linear sort 'Sunday'. Working methods: biometric measurements of winter rape, seed yield and yield structure elements were determined while using direct measurements, calculations or weighing according field experimental techniques. Research data have been statistically evaluated with a single factor or two factor analysis of variance of quantitative methods of evidence, using a computer program ANOVA (Tarakanovas, Raudonius, 2003). Research results. The biggest winter rape root collar diameter (13 mm) before winter was found in variant, where the winter wheat stubble was sprayed with the combination of biological preparations Azofit (1.0 l ha-1) and Amalgerol (3.0 l ha-1). In this variant 9.73% more plants survived winter than in control field. The biggest winter rapeseed yield (3.25 t ha-1) was obtained in the variant where a combination of Azofit (1.0 l ha-1) and Amalgerol (3.0 l ha-1) was sprayed in the autumn and spring, it was 1.5 t ha -1 higher than in the... [to full text]
43

Genetic variation and inheritance of seed fibre content in winter oilseed rape (Brassica napus L.)

Suprianto, Edy 22 May 2014 (has links)
No description available.
44

Význam přírodě blízkých biotopů pro poskytování ekosystémových služeb střevlíky (Carabidae) na poli řepky ozimé / Importance of natural biotopes for the utilization of ecosystem services by ground beetles (Carabidae) in a winter rape field

KDOLSKÝ, Tomáš January 2014 (has links)
This diploma thesis deals with the importance of semi-natural biotopes for the carabid beetles (Coleoptera: Carabidae) and benefits of these beetles for the production of the oilseed rape. Evaluation was done by measuring the diversity of communities of carabid beetles by pitfall trapping followed by the evaluation of total abundance, Shannon´s diversity index and the Shannon´s evenness index in the field oilseed rape and in the adjacent semi-natural biotopes. Diversity was measured at two locations (location A, B). Monitored biotopes of the location A were the meadow, the field, the unmanaged field boundary and the forest. At the site B, monitored biotopes were the meadow and the field. Carabid beetles were captured in one-week intervals continuously from May to September 2013. In total 3076 individuals represented by 78 species were captured. The most numerous species in samples were Poecilus cupreus, Pterostichus melanarius, Poecilus versicolor, Pseudoophonus rufipes and Loricera pilicornis, which formed together 72 % of the total numbers. The monitored biotopes of location A did not differ significantly in total abundance (p = 0.13) nor in the Shannon´s eveness (p = 0.43). They differed by the diversity index (p = 0.03), but this accounted for difference between the field boundary and the forest biotopes (p = 0.04). No difference in the three measured parameters were found by the comparison the field sites and next semi-natural sites at locality A (i.e. meadow A/field A1, forest/field A2), nor by comparing the biotopes field and meadow in both the localities (A, B) in one model (p < 0.05). The results suggest the importance of the immigration of carabid from the semi-natural biotopes into the field, which supports the field populations of carabids and the ecosystem service of biological control provided by them.
45

Studium vlivu stresových faktorů na fotosyntézu, vodivost průduchů a transpiraci brukve řepky olejky (Brassica napus L. var. napus) / Investigation of the impact of stress factors on photosynthesis and transpiration of rape (/Brassica napus /L. var./napus/)

BICANOVÁ, Laura January 2016 (has links)
The thesis deals with the influence of cold plasma treatment of seeds such as stress factor to the photosynthesis rate, transpiration and stomatal conductance of brassica oilseed rape (Brassica napus L. var. napus). The theoretical part is focused on the cold plasma, its application and effects on plant physiology, photosynthetic process and description of examined oilseed rape crops. The literature review is followed by the experiment which studies the influence of cold plasma on the physiological processes of plants. The seeds of oilseed rape have been treated with cold plasma in various intervals and cultivated plants were subjected to measuring device Licor Li 6400 XT. The results show that cold plasma treatment of brassica oilseed rape influences the physiological processes depending on the length of exposure and the plant age.
46

Recherche de nouveaux leviers pour cribler la résistance du colza (Brassica napus) au méligèthe (Brassicogethes aeneus) : de la métabolomique au champ / Finding new targets to screen oilseed rape (Brassica napus) resistance to pollen beetle (Brassicogethe aeneus) : from metabolomics to the field

