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This study investigated the effect of water potential on soil microbial C and N pools. Two soil types were treated with additions of salt solution to establish osmotic water potentials, and by ceramic plate - pressure chamber apparatus to establish matric water potentials. Soils were then subjected to short-term incubations. Soil microbial C and N contents (BC and BN) were measured mainly by the fumigation-extraction and fumigation-incubation methods. Results showed that both Microbial C and N pools were markedly affected by soil water potential. The soil microbial C content always showed an increase with increasing water stress and then a decrease beyond a threshold value of water stress, compared to the microbial C content at a control water potential of -0.03 MPa (-0.3 Bar). This response pattern to water stress was true, not only for osmotic stress, but also for matric stress, and regardless of the osmotic agent employed. The response pattern of the microbial N pool to water stress generally contrasted with that of the C pool, and depended on the osmotic strength of the extraction solution (K₂SO₄) used in the determination. Non-isotonic extraction after fumigation resulted in a decrease in microbial N content with increasing water stress, while isotonic extraction resulted in an increase with increasing water stress, beyond a threshold value of water stress. Soil microbial C/N ratio always increased with increasing water stress. Matric water stress had a more marked effect on BC and BN than osmotic stress. The possible reasons for the response patterns of BC, BN and microbial C/N ratio have been discussed in this thesis. Some suggestions on the methodology of microbial biomass measurement for water stressed soil samples have been made, and mainly relate to the biomass fumigation techniques and possible changes in the Kc, Kce and Kn values under water stress, and to the substrate induced respiration (SIR) method and suppressed respiration under water stress.

NaCl-induced and -repressed cDNA clones had previously been isolated by differential screening of a cDNA library, prepared from poly(A(^+)) RNA isolated from Distichlis spicata (salt grass) cell cultures grown in the presence of 260 mM NaCl (Zhao, et al., 1989). Eight of these cDNA clones have now been subcloned and/or sequenced and the predicted polypeptides compared with owl sequence data base. Three clones pDZ6.2, pDZVIII 1.2.1 and pDZIX 3.1 encode proline rich proteins, containing an amino acid repeat [PPKKDH(H)Y(Y)]. They have similar amino acid usage to proline-rich cell wall proteins, being rich in P, K, H and Y. The first 20 amino acid residues encode a putative leader sequence, supporting the proposed extracellular role as a cell wall protein. This N-terminal sequence (MPLLVALLLVLAVVAAAGAD) shares some similarity with die leader sequence of a soyabean proline-rich cell wall protein precursor and other extracellular proteins (the conserved residues are underlined). There is an increase in abundance of transcripts hybridising to the inserts from pDZ6.2 and pDZVUI 1.2.1 in response to either 520 mM NaCl or 100 µM ABA, but a decrease in response to 5 mM exogenous proline. It is suggested that the corresponding gene(s) are regulated at the level of either transcription or transcript stability, in response to elevated NaCl, with ABA as a mediator of (or part of) tills response. pDZ6.2 and pDZXI 3.1 have identical nucleotide sequences, whilst pDZVni 1.2.1 differs in three base paks within the putative open reading frame, suggesting that there may be at least two members of a multi gene family. A 68 bp OA repeat has been found in the 5' untranslated region of pDZ6.2 and a corresponding transcript identified by northern analysis using this OA sequence as a probe. Such nucleotide repeats can form triplexes (DNA) or hakpin loops (RNA), which is dependent on pH and ionic conditions. Therefore this OA repeat may play a role in the regulation of the gene corresponding to pDZ6.2 at the level of transcription or translation, possibly by attenuation of these processes, either by the formation of triplexes or hah-pins, or the binding of a protein to this GA region, at low ionic strength. However initial in vitro ttanscription experiments, to compare the transcriptional activity of pDZ6.2 and pDZVin 5.1.1 at different ionic strengths, proved inconclusive. An attempt was also made to identify the corresponding genomic region from D. spicata by anchored PGR.A fourth clone pDZ2.8L encodes a histone 2B protein, having 97.9% similarity to a wheat histone 2B. Its transcript abundance decreased in response to either 520 mM NaCl, 5 mM proline or 100 µM ABA. The sequences of the remaining clones either revealed no significant similarity to any known sequences or were assigned as being cloning artefacts .D. spicata cells accumulate proline within eight hours of exposure to 260 mM NaCl (Heyser, et al., 1989b). An unsuccessful attempt was also made to isolate a pyrroline-5- carboxylate reductase gene homologue from D. spicata, by heterologous probing of Southern blots with a soyabean cDNA pProCl and PCR.

