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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.
31

Glycerol production by Dunaliella species in saline waste water treatment

Emmett, Robyn Angela January 1996 (has links)
In recent years, much research has focused on Algal High Rate Oxidation Ponds as both an economic means for wastewater treatment and as a system for the mass production of algae. With the advent of these systems for the treatment of saline organic effluents, the extreme halophile, Dunaliella salina was considered. In this study, the growth and productivity of a number of Dunaliella species (and strains thereof) was evaluated in hide soak liquor tannery effluent. Hide soak liquor, diluted to 20% with water, proved to be highly suitable as a growth medium for the majority of the Dunaliella species under study and in some instances, resulted in enhanced growth rates and higher biomass yields compared to those obtained in defined inorganic medium. A few Dunaliella species failed to grow in this effluent. A correlation was observed between the lack of growth displayed by these species in this organio-rich medium and their failure to utilise organic compounds. Glycine, a major component of this effluent, possibly stimulates the growth of Dunaliella. Studies on the mechanism of growth stimulation by glycine revealed that an algal-bacterial relationship existed whereby the bacteria mineralised the amino acid, releasing ammonia which was then utilised by the alga. Results of this work revealed significant variations in the intracellular glycerol content amongst the Dunaliella species under study. Large differences were also observed between the glycerol contents of effluent-grown and control Dunaliella cells, where the effluent-grown cells were characterised by greatly reduced intracellular glycerol content. These reduced glycerol levels are assumed to have arisen from the glycine-induced stimulation of glycerol release which was observed in this study, where the high glycine content of the hide soak liquor is proposed to have induced glycerol release. This enhanced glycerol release in tatmery effluent could play a central role in the fimction of Dunaliella-based High Rate Oxidation Ponding systems, by stimulating bacterial activity. Observed glycerol productivities were therefore proposed to be a fimction of the type and concentration of the organic constituents of the medium. A similar medium-induced phenomenon was observed in the starch content of Dunaliella cells.
32

Isovaline : a new analgesic

Wang, Tanche 05 1900 (has links)
There is a great need for new analgesics. The current problem in treatment of severe pain is that side effects limit the effectiveness of therapy. Glycine receptors are important in modulation of nociception, suggesting a novel class of analgesics. Previous studies in rats show that intrathecal administration of glycine agonists and amino acids structurally similar to glycine have antinociceptive effects. The effects of isovaline, a unique, non-proteogenic glycine-like aminoacid, have not been studied. Isovaline is absorbed from the gut and transported across the blood-brain-barrier. We examined the hypothesis that isovaline produces antinociception in mice. Administration of strychnine, an antagonist at glycine receptors, into the cisterna magna or lumbar intrathecal space resulted in allodynia, localized to the somatotopic distribution of the trigeminal and lumbar nerves. These findings provided a basis for models of lumbar and trigeminal neuralgia. Racemic isovaline blocked strychnine induced allodynia in both models without apparent side effects. We next investigated the antinociceptive effects of glycine-like amino acids in formalin foot assay, a conventional rodent model of acute and chronic pain. Antinociceptive effects were demonstrated on intrathecal administration of glycine, beta-alanine, and isovaline. Intravenous isovaline produced significant antinociceptive effects in the formalin foot model. The toxicity of isovaline and related amino acids were determined. Exploratory behavior, gait, and responses to stimuli were used to assess sedation. The rotarod test was used to examine central nervous system (CNS) and neuromuscular toxicities of intravenous isovaline. Lumbar administration of glycine and beta-alanine caused scratching and/or lower body weakness. Isovaline at 7-times intrathecal ED50 produced lower body weakness in some animals. None of the amino acids produced sedation comparable to morphine. At 6-times ED50, beta-alanine produced weakness. Both glycine (ED50) and beta-alanine (3x ED50) but not isovaline produced local nerve irritation. Intracisternal injection of glycine did not reverse allodynia and resulted in death. Neither R nor S enantiomers of isovaline impaired performance on the rotarod test. Isovaline has significant antinociceptive properties. Given the absence of apparent CNS or motor toxicity, isovaline has potential as a clinical analgesic. / Medicine, Faculty of / Anesthesiology, Pharmacology and Therapeutics, Department of / Graduate
33

