• Refine Query
  • Source
  • Publication year
  • to
  • Language
  • 166
  • 143
  • 44
  • 16
  • 4
  • 4
  • 4
  • 4
  • 4
  • 4
  • 3
  • 3
  • 2
  • 2
  • 2
  • Tagged with
  • 441
  • 123
  • 73
  • 61
  • 59
  • 59
  • 47
  • 42
  • 42
  • 41
  • 34
  • 34
  • 34
  • 34
  • 32
  • 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.
91

Seed and seedling disease of corn and soybean in Ohio the role of Fusarium graminearum, Pythium species diversity, fungicide sensitivity, Pythium community composition, and soil properties in disease severity /

Broders, Kirk Dale. January 2008 (has links)
Thesis (Ph. D.)--Ohio State University, 2008. / Title from first page of PDF file. Includes bibliographical references (p. 176-187).
92

Functional and genetic analysis of plant transcription factors involved in the plant growth under various environmental conditions

Yuan, Kun, Wysocka-Diller, Joanna, Singh, Narendra K., January 2008 (has links) (PDF)
Thesis (Ph. D.)--Auburn University, 2008. / Abstract. Vita. Includes bibliographical references.
93

Comparative anatomy and morphology of embryos and seedlings of maize, oats, and wheat

Avery, George S. January 1900 (has links)
Presented as Thesis (Ph. D.)--University of Wisconsin--Madison, 1927. / "Reprinted ... from the Botanical gazette, Vol. LXXXIX, no. I, March 1930." Includes bibliographical references (p. 38-39).
94

Seletividade de tratamentos herbicidas em mudas pré-brotadas de cana-de-açúcar CTC14 /

Garcia, Mirela Peroni. January 2016 (has links)
Orientador: Pedro Luís da Costa Aguiar Alves / Banca: Marcos Antonio Kuva / Banca: Mariluce Pascoina Nepomuceno / Resumo: Um novo sistema de plantio de cana-de-açúcar, utilizando mudas-pré-brotadas (MPB) em substituição aos fragmentos de colmos de cana fundamenta a hipótese deste trabalho de que poderá haver intoxicação nas mudas pelos herbicidas que são aplicados em pré emergência da cultura no sistema tradicional. Portanto, objetivou-se neste estudo verificar a seletividade de tratamentos de herbicidas aplicados em pré-plantio da MPB de cana-de-açúcar. Foi realizado um experimento a campo, no delineamento em blocos casualizados, utilizando sete tratamentos (T1: 720 g i.a.ha-1 oxifluorfen + 600 g i.a.ha-1 sulfentrazone; T2: 720 g i.a. ha-1oxifluorfen + 2500 g i.a. ha-1 atrazina; T3: 1100 g i.a. ha-1 tebutiuron + 600 g i.a. ha-1 sulfentrazone; T4: 1920g i.a. ha-1 s-metolaclor + 600g i.a. ha-1sulfentrazone; T5: 1008 g i.a. ha-1 clomazone + 2500 g i.a. ha-1 atrazina; T6: 1080 g i.a. ha-1 clomazone + 600 g i.a. ha-1 sulfentrazone; T7: testemunha capinada) em 4 repetições, na cultivar CTC14. Após a sulcação, foi realizada a pulverização dos herbicidas e, após 24 horas, o plantio das mudas. No início do desenvolvimento das mudas todos os tratamentos com herbicida causaram fitointoxicação, mas com o crescimento e desenvolvimento das mudas os sintomas foram diminuindo, não havendo diferença de altura, diâmetro de colmos, número de folhas, eficiência quântica do FII (Fv/Fm) e matéria seca das plantas entre os tratamentos como, também, na produtividade e características tecnológicas dos colmos não houve ... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: A new sugarcane planting system, using seedlings, pre-sprouted (MPB) to replace the cane stalks substantiates the hypothesis of this study that there might be intoxication the seedlings by herbicides that are sprayed in pre emergence of the crop in traditional system. Therefore, the aim of this work was to study the selectivity of herbicides treatments applied in pre-planting "MPB" sugarcane. An experiment in the field was conducted in a randomized block design, using seven treatments (T1: 720 g i.a. ha-1 oxifluorfen + 600 g i.a. ha-1 sulfentrazone; T2: 720 g i.a.ha-1 oxifluorfen + 2500 g i.a. ha-1 atrazina; T3: 1100 g i.a. ha-1 tebutiuron + 600 g i.a. ha-1 sulfentrazone; T4: 1920 g i.a. ha-1 s-metolaclor + 600 g i.a. ha-1 sulfentrazone; T5: 1008 g i.a. ha-1 clomazone + 2500 g i.a. ha-1 atrazina; T6: 1080 g i.a. ha-1 clomazone + 600 g i.a. ha-1 sulfentrazone; T7: weeded control) in 4 replications in a commercial variety, CTC14. After furrow herbicides were sprayed and 24 hours after, planting the seedlings. Early in the development of seedlings all herbicide treatments showed phytotoxicity, but with the growth and development of culture the symptoms have diminished, with no height difference, stalk diameter, number of leaves, quantum efficiency of FII (Fv / Fm) and dry matter, between the treatments and in the harvest, there was no significant difference between the average productivity and technological characteristics to the stalks. All herbicides treatments were selective when applied in pre-planting to "MPB" system / Mestre
95