Submitted by (ana.araujo@ufrpe.br) on 2017-02-10T14:18:44Z No. of bitstreams: 1 Gabriela de Morais Guerra Ferraz.pdf: 1062151 bytes, checksum: b0123f5d7101341f981de975826dc25b (MD5) / Made available in DSpace on 2017-02-10T14:18:44Z (GMT). No. of bitstreams: 1 Gabriela de Morais Guerra Ferraz.pdf: 1062151 bytes, checksum: b0123f5d7101341f981de975826dc25b (MD5) Previous issue date: 2008-02-29 / Conselho Nacional de Pesquisa e Desenvolvimento Científico e Tecnológico - CNPq / The Northeast of Brazil, major national producer of bananas, presents as a major limiting factor the stretch of saline soil. The urgency in the development of tolerant cultivars to salinity has led to breeding programs with the aimed to differ the bananas cultivars in diploid genotypes tolerant and sensitive, to be considered viable genetic material for pollination of triploid and tetraploid cultivars. Generally, the present study aimed to characterize diploid genotypes belonging to the AA banana genomic group on salinity and identify genes differentially expressed in contrasting genotypes. At first, this research assessed the growth and accumulation of inorganic ions in 19 diploid genotypes (AA) of bananas subjected to salt stress. The genotypes were grown in a greenhouse and submitted to irrigation with no saline water (0 mM NaCl) or with saline water (100 mM NaCl) for a period of 21 days, when the experiment was collected. To the physiological evaluation, were considered the parameters of growth:leaf area, height, number of leaves, diameter of the pseudostem, weight of the tax burden of fresh and dry, while the chemical assessment observed the concentration of sodium ions, potassium, chloride, magnesium and calcium in limbo leaf, and root pseudostem / subroot. The addition of NaCl to the cultivar solution has, in general, reduced the growth expressed by height, formation of new leaves, leaf area, diameter of the pseudostem and production of fresh and dry materials. This reduction in growth probably due to factors such as: the toxic effect of ions that have been absorbed, the low osmotic and water potential of the cells as well as the use of metabolic energy in the process of osmotic adjustment. In assessing chemical factors, it was possible to observe that the ions concentration has been preferentially presented in root tissue, showing that it is a culture moderately tolerant to salinity.The sodium and chlorine ions increased significantly with the salt increase in differentparts of the plant, while potassium suffered reduction in the leaf lamina and the pseudostem probably because it is associated to the competition with the sodium ion leading to the conclusion that the differential accumulation of ions potentially toxic (sodium and chlorine) and the maintenance of potassium, contribute to the tolerance to salinity in banana. From the physiological analysis and by means of the toxicity symptoms caused by NaCl, it was possible to observe that the effects were less intense in Birmania and Khai Nai On genotypes, than in Sowmuk, its indicates the possibility of use of this plants in programmes for cultivars improvement as tolerant and sensitive, respectively. Seven genotypes were selected for characterization by means of molecular markers RAPD, with the aim to link the physiological responses to salt stress with the formation of groups. We tested 16 random primers. The resultsshow a broad molecular genetic variability among seven genotypes studied. The formation of groups, in part is related to the data obtained in the physiological assessment, keeping in the same group the Birmania and Khai Nai On genotypes.These genotypes that showed higher tolerance to salt stress, when compared to the more salt-sensitive genotype (Showmuk), became distant genetically, so, it can be noticed the possibility of use of this molecular marker in the study of genetic diversity for this species. For the genome functional study, or transcriptoma, this study aimed the detection of possible changes in the pattern of genes expressed in the three diploid genotypes (AA) of banana, Khai Nai On, Burma and Sowmuk with contrasting results when in the absence and presence of high salt concentrations. The Differential Display PCR - ddPCR technique was used to identify and compareregions of bands from fragments of cDNA on agarose gel. A total of 43 fragments of differentially expressed cDNA was generated from the combination of four primers anchors and six random primers. Among the transcripts, 30 were once expressed by the genotype Burma and Kha Nai On, and 13 only by Sowmuk genotype. Theregions of bands with greater consistency of formation, is between 4000 bp and 150 bp. By the results of this research, it was possible to identify some fragments potentially involved to the condition of salinity in banana. The isolation, purification and sequencing of these - Expressed sequence tags - ESTs can assist in the development