Modulation de la neurogénèse par la glycine

Côté, Sébastien 11 1900 (has links)
Les vertébrés, du poisson à l'homme, possèdent un potentiel membranaire médié en partie par les ions chlorure (Cl-). L’une des premières formes d’activité neuronale lors du développement est la dépolarisation médiée par les ions chlorures extrudés par les canaux glycinergiques (GlyR) et GABAergiques. Cette dépolarisation est rendu possible grâce à l’expression retardée du co-transporteur d’ions chlorure et de potassium KCC2 lors du développement qui génère un gradient hyperpolarisant postnatalement chez les mammifères. Le rôle de cette dépolarisation précoce paradoxale durant le développement est inconnu. En injectant l’ARNm de KCC2 dans des embryons de poissons zébrés nouvellement fertilisé, nous avons devancé l’expression de ce co-transporteur rendant ainsi la glycine hyperpolarisante dans tous les neurones dès les premières phases du développement. Nous avons aussi ciblé le récepteur glycinergique directement en bloquant son activité et son expression à l’aide d’une drogue spécifique, la strychnine et d’un morpholino antisens (Knockdown). Dans les trois cas (KCC2, strychnine et GlyR KD), les perturbations de l’activité neuronale ont provoqués des erreurs dans la neurogenèse, en particulier une diminution du nombre d’interneurones sans avoir d’effets sur les motoneurones et les neurones sensoriels. De plus, en bloquant les canaux calciques activés à bas voltage dans le développement avec la drogue nifedipine, il y a des erreurs dans la neurogénèse semblables à celles remarquées dans les trois conditions précédentes. Nous concluons que la dépolarisation précoce par la glycine permet l’entrée du calcium et l’activation de la neurogénèse chez les interneurones. / Vertebrates, from fish to man, have a membrane potential mediated in part by chloride ions (Cl-). One of the first neuronal activity during development of the zebrafish spinal cord is cell depolarisation mediated by chloride extrusion via glycinergic receptors (GlyRs) and GABAergic receptors. This depolarisation is due to the absence of chloride-potassium cotransport channel KCC2, whose expression comes later in development, creating a hyperpolarising gradient. The role of this paradoxal depolarisation period during early stages of development is still unknown. By injecting KCC2 mRNA in newly fertilised zebrafish embryos, we expressed this co-transporter channel in neurons causing glycine to hyperpolarize in early phases of development. We also directly targeted the glycine receptor (GlyR) itself by blocking its activation with a chronic treatment of Strychnine, a specific drug, and by knocking down the expression of this receptor with an antisense morpholino injection. In those three conditions (KCC2, Strychnine and GlyR KD), perturbation of neuronal activity provoked major defects in neurogenesis, particulary in development of interneurons, without affecting other types of cells like motoneurons and sensory neurons. In addition, blocking low-voltage activated calcium channels with nifedipine provoked similar phenotypes. We conclude that the early glycine-mediated depolarisation allow calcium entry, thus activating certain aspects of interneurons neurogenesis.
34

Caracterização fisiológica e responsividade de grupos de maturação da cultura da soja submetida à aplicação de bioestimulante / Physiological characterization and reponsiveness of maturation groups of soybean crops submitted to the application of biostimulants

