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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.
51

Avaliação da qualidade de forragem hidropônica de centeio, cevada e ervilhaca / Evaluation of the quality of hydroponics forage Hordeum vulgare L. ,Secale cereale L. and Vicia sativa L.

Zorzan, Marise Helena Saldanha 10 February 2006 (has links)
It was carried an experiment, in the Fitotecnia Department of the Federal University of Santa Maria (UFSM) - RS, with objective to evaluate the nutritional quality of two species of grassy (Hordeum vulgare L. and Secale cereale L.), cultivated in hydroponic, during of autumn and winter and to evaluate the nutritional quality of two species of grassy (Hordeum vulgare L. and Secale cereale L) joined to a legume (Vicia sativa L.), cultivated in hydroponic, during autumn and winter. It was adopted the experimental delineation entirely casuistic with four repetitions. The data had been submitted to the variance analysis. The averages of the qualitative variables had been compared among themselves for Tukey test with 5% of error probability. The hydroponic Secale cereale L forage showed bigger dry mass and mineral substance in autumn and winter, surpassing the Hordeum vulgare L forage, Hordeum vulgare L.: intercropping+Vicia sativa L and Secale cereale L+Vicia sativa L. Hydroponic Secale cereale L forage intercropping+Vicia sativa L 150 presented bigger dry mass than the others treatments, however, the mineral substance resulted in minors values, what negatively differentiated in relation the Secale cereale L forage. The biggest fiber value in neutral detergent found, was in the hydroponic Hordeum vulgare L. forage, although it did not show significant difference in relation to the others treatments. The hydroponic Secale cereale L forage presented a bigger rude protein value in relation to the others treatments. The hydroponic forages it did not show significant difference in relation to energetic value and value of phosphorus. The biggest value of calcium and magnesium had been found in the hydroponic Secale cereale L. forage. The Hordeum vulgare L. produced in the 2002 winter, presented minors potassium value, differing significantly from the Hordeum vulgare L intercropping + Vicia sativa L 300 and Secale cereale L + Vicia sativa L 150. / Foi realizado um experimento, no Departamento de Fitotecnia da Universidade Federal de Santa Maria (UFSM) RS, com objetivo de avaliar a qualidade nutricional de duas espécies de gramíneas (cevada e centeio), cultivadas em hidroponia, no período de outono e inverno e avaliar a qualidade nutricional de duas espécies de gramíneas (cevada e centeio) consorciadas a uma leguminosa (ervilhaca), cultivadas em hidroponia, no período de outono e inverno. Adotou-se o delineamento experimental inteiramente casualizado com quatro repetições. Os dados obtidos foram submetidos à análise de variância. As médias das variáveis qualitativas foram comparadas entre si pelo teste de Tukey a 5% de probabilidade de erro.A forragem hidropônica de centeio apresentou maior massa seca e matéria mineral no outono e inverno, superando a forragem de cevada, consórcio de cevada + ervilhaca e centeio + ervilhaca. O consórcio de forragem hidropônica de centeio + ervilhaca 150 apresentou maior massa seca que os demais tratamentos consorciados, entretanto, a matéria mineral resultou em menores valores, o que diferenciou negativamente em relação à forragem de centeio. O maior teor de fibra em detergente neutro (FDN) encontrado, foi na forragem hidropônica de cevada, apesar de não ter apresentado diferença significativa em relação aos demais tratamentos. A forragem hidropônica de centeio apresentou um maior teor de proteína bruta em relação aos demais tratamentos. As forragens hidropônicas não apresentaram diferença significativa para o valor energético e o teor de fósforo. Os maiores teores de cálcio e magnésio foram encontrados na forragem hidropônica de centeio. A cevada produzida no inverno de 2002 apresentou menores teores de potássio, diferindo significativamente do consórcio de cevada + ervilhaca 300 e centeio + ervilhaca 150.
52

Avaliação da qualidade de forragem hidropônica de centeio, cevada e ervilhaca / Evaluation of the quality of hydroponics forage hordeum vulgare l. ,secale cereale l. and vicia sativa l.

