Les plantes de la famille des légumineuses ont la particularité d’héberger intracellulairement des bactéries du sol communément appelées rhizobia. Cette interaction symbiotique se déroule au sein de la nodosité, un organe formé de-novo au niveau racinaire. L’activité nitrogénase bactérienne y permet la réduction de l’azote atmosphérique en NH3 assimilable par la plante. Si les mécanismes moléculaires gouvernant la reconnaissance entre les deux partenaires, l’infection intracellulaire et l’organogénèse des nodosités ont été particulièrement bien décrits au cours des dernières décennies ; peu d’informations sont quant à elles disponibles sur l’origine de ce programme morphogénétique nouveau chez les Angiospermes. Les nodosités des deux légumineuses modèles Medicago truncatula et Pisum sativum sont qualifiées d’indéterminées en raison de la persistance d’un méristème en position apicale. Les nodosités des mutants noot (nodule-root) chez M. truncatula et coch (cochleata) chez le pois développent des racines ectopiques à partir des tissus vasculaires des nodosités, montrant ainsi que les nodosités et racines sont plus apparentées que leur simple comparaison anatomique ne pouvait le suggérer. En outre, l‘activité mérsitématique des nodosités est fortement perturbée chez ces deux mutants qui présentent des nodosités multilobées et élargies. Nous avons montré que les gènes MtNOOT et PsCOCHLEATA étaient orthologues aux gènes AtBLADE-ON-PETIOLE1 et 2 qui codent deux activateurs transcriptionels redondants et cruciaux pour la régulation de nombreux processus développementaux chez Arabidopsis thaliana. En raison de la forte conservation des fonctions biologiques des protéines NOOT, BOPs et COCH, notamment pour la régulation de la morphologie foliaire et florale, de l’architecture de l’inflorescence et de la formation des zones d’abscission, nous proposons que ces fonctions représentent les fonctions ancestrales de la famille des gènes NBCL (NOOT BOP COCH LIKE). L’étude de déterminants hormonaux et génétiques du méristème racinaire dans les nodosités sauvages et mutantes noot ainsi que la caractérisation de l’homéose nodule/racine nous ont permis de dégager des parallèles importants entre les tissus périphériques de la nodosité et ceux de la racine. Nous proposons donc un modèle de développement des tissus vasculaires de la nodosité par co-option du programme racinaire dont la répression est en partie assurée par NOOT. / Legume plants are able to house intracellularly soil bacteria collectively called rhizobia. This symbiotic process takes place in a new organ generally formed on the host roots, the nodule. This interaction allows atmospheric nitrogen fixation to the benefit of the plant by using the bacterial nitrogenase activity. Despite an exhaustive description of molecular determinants of this interaction allowing partners recognition, intracellular accommodation and early nodule organogenesis, less is known about cell lineage and identity of the nodule morphogenetic pathway which is thought to represent a recent acquisition during Angiosperms evolution. Nodules from model legumes such as Medicago truncatula or Pisum sativum are described as indeterminate because of the persistence of a distal meristem. The noot (nodule-root) and coch (coch) mutants, in M. truncatula and P. sativum respectively, develop ectopic roots from the nodule vasculature, suggesting that roots and symbiotic nodules are more closely related than previously admitted based on their anatomical comparison. Moreover, the meristematic activity is strongly modified in noot and coch nodules that harbor numerous and enlarged lobes. We showed that NOOT and COCH are orthologs to AtBLADE-ON-PETIOLE1 and 2 redundant transcriptional activators that represent key regulators of versatile plant developmental processes in Arabidopsis thaliana. Because of the conservation of biological functions controlled by NOOT, BOPs and COCH proteins, in particular the regulation of leaf and floral morphologies, abscission zones formation and inflorescence architecture, we proposed that such functions are inherited from a NBCLs (NOOT BOP COCH LIKE) ancestral gene. Our studies of hormonal and genetic determinants of the root meristem in noot and wild-type nodules as well as the characterization of nodule-to-root homeosis have highlighted important parallels between nodule peripheral tissues and roots. We thus propose a model of nodule vascular unit maintenance by the NOOT-dependent repression of a co-opted root morphogenetic program.