Soares, Jerssica Nogueira 28 August 2017 (has links)
A caracterização e o manejo fisiológico das culturas principalmente da soja, tem se tornado um potencial para que as culturas expressem o seu máximo. Dentre os principais quesitos a serem analisados são os grupos de maturação da cultura, pois cada cultivar tem uma região em que o seu genótipo está mais propicio a expressar o seu máximo potencial. Além de um bom posicionamento a agricultura vem utilizado substâncias para que melhorem ou potencializem as produtividades das culturas, substâncias elas que podem ser extratos de algas, micronutrientes, aminoácidos. Porém ainda são poucas as informações sobre os reais efeitos e formas de atuação dos mesmos e se o grupo de maturação de soja pode influenciar na atuação. Com isso o presente trabalho teve como objetivo caracterizar Grupos de maturação e responsividade da soja com a aplicação de bioestimulantes. Foram realizados dois experimentos no Campus II do Centro Universitário de Patos de Minas (UNIPAM). Em ambos os experimentos foram realizadas as avaliações teor de proteína total solúvel; Índice SPAD; teor de prolina, enzimas antioxidantes (SOD, POD e H2O2); fitomassa seca de raiz, caule, folha, total; número e fitomassa seca de vagens; número de nós e ramificações; massa de 1000 grãos e produtividade. No Experimento I utilizou três cultivares NS 7709 IPRO (7.2); NS 6909 IPRO (6.9) e AS 3610 IPRO (6.1), conferindo em três tratamentos com 8 repetições em delineamento inteiramente casualizado. No Experimento II foram utilizados dois cultivares NS 7709 IPRO (7.2); NS 6909 IPRO (6.9), com três tratamentos com aplicações via sementes e foliar [Padrão- CoMo Platinum® (Tratamento de sementes); CoMo Platinum® + Foth TB® (Tratamento de sementes e foliar) e Masteraiz Leg® + Master Equaliza® + Forth TB® (Tratamento de sementes e foliar)], com delineamento em sistema bifatorial 3x2 em blocos casualizados. Com os resultados encontrados no trabalho pode-se concluir que: que cultivares de menor Grupo de maturação com o melhoramento genético estão sendo mais produtivos do que os de maiores Grupos de maturação; plantas com maior Grupo de maturação apresenta menores níveis de estresses; no desenvolvimento inicial cultivares de menores GM (NS 6909 IPRO-6.9 e AS 3610 IPRO-6.1) apresentam melhores crescimentos de raiz e caule; no estádio reprodutivo cultivar de menor GM (AS 3610 IPRO-6.1) apresentou melhor crescimento de caule, folha e total, número de nós, ramificações e vagens, fitomassa seca de vagens e maior produtividade; a maior duração do ciclo fenológico não acarretou em incremento de produtividade nos cultivares NS 7709 IPRO (7.2) e NS 6909 IPRO (6.9); com a aplicação de bioestimulantes (CoMo Platinum®, CoMo Platinum® + Forth TB®,Masteraiz Leg® + Master Equaliza® + Forth TB®) o cultivar de maior Grupo de maturação se apresentou mais responsivo, por meio de maiores fitomassa seca de raiz, caule, folha e total, maior número de ramificações e massa de 1000 grãos; com relação a produtividade os dois cultivares utilizados responderam de formam igual a aplicação de CoMo Platinum®, CoMo Platinum® + Forth TB®, Masteraiz Leg® + Master Equaliza® + Forth TB®; o tratamento de sementes com Masteraiz Leg® e aplicação foliar de Master Equaliza® + Forth TB®, proporcionou aumento médio de fitomassa seca de raiz, caule, folha e total, maior número de vagens, ramificações, massa de 1000 grãos e produtividade. / Physiological characterization and responsiveness of maturation groups of soybean crops submitted to the application of biostimulants. The characterization and physiological management of crops, mainly of soybean, has become a potential measure for them to express their maximum yield. Among the main questions to be analyzed are the maturation groups of the crop, since each cultivar has a region in which a genotype is more propitious to express its maximum potential. In addition to a good positioning, agriculture uses substances that improve or potentiate the productivities of crops, substances that can be extracts of algae, micronutrients, amino acids. However, there is still little information on the actual effects and forms of their action and whether the soybean maturation group can influence the performance. Thus, the present work had as objective to characterize groups of maturation and responsiveness of soybean with the application of biostimulants. Two experiments were carried out in the Campus II of the University Center of Patos de Minas (UNIPAM). In both experiments evaluations were made of: total soluble protein content; SPAD Index; Proline content, antioxidant enzymes (SOD, POD and H2O2); Root dry matter, stem, leaf, total; Number and dry matter of pods; Number of nodes and branches; Mass of 1000 grains and productivity. In Experiment I, three cultivars NS 7709 IPRO (7.2) were used; NS 6909 IPRO (6.9) and AS 3610 IPRO (6.1), in three treatments with 8 replicates in a completely randomized design. In Experiment II, two cultivars NS 7709 IPRO (7.2) were used; NS 6909 IPRO (6.9), with three treatments with seeds and foliar applications [Standard - CoMo Platinum® (Seed Treatment); CoMo Platinum® + Foth TB® (Seed and Leaf Treatment) and Masteraiz Leg® + Master Equaliza® + Forth TB® (Seed and Leaf Treatment), with a 3x2 two-factor randomized block design. With the results we can conclude that: cultivars of the lower maturation group with genetic improvement were more productive than those of the larger maturation groups; plants of the higher maturation group presented lower levels of stress; (NS 6909 IPRO-6.9 and AS 3610 IPRO-6.1) showed better root and stem growths in the initial development stage; AS 3610 IPRO (6.1) presented better stem, leaf and total growth, number of nodes, branches and pods, dry pod phytomass and higher productivity; the longer duration of the phenological cycle did not lead to na increase in productivity of the cultivars NS 7709 IPRO (7.2) and NS 6909 IPRO (6.9); with the application of biostimulants (CoMo Platinum®, CoMo Platinum® + Forth TB®, Masteraiz Leg® + Master Equaliza® + Forth TB®), the cultivar of the larger maturation group was more responsive due to larger dry root, stem, leaf and total phytomasses, greater number of branches and mass of 1000 grains; with respect to productivity the two cultivars responded equally to the application of CoMo Platinum®, CoMo Platinum® + Forth TB®, Masteraiz Leg® + Master Equaliza® + Forth TB®; the seed treatment with Masteraiz Leg® and foliar application of Master Equaliza® + Forth TB® provide a mean increase of root, stem, leaf and total dry matters, greater number of pods, branches, mass of 1000 grains and productivity.
35