Zorzan, Marise Helena Saldanha 10 February 2006 (has links)
It was carried an experiment, in the Fitotecnia Department of the Federal University of Santa Maria (UFSM) - RS, with objective to evaluate the nutritional quality of two species of grassy (Hordeum vulgare L. and Secale cereale L.), cultivated in hydroponic, during of autumn and winter and to evaluate the nutritional quality of two species of grassy (Hordeum vulgare L. and Secale cereale L) joined to a legume (Vicia sativa L.), cultivated in hydroponic, during autumn and winter. It was adopted the experimental delineation entirely casuistic with four repetitions. The data had been submitted to the variance analysis. The averages of the qualitative variables had been compared among themselves for Tukey test with 5% of error probability. The hydroponic Secale cereale L forage showed bigger dry mass and mineral substance in autumn and winter, surpassing the Hordeum vulgare L forage, Hordeum vulgare L.: intercropping+Vicia sativa L and Secale cereale L+Vicia sativa L. Hydroponic Secale cereale L forage intercropping+Vicia sativa L 150 presented bigger dry mass than the others treatments, however, the mineral substance resulted in minors values, what negatively differentiated in relation the Secale cereale L forage. The biggest fiber value in neutral detergent found, was in the hydroponic Hordeum vulgare L. forage, although it did not show significant difference in relation to the others treatments. The hydroponic Secale cereale L forage presented a bigger rude protein value in relation to the others treatments. The hydroponic forages it did not show significant difference in relation to energetic value and value of phosphorus. The biggest value of calcium and magnesium had been found in the hydroponic Secale cereale L. forage. The Hordeum vulgare L. produced in the 2002 winter, presented minors potassium value, differing significantly from the Hordeum vulgare L intercropping + Vicia sativa L 300 and Secale cereale L + Vicia sativa L 150. / Foi realizado um experimento, no Departamento de Fitotecnia da Universidade Federal de Santa Maria (UFSM) RS, com objetivo de avaliar a qualidade nutricional de duas espécies de gramíneas (cevada e centeio), cultivadas em hidroponia, no período de outono e inverno e avaliar a qualidade nutricional de duas espécies de gramíneas (cevada e centeio) consorciadas a uma leguminosa (ervilhaca), cultivadas em hidroponia, no período de outono e inverno. Adotou-se o delineamento experimental inteiramente casualizado com quatro repetições. Os dados obtidos foram submetidos à análise de variância. As médias das variáveis qualitativas foram comparadas entre si pelo teste de Tukey a 5% de probabilidade de erro.A forragem hidropônica de centeio apresentou maior massa seca e matéria mineral no outono e inverno, superando a forragem de cevada, consórcio de cevada + ervilhaca e centeio + ervilhaca. O consórcio de forragem hidropônica de centeio + ervilhaca 150 apresentou maior massa seca que os demais tratamentos consorciados, entretanto, a matéria mineral resultou em menores valores, o que diferenciou negativamente em relação à forragem de centeio. O maior teor de fibra em detergente neutro (FDN) encontrado, foi na forragem hidropônica de cevada, apesar de não ter apresentado diferença significativa em relação aos demais tratamentos. A forragem hidropônica de centeio apresentou um maior teor de proteína bruta em relação aos demais tratamentos. As forragens hidropônicas não apresentaram diferença significativa para o valor energético e o teor de fósforo. Os maiores teores de cálcio e magnésio foram encontrados na forragem hidropônica de centeio. A cevada produzida no inverno de 2002 apresentou menores teores de potássio, diferindo significativamente do consórcio de cevada + ervilhaca 300 e centeio + ervilhaca 150.
53

Reprodukční izolace diploidů a tetraploidů druhu Vicia cracca a možnosti evoluce tohoto agregátu / Reproductive isolation between diploid and tetraploid cytotype of Vicia cracca and possibilities of evolution of this aggregate

Vlčková, Zuzana January 2015 (has links)
Master thesis investigates reproductive barriers in diploid-polyploid complex of Vicia cracca. Complex with basic chromosome number x=7 consists of diploid (2x=14), tetraploid (4x=28) and rare triploid (3x=21) cytotype. I studied prereproductive barriers between diploid and tetraploid cytotype: phenology of flowering, pollinators' behavior (preference of spieces of pollinators to cytotypes, sequence of visited cytotypes), variables, that could explain pollinators' behavior (amount of nectar as the main reward, size and amount of pollen grains as a potentional reward). To find out how strong the triploid block is I analyzed ploidy of seeds and seedlings from mixed-ploidy population. The habitat isolation showed up to be the strongest reproductive barrier. Pollinator's behavior meaningfully contributes to isolation, phenology of flowering contributes only minimally. Index expressing rate of prereproductive barriers is 0,956. Pollinator Bombus pascuorum visited on one locality preferably tetraploid plants and Andrena sp. preferred diploid plants. Even though tetraploid plants produce more nectar, no other analysis showed pollinators' preference to tetraploid plants. I prepared one squash of diploid V. cracca using method of in situ hybridization. This method needs to be optimilized for the studied taxon.
54

