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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.
21

Morfologia, biologia e fototropismo de Batrachedra nuciferae Hodges (Lepidoptera: Coleophoridae). / Morphology, biology and phototropism of batrachedra nuciferae hodges (lepidoptera: coleophoridae).

Soto, Saul Sanchez 09 March 2004 (has links)
Os objetivos do trabalho foram os de descrever a morfologia externa de Batrachedra nuciferae Hodges (ovo, larvas, pupas e adultos); determinar a duração e viabilidade das fases de ovo, larval, pré-pupal, pupal e adulta, número de ínstares, razão de crescimento, relação sexual, períodos de pré-oviposição e oviposição, e fecundidade da espécie criada em flores masculinas de coqueiro (Cocos nucifera L.), bem como avaliar o efeito de diferentes comprimentos de ondas eletromagnéticas sobre adultos visando o estabelecimento de um método de monitoramento desta praga. Os estudos foram conduzidos em laboratório. O ovo é ovalado com cório reticulado, semitranslúcido quando recém-colocado, tornando-se posteriormente amarelo-laranja. Largura: 0,4 ± 0,03 mm, altura: 0,1 ± 0,01 mm. A larva neonata apresenta cabeça preta e prognata; tórax e abdome amarelo claro ou ligeiramente esbranquiçado, falsas pernas nos segmentos abdominais 3, 4, 5, 6 e 10. Comprimento: 1,1 ± 0,12 mm; largura da cápsula cefálica: 0,2 ± 0,37 mm. Larva de último ínstar com cabeça marrom-escuro, com seis estematas; primeiro segmento torácico com escudo dorsal preto e com a região lateral e ventral pigmentada de escuro; segundo e terceiro segmentos torácicos e segmentos abdominais esbranquiçados ou rosáceos nas regiões dorsal e lateral; pernas torácicas esbranquiçadas. Comprimento: 6,5 ± 0,60 mm; largura: 1,2 ± 0,11 mm; largura da cápsula cefálica: 0,7 ± 0,05 mm. Pupa subcilíndrica; de coloração creme quando recém-formada, e marrom ligeiramente escura quando madura. A fenda genital está Os objetivos do trabalho foram os de descrever a morfologia externa de Batrachedra nuciferae Hodges (ovo, larvas, pupas e adultos); determinar a duração e viabilidade das fases de ovo, larval, pré-pupal, pupal e adulta, número de ínstares, razão de crescimento, relação sexual, períodos de pré-oviposição e oviposição, e fecundidade da espécie criada em flores masculinas de coqueiro (Cocos nucifera L.), bem como avaliar o efeito de diferentes comprimentos de ondas eletromagnéticas sobre adultos visando o estabelecimento de um método de monitoramento desta praga. Os estudos foram conduzidos em laboratório. O ovo é ovalado com cório reticulado, semitranslúcido quando recém-colocado, tornando-se posteriormente amarelo-laranja. Largura: 0,4 ± 0,03 mm, altura: 0,1 ± 0,01 mm. A larva neonata apresenta cabeça preta e prognata; tórax e abdome amarelo claro ou ligeiramente esbranquiçado, falsas pernas nos segmentos abdominais 3, 4, 5, 6 e 10. Comprimento: 1,1 ± 0,12 mm; largura da cápsula cefálica: 0,2 ± 0,37 mm. Larva de último ínstar com cabeça marrom-escuro, com seis estematas; primeiro segmento torácico com escudo dorsal preto e com a região lateral e ventral pigmentada de escuro; segundo e terceiro segmentos torácicos e segmentos abdominais esbranquiçados ou rosáceos nas regiões dorsal e lateral; pernas torácicas esbranquiçadas. Comprimento: 6,5 ± 0,60 mm; largura: 1,2 ± 0,11 mm; largura da cápsula cefálica: 0,7 ± 0,05 mm. Pupa subcilíndrica; de coloração creme quando recém-formada, e marrom ligeiramente escura quando madura. A fenda genital está localizada no oitavo segmento na fêmea, e no nono segmento no macho. Comprimento da fêmea: 5,5 ± 0,45 mm, largura: 1,2 ± 0,10 mm. Comprimento do macho 4,9 ± 0,30 mm, largura: 1,1 ± 0,08. Adulto de coloração geral amarelo pálido ou palha, com escamas escuras nos palpos labiais, terço distal das antenas, nas asas anteriores e pernas. Entre o fim do primeiro terço e início do segundo terço das asas anteriores existe sempre uma mancha escura de forma mais ou menos oval ou alongada disposta longitudinalmente, e no terço distal com freqüência aparecem cerca de oito manchas escuras irregulares localizadas nas