Modulation de la neurogénèse par la glycine

Côté, Sébastien 11 1900 (has links)
Les vertébrés, du poisson à l'homme, possèdent un potentiel membranaire médié en partie par les ions chlorure (Cl-). L’une des premières formes d’activité neuronale lors du développement est la dépolarisation médiée par les ions chlorures extrudés par les canaux glycinergiques (GlyR) et GABAergiques. Cette dépolarisation est rendu possible grâce à l’expression retardée du co-transporteur d’ions chlorure et de potassium KCC2 lors du développement qui génère un gradient hyperpolarisant postnatalement chez les mammifères. Le rôle de cette dépolarisation précoce paradoxale durant le développement est inconnu. En injectant l’ARNm de KCC2 dans des embryons de poissons zébrés nouvellement fertilisé, nous avons devancé l’expression de ce co-transporteur rendant ainsi la glycine hyperpolarisante dans tous les neurones dès les premières phases du développement. Nous avons aussi ciblé le récepteur glycinergique directement en bloquant son activité et son expression à l’aide d’une drogue spécifique, la strychnine et d’un morpholino antisens (Knockdown). Dans les trois cas (KCC2, strychnine et GlyR KD), les perturbations de l’activité neuronale ont provoqués des erreurs dans la neurogenèse, en particulier une diminution du nombre d’interneurones sans avoir d’effets sur les motoneurones et les neurones sensoriels. De plus, en bloquant les canaux calciques activés à bas voltage dans le développement avec la drogue nifedipine, il y a des erreurs dans la neurogénèse semblables à celles remarquées dans les trois conditions précédentes. Nous concluons que la dépolarisation précoce par la glycine permet l’entrée du calcium et l’activation de la neurogénèse chez les interneurones. / Vertebrates, from fish to man, have a membrane potential mediated in part by chloride ions (Cl-). One of the first neuronal activity during development of the zebrafish spinal cord is cell depolarisation mediated by chloride extrusion via glycinergic receptors (GlyRs) and GABAergic receptors. This depolarisation is due to the absence of chloride-potassium cotransport channel KCC2, whose expression comes later in development, creating a hyperpolarising gradient. The role of this paradoxal depolarisation period during early stages of development is still unknown. By injecting KCC2 mRNA in newly fertilised zebrafish embryos, we expressed this co-transporter channel in neurons causing glycine to hyperpolarize in early phases of development. We also directly targeted the glycine receptor (GlyR) itself by blocking its activation with a chronic treatment of Strychnine, a specific drug, and by knocking down the expression of this receptor with an antisense morpholino injection. In those three conditions (KCC2, Strychnine and GlyR KD), perturbation of neuronal activity provoked major defects in neurogenesis, particulary in development of interneurons, without affecting other types of cells like motoneurons and sensory neurons. In addition, blocking low-voltage activated calcium channels with nifedipine provoked similar phenotypes. We conclude that the early glycine-mediated depolarisation allow calcium entry, thus activating certain aspects of interneurons neurogenesis.
36

