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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.
1

Near-natural forests in southern Sweden : silvicultural and palaeoecological aspects on nature-based silviculture /

Björse, Gisela, January 1900 (has links) (PDF)
Diss. (sammanfattning) Alnarp : Sveriges lantbruksuniv. / Härtill 5 uppsatser.
2

Effects of site preparation on soil properties and on growth, damage and nitrogen uptake in planted seedlings /

Nordborg, Fredrik, January 1900 (has links) (PDF)
Diss. (sammanfattning) Alnarp : Sveriges lantbruksuniv., 2001. / Härtill 5 uppsatser.
3

Markberedning med traktorgrävare, prestation och kostnad

Johansson, Bengt January 2012 (has links)
This study investigated the performance and cost of scarification with a tractormounted excavator. Due to variations in terrain conditions the performance variedbetween 0.08 and 0.11 ha/E15h and, with a machine cost of 366 SEK/h, the cost ofscarification varied between 3 330 and 4 750 SEK/ha.
4

Högläggning eller harvning : En jämförande studie av planteringspunkter och markpåverkan vid olika terrängförhållanden. / Mounding or disc trenching? : A comparing study of planting spots and terrain impact in different types of terrain.

Karlsson, Josef January 2016 (has links)
A comparing study of planting spots and terrain impact in different types of terrain.
5

Could Lithospermum officinale be bird dispersed? : A greenhouse experiment

Åberg, Adam January 2015 (has links)
Common gromwell (Lithospermum officinale) acts as a host plant for the monophagous moth Ethmia dodecea  whose larvae are completely dependent on the leaves. As conservation authorities now want to reinstate the regionally extinct moth to Mälardalen, a stable population of its host plant is a requirement. To facilitate the work of strengthening the presence of gromwell a partnership was therefore initiated between Västmanland County Board and Uppsala University. In this cooperation, I performed two studies. In the first one I examined how water and temperature affect plant germination and how nutrient levels affect early growth. In the second study I investigated whether the germination is influenced by chemical treatment (soaking in acid) and mechanical damage (seeds scratched with sandpaper) on the seeds. I worked with the hypothesis that gromwell is grazed by cows and is therefore dispersed and germinates in the spring. This should mean high water levels combined with high temperatures would produce higher germination. For the second study, it means that the germination rate should be higher in the seeds treated with the acid than in the scratched and control treatments. In the first study, so few seeds germinated that I could not draw any conclusions, but germinations appear to go faster in the combination with high nutrients high temperature and frequent watering. In the second study, the seeds scraped with sandpaper had the highest germination rate. This indicates that gromwell may be dispersed by birds, and I propose sandpaper rubbing as a method to easily increase the germination rates of L. officinale in greenhouses in order to reinforce small populations in the field.
6

Armazenamento e tratamentos pré-germinativos em sementes de Punica granatum L. / Storage and pre-germination treatments in Punica granatum L. seeds