Avaliação de tubetes biodegradáveis para a produção de Petúnia-Comum (Petúnia x hybrida) /

Ferraz, Marcelo Vieira. January 2006 (has links)
Orientador: Marney Pascoli Cereda / Banca: Olivier F. Vilpoux / Banca: Magali Ribeiro da Silva / Banca: Simone Damasceno / Banca: Denise Laschi / Resumo: A demanda atual de plantas ornamentais e flores no Brasil ainda é muito baixa quando comparada aos valores consumidos em países do primeiro mundo. Enquanto um brasileiro gasta em média US$ 6,00/ano, um norueguês consome US$ 143,00/ano. O mercado de plantas ornamentais e flores no país vêm crescendo muito nos últimos anos. Para verificar o potencial de uso de recipientes biodegradáveis um experimento foi conduzido na área experimental do Departamento de Recursos Naturais/Ciências Florestais na Fazenda Experimental Lageado da Faculdade de Ciências Agronômicas da UNESP de Botucatu-SP. O experimento teve início em 09/08/04 e término no 22/09/04. Segundo os dados da estação metereológica da UNESP de Botucatu, SP, os meses de agosto e setembro apresentaram em ambiente externo temperatura mínima de 13,18ºC a 17,00ºC; temperatura máxima de 25,01ºC a 29,86ºC; temperatura média de 17,6ºC a 21,84ºC e umidade relativa de 45,38% a 46,53%, respectivamente. Inicialmente o experimento foi conduzido no interior de estufa (A) com controle de umidade relativa, que era coberta com tela de sombreamento de 50%. Para registro da temperatura no interior da estufa (A), foi usado termômetro de máxima e mínima do tipo capela (plástico). A estufa (B) tinha um agrofilme transparente de 150 micra para proteção das mudas, não havendo controle de temperatura e umidade relativa, foram utilizados termômetro de máxima e mínima do tipo capela (plástico) e higrômetro de leitura direta (plástico). Os recipientes usados para formação das mudas foram saquinhos plásticos de polietileno na cor preta (tradicionais) e tubetes biodegradáveis. Os saquinhos plásticos tinham 0,60 micra de espessura, nas dimensões de 10,00 cm de comprimento, 5,00 cm de diâmetro, correspondendo a 196,25 cm3 de volume sendo a parte interna completamente lisa... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: The current demand of ornamental plants and flowers in Brazil is still very low when it is compared with the consumed values of development. While one Brazilian spends US$ 6,00 per year, one Norwegian consumes US$ 143,00. The market of ornamental plants and flowers in the country have been growing a lot in recent years. To verify the potencial of biodegradable containers an experiment was lead in the experimental area of the Department of Forest Sciences in Lageado Experimental Farm of the Agronomic Science College of UNESP in Botucatu-SP. The experiment have started in 09/08/04 and ended in 22/09/04. According to the metereológical station of the UNESP of Botucatu, SP, the months of August and September had presented in external environment minimum temperature of 13,18ºC to 17,00ºC; maximum temperature of 25,01ºC to 29,86ºC; average temperature of 17,6ºC to 21,84ºC and relative humidity of 45,38% to 46,53%, respectively. Initially the experiment was lead inner a greenhouse (A), that was covered with screen of shadow of 50%. For register of the temperature in the interior of the greenhouse (A), with 5 control of relative humidity, it was used thermometer of maximum and minimum of the type chapel (plastic) The greenhouse (B) had one agrofilm transparent of 150 micra for protection of the seedlings, not having temperature control and relative humidity, thermometer of maximum and minimum of the type chapel (plastic) and higrômeter of direct reading had been used (plastic).The containers used for the growth of the plants were small black bags of polyethylene (traditional ones) and biodegradable containers. The small black bags had 0,60 micra of thickness, in the dimensions of 10,0 cm of length and 5,0 cm of diameter, with a 196,25 cm3 volume, smooth in the internal wall... (Complete abstract, click electronic access below) / Doutor
96