The pea weevil (Bruchus pisorum L.) is the most significant pest of field pea (Pisum sativum L.) in Australia. The only available means for controlling pea weevil at the present time is with chemical pesticides. The aim of this study was to introgress natural pea weevil resistance, derived from the wild pea species, Pisum fulvum Sibth. & Sm. into cultivated field pea and devise strategies for screening for the resistance with breeding applications. Traditional breeding methods were used to transfer pea weevil resistance from P. fulvum accession ‘ATC113’ to cultivated field pea, cv. ‘Pennant’. Progeny derived from this population were examined for inheritance of pod and seed resistance. Seed resistance in F2 plants segregated in a ratio of 1:37:26 (resistant: mixed response: susceptible), indicating a trigenic mode of inheritance (1:63), with at least three major recessive genes controlling pea weevil resistance. Seed resistance was conserved over consecutive generations (F2 to F5) and was successfully transferred to populations crossed with a second adapted field pea variety‘Helena’. Pod resistance presented as a quantitative trait in the F2 population, but this resistance was not retained in subsequent generations. Amplified fragment length polymorphisms (AFLPs) were sought in the parents and in resistant and susceptible F3 plants. Restricted maximum likelihood (REML) analysis was used to identify 13 AFLP markers with a statistically significant association with pea weevil resistance and 23 with pea weevil susceptibility. Principal coordinate analysis (PCO) showed that the AFLP marker loci formed clusters in the PCO space, which could indicate the three proposed gene locations. Eight AFLP markers were cloned, sequenced and converted to sequence characterised amplified regions (SCAR). Two SCAR markers, SC47359 and SC47435 were polymorphic between the resistant and susceptible parents. Both markers co-segregated with the resistant lines and with 30-36% of susceptible lines. Plants which did not possess either band were highly susceptible. The other PCR products were either monomorphic between the resistant and susceptible parents or produced more than one band product. A range of phenotypic traits was measured in the F2 population derived from the hybridisation between P. fulvum and P. sativum and associations with pea weevil resistance were made. In the F2 population, pea weevil resistance was not correlated with any of the negative traits originating from the wild parent, such as increased basal branching, dark seed coat or small seed size, neither was resistance correlated with flower colour, flowering time or seeds per pod. Pea weevil resistance should therefore be transferable with minimal linkage drag. A convenient morphological marker, such as flower or seed colour was not identified in this study based on these results. Using principal component analysis (PCA) as a visual tool, resistant and semi-resistant plants in the F3 and ‘backcross’ introgression populations were identified with improved trait performance compared with the wild parent

The aim of this diploma thesis was to evaluate selected parameters indicating the quality of dried pea seeds (Pisum sativum L.) in selected group of two varieties. Literary research focuses mainly on pea production in the Czech Republic and worldwide, for breeding varieties, peas and seed recognition. The literary research directly follows the practical part, which deals with the process of recognition and certification of seeds of two varieties in practice. In addition, laboratory tests of pea seed quality, especially germination. This was set as part of the sub-supply, supply and cleanse seeds, for the Gambit variety it recorded 69% and fell to 37% for the Salamanca variety, which differed considerably from the pre-supply and delivery seeds. This research shows an internal view within the farm and the great complexity and difficulty of the seed certification process.

Made available in DSpace on 2016-02-26T12:59:36Z (GMT). No. of bitstreams: 1 LuciaMayumiHirata.pdf: 1395591 bytes, checksum: e27a98e6d36e8842db05c8c307aaf28b (MD5) Previous issue date: 2006-02-27 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / Pea (Pisum sativum L.) which has a wide variety of uses, due to the high nutritional value, can be used for animal feeding as well as food source for humans. Ascochyta blight disease is one of the most devastating diseases of this leguminous crop and is favored by cool climate associated with high relative humidity. The pathogen can be transmitted by infected seeds. With the increasing demand for healthier products without the use of chemical, the organic system of production is in expansion. The effectiveness of seed treatments, accepted by organic regulations, against A. pisi was evaluated. The treatments consisted of commercial biofungicides, experimental formulations based on microorganisms cultivated in laboratory and vegetal extracts, resistance inducers, physical methods based in the thermotherapy (aerated steam and hot water), and low energy electrons and the association of the physical methods and biological agents had in five experiments. Pea seeds, naturally infected with A. pisi were sown in sterilized commercial organic substrate and maintained under greenhouse conditions. Plant emergence and infection index were evaluated two weeks after sowing. Extract of Thymus vulgaris, Clonostachys rosea IK 726, the commercial product Micosat (Glomus sp. + Pseudomonas fluorescens + P. borealis + Bacillus subtilis), and the association of physical method with low energy electrons 140 and 130 kV with biological agent Bacillus subtilis (Serenade) were as effective in suppressing A. pisi as the standard chemicals used as controls / A ervilha apresenta alto valor nutritivo, e pode ser utilizada na alimentação humana e também na alimentação animal. Uma das doenças mais importante que ocorre na cultura da ervilha é causada pelo patógeno Ascochyta pisi, que é favorecida por temperaturas amenas e umidade elevada, e, podendo ser transmitida por sementes infectadas. Com a crescente procura por produtos mais saudáveis e sem o uso de defensivos químicos, o sistema de produção orgânico apresenta-se em expansão. O trabalho avaliou a eficácia dos tratamentos de sementes de ervilha no controle de A. pisi de acordo com o sistema orgânico. Foram testados biofungicidas comerciais, microrganismos cultivados em laboratório e extratos vegetais, indutores de resistência, métodos físicos baseados na termoterapia (vapor aerado e água aquecida), e elétrons de baixa energia e a associação dos tratamentos físicos e controle biológico, num total de cinco experimentos. Utilizaram-se sementes de ervilha naturalmente infectadas por Ascochyta pisi, semeadas em substrato orgânico comercial esterilizado e mantidas em casa-de-vegetação. Avaliaram-se emergência e índice de infecção duas semanas após a semeadura. O índice de infecção das plantas foi calculado em diferentes classes de infecção de acordo com Townsend-Heuberger, (1943). Extrato vegetal de Thymus vulgaris, Clonostachys rosea IK 726 e Micosat (Glomus sp. + Pseudomonas fluorescens + P. borealis + Bacillus subtilis), e a associação de tratamento físico com elétrons de baixa energia a 130 e 140 kV com o agente biológico Bacillus subtilis (Serenade) proporcionaram níveis de controle equivalentes ao tratamento químico