Monteiro, Laís Naiara Honorato [UNESP] 12 January 2017 (has links)
Submitted by Laís Naiara Honorato Monteiro null (laismonteiiro@gmail.com) on 2017-02-07T14:21:05Z No. of bitstreams: 1 DISSERTAÇÃO LAÍS_MONTEIRO.pdf: 3540607 bytes, checksum: 1be42b239d144381cc897bf83d7a57b8 (MD5) / Approved for entry into archive by LUIZA DE MENEZES ROMANETTO (luizamenezes@reitoria.unesp.br) on 2017-02-13T15:58:04Z (GMT) No. of bitstreams: 1 monteiro_lnh_me_ilha.pdf: 3540607 bytes, checksum: 1be42b239d144381cc897bf83d7a57b8 (MD5) / Made available in DSpace on 2017-02-13T15:58:04Z (GMT). No. of bitstreams: 1 monteiro_lnh_me_ilha.pdf: 3540607 bytes, checksum: 1be42b239d144381cc897bf83d7a57b8 (MD5) Previous issue date: 2017-01-12 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / A romãzeira (Punica granatum L.), espécie exótica no Brasil, possui grande potencial para exploração comercial por apresentar inúmeras atividades medicinais e nutracêuticas. Porém, sua produção de mudas via sementes não se encontra totalmente elucidada na literatura. Objetivou-se avaliar o efeito do armazenamento e de tratamentos pré-germinativos na emergência e crescimento inicial de plântulas de romãzeira. O experimento foi realizado no Laboratório do Departamento de Fitotecnia, Tecnologia de Alimentos e Sócio-Economia, da UNESP - Câmpus de Ilha Solteira, de agosto a dezembro de 2015. Foram coletados frutos de romã cv. Comum fisiologicamente maduros de pomar comercial localizado no município de Presidente Prudente - SP. Avaliaram-se até estabilização da emergência: início, porcentagem, índice de velocidade e tempo médio de emergência. Aos 50 dias após a semeadura avaliaram-se: número de folhas; diâmetro do caule; comprimento do sistema radicular e da parte aérea e massa de matéria fresca e seca total. Para o experimento de armazenamento (0, 30, 60, 90 e 120 dias em embalagens de sacos de polietileno transparentes, sacos de papel brancos, e frascos de vidro), em um lote das sementes não foi retirado a sarcotesta. Para os experimentos de escarificação e imersão em água (0, 12, 24 e 48 horas) e em GA3 (0, 500, 1000 e 1500 mg L-1), a escarificação em um lote das sementes foi feita com lixa de nº 100. A sarcotesta das sementes de todos experimentos foi retirada utilizando a pressão dessas contra uma peneira com abertura de 2,36 mm em água corrente. Verificou-se que o armazenamento de sementes de romã com sarcotesta é viável em embalagens de polietileno transparentes por até 90 dias, favorecendo variáveis de emergência. Sementes de romã com sarcotesta devem ser semeadas logo após retiradas do fruto para favorecer o crescimento inicial das plântulas. Nos experimentos de escarificação, a associação deste método com imersão em água por 12 horas ou em 500 mg L-1 GA3 reduziu o início e o tempo médio de emergência das sementes de romã. Para emergência e crescimento inicial de plântulas de romã não se faz necessário o uso da escarificação mecânica, da água e do ácido giberélico na imersão das sementes. / The pomegranate (Punica granatum L.), an exotic species in Brazil, has great potential for commercial exploration because it presents innumerable medicinal and nutraceutical activities. However, its production of seedlings via seeds is not fully elucidated in the literature. The objective of this study was to evaluate the effect of storage and pre-germination treatments on emergence and initial growth of pomegranate seedlings. The experiment was conducted in the Plant Science Laboratory of the Department of Plant Science, Food and Socio-Economics of Technology, UNESP – Faculty of Engineering – Ilha Solteira, from August to October 2015. Physiologically mature fruits were collected from adult plants of pomegranate cv. Comum in a commercial orchard located in the Presidente Prudente city. Start, percentage, speed index and emergence mean time were evaluated until emergence stabilization. Fifty days after sowing were evaluated: leaves number; stem diameter, root length, shoot length and total fresh and dry matter. For the storage experiment (0, 30, 60, 90 and 120 days in transparent polyethylene bags, white paper bags, and glass bottles), in lot of seeds the sarcotesta was not sarcotesta. For scarification and water immersion experiments (0, 12, 24 and 48 hours) and in GA3 (0, 500, 1000 and 1500 mg L-1), scarification in a lot of seeds was done with sandpaper nº 100. It was pressed against sieve (2,36 mm aperture) under running water for removal of sarcotesta of all experiments. The storage of pomegranate seeds with sarcotesta is viable in transparent polyethylene packages for up to 90 days, favoring emergency variables. Pomegranate seeds with sarcotesta should be sown after being removed from the fruit to favor the initial growth of the seedlings. In the scarification experiments, the association of this method with immersion in water for 12 hours or in 500 mg L-1 GA3 reduced the start and mean time of emergence pomegranate seeds. For emergence and initial growth of pomegranate seedlings, it is not necessary to use mechanical scarification, water and GA3 in the immersion of seeds.
7