Qualidade de muda e desenvolvimento final a campo de abobrinha e beterraba a partir de diferentes substratos e bandejas

Farinacio, Dione January 2011 (has links)
A região Sudoeste do Paraná se caracteriza por apresentar no meio rural significativa participação de agricultores familiares. Nesse contexto, a olericultura tem se destacado como importante alternativa de renda para estes agricultores e, assim, reveste-se de importância para a região. Entretanto, para que esta atividade desenvolva todo seu potencial, é preciso desenvolver tecnologias adaptadas às condições locais, especialmente no sentido de reduzir a dependência de insumos externos e de reduzir os custos de produção. Nesse sentido, propôs-se o presente estudo com vistas a avaliar a produção de mudas de abobrinha e de beterraba em recipientes coletivos e a produção das culturas implantadas com estas mudas, como alternativa à semeadura direta nos próprios canteiros normalmente empregada na região. O trabalho foi desenvolvido na UTFPR – Campus Pato Branco, com a utilização de diferentes substratos formulados com resíduo de carvão, húmus e vermiculita, misturados em diferentes proporções, tendo como testemunha o substrato comercial Húmus Fértil®, acondicionados em bandejas de 128 e 200 células. O estudo envolveu a realização de quatro experimentos, sendo que no primeiro avaliou-se a qualidade das mudas de abobrinha produzidas com estes substratos e bandejas; no segundo, avaliou-se a produção de mudas de beterraba incluindo a semeadura direta como testemunha; no terceiro, avaliou-se a produção de abobrinha a partir das mudas obtidas no primeiro experimento; e, no quarto experimento, avaliou-se a produção de beterraba. Nos experimentos 01 e 03, inicialmente, foram avaliadas a porcentagem de emergência e o índice de velocidade de emergência. Depois, aos 30 dias após a semeadura, as mudas foram avaliadas pelas variáveis altura da planta, diâmetro do caule, número de folhas, área foliar, fitomassa fresca e seca da parte aérea e do sistema radicular. Para os experimentos 02 e 04, o transplantio ocorreu 30 dias após a semeadura. No experimento 02, os frutos de abobrinha foram colhidos quando atingiram o ponto de comercialização (comprimento de 15 a 20 cm), colhendo-os a cada dois dias, até que finalizasse a produção. Avaliaram-se as variáveis diâmetro do fruto, número de frutos e produção total de frutos (expressa em Mg ha-1). No experimento 04, as avaliações foram realizadas aos 55 dias após o transplantio, determinando-se a altura da planta, o número de folhas, a área foliar e fitomassa seca da parte aérea, o diâmetro e o peso das raizes tuberosas. Os resultados obtidos permitem concluir que as características químicas dos substratos influenciaram significativamente a qualidade das mudas produzidas, especialmente o pH e a relação álcio/magnésio no caso da abobrinha, e o teor de Mn e a relação fósforo/zinco, no caso da beterraba. Observou-se, ainda, que o volume de substrato utilizado na produção das mudas interferiu significativamente sobre a qualidade das mudas produzidas, sendo que a bandeja de 128 células (volume maior) produziu