SOYBEAN QTL FOR YIELD AND YIELD COMPONENTS ASSOCIATED WITH GLYCINE SOJA ALLELES

Li, Dandan 01 January 2006 (has links)
USA soybean germplasm has a narrow genetic base that could be augmented by alleles from the wild species Glycine soja which positively influence agronomic traits. The objective of this study was to identify such alleles for yield and yield component QTL (quantitative trait loci). Two populations of 150 BC2F4 lines were generated from a mating between recurrent parent Glycine max 7499 and donor parent Glycine soja PI 245331 with one line in each population tracing back to the same BC2 plant. Population A was used for the QTL identification analysis and population B was used for the QTL verification test. The population A lines were genotyped at 120 SSR marker loci and one phenotype marker, covering a total map length of 1506 cM in 20 linkage groups with an average interval size of 12.5 cM. There were nine putative QTL significantly (Pandlt;0.0001, LODandgt;3.0) associated with yield and yield component traits across 3 environments. One QTL for seed yield was identified using the combined data; the G. soja allele at satt511 on LG-A1 was associated with increased seed yield (LOD=4.3) with an additive yield effect of 190 235 kg ha-1 depending on the QTL analysis method. The phenotypic variance accounted for by the QTL at satt511 was 12%. This QTL also provided a significant yield increase across environments in the validation population; lines that were homozygous for the G. soja allele at satt511 demonstrated a 6.3% (P=0.037) yield increase over lines that were homozygous for the G. max allele. One seed filling period QTL was identified at satt335 (LOD=4.0) on LG-F with an additive effect of +1 day. This QTL also provided a +1 day additive effect (LOD=3.3) on maturity. These results demonstrate the potential of using exotic germplasm to improve soybean yield.
37

Postnatal development of glycinergic synaptic transmission and biophysical properties of glycine receptor-channels /

Singer, Joshua H. January 1998 (has links)
Thesis (Ph. D.)--University of Washington, 1998. / Vita. Includes bibliographical references (leaves [73]-89).
38

Soyatoxina-2 - uma nova toxina de sementes de soja: aspectos estruturais, do mecanismo de aÃÃo e efeitos biolÃgicos / Soyatoxina-2 - a new toxin of soy seeds: structural aspects, of the mechanism of action and biological effect