Armazenamento e tratamentos pré-germinativos em sementes de Punica granatum L. /

Monteiro, Laís Naiara Honorato. January 2017 (has links)
Orientador: Aparecida Conceição Boliani / Resumo: A romãzeira (Punica granatum L.), espécie exótica no Brasil, possui grande potencial para exploração comercial por apresentar inúmeras atividades medicinais e nutracêuticas. Porém, sua produção de mudas via sementes não se encontra totalmente elucidada na literatura. Objetivou-se avaliar o efeito do armazenamento e de tratamentos pré-germinativos na emergência e crescimento inicial de plântulas de romãzeira. O experimento foi realizado no Laboratório do Departamento de Fitotecnia, Tecnologia de Alimentos e Sócio-Economia, da UNESP - Câmpus de Ilha Solteira, de agosto a dezembro de 2015. Foram coletados frutos de romã cv. Comum fisiologicamente maduros de pomar comercial localizado no município de Presidente Prudente - SP. Avaliaram-se até estabilização da emergência: início, porcentagem, índice de velocidade e tempo médio de emergência. Aos 50 dias após a semeadura avaliaram-se: número de folhas; diâmetro do caule; comprimento do sistema radicular e da parte aérea e massa de matéria fresca e seca total. Para o experimento de armazenamento (0, 30, 60, 90 e 120 dias em embalagens de sacos de polietileno transparentes, sacos de papel brancos, e frascos de vidro), em um lote das sementes não foi retirado a sarcotesta. Para os experimentos de escarificação e imersão em água (0, 12, 24 e 48 horas) e em GA3 (0, 500, 1000 e 1500 mg L-1), a escarificação em um lote das sementes foi feita com lixa de nº 100. A sarcotesta das sementes de todos experimentos foi retirada utilizando a pre... (Resumo completo, clicar acesso eletrônico abaixo) / Mestre
8

The effect of scarification, temperature and light conditions on seed germination of Artemisia afra jacq. Ex willd.

Letsoalo, Mmakoma Mendy January 2022 (has links)
Thesis (M.A. Agricultural Management (Plant Production)) -- University of Limpopo, 2022 / Artemisia afra Jacq. ex Willd is a common medicinal plant in Africa belonging to the Asteraceae plant family. It has been used for decades as a treatment for cold related illnesses and a variety of other ailments such as asthma, malaria and kidney disorders. As such this has led to its high demand and it is faced with threats of overharvesting. As the plant is naturally occurring and not widely cultivated, it’s seed biology and germination properties are not documented. The optimum requirements (temperature and photoperiod) for seed germination as well as the effects of Moringa based biostimulant and different scarification methods were investigated on A. afra seeds in this study. The seeds were exposed to different scarification methods including physical scarification (rubbing using sandpaper), hot water soaking, cold water soaking, acid treatment (H2SO4) and fermentation (using effective microorganisms) while the untreated seeds served as the control under all conditions. Moringa based biostimulant was also used as a seed priming agent at 0, 0.5, 1 and 3% levels. The seeds were then placed under a variety of photoperiods including constant light, alternating light (16/8 hours) and continuous darkness at different temperatures (15°C, 25°C and 35°C). Germination percentages and mean germination time (MGT) were calculated from the results and Statistix 10.0 software was used at the probability level of 5%, to compare the mean values. It was observed that under the different temperatures without any other treatments, the highest germination rate (70%) was achieved at a 25°C. No germination (0%) was obtained at both 15°C and 35°C in all the experiments including scarification methods and photoperiods. Under the scarification treatments, soaking in hot and cold water scarification improved germination with final germination of 70%, compared to the other scarification methods (Physical at 20%, acid treatment at 20% and control at 10%). There was no germination observed (0%) for the fermented seeds in all the experiments. On the photoperiod treatments, the highest germination percentage of 70% was observed under alternating light condition. However, when mean germination time was calculated, continuous xiv darkness resulted in shortest MGT of 11 days compared to 13 days for both alternating light and for continuous light in this set of experiment. Seed priming with Moringa based biostimulant under alternating light conditions and at 25°C resulted in improved MGT. Under the investigated treatments, the use of 3% biostimulant exerted the highest improvement on germination with germination percentage of 62% and the shortest MGT of 7 days compared to the other treatments. Generally the final germination (%) and time of A. afra seeds were affected by scarification, temperature, light and priming using Moringa based biostimulant. The information generated from this study is important because it will contribute in bridging the scientific gap on the information that has never been documented on optimum requirements for effective propagation of A. afra through seeds. As such this information will be useful for small scale farmers and medicinal plant growers who are willing to recover the lost populations of A. afra through seed propagation thus improving their supply and income / National Research Foundation (NRF)
9