mudas de melhor qualidade que a bandeja de 200 células. A qualidade da muda utilizada afetou significativamente a produtividade da cultura sendo que no caso da abobrinha observou-se produtividade entre 7,9 e 24,1 Mg ha-1 e, no caso da beterraba, entre 22,3 e 59,0 Mg ha-1. / The Southwest Parana region is characterized by presenting the significant participation of family farmers. In this context, horticulture has emerged as an important alternative source of income for these farmers, and thus is of importance to the region. However, for this activity to evelop their full potential, we must develop technologies suited to local conditions, particularly to reduce dependence on external inputs and to reduce production costs. In this sense, it was proposed this study in order to evaluate the production of seedlings of zucchini and beet on trays and the production of crops with these seedlings implanted as an alternative to direct sowing in their own beds usually employed in the region. The experiment was carried at UTFPR – campus Pato Branco, with the use of different substrates formulated on the waste coal, humus and vermiculite mixed in different proportions, and as shown by the commercial substrate Húmus Fertil®, packed in trays of 128 and 200 cells. The study involved the performance of four experiments, and at first we evaluated the quality of seedlings of zucchini grown with these substrates and pans, in the second evaluated the production of beet seedlings including direct seeding as a witness, in the third, evaluated the production of squash seedlings from the first experiment, and in the fourth experiment, we evaluated the production of sugar beet. In experiments 01 and 03 were initially evaluated the percentage of emergence speed rate of emergence. Then at 30 days after sowing, the seedlings were evaluated for the variables plant height, stem diameter, leaf number, leaf area, fresh and dry biomass of shoots and roots. For the trials 02 and 04, the transplant was done 30 days after sowing. In experiment 02, the fruits of zucchini were harvested when they reached the point of sale (length 15-20 cm), harvesting them every two days until finalize the production. We evaluated the variables: the diameter of the fruit, fruit number and total yield (in Mg ha-1). In experiment 04, were examined 55 days after transplanting, determining plant height, leaf number, leaf area and dry weight of shoots, the diameter and the weight of tuberous roots. The results showed that the chemical characteristics of substrates significantly influenced the quality of plants, especially the pH and the calcium/magnesium in the case of zucchini, and the ratio of manganese and phosphorus/zinc, in the case of beet. It was noted also that the volume of substrate used in the nursery significantly affect the quality of plants, and the 128 trays (larger volume) produced seedlings of better quality than the tray 2001 cells. The quality of the switches used significantly affected the yield and in the case of zucchini yield was observed between 7,9 and 24,1 Mg ha-1 and in the case of beet, between 22,3 and 59,0 Mg ha-1.
97