margens. O ápice do abdome é truncado com escamas brancas na fêmea e de forma oval com pêlos brancos no macho. Envergadura da Fêmea: 10,7 ± 1,06 mm; do macho: 9,1 ± 0,88 mm. Sob condições de 25°C, 60% UR e 12 h fotofase, a duração das fases de ovo, lagarta, pré-pupa, pupa e adulto foi de 3,2 ± 0,2 dias, 9,2 ± 1,7 dias, 2,3 ± 0,8 dias, 7,5 ± 0,6 dias e 13,7 ± 2,5 dias, respectivamente. A viabilidade das fases imaturas foi de 100%, 85,4%, 95,7% e 97,7%, respectivamente. A fase larval apresentou três ínstares, sendo a média da razão de crescimento de 1,761 ± 0,003. A relação sexual de adultos foi de 1: 1,2 (♀: ♂), o período de pré-oviposição foi de 2,6 ± 1,1 dias e o de oviposição de 11,3 ± 2,3 dias, sendo a fecundidade de 31,5 ± 18,3 ovos por fêmea. Das ondas eletromagnéticas avaliadas, emitidas pelas lâmpadas fluorescentes Black Light Blue (F15T8-BLB), Black Light (F15T8-BL), Plant Light (F15T8-PL), Blue (F15T8-B), Gold (F15T8-GO) e Luz do Dia, as que mais atraíram os adultos foram as ondas ultra violetas (BLB e BL), entre as quais não houve diferença estatística significativa. / The aim of this work was to describe the outer morphology of Batrachedra nuciferae Hodges (egg, larvae, pupae and adults), to determine the duration and viability of the egg, larval, prepupal, pupal and adult stages, number of instars, growth ratio, sex ratio, preoviposition and oviposition periods, and fecundity of the species reared in male coconut (Cocos nucifera L.) flowers, as well as to evaluate the effect of different lengths of electromagnetic waves on adults in order to set a monitoring method to this pest. The studies were conducted in laboratory. The egg is oval-shaped with reticulate semitranslucid chorion, when newly laid, later becoming yellowish-orange. Width: 0.,4 ± 0.03 mm, height: 0.,1 ± 0.01 mm. The neonate larva has a black prognathous head, light yellow or slightly whitish thorax and abdomen, false legs in abdominal segments 3, 4, 5, 6 and 10. Length: 1.1 ± 0.12 mm; width of the cephalic capsule: 0.2 ± 0.37 mm. The last instar larva is dark-brown headed, with six stemmata; first thorax segment with a black dorsal shield and dark-pigmented lateral and ventral regions; whitish second and third thorax segments and abdominal segments or pinkish dorsal and lateral regions; whitish thorax legs. Length: 6.5 ± 0.60 mm; width: 1.2 ± 0,11 mm; Length of the cephalic capsule: 0.7 ± 0.05 mm. Subcylindrical pupa, beige-colored when newly formed and slightly dark brown when mature. The genital slash is located in the eighth segment in females and ninth in males. Female length: 5.5 ± 0.45 mm, width: 1.2 ± 0.10 mm. Male length: 4.9 ± 0.30 mm, width: 1.1 ± 0.08. Overall adult color is pale yellow or sand, with dark scaled in labial palpi, distal third of antennae, in fore wings and legs. Between the first third end and beginning of second third of anterior wings there is always a dark spot somewhat oval-shaped or elongated longitudinally, and on the distal third about eight irregular dark spots in the margins are often found. The top abdomen is truncated with white scales in females and is oval-shaped with white hairs in males. Female span: 10.7 ± 1,06 mm; male span: 9.1 ± 0.88 mm. Under 25°C, 60% RH and 12-hour photophase conditions, the duration of the egg, larva, prepupa, pupa and adult stages was 3.2 ± 0.2 days, 9.2 ± 1.7 days, 2.3 ± 0.8 days, 7.5 ± 0.6 days and 13.7 ± 2.5 days, respectively. The viability of the immature stages was 100%, 85.4%, 95.7% and 97.7%, respectively. The larval stage presented three instars, with mean growth ratio of 1.761 ± 0.003. The adult sex ratio was 1: 1.2 (♀: ♂), the period of preoviposition 2.6 ± 1.1 days and oviposition 11.3 ± 2.3 days, with fecundity of 31.5 ± 18.3 eggs per female. Regarding the evaluated electromagnetic waves emitted by fluorescent lamps Black Light Blue (F15T8-BLB), Black Light (F15T8-BL), Plant Light (F15T8-PL), Blue (F15T8-B), Gold (F15T8-GO) and Daylight, the more attractant to adults were the ultraviolet waves (BLB and BL), among which no significant statistical difference was found.
22