Morfologia e germinação de sementes de Syagrus oleracea (Mart.) Becc (Arecaceae)

Batista, Gisele Sales [UNESP] 24 July 2009 (has links) (PDF)
Made available in DSpace on 2014-06-11T19:28:30Z (GMT). No. of bitstreams: 0 Previous issue date: 2009-07-24Bitstream added on 2014-06-13T20:18:17Z : No. of bitstreams: 1 batista_gs_me_jabo.pdf: 457788 bytes, checksum: 8207da43ecec8840c20c419f1ab09bd5 (MD5) / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / A palmeira Syagrus oleracea (Mart.) Becc é a única espécie produtora de palmito amargo e desperta grande interesse no paisagismo brasileiro, porém ainda é pouco estudada. A germinação lenta e desuniforme das sementes acarretam problemas na propagação dessa espécie, dificultando principalmente, a produção de mudas em escala comercial. Desta forma, o objetivo deste trabalho foi descrever os aspectos morfológicos dos diásporos e das plântulas, bem como, estudar o efeito do substrato e da escarificação mecânica na germinação de sementes de S. oleracea. Para os estudos da morfologia, efetuou-se a semeadura de 100 diásporos em caixas de plástico (50 x 22 x 16 cm), contendo uma camada de 10 cm do substrato vermiculita média umedecida, sendo retiradas amostras representativas de casa fase do processo germinativo. As amostras, a face externa, interna e o embrião dos diásporos foram documentados com auxílio de câmara clara acoplada ao estereomicroscópio. Para o estudo do efeito do substrato e da escarificação mecânica, o delineamento foi inteiramente casualizado em esquema fatorial 6X2 (seis substratos: vermiculita, areia, Plantmax®, Turfa®, fibra de coco e composto de poda de árvore, combinados sem ou com escarificação mecânica do endocarpo) e 4 repetições de 25 diásporos. Anotou-se, a cada 5 dias, durante 90 dias, o número de sementes germinadas adotando como critério de germinação o aparecimento da primeira folha. Determinou-se porcentagem de germinação (%), Índice de Velocidade de Emergência (IVE), área foliar (cm2), comprimento de raiz (cm), massa seca de folha (g) e massa seca de raiz (g). As médias foram comparadas pelo teste de Tukey, a 5 %. Verificou-se que as sementes são albuminosas, com endosperma ruminado e de consistência dura ocupando quase todo o interior do diásporo; o embrião... / The Syagrus oleracea (Mart.) Becc palm is the only species producer of bitter palm heart and arouses great interest in the Brazilian landscape, but is still little studied. The slow and uneven germination of seeds cause problems in the propagation of this species, mainly the seedlings production on a commercial scale. The objective of this study was to describe the disseminule and seedling morphology and to study the effect of substrate and mechanical scarification on germination of S. oleracea seed. For study the morphology, was made the sowing of 100 disseminules in plastic boxes (50 x 22 x 16 cm) containing a layer of 10 cm medium vermiculite and samples representing each phase of the germination process. The samples, the external and internal face, and embryo of the seeds were documented using the help of a clear camera coupled to a stereomicroscope. For study the effect of substrate and mechanical scarification, the design was completely randomized in factorial scheme (6x2) with 4 replications of 25 disseminules. Noted to every 5 days during 90 days the number of germinated seed adopting as criterion for germination the appearance of the first leaf. It was determined percentage of germination (%), speed of emergence index (IVE), leaf area (cm2), root length (cm), leaf dry mass (g) and root dry mass (g). The averages were compared by Tukey test at 5%. The results showed that the seeds are albuminous type, ruminal endosperm with hard consistency occupying almost the entire interior of the disseminule; the embryo is lateral, peripheral, straight and little differentiated; the seed germination is remote tubular type. It was concluded that seeds without scarification in vermiculite, germinated faster and had higher percentage of germination (65%) and greater length of root (16.55 cm), leaf dry mass (5.07 g) and dry mass root (12.41 g).
10