Qualidade de muda e desenvolvimento final a campo de abobrinha e beterraba a partir de diferentes substratos e bandejas

Farinacio, Dione January 2011 (has links)
A região Sudoeste do Paraná se caracteriza por apresentar no meio rural significativa participação de agricultores familiares. Nesse contexto, a olericultura tem se destacado como importante alternativa de renda para estes agricultores e, assim, reveste-se de importância para a região. Entretanto, para que esta atividade desenvolva todo seu potencial, é preciso desenvolver tecnologias adaptadas às condições locais, especialmente no sentido de reduzir a dependência de insumos externos e de reduzir os custos de produção. Nesse sentido, propôs-se o presente estudo com vistas a avaliar a produção de mudas de abobrinha e de beterraba em recipientes coletivos e a produção das culturas implantadas com estas mudas, como alternativa à semeadura direta nos próprios canteiros normalmente empregada na região. O trabalho foi desenvolvido na UTFPR – Campus Pato Branco, com a utilização de diferentes substratos formulados com resíduo de carvão, húmus e vermiculita, misturados em diferentes proporções, tendo como testemunha o substrato comercial Húmus Fértil®, acondicionados em bandejas de 128 e 200 células. O estudo envolveu a realização de quatro experimentos, sendo que no primeiro avaliou-se a qualidade das mudas de abobrinha produzidas com estes substratos e bandejas; no segundo, avaliou-se a produção de mudas de beterraba incluindo a semeadura direta como testemunha; no terceiro, avaliou-se a produção de abobrinha a partir das mudas obtidas no primeiro experimento; e, no quarto experimento, avaliou-se a produção de beterraba. Nos experimentos 01 e 03, inicialmente, foram avaliadas a porcentagem de emergência e o índice de velocidade de emergência. Depois, aos 30 dias após a semeadura, as mudas foram avaliadas pelas variáveis altura da planta, diâmetro do caule, número de folhas, área foliar, fitomassa fresca e seca da parte aérea e do sistema radicular. Para os experimentos 02 e 04, o transplantio ocorreu 30 dias após a semeadura. No experimento 02, os frutos de abobrinha foram colhidos quando atingiram o ponto de comercialização (comprimento de 15 a 20 cm), colhendo-os a cada dois dias, até que finalizasse a produção. Avaliaram-se as variáveis diâmetro do fruto, número de frutos e produção total de frutos (expressa em Mg ha-1). No experimento 04, as avaliações foram realizadas aos 55 dias após o transplantio, determinando-se a altura da planta, o número de folhas, a área foliar e fitomassa seca da parte aérea, o diâmetro e o peso das raizes tuberosas. Os resultados obtidos permitem concluir que as características químicas dos substratos influenciaram significativamente a qualidade das mudas produzidas, especialmente o pH e a relação álcio/magnésio no caso da abobrinha, e o teor de Mn e a relação fósforo/zinco, no caso da beterraba. Observou-se, ainda, que o volume de substrato utilizado na produção das mudas interferiu significativamente sobre a qualidade das mudas produzidas, sendo que a bandeja de 128 células (volume maior) produziu mudas de melhor qualidade que a bandeja de 200 células. A qualidade da muda utilizada afetou significativamente a produtividade da cultura sendo que no caso da abobrinha observou-se produtividade entre 7,9 e 24,1 Mg ha-1 e, no caso da beterraba, entre 22,3 e 59,0 Mg ha-1. / The Southwest Parana region is characterized by presenting the significant participation of family farmers. In this context, horticulture has emerged as an important alternative source of income for these farmers, and thus is of importance to the region. However, for this activity to evelop their full potential, we must develop technologies suited to local conditions, particularly to reduce dependence on external inputs and to reduce production costs. In this sense, it was proposed this study in order to evaluate the production of seedlings of zucchini and beet on trays and the production of crops with these seedlings implanted as an alternative to direct sowing in their own beds usually employed in the region. The experiment was carried at UTFPR – campus Pato Branco, with the use of different substrates formulated on the waste coal, humus and vermiculite mixed in different proportions, and as shown by the commercial substrate Húmus Fertil®, packed in trays of 128 and 200 cells. The study involved the performance of four experiments, and at first we evaluated the quality of seedlings of zucchini grown with these substrates and pans, in the second evaluated the production of beet seedlings including direct seeding as a witness, in the third, evaluated the production of squash seedlings from the first experiment, and in the fourth experiment, we evaluated the production of sugar beet. In experiments 01 and 03 were initially evaluated the percentage of emergence speed rate of emergence. Then at 30 days after sowing, the seedlings were evaluated for the variables plant height, stem diameter, leaf number, leaf area, fresh and dry biomass of shoots and roots. For the trials 02 and 04, the transplant was done 30 days after sowing. In experiment 02, the fruits of zucchini were harvested when they reached the point of sale (length 15-20 cm), harvesting them every two days until finalize the production. We evaluated the variables: the diameter of the fruit, fruit number and total yield (in Mg ha-1). In experiment 04, were examined 55 days after transplanting, determining plant height, leaf number, leaf area and dry weight of shoots, the diameter and the weight of tuberous roots. The results showed that the chemical characteristics of substrates significantly influenced the quality of plants, especially the pH and the calcium/magnesium in the case of zucchini, and the ratio of manganese and phosphorus/zinc, in the case of beet. It was noted also that the volume of substrate used in the nursery significantly affect the quality of plants, and the 128 trays (larger volume) produced seedlings of better quality than the tray 2001 cells. The quality of the switches used significantly affected the yield and in the case of zucchini yield was observed between 7,9 and 24,1 Mg ha-1 and in the case of beet, between 22,3 and 59,0 Mg ha-1.
98