Morfologia, biologia e fototropismo de Batrachedra nuciferae Hodges (Lepidoptera: Coleophoridae). / Morphology, biology and phototropism of batrachedra nuciferae hodges (lepidoptera: coleophoridae).

Saul Sanchez Soto 09 March 2004 (has links)
Os objetivos do trabalho foram os de descrever a morfologia externa de Batrachedra nuciferae Hodges (ovo, larvas, pupas e adultos); determinar a duração e viabilidade das fases de ovo, larval, pré-pupal, pupal e adulta, número de ínstares, razão de crescimento, relação sexual, períodos de pré-oviposição e oviposição, e fecundidade da espécie criada em flores masculinas de coqueiro (Cocos nucifera L.), bem como avaliar o efeito de diferentes comprimentos de ondas eletromagnéticas sobre adultos visando o estabelecimento de um método de monitoramento desta praga. Os estudos foram conduzidos em laboratório. O ovo é ovalado com cório reticulado, semitranslúcido quando recém-colocado, tornando-se posteriormente amarelo-laranja. Largura: 0,4 ± 0,03 mm, altura: 0,1 ± 0,01 mm. A larva neonata apresenta cabeça preta e prognata; tórax e abdome amarelo claro ou ligeiramente esbranquiçado, falsas pernas nos segmentos abdominais 3, 4, 5, 6 e 10. Comprimento: 1,1 ± 0,12 mm; largura da cápsula cefálica: 0,2 ± 0,37 mm. Larva de último ínstar com cabeça marrom-escuro, com seis estematas; primeiro segmento torácico com escudo dorsal preto e com a região lateral e ventral pigmentada de escuro; segundo e terceiro segmentos torácicos e segmentos abdominais esbranquiçados ou rosáceos nas regiões dorsal e lateral; pernas torácicas esbranquiçadas. Comprimento: 6,5 ± 0,60 mm; largura: 1,2 ± 0,11 mm; largura da cápsula cefálica: 0,7 ± 0,05 mm. Pupa subcilíndrica; de coloração creme quando recém-formada, e marrom ligeiramente escura quando madura. A fenda genital está Os objetivos do trabalho foram os de descrever a morfologia externa de Batrachedra nuciferae Hodges (ovo, larvas, pupas e adultos); determinar a duração e viabilidade das fases de ovo, larval, pré-pupal, pupal e adulta, número de ínstares, razão de crescimento, relação sexual, períodos de pré-oviposição e oviposição, e fecundidade da espécie criada em flores masculinas de coqueiro (Cocos nucifera L.), bem como avaliar o efeito de diferentes comprimentos de ondas eletromagnéticas sobre adultos visando o estabelecimento de um método de monitoramento desta praga. Os estudos foram conduzidos em laboratório. O ovo é ovalado com cório reticulado, semitranslúcido quando recém-colocado, tornando-se posteriormente amarelo-laranja. Largura: 0,4 ± 0,03 mm, altura: 0,1 ± 0,01 mm. A larva neonata apresenta cabeça preta e prognata; tórax e abdome amarelo claro ou ligeiramente esbranquiçado, falsas pernas nos segmentos abdominais 3, 4, 5, 6 e 10. Comprimento: 1,1 ± 0,12 mm; largura da cápsula cefálica: 0,2 ± 0,37 mm. Larva de último ínstar com cabeça marrom-escuro, com seis estematas; primeiro segmento torácico com escudo dorsal preto e com a região lateral e ventral pigmentada de escuro; segundo e terceiro segmentos torácicos e segmentos abdominais esbranquiçados ou rosáceos nas regiões dorsal e lateral; pernas torácicas esbranquiçadas. Comprimento: 6,5 ± 0,60 mm; largura: 1,2 ± 0,11 mm; largura da cápsula cefálica: 0,7 ± 0,05 mm. Pupa subcilíndrica; de coloração creme quando recém-formada, e marrom ligeiramente escura quando madura. A fenda genital está localizada no oitavo segmento na fêmea, e no nono segmento no macho. Comprimento da fêmea: 5,5 ± 0,45 mm, largura: 1,2 ± 0,10 mm. Comprimento do macho 4,9 ± 0,30 mm, largura: 1,1 ± 0,08. Adulto de coloração geral amarelo pálido ou palha, com escamas escuras nos palpos labiais, terço distal das antenas, nas asas anteriores e pernas. Entre o fim do primeiro terço e início do segundo terço das asas anteriores existe sempre uma mancha escura de forma mais ou menos oval ou alongada disposta longitudinalmente, e no terço distal com freqüência aparecem cerca de oito manchas escuras irregulares localizadas nas margens. O ápice do abdome é truncado com escamas brancas