Morfologia e germinação de sementes de Syagrus oleracea (Mart.) Becc (Arecaceae) /

Batista, Gisele Sales. January 2009 (has links)
Orientadora: Kathia Fernandes Lopes Pivetta / Banca: Regina Maria Monteiro de Castilho / Banca: Fabíola Vitti Moro / Resumo: A palmeira Syagrus oleracea (Mart.) Becc é a única espécie produtora de palmito amargo e desperta grande interesse no paisagismo brasileiro, porém ainda é pouco estudada. A germinação lenta e desuniforme das sementes acarretam problemas na propagação dessa espécie, dificultando principalmente, a produção de mudas em escala comercial. Desta forma, o objetivo deste trabalho foi descrever os aspectos morfológicos dos diásporos e das plântulas, bem como, estudar o efeito do substrato e da escarificação mecânica na germinação de sementes de S. oleracea. Para os estudos da morfologia, efetuou-se a semeadura de 100 diásporos em caixas de plástico (50 x 22 x 16 cm), contendo uma camada de 10 cm do substrato vermiculita média umedecida, sendo retiradas amostras representativas de casa fase do processo germinativo. As amostras, a face externa, interna e o embrião dos diásporos foram documentados com auxílio de câmara clara acoplada ao estereomicroscópio. Para o estudo do efeito do substrato e da escarificação mecânica, o delineamento foi inteiramente casualizado em esquema fatorial 6X2 (seis substratos: vermiculita, areia, Plantmax®, Turfa®, fibra de coco e composto de poda de árvore, combinados sem ou com escarificação mecânica do endocarpo) e 4 repetições de 25 diásporos. Anotou-se, a cada 5 dias, durante 90 dias, o número de sementes germinadas adotando como critério de germinação o aparecimento da primeira folha. Determinou-se porcentagem de germinação (%), Índice de Velocidade de Emergência (IVE), área foliar (cm2), comprimento de raiz (cm), massa seca de folha (g) e massa seca de raiz (g). As médias foram comparadas pelo teste de Tukey, a 5 %. Verificou-se que as sementes são albuminosas, com endosperma ruminado e de consistência dura ocupando quase todo o interior do diásporo; o embrião... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: The Syagrus oleracea (Mart.) Becc palm is the only species producer of bitter palm heart and arouses great interest in the Brazilian landscape, but is still little studied. The slow and uneven germination of seeds cause problems in the propagation of this species, mainly the seedlings production on a commercial scale. The objective of this study was to describe the disseminule and seedling morphology and to study the effect of substrate and mechanical scarification on germination of S. oleracea seed. For study the morphology, was made the sowing of 100 disseminules in plastic boxes (50 x 22 x 16 cm) containing a layer of 10 cm medium vermiculite and samples representing each phase of the germination process. The samples, the external and internal face, and embryo of the seeds were documented using the help of a clear camera coupled to a stereomicroscope. For study the effect of substrate and mechanical scarification, the design was completely randomized in factorial scheme (6x2) with 4 replications of 25 disseminules. Noted to every 5 days during 90 days the number of germinated seed adopting as criterion for germination the appearance of the first leaf. It was determined percentage of germination (%), speed of emergence index (IVE), leaf area (cm2), root length (cm), leaf dry mass (g) and root dry mass (g). The averages were compared by Tukey test at 5%. The results showed that the seeds are albuminous type, ruminal endosperm with hard consistency occupying almost the entire interior of the disseminule; the embryo is lateral, peripheral, straight and little differentiated; the seed germination is remote tubular type. It was concluded that seeds without scarification in vermiculite, germinated faster and had higher percentage of germination (65%) and greater length of root (16.55 cm), leaf dry mass (5.07 g) and dry mass root (12.41 g). / Mestre

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