of new varieties of banana, more adapted to salt stress, in addition to enriching the database of public functional sequences of genomes banks. / O Nordeste do Brasil, maior produtor nacional de banana, apresenta como fator limitante a grande extensão de solos salinos. A urgência no desenvolvimento de cultivares tolerantes a salinidade tem levado programas de melhoramento genético da cultura a classificar os genótipos diplóides de bananeira em tolerantes e sensíveis, por serem considerados materiais genéticos viáveis para polinização de cultivares triplóides e tetraplóides. De modo geral, o presente trabalho buscou caracterizar genótipos diplóides pertencentes ao grupo genômico AA de bananeira quanto a salinidade além de identificar genes diferencialmente expressos nos genótipos contrastantes. Na primeira fase desta pesquisa, foi avaliado o crescimento vegetativo e o acúmulo de íons inorgânicos em 19 genótipos diplóides (AA) de bananeiras submetidas a estresse salino. Os genótipos foram cultivados em casa de vegetação e submetidos à irrigação com água não salina (0 mM de NaCl) ou águasalina (100 mM de NaCl) durante um período de 21 dias, quando foi coletado o experimento. Para a avaliação fisiológica, foram considerados os parâmetros de crescimento: área foliar, altura, nº de folhas, diâmetro do pseudocaule, peso da matéria fresca e peso da matéria seca; enquanto que a avaliação química observou a concentração dos íons sódio, potássio, cloro, magnésio e cálcio no limbo foliar, pseudocaule e raiz/rizoma. A adição de NaCl à solução de cultivo, provocou, de modo geral, redução no crescimento expresso pela altura, formação de novas folhas, área foliar, diâmetro do pseudocaule e produção de matéria fresca e seca, provavelmente devido a fatores como: o efeito tóxico dos íons que foram absorvidos; o baixo potencial osmótico e hídrico das células; bem como a utilização de energia metabólica no processo de ajustamento osmótico. Na avaliação química, foi possívelobservar que a concentração dos íons foi preferencialmente no tecido radicular, reafirmando tratar-se de uma cultura moderadamente tolerante a salinidade. Os íonssódio e cloro aumentaram significativamente frente ao incremento salino nas diferentes partes da planta, enquanto o potássio sofreu redução no limbo foliar e no pseudocaule, possivelmente por estar associado a competição com o íon sódio levando a conclusão de que o acúmulo diferencial de íons potencialmente tóxicos (sódio e cloro) e a manutenção do potássio, contribuem para a tolerância à salinidade em bananeira. A partir da análise fisiológica e por meio da sintomatologia de toxidez provocada pelo NaCl, foi possível observar que os efeitos foram menos intensos nos genótipos Birmânia e Khai Nai On, do que no Sowmuk, indicando possíveis plantas a serem utilizadas nos programas de melhoramento da cultura como tolerantes e sensível, respectivamente. Sete genótipos foram selecionados para caracterização por meio de marcadores moleculares RAPD, buscando-se relacionar as respostas fisiológicas ao estresse salino com a formação de grupos.Foram testados 16 primers randômicos. Os resultados moleculares mostram uma ampla variabilidade genética entre os sete genótipos estudados. A formação dos agrupamentos, em parte correspondeu aos dados obtidos na avaliação fisiológica, mantendo em um mesmo grupo os genótipos Birmânia e Khai Nai On. Estes genótipos que apresentaram maior tolerância ao estresse salino, quando comparados com a mais sensível ao sal (Showmuk), mostraram-se distantes geneticamente, o que vem a demonstrar a possibilidade de utilização deste marcador molecular no estudo da diversidade genética para esta espécie. Para o estudo do genoma funcional, ou transcriptoma, o presente trabalho objetivou a detecção das possíveis alterações no padrão de genes expressos nos três genótipos diplóides (AA) de bananeira, Khai Nai On, Birmânia e Sowmuk, com respostascontrastantes quando na ausência e presença de alta concentração salina. A técnica de Differential Display PCR – ddPCR foi utilizada para identificar e comparar regiões de bandas de fragmentos de cDNA em gel de agarose. Um total de 43 fragmentosde cDNA diferencialmente expressos foram gerados a partir da combinação de quatro primers âncoras e seis primers aleatórios. Dentre os transcritos, 30 foram expressos unicamente pelos genótipos Birmânia e Kha Nai On, e 13 apenas pelo genótipo Sowmuk. As regiões de bandas com maior consistência de formação, encontraram-se entre 4000 pb e 150 pb. Pelos resultados deste trabalho, foi possível identificar alguns fragmentos potencialmente envolvidos em respostas à condição de salinidade em bananeira. O isolamento, purificação e sequenciamento destes –Expressed sequence tags - ESTs poderá auxiliar no desenvolvimento de novos cultivares de bananeira, mais adaptados ao estresse salino, além de enriquecer a base de dados de bancos públicos de seqüências de genomas funcionais.