Made available in DSpace on 2016-02-26T12:59:13Z (GMT). No. of bitstreams: 1 LuciaMayumiHirata.pdf: 1395591 bytes, checksum: e27a98e6d36e8842db05c8c307aaf28b (MD5) Previous issue date: 2006-02-27 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / Pea (Pisum sativum L.) which has a wide variety of uses, due to the high nutritional value, can be used for animal feeding as well as food source for humans. Ascochyta blight disease is one of the most devastating diseases of this leguminous crop and is favored by cool climate associated with high relative humidity. The pathogen can be transmitted by infected seeds. With the increasing demand for healthier products without the use of chemical, the organic system of production is in expansion. The effectiveness of seed treatments, accepted by organic regulations, against A. pisi was evaluated. The treatments consisted of commercial biofungicides, experimental formulations based on microorganisms cultivated in laboratory and vegetal extracts, resistance inducers, physical methods based in the thermotherapy (aerated steam and hot water), and low energy electrons and the association of the physical methods and biological agents had in five experiments. Pea seeds, naturally infected with A. pisi were sown in sterilized commercial organic substrate and maintained under greenhouse conditions. Plant emergence and infection index were evaluated two weeks after sowing. Extract of Thymus vulgaris, Clonostachys rosea IK 726, the commercial product Micosat (Glomus sp. + Pseudomonas fluorescens + P. borealis + Bacillus subtilis), and the association of physical method with low energy electrons 140 and 130 kV with biological agent Bacillus subtilis (Serenade) were as effective in suppressing A. pisi as the standard chemicals used as controls / A ervilha apresenta alto valor nutritivo, e pode ser utilizada na alimentação humana e também na alimentação animal. Uma das doenças mais importante que ocorre na cultura da ervilha é causada pelo patógeno Ascochyta pisi, que é favorecida por temperaturas amenas e umidade elevada, e, podendo ser transmitida por sementes infectadas. Com a crescente procura por produtos mais saudáveis e sem o uso de defensivos químicos, o sistema de produção orgânico apresenta-se em expansão. O trabalho avaliou a eficácia dos tratamentos de sementes de ervilha no controle de A. pisi de acordo com o sistema orgânico. Foram testados biofungicidas comerciais, microrganismos cultivados em laboratório e extratos vegetais, indutores de resistência, métodos físicos baseados na termoterapia (vapor aerado e água aquecida), e elétrons de baixa energia e a associação dos tratamentos físicos e controle biológico, num total de cinco experimentos. Utilizaram-se sementes de ervilha naturalmente infectadas por Ascochyta pisi, semeadas em substrato orgânico comercial esterilizado e mantidas em casa-de-vegetação. Avaliaram-se emergência e índice de infecção duas semanas após a semeadura. O índice de infecção das plantas foi calculado em diferentes classes de infecção de acordo com Townsend-Heuberger, (1943). Extrato vegetal de Thymus vulgaris, Clonostachys rosea IK 726 e Micosat (Glomus sp. + Pseudomonas fluorescens + P. borealis + Bacillus subtilis), e a associação de tratamento físico com elétrons de baixa energia a 130 e 140 kV com o agente biológico Bacillus subtilis (Serenade) proporcionaram níveis de controle equivalentes ao tratamento químico