Biomass, root distribution and overyielding potential of faba bean/wheat and white clover/ryegrass mixtures

Streit, Juliane 06 November 2018 (has links)
No description available.
55

Vliv popínavých leguminóz na výskyt hodnotných a plevelných druhů v trvalých travních porostech. / The influence of climbing legumes on presence of valuable and weedy species in permanent grasslands

HRAŠE, David January 2018 (has links)
Permanent grassland is a complex of legumes, herbs, and grasses. They are an important plant component of the biosphere. They provide wide range of productive and non-productive functions. Climbing legumes are valuable species in grasslands. They are involved in higher quality of fresh matter and hay. The aim of this diploma thesis is to assess the influence of climbing legumes on the presence and coverage of other higher plant species in grassland, the height and productivity of vegetation in selected localities in the Prachatice district in 2017. The occurrence of legumes (climbing and non-climbing) has a significant impact on other species in the grassland community. The reason is the ability to fix aerial nitrogen and support grass species that require a good nitrogen supply. The obtained data were statistically processed.
56

Inter- a intraspecifická variabilita v odezvě Vicia faba L. a Zea mays L. na nedostatek vody / Inter- and intraspecific variability in Vicia faba L. and Zea mays L. response to water deficit

Fridrichová, Lenka January 2010 (has links)
This work monitors the response of plants to water deficit and subsequent restoration of water availability with the aim to expand our knowledge about plant behaviour during and after drought stress from the perspective of two plant species with a different type of photosynthesis. A particular attention was paid to the intraspecific differences and their possible changes during stress and post-stress periods. The plant response was monitored as the changes of selected photosynthetic, morphological and developmental characteristics caused by the cessation of watering for six days followed by a six-day period of renewed optimal water supply. The experiments were carried out on plants with different types of photosynthesis - C3 plant Vicia faba L and C4 plant Zea mays L.; for both plant species, three varieties / genotypes were monitored. The response of both plant species to insufficient water supply differed by the extent of changes in relative water content (RWC), chlorophyll fluorescence parameters, the dry mass of individual leaves (developed during the stress period), the ratio between the aboveground dry mass and dry mass of roots. In drought-stressed plants, downward trend in RWC was observed, as well as the increase of the minimum yield of chlorophyll fluorescence in dark-adapted leaves (F ),...
57

Reakce různých genotypů Zea mays L. a Vicia faba L. ošetřených brassinosteroidy na působení vodního deficitu / Response of different genotypes of Zea mays L. and Vicia faba L. treated with brassinosteroids to water deficit

Kuklíková, Radka January 2011 (has links)
This work monitors the response of plants to the application of a solution of synthetic brassinosteroid (5-fluor-3α,17β-dihydroxy-5α-pregnan-6-on) under drought stress conditions and subsequent restoration of water availability. The response of two plant species was monitored under six-day period of cessation of watering and under six-day period of renewed optimal water supply. The experiments were carried out on plants with different type of photosynthesis - C3 plant Vicia faba L. and C4 plant Zea mays L.. For both plant species, three varieties/genotypes were used. Photosynthetic, morphological and developmental characteristics were monitored. The brassinosteroid treatment influenced more the morphological than the photosynthetic characteristics. The content of photosynthetic pigments was influenced more than the chlorophyll fluorescence parameters. The differences in morphological characteristics between individual varieties/genotypes were observed. The response to the application of brassinosteroid was observed especially for drought-sensitive variety/genotype. Application of brassinosteroid caused increase of the dry mass of leaves and roots, the height to leaf , the height of the whole plant and its increment under stress and post-stress periods in both plant species. The content of...
58

Understorey management for the enhancement of populations of a leafroller (Lepidoptera: Tortricidae) parasitoid (Dolichogenidea tasmanica (Cameron)) in Canterbury, New Zealand apple orchards