Regeneration of the forest after logging at Kintap, South Kalimantan, Indonesia

Jafarsidik, Yusuf January 1998 (has links)
No description available.
99

Molecular characterization and regulation of embryogenesis-associated genes in Douglas-fir (Pseudotsuga menziesii [Mirb.] Franco)

Chatthai, Malinee 21 December 2017 (has links)
As a direct approach to investigate the molecular basis of embryogenesis in Douglas-fir (Pseudotsuga menziesii [Mirb.] Franco), a cDNA library made from poly(A)⁺ RNA of developing seeds was differentially screened for clones representing transcripts abundant in the developing seeds but absent in mature seeds. Of a number of clones isolated, two groups were selected for further sequence and gene expression analysis. A group of four cDNA clones (PM2S1, PM2S2, PM2S3 and PM2S4) shared a significant nucleotide and deduced amino acid sequence similarity with each other and with gymnosperm 2S seed storage protein cDNAs. The deduced amino acid sequences had low similarity with angiosperm 2S storage proteins but contained all conserved cysteine residues in an arrangement suggestive of a structural similarity between the 2S seed storage proteins from gymnosperms and angiosperms. Northern blot analysis revealed PM2S mRNAs were present specifically in seeds and temporally during seed development. However, the relatively low abundance of PM2S3 mRNAs and the decline of PM2S2 mRNAs in megagametophyte which occurred before that of the other mRNAs suggested that their expression was regulated differentially. The accumulation of PM2S transcripts in megagametophyte started during the early embryogenesis and reached a peak before that in zygotic embryos. PM2S mRNAs were present in Douglas-fir somatic embryos at the same developmental stages as those in zygotic embryos, and ABA and osmoticum stress were necessary for the expression of PM2S genes in somatic embryos. Southern blot analysis of genomic DNA suggested that the Douglas-fir 2S seed protein genes consisted of at least two sub-families each including several gene members. A gene designated gPm2Sl was isolated and sequenced. A comparison of the upstream sequence of gPm2Sl with the promoters of known 2S storage protein genes did not reveal significant sequence similarity except the presence of RY-repeated element (GCATGC), and the frequent occurrence of ACGT-containing motifs and E-box motifs (CANNTG). The 1.2-kb gPm2Sl promoter was fused to a P-glucuronidase (uidA) reporter gene and transformed into developing Douglas-fir seeds using particle bombardment and into tobacco via Agrobacterium tumefaciens. Histochemical analysis showed that the promoter was active in both systems and the gene expression was confined to endosperm and embryos of transgenic tobacco, indicating a common seed-specific regulatory mechanism between angiosperms and conifers. Another cDNA clone, PM2.1, hybridized to a 0.5 kb transcript and was predicted to encode a metallothionein (MT)-like protein. Alignment of the PM2.1 predicted amino acid sequence with other plant MT-like gene products revealed a general paucity of Cys and Cys-Xaa-Cys sequences and the presence of serine residues within the conserved Cys-Xaa-Cys motifs in the C-terminal domain. Phylogenetic analysis showed that PM2.1 grouped with class I/type 3 MT-like genes. The PM2.1 was expressed in somatic and zygotic embryos, in megagametophyte, as well as in hormone- and metal-treated seeds and seedlings. The PM2.1 transcripts were detected in the needles of 10-week-old seedlings, but not the root tissue or mature pollen. The expression of the PM2.1 gene in embryos was dependent upon ABA and osmoticum and was differentially modulated by metals, suggesting that the PM2.1 gene product may play a role in the control of microelement availability during Douglas-fir seed development and germination. Southern blot analysis of genomic DNA suggested that the PM2.1 was encoded by a multigene family. Three genomic clones were isolated and one of these clones (gPmMTa) was cloned and sequenced. The sequence analysis of its 5'-flanking region identified a number of putative regulatory elements such as ACGT-containing motifs, metal-responsive element (TGCGCC) and ethylene-responsive elements (ATTTCAAA) which may be responsible for gene transcription. DNase I-footprinting experiments with nuclear extracts isolated from Douglas-fir megagametophyte identified two protein-protected sites, a 31-bp sequence locating in the -176/-146 region that contained two ACGT-core motifs, and a 12-bp sequence, 5'-TGCCACGGAAGG-3', of unknown function. To identify promoter regions responsible for the regulation of gPmMTa gene expression, a series of deletions in the 0.9-kb fragment of the gPmMTa promoter was fused to the uidA reporter gene and the chimeric gene constructs were assayed in Douglas-fir and transgenic tobacco. Transient expression assays in megagametophyte and zygotic embryos indicated that the sequence lying between -190 and +88 of gPmMTa was sufficient to drive the expression of the reporter gene and the 225-bp fragment (-677 to -453) contained sequences necessary for high level expression. The gPmMTa promoter was not active in the seeds of transgenic tobacco. / Graduate
100