na fêmea e de forma oval com pêlos brancos no macho. Envergadura da Fêmea: 10,7 ± 1,06 mm; do macho: 9,1 ± 0,88 mm. Sob condições de 25°C, 60% UR e 12 h fotofase, a duração das fases de ovo, lagarta, pré-pupa, pupa e adulto foi de 3,2 ± 0,2 dias, 9,2 ± 1,7 dias, 2,3 ± 0,8 dias, 7,5 ± 0,6 dias e 13,7 ± 2,5 dias, respectivamente. A viabilidade das fases imaturas foi de 100%, 85,4%, 95,7% e 97,7%, respectivamente. A fase larval apresentou três ínstares, sendo a média da razão de crescimento de 1,761 ± 0,003. A relação sexual de adultos foi de 1: 1,2 (♀: ♂), o período de pré-oviposição foi de 2,6 ± 1,1 dias e o de oviposição de 11,3 ± 2,3 dias, sendo a fecundidade de 31,5 ± 18,3 ovos por fêmea. Das ondas eletromagnéticas avaliadas, emitidas pelas lâmpadas fluorescentes Black Light Blue (F15T8-BLB), Black Light (F15T8-BL), Plant Light (F15T8-PL), Blue (F15T8-B), Gold (F15T8-GO) e Luz do Dia, as que mais atraíram os adultos foram as ondas ultra violetas (BLB e BL), entre as quais não houve diferença estatística significativa. / The aim of this work was to describe the outer morphology of Batrachedra nuciferae Hodges (egg, larvae, pupae and adults), to determine the duration and viability of the egg, larval, prepupal, pupal and adult stages, number of instars, growth ratio, sex ratio, preoviposition and oviposition periods, and fecundity of the species reared in male coconut (Cocos nucifera L.) flowers, as well as to evaluate the effect of different lengths of electromagnetic waves on adults in order to set a monitoring method to this pest. The studies were conducted in laboratory. The egg is oval-shaped with reticulate semitranslucid chorion, when newly laid, later becoming yellowish-orange. Width: 0.,4 ± 0.03 mm, height: 0.,1 ± 0.01 mm. The neonate larva has a black prognathous head, light yellow or slightly whitish thorax and abdomen, false legs in abdominal segments 3, 4, 5, 6 and 10. Length: 1.1 ± 0.12 mm; width of the cephalic capsule: 0.2 ± 0.37 mm. The last instar larva is dark-brown headed, with six stemmata; first thorax segment with a black dorsal shield and dark-pigmented lateral and ventral regions; whitish second and third thorax segments and abdominal segments or pinkish dorsal and lateral regions; whitish thorax legs. Length: 6.5 ± 0.60 mm; width: 1.2 ± 0,11 mm; Length of the cephalic capsule: 0.7 ± 0.05 mm. Subcylindrical pupa, beige-colored when newly formed and slightly dark brown when mature. The genital slash is located in the eighth segment in females and ninth in males. Female length: 5.5 ± 0.45 mm, width: 1.2 ± 0.10 mm. Male length: 4.9 ± 0.30 mm, width: 1.1 ± 0.08. Overall adult color is pale yellow or sand, with dark scaled in labial palpi, distal third of antennae, in fore wings and legs. Between the first third end and beginning of second third of anterior wings there is always a dark spot somewhat oval-shaped or elongated longitudinally, and on the distal third about eight irregular dark spots in the margins are often found. The top abdomen is truncated with white scales in females and is oval-shaped with white hairs in males. Female span: 10.7 ± 1,06 mm; male span: 9.1 ± 0.88 mm. Under 25°C, 60% RH and 12-hour photophase conditions, the duration of the egg, larva, prepupa, pupa and adult stages was 3.2 ± 0.2 days, 9.2 ± 1.7 days, 2.3 ± 0.8 days, 7.5 ± 0.6 days and 13.7 ± 2.5 days, respectively. The viability of the immature stages was 100%, 85.4%, 95.7% and 97.7%, respectively. The larval stage presented three instars, with mean growth ratio of 1.761 ± 0.003. The adult sex ratio was 1: 1.2 (♀: ♂), the period of preoviposition 2.6 ± 1.1 days and oviposition 11.3 ± 2.3 days, with fecundity of 31.5 ± 18.3 eggs per female. Regarding the evaluated electromagnetic waves emitted by fluorescent lamps Black Light Blue (F15T8-BLB), Black Light (F15T8-BL), Plant Light (F15T8-PL), Blue (F15T8-B), Gold (F15T8-GO) and Daylight, the more attractant to adults were the ultraviolet waves (BLB and BL), among which no significant statistical difference was found.
23