Seimandi Corda, Gaëtan 27 April 2018 (has links)
Les insectes phytophages causent des dommages importants aux cultures. Ces insectes sont principalement contrôlés par l’utilisation d’insecticides mais les effets néfastes des composés utilisés sur la santé humaine et l’environnement ainsi que l’apparition de populations résistantes à ces composés imposent de trouver des stratégies de lutte alternatives. Sélectionner des plantes pour leur résistance aux insectes pourrait être une solution intéressante. Un frein majeur au développement de cette stratégie est le fait qu’un grand nombre de génotypes doit être criblé pour identifier des sources de résistance et que le phénotypage est souvent complexe et limite les possibilités de criblage à grande échelle. Pour lever ces verrous, il est important de comprendre les mécanismes à l’origine des résistances. Une fois ces mécanismes précisés dans le cadre de l’interaction entre une culture et un ravageur, l’identification de traits clés de cette interaction permet d’envisager l’utilisation de biomarqueurs de la résistance qui peuvent fortement simplifier le phénotypage. Ce type d’approche a été conduit au cours de cette thèse dans le cadre de l’interaction entre le colza (Brassica napus) et l’un de ses principaux ravageurs, le méligèthe (Brassicogethes aeneus). Des travaux antérieurs avaient mis en évidence l’existence de certains composés biochimiques présents dans le périanthe des boutons floraux et corrélés au niveau d’attaque de différents génotypes de colza. Ces résultats avaient été obtenus au laboratoire et il était nécessaire de les confirmer dans des conditions de culture réalistes. Le premier objectif de cette thèse était donc de développer une méthode permettant de cribler au champ différents génotypes de colza pour leur résistance au méligèthe afin de valider ou non le potentiel des composés biochimiques identifiés précédemment comme biomarqueurs mais aussi d’en identifier de nouveaux. Le second objectif de ce travail était de mieux comprendre l’écologie alimentaire du méligèthe afin d’identifier de nouvelles cibles potentielles pour la sélection de plantes résistantes. Nous avons mené plusieurs expérimentations sur le terrain qui nous ont permis de développer une méthode de crible au champ des génotypes de colza pour leur résistance au méligèthe. Cette méthode a mis en évidence l’existence de différences de résistance fortes et robustes entre génotypes parmi une gamme de 19 génotypes testés. Les biomarqueurs potentiels précédemment identifiés n’ont pas été validés au champ mais deux autres composés semblent influencer la résistance au méligèthe et pourraient être utilisés comme futurs biomarqueurs. Ces expériences au champ ont aussi permis de montrer que la biochimie des périanthes était très dépendante des conditions environnementales, ce qui pourra compliquer le travail de sélection. Par ailleurs, des expériences de développement réalisées en conditions contrôlées ont montré que le méligèthe utilisait le nectar présent dans les fleurs de colza mais que celui-ci ne semblait pas affecter son développement. Le pollen semble, jouer un rôle important sur son développement mais les larves parviennent à se développer sans son apport. Les expériences sur le comportement alimentaire du méligèthe adulte ont montré que cet insecte avait un patron d’attaque spécifique sur les inflorescences de colza en s’alimentant avant tout sur les boutons de petite taille (donc moins riches en pollen par rapport aux gros). Il semble que la disponibilité mais surtout l’accessibilité du pollen médiée par le périanthe joue un rôle essentiel dans le comportement de cet insecte. Ce travail a permis de mieux comprendre le comportement alimentaire du méligèthe et d’identifier des traits importants pour son développement. Ce travail montre que des résistances modérées existent au sein du colza et qu’elles pourraient être utilisées pour la sélection variétale. Il pointe aussi les limites des approches basées sur des biomarqueurs biochimiques. / Herbivorous insects cause important yield losses to crops. These insects are mainly managed through insecticides but negative effects of used compounds on the human health and the environment as well as the development of resistant pest populations impose finding alternative strategies to manage them. Breeding plants for enhanced resistance to insects is an attractive strategy. This kind of strategy was already implemented to manage insects but examples of its utilisation remain rare. The main limitation of this strategy is that a large number of genotypes needs to be screened through generally complex phenotyping methods to identify resistances. To circumvent these issues, an approach based on the understanding of plant defence mechanisms and the utilisation of biochemical biomarkers linked to resistance could be interesting. During this PhD, this kind of approach was developed on the oilseed rape (Brassica napus) and one of its main pests, the pollen beetle (Brassicogethes aeneus). Previous studies identified chemical compounds present in the perianth of flower buds and correlated to oilseed rape resistance to pollen beetle. However these studies were carried out in the laboratory and need to be validated in field conditions. Moreover, information on pollen beetle feeding ecology are still lacking while they could help identifying new targets for breeding. The first objective of this PhD is to develop a method allowing to screen resistance to the pollen beetle in the field. This method will allow to confirm the potential biomarkers previously identified and to look for additional biomarkers. The second objective of the present work was to better understand key steps in the interaction between the pest and its host plant to identify potential new target traits for resistance. For this purpose, the importance of food sources present in flowers such as pollen and nectar on pollen beetle development and the factors impacting the feeding pattern of adults on the inflorescence were investigated. We conducted field experiments in two different sites and for two consecutive years and propose a method allowing to screen oilseed rape resistance to pollen beetle in the field. Using this method, we were able to identify genotypes with moderate levels of resistance among a set of 19 genotypes. Previously identified biochemical biomarkers were not correlated with plant resistance in the field but new markers were identified (i.e. quinic acid and arginine). Our field experiments also showed that plant composition is highly variable according to the environment and this variability could affect usefulness of these markers during plant breeding programs. Experiments under controlled conditions also showed that pollen beetle used nectar for feeding but that it did not seem to affect its development. Pollen, on the other hand, seemed to have a more important impact but was not indispensable to pollen beetle development. The study of the pollen beetle feeding behaviour showed that this insect has a surprising feeding pattern on oilseed rape inflorescences and that small buds are more used for feeding than large buds that contain more pollen. It seems that accessibility and to a lesser extend availability of feeding resource explain this pattern and that the perianth has a major role on this preference. These experiments allowed to better understand the pollen beetle feeding ecology and to identify plant traits important for its development. Our work showed that moderate levels of resistance are present in oilseed rape and could be used in breeding programs. Limitations of approaches based on biochemical biomarkers are discussed.
47