Influence of chemical fertilizers on the survival and growth of planted Douglas fir in coastal British Columbia

Jakoy, Andrew Geza January 1965 (has links)
The experiments discussed in this thesis are part of a continuing research program testing the influences of chemical fertilizers on the survival, growth and cone production of Douglas fir in coastal British Columbia. This study was initiated in the early spring of 1963 by the Consolidated Mining and Smelting Company of Canada Limited, Trail, B. C, and the Faculty of Forestry of the University of British Columbia. The thesis summarizes the influence of several chemical fertilizers on the survival and growth of planted Douglas fir seedlings from the beginning of the study to the present date. During the first phase of this study, the responses of planted Douglas fir to chemical fertilization have been investigated by four experiments. The first experiment, a trial of slowly soluble fertilizers, was initiated at the end of April, 1963, at three locations: U.B.C. Campus nursery, and TS 3 and TS 32b in the U.B.C. Research Forest. In a split plot design arrangement, Magamp, Urea, Aqua humus, Cxamide, Thiourea, Sludge and a bark product were dumped into or mixed with the soil in the holes made for the planting of four size classes of Douglas fir seedlings. At the end of April, 1964, the trial of slowly soluble fertilizers was repeated on the same locations. This time, the response to three Magamp particle sizes (commercially distributed Magamp, Magamp -6+8, and Magamp -8+10) as well as Sludge, Uramite and Thiourea was tested. Additional information concerning survival of planted Douglas fir seedlings was obtained from the Tahsis Logging Company at Gold River, B. C, which, in 1963, carried out a similar experiment with the same slowly soluble fertilizers. In all cases, the use of more readily soluble sources of nitrogen resulted in excessive mortality. The climate in 1963 and 1961; substantially influenced the survival and growth of the fertilized seedlings. In the second experiment, the response of Douglas fir seedlings planted in 1953, 1956 and 1959 to ammonium nitrate was investigated in the U.B.C. Forest. Nitraprills was applied randomly at six levels (0 to 800 lb. of nitrogen par acre) to a total of 360 trees. Treatments were applied in May of 1963 and 1964 at the time of flushing of vegetative buds. To date, the fertilization has improved neither height growth nor diameter increment and has had no influence on cone production. The third experiment was initiated at the end of December, 1963, in the U.B.C. Campus greenhouse. A. six-factor experiment was designed to test the responses of 2+0 planted Douglas fir seedlings to Magamp and Mitraprills. The fourth experiment was planned to compare the effects of Magamp and Nitraprills on 2+0 planted Douglas fir seedlings in the field in the U.B.C. Research Forest during the summer of 1964. The results of the third and fourth experiments have proved that the slowly soluble Magamp is more advantageous to seedlings than is the rapidly soluble Nitraprills when both are applied at the time of planting. However, these analyses have shown limited advantage to using either fertilizer during planting. The studies of these fertilizers should be continued and extended to include other sources of slowly soluble nitrogen. / Forestry, Faculty of / Graduate

Page generated in 0.0447 seconds