The Phototropic Properties of Lactuca Ludoviciana (Nutt.) DC. and Silphium Laciniatum L.

Neal, George C. January 1941 (has links)
This paper deals with certain phases of phototropic properties of two exceptional plants, the pertinent behavior of each being decidedly individualistic and in remarkable contrast to that of herbaceous plants in general. The prickly lettuce, Lactuca ludoviciana (Nutt.) DC. and the rosinweed, Silphium laciniatum L., two common Denton County, Texas, plants, have been selected for this study.
24

Phototropism and Gravitropism in Transgenic Lines of Arabidopsis Altered in the Phytochrome Pathway

Hopkins, Jane A. 29 July 2011 (has links)
No description available.
25

Fotomorfogeneze: vliv světla na procesy vývoje rostlin ve výuce biologie na školách / Fotomorfogeneze: the effects of irradiation on plant development in the eductational programs of basic schools and highschools

Sedlecký, Libor January 2013 (has links)
The main aim of this diploma thesis was creation of functional experiments and supporting teaching materials for high school students which would clearly demonstrate the processes of photomorphogenesis in plants. Proposed experiments had to be verified in practice on the basis of their reliability, repeatability and reproducibility in schools. It was necessary to drew up the educational materials for each experiment focused on observation of photomorphogenesis plant's reactions. These materials give students the basics of scientific work and specifically they increase the interest in experimental plant biology. The first part of the thesis is literary introduction that provides the theoretical background to the topic of photomorphogenesis for teachers. It summarizes the current of the art mechanisms and manifestations of photomorphogenesis processes of plants. The second didactic part of the introduction deals with the framing up teaching of plant physiology into current curricula of education in the Czech Republic. For the formativ of educational materials experiments had to be designed to demonstrate reliably basic photomorphogenetical processes. Three experiments were designe dat: 1. plant phototropism, 2. negative plant phototropism and 3. plant scotomorphogenesis.To select these experiments I...
26

Modélisation téléonomique de la dynamique de croissance des plantes à partir du concept de densité foliairé / Spatial Leaf Density-based Modelling of Teleonomic Crown Dynamics for Crops and Trees