Irvin, N. A. January 1999 (has links)
This study investigated understorey management in Canterbury, New Zealand, apple orchards for the enhancement of populations of Dolichogenidea tasmanica (Cameron) (Braconidae) for leafroller (Lepidoptera: Tortricidae) biological control. The first objective was to determine the influence of understorey plants on the abundance of D. tasmanica and leafroller parasitism, and to investigate the mechanisms behind this influence. The second was to determine the most suitable understorey plants in terms of their ability to enhance parasitoid abundance, leafroller parasitism, parasitoid longevity, parasitoid fecundity and its ability to not benefit leafroller. Results from three consecutive field trials showed that buckwheat (Fagopyrum esculentum Moench), coriander (Coriandrum sativum L.), alyssum (Lobularia maritima (L.) Desv), and, to a lesser extent, broad bean (Vicia faba L.), enhanced parasitoid abundance and leafroller parasitism. The mechanisms behind the effects of understorey plants had previously been unexplored. However, results here showed that it was the flowers or the buckwheat that 'attracted' the parasitoid to the plant and not the shelter, aphids or microclimate that the plant may also provide. Providing flowering plants in the orchard understorey also increased immigration of parasitoids and enhanced parasitoids and enhanced parasitoid longevity and fecundity in the laboratory. In contrast, the understorey plants had no influence on the female:male ratio of D. tasmanica. Although coriander enhanced leafroller parasitism three-fold in field experiments compared with controls, it failed to enhance the longevity of both sexes of D. tasmanica in the laboratory compared with water-only. Broad bean significantly enhanced parasitoid abundance three-fold and significantly increased parasitism from 0% to 75% compared with the controls on one leafroller release date. However, laboratory trials showed that of male D. tasmancia but it did not enhance female longevity. Also, female D. tasmanica foraging on broad bean produced a total of only three parasitoid cocoons, but this result was based on an overall 6.5% survival of larvae to pupae or to parasitoid cocoon. Furthermore, results suggested that extrafloral nectar secretion decreased as the plants matured. Phacelia (Phacelia tanacetifolia Benth.) did not significantly enhance parasitism rate in the field compared with controls, and numbers of D. tasmanica captured by suction sampling were significantly lower in phacelia treatments compared with alyssum, buckwheat and control plots. Also, laboratory experiments showed that survival of D. tasmanica on phacelia flowers was equivalent to that on water-only and significantly lower than on buckwheat. These results suggest that phacelia does not provide nectar to D. tasmanica, only pollen, and therefore is not a suitable understorey plant for D. tasmanica enhancement in orchards. Buckwheat and alyssum showed the most potential as understorey plants for the enhancement of natural enemies. Buckwheat not only increased numbers of D. tasmanica seven-fold, but also increased numbers of beneficial lacewings (Micromus tasmaniae (Walker)) and hover flies (Syrphidae) captured on yellow sticky traps compared with the controls. It significantly increased leafroller parasitism by D. tasmanica from 0% to 86% compared with the controls (on one date only), and in the laboratory enhanced D. tasmanica longevity and increased fecundity compared with water-only. Similarly, alyssum significantly increased parasitism rate compared with controls, and two-fold more D. tasmanica were suction sampled in these plots compared with controls. It also enhanced longevity of both sexes of D. tasmanica compared with water, and showed the most favourable characteristics in terms of being of no benefit to leafrollers. This is because it was not preferred over apple by leafroller larvae and when they were forced to feed on it, it caused high mortality (94.3%) and low pupal weight (15 mg). Furthermore, alyssum did not enhance the number of fertile eggs produced by adult leafrollers compared with water only. However, further research is required to address the overall effect of buckwheat and alyssum on crop production and orchard management, including effects on fruit yield and quality, frost risk, disease incidence, soil quality, weeds and other pests. Also, research into the ability of these plants to survive in the orchard with little maintenance, and into the optimal sowing rates, would be useful. Sampling natural populations of leafroller within each treatment showed that damage from leafrollers and the number of leafroller larvae were respectively 20.3% and 29.3% lower in the flowering treatments compared with the controls. Furthermore, field trials showed up to a six-fold increase in leafroller pupae in controls compared with buckwheat and alyssum. This suggests that increasing leafroller parasitism rate from understorey management in orchards will translate into lower pest populations, although neither larval numbers/damage nor pupal numbers differed significantly between treatments. Trapping D. tasmanica at a gradient of distances showed that this parasitoid travels into rows adjacent to buckwheat plots, indicating that growers may be able to sow flowering plants in every second or third row of the orchard, and still enhance leafroller biocontrol while minimising the adverse effects of a cover crop. Sowing buckwheat and alyssum in orchard understoreys may enhance biological control of apple pests in organic apple production and reduce the number of insect growth regulators applied in IFP programmes. However, the challenge still remains to investigate whether conservation biological control can reduce leafroller populations below economic thresholds.
59

Understorey management for the enhancement of populations of a leafroller (Lepidoptera: Tortricidae) parasitoid (Dolichogenidea tasmanica (Cameron)) in Canterbury, New Zealand apple orchards