The enzyme carbonic anhydrase (CA), catalysing the interconversion between CO2 and HCO3', has long been known to be present in plants as well as in animals. Several of the animal isozymes, but none of the plant CAs, have been extensively studied. When the first plant CA cDNA sequences were published in 1990, it was obvious that the animal and plant CAs represent evolutionarily distinct families with no significant sequence homology between the families. Pea CA is synthesised as a precursor and subsequently processed at the import into the chloroplast. When we purified CA from pea leaves two oligomeric forms with molecular masses around 230 kDa were obtained. One form was homogenous while the other form contained subunits of two different sizes. The larger subunit has an acidic and highly charged N-terminal extension, consisting of 37 residues. We propose that the sequence that precedes the cleavage site resulting in the large subunit represents the functional transit peptide, directing CA to the chloroplast. Neither the transit peptide nor the acidic 37-residue peptide were found to affect the folding, activity or oligomerisation of pea CA. Kinetic investigations showed that pea CA requires a reduced environment and high concentrations of buffer for maximal catalytic activity. High buffer concentrations result in a faster turnover of the enzyme (kcat) while the efficiency (kcatlKm) is not affected. This is consistent with a ping-pong mechanism with the buffer as the second substrate. Both kcat and kcatlKm increase with pH but the dependences cannot be described by simple titration curves. SCN' is an uncompetitive inhibitor at high pH and a noncompetitive inhibitor at neutral and low pH. This is in accordance with the mechanistic model, previously proposed for human CAM, involving a zincbound water molecule as a catalytic group. In this model, the carbon dioxide - bicarbonate interconversion, reflected by kcatlKm, is temporally separated from a rate limiting proton-transfer step. At high pH, solvent hydrogen isotope effects obtained for pea CA agree with this scheme, while they do not fit at neutral and low pH. Site-specific mutations of cysteine residues at positions 165, 269 and 272 were difficult to study, either because strong deviations from Michaelis-Menten kinetics were observed, or because the mutants were found in inclusion bodies. However, the mutant H208A was found to be a very efficient enzyme with the highest kcatlKm value obtained for any CA so far, 2.9-108 M'1s '1. With the H208A mutant an increased dependence on high buffer concentrations at low pH was obtained. At high pH, the mutant is more efficient than the unmutated enzyme. The H208A mutant is also more prone to oxidation than the wild-type enzyme. / <p>Diss. (sammanfattning) Umeå : Umeå universitet, 1994, härtill 4 uppsatser</p> / digitalisering@umu

The developmental programs of maturing seed and fruit in pea (Pisum sativum L.) are tightly controlled by the interactions of several phytohormones, including gibberellins (GAs), auxins, and abscisic acid (ABA). To more fully understand these hormone networks and their roles in controlling development, transcription profiles of GA metabolism genes and metabolite profiles of key GAs, auxins, and ABA were determined in developing seeds, and histological studies were employed to correlate physiology and hormone metabolism. Data suggest that bioactive GA stimulates several aspects of seed growth, and ABA appears to promote bioactive GA1 synthesis in rapidly growing seed coats, and inhibit GA biosynthesis in the embryo axes of maturing embryos. Two putative auxin receptor genes were cloned, and their transcription profiles examined in developing seed and pericarp tissues. Pericarp PsAFB6A transcription was responsive to auxin and seed signals, indicating a potential role for the modulation of auxin sensitivity in fruit development.