Beyer, Robert 15 September 2016 (has links)
Les modèles structure-fonction de la croissance des plantes (FSPMs) combinent la description du fonctionnement biophysique et du développement architectural des plantes. On peut distinguer deux grandes familles de FSPM : d'une part les modèles décrivant finement la structure de la plante au niveau de l'organe et d'autre part les modèles à plus grande échelle qui s'intéressent directement à la forme du houppier. La paramétrisation du premier type de modèle est souvent difficile car elle nécessite des données expérimentales très riches. A l'inverse, les modèles à plus grande échelle mettent généralement en œuvre des lois empiriques qui ne permettent pas de décrire la plasticité de la croissance, et l'adaptation de la plante à des conditions environnementales différentes.Pour répondre à ces problématiques, nous nous tournons vers un nouveau paradigme : Motivé par le succès du concept de la densité spatiale dans les modèles en écologie des populations, cette thèse caractérise la distribution spatiale de feuillage dans les plantes par la densité de surface foliaire , ce qui permet une description locale ouvrant la voie à une prise en compte de la plasticité des plantes, tout en ne décrivant pas chaque feuille individuellement, ce qui permet de modéliser des vieux et grands arbres, dont le nombre de feuilles est sinon trop lourd à gérer du point de vue des calculs. Cette thèse présente des modèles dynamiques de croissance développés spécifiquement pour les plantes agricoles et les arbres. Nous explorons des approches mathématiques différentes en temps discrète et continue, tout en examinant d'un œil critique leurs aptitudes conceptuelles ainsi que des possibilités de simplifications et de solutions analytiques dans l'optique de l'accélération des simulations.La densité foliaire permet le calcul de l'interception de lumière par la loi de Beer-Lambert et la production de biomasse grâce au concept d'efficience d'utilisation de la lumière. Le mécanisme central qui est considéré pour les différentes approches développées dans cette thèse est celui de l'expansion locale de la surface foliaire dans la direction du gradient de lumière. Par ce concept téléonomique, nous faisons l'hypothèse que la plante cherche par son développement à optimiser la productivité de la surface foliaire pour la production de biomasse. Ce principe induit ainsi un développement horizontal et vertical du feuillage vers l'extérieur du houppier. Le développement horizontal cesse quand on s'approche trop de plantes voisines, leur ombrage diminuant le gradient de lumière et donc l'expansion de densité de surface foliaire dans ces directions. Le modèle de production de biomasse est également généralisé pour une prise en compte explicite de la teneur en eau du sol en introduisant une composante hydraulique permettant de décrire l'équilibre mécaniste entre le potentiel hydrique dans les feuilles et la transpiration par la régulation stomatale. Finalement, nous prenons en compte l'allocation de biomasse produite à d'autres compartiments de la plante tels que les racines et le bois selon la théorie du « pipe model ».Les résultats des modèles sont comparés à un large jeu de données expérimentales sur des plantations à différentes densités et conditions environnementales. Celui-ci montre de remarquables capacités d'une part à prévoir les variables biométriques importantes (hauteur, diamètre du tronc) ainsi que certaines relations d'allométrie, et d'autre part à générer des formes de houppier en accord avec les formes observées, ceci pour les différents scénarios de compétition et comme propriété émergente du modèle. Ainsi, cette thèse démontre le potentiel du concept de densité de surface foliaire en modélisation de la croissance des plantes, par sa capacité à reproduire les comportements locaux et l'adaptation à des conditions environnementales variées sans compromettre l'efficacité et la robustesse. / Functional-structural plant growth models (FSPMs) have emerged as the synthesis of mechanistic process-based models, and geometry-focussed architectural models. In terms of spatial scale, these models can essentially be divided into small-scale models featuring a topologic­al architecture – often facing data-demanding parametrisations, parameter sensitivity, as well as computational heaviness, which imposes problematic limits to the age and size of in­dividuals than can be simulated – and large-scale models based on a description of crown shape in terms of rigid structures such as empirical crown envelopes – commonly strug­gling to allow for spatial variability and plasticity in crown structure and shape in response to local biotic or abiotic growth conditions.In response to these limitations, and motivated not least by the success-story of spatial density approaches in theoretical populations ecology, the spatial distribution of foliage in plants in this thesis is characterised in terms of spatial leaf density, which allows for a com­pletely local description that is a priori unrestricted in terms of plasticity, while being robust and computationally efficient. The thesis presents dynamic growth models specific­ally developed for crops and trees, exploring different mathematical frameworks in continu­ous and discrete time, while critically discussing their conceptual suitability and exploring analyt­ical simplifications and solutions to accelerate simulations.The law of Beer-Lambert on the passing of light though an absorbing medium allows to infer the local light conditions based on which local biomass production can be computed via a radiation use efficiency. A key unifying mechanism of the different models is the local ex­pansion of leaf density in the direction of the light gradient, which coincides with the direc­tion most promising with regard to future biomass productivity. This aspect falls into the line of teleonomic and optimization-oriented plant growth models, and allows to set aside the otherwise complex modelling of branching processes. The principle induces an expans­ive horizontal and upward-directed motion of foliage. Moreover, it mechanistically accounts for a slow-down of the horizontal expansion as soon as a neighbouring competitor's crown is reached, since the appropriate region is already shaded, implying a corresponding adapta­tion of the light gradient. This automatically results in narrower crowns in scenarios of in­creased competition, ultimately decreasing biomass production and future growth due to lesser amount of intercepted light. In an extension, the impact of water availability is incor­porated into the previously light-only dependency of biomass production by means of a novel hydraulic model describing the mechanistic balancing of leaf water potential and tran­spiration in the context of stomatal control. The allocation of produced biomass to other plant compartments such as roots and above-ground wood, e.g. by means of the pipe model theory, is readily coupled to leaf density dynamics.Simulation results are compared against a variety of empirical observations, ranging from long-term forest inventory data to laser-recorded spatial data, covering multiple abi­otic environmental conditions and growth resources as well as stand densities and thus de­grees of competition. The models generate a series of complex emergent properties includ­ing the realistic prediction of biometric growth parameters, the spontaneous adaptability and plasticity of crown morphologies in different competitive scenarios, the empirically documented insensitivity of height to stand density, the accurate deceleration of height growth, as well as popular allometric relationships – altogether demonstrating the potential of leaf density based approaches for efficient and robust plant growth modelling.
27