Daniele de Oliveira Bezerra de Sousa 28 April 2006 (has links)
FundaÃÃo Cearense de Apoio ao Desenvolvimento Cientifico e TecnolÃgico / nÃo hà / Soyatoxina 2 (SYTX-2) à uma proteÃna tÃxica isolada de sementes de soja [Glycine max (L.) Merril], genÃtipo BR-10, sendo letal para camundongos quando administrada por via intraperitoneal (DL50 4,5  0,1 mg/Kg de peso corpÃreo). Os sintomas observados apÃs sua administraÃÃo foram piloereÃÃo, taquicardia, estiramento de patas e da cauda, diurese e convulsÃes tÃnico-clÃnicas, que precederam a morte do animal. A SYTX-2 foi purificada do extrato bruto de soja por fracionamento com sulfato de amÃnio, cromatografias de troca iÃnica (DEAE-celulose), de afinidade (Sepharose-4B-tripsina) e de filtraÃÃo em gel (Superdex 200HR 10/30). A inclusÃo de ditiotreitol 0,005 M no tampÃo de extraÃÃo e em outros tampÃes utilizados durante o processo de purificaÃÃo foi crucial para obtenÃÃo da SYTX-2 num estado altamente homogÃneo e preservaÃÃo da toxicidade. A SYTX-2 nÃo à uma glicoproteÃna e apresenta massa molecular aparente de 28,0 e 25,4 kDa, quando avaliada por PAGE-SDS e filtraÃÃo em gel em coluna de Superdex 200HR 10/30, respectivamente, e coeficiente de extinÃÃo molar (ε1%1cm) de 16,9. Sua seqÃÃncia NH2-terminal exibiu uma identidade de 75%, quando relacionada com aquela de uma endoquitinase acÃdica da classe III de sementes de soja. Ao lado de sua atividade tÃxica, a SYTX-2 apresentou atividade quitinÃsica de 1,34 nKat/mgP. Essa toxina, quando em contato com o nervo ciÃtico de ratos foi capaz de aumentar a amplitude pico-a-pico, comprovando sua aÃÃo neurotÃxica. A SYTX-2 tambÃm mostrou atividade prÃ-inflamatÃria, induzindo migraÃÃo de neutrÃfilos para a cavidade peritoneal de ratos, cujo pico se deu 8 h apÃs sua administraÃÃo. AvaliaÃÃo de seu papel fisiolÃgico, mostrou que a SYTX-2 exerceu efeitos negativos sobre o desenvolvimento do inseto-peste de feijÃo-de-corda Callosobruchus maculatus, particularmente na emergÃncia do adulto e no tempo mÃdio de desenvolvimento larval. Adicionalmente, SYTX-2 foi tÃxica para ninfas de Dysdercus peruvianus, causando reduÃÃo no ganho de peso corpÃreo e na taxa de sobrevivÃncia. A SYTX-2 tambÃm atuou negativamente sobre o nematÃide Meloidogyne incognita, impedindo sua mobilidade. Por outro lado, a SYTX-2 nÃo foi capaz de inibir a germinaÃÃo de esporos e nem o desenvolvimento de hifas dos fungos Colletotrichum lindemuthianum, C. gloesporioides, Rhizoctonia solani, Cercospora kikuchii, Fusarium solani, F. oxysporum e Aspergillus niger, nas condiÃÃes de ensaio realizadas no presente trabalho. Em resumo, este trabalho apresenta, pela primeira vez, dados de uma proteÃna neurotÃxica contendo uma atividade quitinÃsica nÃo usual, cujo papel parece estar relacionado aos mecanismos de defesa da planta. Nesse contexto, SYTX-2 possui potencial para aplicaÃÃo biotecnolÃgica como um novo agente de defesa vegetal contra insetos-peste e nematÃide-parasitas / Soyatoxin 2 (SYTX-2) is a toxic protein isolated from soybean seeds [Glycine max (L.) Merril], genotype BR-10, lethal to mice upon intraperitoneal injection (LD50 4.5  0.1 mg/Kg body weight). The symptoms observed upon administration were pilloerection, tachycardia, paw and tail extending, diuresis and tonic-clonic convulsions prior to death. The SYTX-2 was purified from soybean crude extract by ammonium sulfate fractionation, ion-exchange (DEAE-cellulose), affinity (Sepharose-4B-trypsin) and gel filtration (Superdex 200HR 10/30) chromatography. Inclusion of 0.005 M dithiothreitol in the extracting and other buffers used during the purification process was crucial to obtain highly homogenous SYTX-2 and to preserve the toxicity. SYTX-2 is not a glycoprotein and has apparent molecular masses of 28.0 and 25.4 kDa as measured by SDS-PAGE and gel filtration in Superdex 200HR 10/30 column, respectively, and a molar extinction coefficient (ε1% 1cm) of 16.9. Its NH2-terminal sequence shows 75% identity with a class III acidic endochitinase from soybean seeds. Therefore, besides to its toxic properties, SYTX-2 presented chitinase activity of 1.34 nKat/mgP. This toxin, when in contact with the sciatic nerve of rats was able to increase the peak-to-peak amplitude, confirming its neurotoxic action. Moreover, SYTX-2 presented pro-inflammatory activity, inducing neutrophil migration into the peritoneal cavity of rats which peaked at 8 h after administration. Evaluation of its physiological role showed that SYTX-2 exerted negative effect on the development of the cowpea pest insect Callosobruchus maculates, particularly on adult emergence and in the mean larval development time. Additionally, SYTX-2 was toxic to Dysdercus peruvianus nymphs, as it caused reduction of both the body weight gain and survival rate. SYTX-2 also acted negatively on the root-knot nematode Meloidogyne incognita by hindering its mobility. On the other hand, SYTX-2 did not inhibit neither the spore germination nor the hyphal development of the phytopathogenic fungi Colletotrichum lindemuthianum, C. gloesporioides, Rhizoctonia solani, Cercospora kikuchii, Fusarium solani, F. oxysporum and Aspergillus niger, under the assay conditions carried out in this present work. In summary this study presents, for the first time, data on a neurotoxin protein with additional unusual chitinase activity, whose physiological role is likely related to the plant defense mechanisms. Accordingly, SYTX-2 possesses potential biotechnological application as a novel plant defensive agent against insect pests and parasitic nematodes.
39

Caracterização fisiológica e responsividade de grupos de maturação da cultura da soja submetida à aplicação de bioestimulante / Physiological characterization and reponsiveness of maturation groups of soybean crops submitted to the application of biostimulants