Pterocarpan phytoalexins are antimicrobial compounds produced by legumes when challenged by biotic stresses. Most legumes produce pterocarpan phytoalexins with (-)-stereochemistry but pea (Pisum sativum L.) produces as its major phytoalexin (+)-pisatin. Pea also occasionally produces a minor amount of (-)-maackiain as a pterocarpan phytoalexin, and studies on the biosyntheses of (+)-pisatin and (-)-maackiain have shown that up to (-)-7,2'-dihydroxy-4',5'-methylenedioxyisoflavanone [(-)-sophorol] and 7,2'-dihydroxy-4',5'-methyl-enedioxyisoflavanol [(-)-DMDI]they have common intermediates with (-)-DMDI being where the two pathways diverge. The final step in (+)-pisatin biosynthesis is the methylation of (+)-6a-hydroxymaackiain [(+)-6a-HMK] by 6a-hydroxymaackiain methyltransferase (HMM2) but the steps from (-)-DMDI to (+)-6a-HMK are unknown.The shifting of the stereochemistry from (-)-DMDI to (+)-6a-HMK has been proposed to involve the achiral isoflavene, 7, 2'-dihydroxy-4', 5'-methylene-dioxyisoflav-3-ene (DMDIF). In this dissertation, I have shown that cis-(-)-DMDI is the enzymatic product of (-)-sophorol, and is the precursor of DMDIF which is produced by the dehydration activity of "isoflavene synthase" (IFVS). IFVS activity was not observed in elicited tissues of alfalfa, chickpea, beans, pepper, and broccoli, plants that do not produce (+) pterocarpans. Partial purification of IFVS demonstrated that it is either large in size or tightly complexed with other proteins. The SDS-PAGE of the 29-fold purified product revealed 12 major bands that aggregated into 3 bands in the non-denaturing PAGE. IFVS activity was in band 3 which co-migrated with marker proteins of>100 kDa in size. Proteins identified from LC-MS/MS peptide sequences of the proteins in band 3, when compared to three protein databases, did not identify any proteins with an enzymatic activity expected for IFVS. A disease resistance-response protein (a dirigent-like protein) and two protein-binding proteins were the most abundantly detected proteins in the pea transcriptome-translated database. Also, four of the known enzymes (isoflavone reductase, HMM1, HMM2, and sophorol reductase) involved in (+)-pisatin biosynthesis were among the proteins identified. It may be that IFVS is associated with these other proteins as a complex in vitro and in vivo. The lack of detection of IFVS in the databases could be because it has not yet been sequenced as it functions in a rare biosynthetic pathway.

No description available.

Made available in DSpace on 2014-06-11T19:30:24Z (GMT). No. of bitstreams: 0 Previous issue date: 2010-08-16Bitstream added on 2014-06-13T18:40:30Z : No. of bitstreams: 1 machado_cg_dr_botfca.pdf: 685636 bytes, checksum: 7c0e6ecdc3b569488fe111188298b1c3 (MD5) / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / A qualidade da semente na produção agrícola é um dos principais fatores a ser considerado na implantação da cultura, havendo consenso sobre a importância da germinação, do vigor das sementes e da necessidade de avaliá-los. O trabalho teve como objetivo estabelecer metodologias para os testes de germinação e vigor com ênfase no teste de condutividade elétrica para a avaliação da qualidade fisiológica de sementes de ervilha forrageira (Pisum sativum subsp. arvense). Para estabelecer a metodologia do teste de germinação utilizou-se quatro lotes sendo dois da cultivar IAPAR 83 e dois da BRS Forrageira. Foram testadas cinco temperaturas (15ºC, 20ºC, 25ºC, 20-30ºC e 15-25ºC) e dois substratos (areia e papel). Para a metodologia para o teste de condutividade elétrica foram utilizados dez lotes da cultivar IAPAR 83. Foram realizados os testes de germinação, primeira contagem de germinação, emergência de plântulas em casa de vegetação para caracterização dos lotes e estudos específicos para os testes de condutividade elétrica (temperaturas de 20ºC e 25ºC, volumes de 75mL e 250mL de água, 50 sementes, e períodos de 8, 16, 20, 24 e 28 horas). Concluiu-se que o teste de germinação para ervilha forrageira deve ser conduzido a 20ºC em rolo de papel com primeira contagem e contagem final ao 4º e 7º dia, respectivamente. O teste de condutividade elétrica utilizando 50 sementes embebidas em 250 mL de água, na temperatura de 25ºC por 24 horas mostrou-se promissor para a diferenciação de lotes de sementes de ervilha forrageira / Seed quality is an important role in the establishment of crops. It is consensual that seed germination and vigor are important tools for the production process and must be evaluated. The present research had as objective to establish methodologies for the germination and electrical conductivity tests to evaluate physiological quality of forage pea seeds (Pisum sativum subsp. arvense). Two lots of the cultivar „IAPAR 83‟ and two lots of the cultivar „BRS Forrageira‟ were used to establish the methods for the germination test. Five temperatures (15ºC, 20ºC, 25ºC, 20-30ºC and 15-25ºC) and two substrates (between sand and rolled paper towel) were tested. Ten lots of the cultivar „IAPAR 83‟ were studied to establish the methodology for the electrical conductivity test. Germination, first count of germination and seedling emergence in greenhouse were studied. For the electrical conductivity test, different temperatures (20ºC and 25ºC), water volumes (75 mL and 250 mL) and imbibition periods (8, 16, 20, 24 and 28 hours) were evaluated. It was concluded that the germination test for forage pea seeds must be carried out under 20ºC and in rolled paper towels with first counting and final counting to the 4 and 10 days after sowing, respectively. The electrical conductivity test is sensitive to differentiate seedlots of forage pea whenever conducted with 50 seeds imbibed in 250 mL of water under 25ºC for 24 hours