DIS1 AND DIS2 PLAY A ROLE IN TROPISMS IN ARABIDOPSIS THALIANA

Reboulet, James Christopher 19 August 2008 (has links)
No description available.
28

Molecular cloning of the soybean phototropins

Roy, Pallabi January 2014 (has links)
Indiana University-Purdue University Indianapolis (IUPUI) / The phototropin photoreceptors are important regulators of plant growth and development and can therefore affect the photosynthetic activity of plants. Phototropin1 and Phototropin2 are versatile protein kinases that become activated when exposed to blue light. Their photobiological actions are best understood in the model plant Arabidopsis thaliana, where they are known to trigger several responses to blue light, one of which is phototropism, the bending of plant organs towards light. Additionally, phot1 and phot2 drive stomatal opening, chloroplast arrangement in leaf cells, leaf expansion, and leaf orientation. The phot1-specific response is rapid inhibition of hypocotyl growth, leaf positioning and mRNA stability whereas phot2 mediates the chloroplast avoidance response to high light. These responses impact a plant’s ability to capture light for photosynthesis, therefore the phototropins play important roles in optimizing a plant’s photosynthetic activity. Soybean (Glycine max) is a very important crop plant in Indiana known for its nutritional versatility and is also utilized for biodiesel production.In spite of soybean being a key crop, there is currently no information about the functionality of soybean phototropins. Also, being a legume, soybean has many structural and functional features that are not present in Arabidopsis. Interestingly, PsPHOT1A (a photoreceptor from garden pea) was found to be a functional phototropin as it was able to complement the phot1 mutation in Arabidopsis. The roles of these proteins in soybean will be elucidated based on the hypothesis that soybean phototropins play essential roles in regulating photosynthetic activity as do the Arabidopsis phototropins. To date, five soybean phototropins, 3 PHOT1s and 2 PHOT2s, are believed to exist. These GmPHOT protein coding regions were amplified by RT-PCR and cloned into pCR8/TOPO or pENTR-D/TOPO vectors via TOPO cloning to utilize Gateway cloning technology to create plant transformation constructs subsequently. The cloned GmPHOT cDNAs from each of the 5 GmPHOTs were sequenced and compared to the GmPHOT sequences from the Phytozome database to assess the accuracy of the gene models. The gene models of all the GmPHOTs were found to be accurate except that of GmPHOT1B-2. The high level of sequence identity between the GmPHOTs and AtPHOTs and the conservation of LOV domains and catalytic domains indicate structural resemblance between them. This suggests that soybean phototropins should encode active photoreceptors. The cloned protein coding regions from soybean were then recombined into a plant expression vector via Gateway technology,which were then used for transformation of Agrobacterium tumefaciens. These plant expression constructs will be utilized in the future to determine the functionality of soybean phototropins in Arabidopsis.

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