Jerssica Nogueira Soares 28 August 2017 (has links)
A caracterização e o manejo fisiológico das culturas principalmente da soja, tem se tornado um potencial para que as culturas expressem o seu máximo. Dentre os principais quesitos a serem analisados são os grupos de maturação da cultura, pois cada cultivar tem uma região em que o seu genótipo está mais propicio a expressar o seu máximo potencial. Além de um bom posicionamento a agricultura vem utilizado substâncias para que melhorem ou potencializem as produtividades das culturas, substâncias elas que podem ser extratos de algas, micronutrientes, aminoácidos. Porém ainda são poucas as informações sobre os reais efeitos e formas de atuação dos mesmos e se o grupo de maturação de soja pode influenciar na atuação. Com isso o presente trabalho teve como objetivo caracterizar Grupos de maturação e responsividade da soja com a aplicação de bioestimulantes. Foram realizados dois experimentos no Campus II do Centro Universitário de Patos de Minas (UNIPAM). Em ambos os experimentos foram realizadas as avaliações teor de proteína total solúvel; Índice SPAD; teor de prolina, enzimas antioxidantes (SOD, POD e H2O2); fitomassa seca de raiz, caule, folha, total; número e fitomassa seca de vagens; número de nós e ramificações; massa de 1000 grãos e produtividade. No Experimento I utilizou três cultivares NS 7709 IPRO (7.2); NS 6909 IPRO (6.9) e AS 3610 IPRO (6.1), conferindo em três tratamentos com 8 repetições em delineamento inteiramente casualizado. No Experimento II foram utilizados dois cultivares NS 7709 IPRO (7.2); NS 6909 IPRO (6.9), com três tratamentos com aplicações via sementes e foliar [Padrão- CoMo Platinum® (Tratamento de sementes); CoMo Platinum® + Foth TB® (Tratamento de sementes e foliar) e Masteraiz Leg® + Master Equaliza® + Forth TB® (Tratamento de sementes e foliar)], com delineamento em sistema bifatorial 3x2 em blocos casualizados. Com os resultados encontrados no trabalho pode-se concluir que: que cultivares de menor Grupo de maturação com o melhoramento genético estão sendo mais produtivos do que os de maiores Grupos de maturação; plantas com maior Grupo de maturação apresenta menores níveis de estresses; no desenvolvimento inicial cultivares de menores GM (NS 6909 IPRO-6.9 e AS 3610 IPRO-6.1) apresentam melhores crescimentos de raiz e caule; no estádio reprodutivo cultivar de menor GM (AS 3610 IPRO-6.1) apresentou melhor crescimento de caule, folha e total, número de nós, ramificações e vagens, fitomassa seca de vagens e maior produtividade; a maior duração do ciclo fenológico não acarretou em incremento de produtividade nos cultivares NS 7709 IPRO (7.2) e NS 6909 IPRO (6.9); com a aplicação de bioestimulantes (CoMo Platinum®, CoMo Platinum® + Forth TB®,Masteraiz Leg® + Master Equaliza® + Forth TB®) o cultivar de maior Grupo de maturação se apresentou mais responsivo, por meio de maiores fitomassa seca de raiz, caule, folha e total, maior número de ramificações e massa de 1000 grãos; com relação a produtividade os dois cultivares utilizados responderam de formam igual a aplicação de CoMo Platinum®, CoMo Platinum® + Forth TB®, Masteraiz Leg® + Master Equaliza® + Forth TB®; o tratamento de sementes com Masteraiz Leg® e aplicação foliar de Master Equaliza® + Forth TB®, proporcionou aumento médio de fitomassa seca de raiz, caule, folha e total, maior número de vagens, ramificações, massa de 1000 grãos e produtividade. / Physiological characterization and responsiveness of maturation groups of soybean crops submitted to the application of biostimulants. The characterization and physiological management of crops, mainly of soybean, has become a potential measure for them to express their maximum yield. Among the main questions to be analyzed are the maturation groups of the crop, since each cultivar has a region in which a genotype is more propitious to express its maximum potential. In addition to a good positioning, agriculture uses substances that improve or potentiate the productivities of crops, substances that can be extracts of algae, micronutrients, amino acids. However, there is still little information on the actual effects and forms of their action and whether the soybean maturation group can influence the performance. Thus, the present work had as objective to characterize groups of maturation and responsiveness of soybean with the application of biostimulants. Two experiments were carried out in the Campus II of the University Center of Patos de Minas (UNIPAM). In both experiments evaluations were made of: total soluble protein content; SPAD Index; Proline content, antioxidant enzymes (SOD, POD and H2O2); Root dry matter, stem, leaf, total; Number and dry matter of pods; Number of nodes and branches; Mass of 1000 grains and productivity. In Experiment I, three cultivars NS 7709 IPRO (7.2) were used; NS 6909 IPRO (6.9) and AS 3610 IPRO (6.1), in three treatments with 8 replicates in a completely randomized design. In Experiment II, two cultivars NS 7709 IPRO (7.2) were used; NS 6909 IPRO (6.9), with three treatments with seeds and foliar applications [Standard - CoMo Platinum® (Seed Treatment); CoMo Platinum® + Foth TB® (Seed and Leaf Treatment) and Masteraiz Leg® + Master Equaliza® + Forth TB® (Seed and Leaf Treatment), with a 3x2 two-factor randomized block design. With the results we can conclude that: cultivars of the lower maturation group with genetic improvement were more productive than those of the larger maturation groups; plants of the higher maturation group presented lower levels of stress; (NS 6909 IPRO-6.9 and AS 3610 IPRO-6.1) showed better root and stem growths in the initial development stage; AS 3610 IPRO (6.1) presented better stem, leaf and total growth, number of nodes, branches and pods, dry pod phytomass and higher productivity; the longer duration of the phenological cycle did not lead to na increase in productivity of the cultivars NS 7709 IPRO (7.2) and NS 6909 IPRO (6.9); with the application of biostimulants (CoMo Platinum®, CoMo Platinum® + Forth TB®, Masteraiz Leg® + Master Equaliza® + Forth TB®), the cultivar of the larger maturation group was more responsive due to larger dry root, stem, leaf and total phytomasses, greater number of branches and mass of 1000 grains; with respect to productivity the two cultivars responded equally to the application of CoMo Platinum®, CoMo Platinum® + Forth TB®, Masteraiz Leg® + Master Equaliza® + Forth TB®; the seed treatment with Masteraiz Leg® and foliar application of Master Equaliza® + Forth TB® provide a mean increase of root, stem, leaf and total dry matters, greater number of pods, branches, mass of 1000 grains and productivity.
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Inheritance of the Gene(s) Controlling Leaflet Shape in Soybean