Effectiveness of resistance against Leptosphaeria species (phoma stem canker) in oilseed rape

Mitrousia, Georgia January 2016 (has links)
To improve understanding of the effectiveness of host resistance against Leptosphaeria spp., three aspects of effectiveness of resistance were investigated. With focus on the major Rlm-mediated resistance against L. maculans, changes in effectiveness of Rlm7-mediated resistance to prevent initiation of disease epidemics at the leaf spot stage were investigated in winter oilseed rape field experiments at five sites in the UK over the period with the cropping seasons 2009/2010 - 2013/2014. L. maculans isolates virulent against Rlm7 were identified in the UK. This may be associated with observed changes in lesion phenotypes on the Rlm7 cultivars in field conditions. However, despite increased severity of phoma leaf spotting on Rlm7 cultivars, there was no associated increase in phoma stem canker severity at the end of the cropping seasons. The effectiveness of winter oilseed rape cultivars for control of phoma stem canker (caused by L. maculans or L. biglobosa) was affected by the coexistence of the two Leptosphaeria species in oilseed rape crops. Weather conditions influenced ascospore release of both species and favoured L. biglobosa ascospore release in 2011, resulting in subsequent increased L. biglobosa phoma leaf spotting and stem canker severity. However, coexistence of Leptosphaeria spp. on oilseed rape crops was affected by the cultivar resistance against L. maculans. CE experiments showed that there were interactions between the two Leptosphaeria spp. in planta. Their coexistence on B. napus was influenced by the different host responses that they trigger during host colonisation. Effects of increased temperature on effectiveness of resistance against L. maculans and on severity of symptoms by Leptosphaeria spp. on B. napus were investigated. Increased temperature affected both Rlm4- and Rlm7-mediated resistance, when assessed by phenotypic and molecular techniques. Increased temperature was associated with increased symptom severity, for both L. maculans and L. biglobosa lesions on plants. Cultivar quantitative resistance background increased effectiveness of resistance against phoma stem canker pathogens at increased temperature and should be deployed in in strategies for adaptation to climate change to avoid increased phoma stem canker epidemics in the future.
48

Verticillium longisporum on oilseed rape (Brassica napus L.) / Differential roles of salicylic acid, seed transmission and plant colonization in greenhouse and field conditions

Zheng, Xiaorong 05 February 2018 (has links)
No description available.
49

Critical Factors of Post-Harvest Nitrous Oxide Emissions from Oilseed Rape – Cereal Rotations / Evaluations Based on Field Studies and Stable Isotope Labeling

Köbke, Sarah 17 May 2017 (has links)
No description available.
50

Hodnocení zátěže životního prostředí v ČR pomocí indikátoru Vodní stopa / Environmental assessment of the Czech Republic based on Water Footprint

Žlábková, Jana January 2013 (has links)
This dissertation sets its goal in application of the water footprint indicator, which is a practical and multi-layered indicator of water sources consumption. Of human activities, agriculture presents the most significant demands on water sources consumption. Therefore I have turned my focus to the widely-discussed issue of biofuels production, because the input materials for production of this kind of energy are agricultural crops (in the Czech republic those are: oilseed rape, sugar beet, Indian corn and winter wheat). The calculated results of water footprints of the selected industrial crops (m3 /t) and of water footprints of the heating value units of that crops (m3 /GJ) offer us a concrete notion of energy requirements of water of that chosen industrial crops in the conditions of the Czech republic. Keywords: water footprint indicator, biofuels, oilseed rape, water consumption, biodiesel, bioethanol, evapotranspiration.

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