Irvin, N. A. January 1999 (has links)
This study investigated understorey management in Canterbury, New Zealand, apple orchards for the enhancement of populations of Dolichogenidea tasmanica (Cameron) (Braconidae) for leafroller (Lepidoptera: Tortricidae) biological control. The first objective was to determine the influence of understorey plants on the abundance of D. tasmanica and leafroller parasitism, and to investigate the mechanisms behind this influence. The second was to determine the most suitable understorey plants in terms of their ability to enhance parasitoid abundance, leafroller parasitism, parasitoid longevity, parasitoid fecundity and its ability to not benefit leafroller. Results from three consecutive field trials showed that buckwheat (Fagopyrum esculentum Moench), coriander (Coriandrum sativum L.), alyssum (Lobularia maritima (L.) Desv), and, to a lesser extent, broad bean (Vicia faba L.), enhanced parasitoid abundance and leafroller parasitism. The mechanisms behind the effects of understorey plants had previously been unexplored. However, results here showed that it was the flowers or the buckwheat that 'attracted' the parasitoid to the plant and not the shelter, aphids or microclimate that the plant may also provide. Providing flowering plants in the orchard understorey also increased immigration of parasitoids and enhanced parasitoids and enhanced parasitoid longevity and fecundity in the laboratory. In contrast, the understorey plants had no influence on the female:male ratio of D. tasmanica. Although coriander enhanced leafroller parasitism three-fold in field experiments compared with controls, it failed to enhance the longevity of both sexes of D. tasmanica in the laboratory compared with water-only. Broad bean significantly enhanced parasitoid abundance three-fold and significantly increased parasitism from 0% to 75% compared with the controls on one leafroller release date. However, laboratory trials showed that of male D. tasmancia but it did not enhance female longevity. Also, female D. tasmanica foraging on broad bean produced a total of only three parasitoid cocoons, but this result was based on an overall 6.5% survival of larvae to pupae or to parasitoid cocoon. Furthermore, results suggested that extrafloral nectar secretion decreased as the plants matured. Phacelia (Phacelia tanacetifolia Benth.) did not significantly enhance parasitism rate in the field compared with controls, and numbers of D. tasmanica captured by suction sampling were significantly lower in phacelia treatments compared with alyssum, buckwheat and control plots. Also, laboratory experiments showed that survival of D. tasmanica on phacelia flowers was equivalent to that on water-only and significantly lower than on buckwheat. These results suggest that phacelia does not provide nectar to D. tasmanica, only pollen, and therefore is not a suitable understorey plant for D. tasmanica enhancement in orchards. Buckwheat and alyssum showed the most potential as understorey plants for the enhancement of natural enemies. Buckwheat not only increased numbers of D. tasmanica seven-fold, but also increased numbers of beneficial lacewings (Micromus tasmaniae (Walker)) and hover flies (Syrphidae) captured on yellow sticky traps compared with the controls. It significantly increased leafroller parasitism by D. tasmanica from 0% to 86% compared with the controls (on one date only), and in the laboratory enhanced D. tasmanica longevity and increased fecundity compared with water-only. Similarly, alyssum significantly increased parasitism rate compared with controls, and two-fold more D. tasmanica were suction sampled in these plots compared with controls. It also enhanced longevity of both sexes of D. tasmanica compared with water, and showed the most favourable characteristics in terms of being of no benefit to leafrollers. This is because it was not preferred over apple by leafroller larvae and when they were forced to feed on it, it caused high mortality (94.3%) and low pupal weight (15 mg). Furthermore, alyssum did not enhance the number of fertile eggs produced by adult leafrollers compared with water only. However, further research is required to address the overall effect of buckwheat and alyssum on crop production and orchard management, including effects on fruit yield and quality, frost risk, disease incidence, soil quality, weeds and other pests. Also, research into the ability of these plants to survive in the orchard with little maintenance, and into the optimal sowing rates, would be useful. Sampling natural populations of leafroller within each treatment showed that damage from leafrollers and the number of leafroller larvae were respectively 20.3% and 29.3% lower in the flowering treatments compared with the controls. Furthermore, field trials showed up to a six-fold increase in leafroller pupae in controls compared with buckwheat and alyssum. This suggests that increasing leafroller parasitism rate from understorey management in orchards will translate into lower pest populations, although neither larval numbers/damage nor pupal numbers differed significantly between treatments. Trapping D. tasmanica at a gradient of distances showed that this parasitoid travels into rows adjacent to buckwheat plots, indicating that growers may be able to sow flowering plants in every second or third row of the orchard, and still enhance leafroller biocontrol while minimising the adverse effects of a cover crop. Sowing buckwheat and alyssum in orchard understoreys may enhance biological control of apple pests in organic apple production and reduce the number of insect growth regulators applied in IFP programmes. However, the challenge still remains to investigate whether conservation biological control can reduce leafroller populations below economic thresholds.

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