Porter, Caroline Yancey 11 April 2001 (has links)
Many soybean [Glycine max (L.) Merrill] cultivars have narrow leaflet shape but it is not known if all of these lines derive this trait from the ln gene or another locus. This project was conducted to determine the inheritance of the narrow leaflet trait in several soybean genotypes and wild [Glycine soja Sieb. et Zucc.] accessions, and also to determine the allelism of the genes for this trait in the selected lines. The parents, F1, F2 and F2:3 generations were grown at Kentland Research Farm near Blacksburg, VA or in the greenhouse. The F2 and F2:3 generations (where available) were observed for segregation in leaflet shape. The populations were scored as having either broad or narrow leaflets using visual classification and leaf measurements when necessary. 'Camp' was crossed with broad leaflet parent 'Essex' to study the inheritance of the narrow leaflet trait in Camp. Observation of the F2 and F2:3 generations lead to the conclusion that a single recessive gene controls leaflet shape in Camp. Narrow leaf parents 'SRF 400' and Camp were crossed with lines having the ln gene (T41, S56, and D64-4731). None of the crosses among Camp, T41, SRF 400, S56 and D64-4731 segregated for leaflet shape in the F2 generation leading to the conclusion that they all have the ln allele at the same locus controlling lanceolate leaflet shape. T313, a line containing a gene for narrow rugose leaflets (lnr), was crossed with Camp to study allelism between the lnr and ln genes. Segregation for leaflet shape was observed in the F2 and F2:3 generations allowing the conclusion that the lnr gene controlling the narrow rugose leaflet trait in T313 is at a locus independent from the ln gene. A deficiency of narrow rugose plants was observed in all of the populations with T313 as a parent, and was theorized as being caused by selection against lnr gametes. After adjustment for the lnr deficiency, the F2 data appeared to fit a 9 broad : 3 narrow : 4 narrow rugose ratio. Three G. soja lines were crossed to broad and narrow leaflet parents and the F2 generations were examined to determine the inheritance of the very narrow leaf phenotype. The results indicate that there are one or two recessive genes controlling narrow leaflet shape in the G. soja accessions, which are not allelic to the ln gene. Since these populations were not advanced to the F3 generation, definite conclusions cannot be drawn about the genetics of the very narrow leaf phenotype. / Master of Science

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