京都大学 / 0048 / 新制・課程博士 / 博士(農学) / 甲第18694号 / 農博第2091号 / 新制||農||1029(附属図書館) / 学位論文||H27||N4888(農学部図書室) / 31627 / 京都大学大学院農学研究科地域環境科学専攻 / (主査)教授 舟川 晋也, 教授 縄田 栄治, 教授 間藤 徹 / 学位規則第4条第1項該当 / Doctor of Agricultural Science / Kyoto University / DFAM

Submitted by Lara Oliveira (lara@ufersa.edu.br) on 2017-02-01T20:26:32Z No. of bitstreams: 1 AndréMO_TESE.pdf: 5450289 bytes, checksum: 5882a0a67b8d1b236c9a9b7e9ec60dfb (MD5) / Approved for entry into archive by Vanessa Christiane (referencia@ufersa.edu.br) on 2017-03-21T14:53:28Z (GMT) No. of bitstreams: 1 AndréMO_TESE.pdf: 5450289 bytes, checksum: 5882a0a67b8d1b236c9a9b7e9ec60dfb (MD5) / Approved for entry into archive by Vanessa Christiane (referencia@ufersa.edu.br) on 2017-03-21T15:07:13Z (GMT) No. of bitstreams: 1 AndréMO_TESE.pdf: 5450289 bytes, checksum: 5882a0a67b8d1b236c9a9b7e9ec60dfb (MD5) / Made available in DSpace on 2017-03-21T15:07:20Z (GMT). No. of bitstreams: 1 AndréMO_TESE.pdf: 5450289 bytes, checksum: 5882a0a67b8d1b236c9a9b7e9ec60dfb (MD5) Previous issue date: 2016-07-15 / In spite of the fact that crystalline basement predominates with brackish water wells in Brazilian thirstland, desalination technology by reverse osmosis enables its potabilization. Since the late nineties, reverse osmosis desalination devices have been deployed in order to meet the water demand for human consumption, especially in the rural Northeast. Nevertheless, difficulties are present in such deployment like lack of operation and proper maintenance, causing stoppage thereof and producing high-level reject brine, which is usually discharged to the ground without any criteria, and its main consequence has been soil salinity increase over time. Thus, this works aims at evaluating the outcome of the reverse osmosis desalination discharge and its influence in physicochemical attributes of distinct receiver soils in rural communities from Potiguar west. This research was conducted between 2013 and 2014. At first, the communities which were supplied by catchment and treatment of desalinated water centers were registered through a cadastral survey. In order to do so, four data collection expeditions took place in different periods, raining season and drought, on the soils receiving reject brine. Three distances were used (0, 1 and 2 meters from the discharge points) with two layers for each point (0-20cm and 20-40 cm) as well as the evaluation of a) the reverse osmosis treated water quality, b) the well, c) the reject brine. Physicochemical attributes of water for irrigation was also analyzed as well as soil samples for a fertility evaluation. Data were subjected to statistical average tests by Scott Knott to verify the behavior within the points and layers according to each period and between all four periods. The waters were classified according to its use for irrigation; leakage risks and toxicity in plants. The soils were classified according to salinity, Ph considering CE and PST. In the monitored rural communities, the reversed osmosis water treatment stations produce desalinated water with low concentrations of salts, with 68% of all samples are in C1S1 rating class; 25% in C2S1 and class; only 7% in C3S1 class. Regarding the reject brine, 93% of waste water samples were classified as C3 or C4 during the four collecting periods, that is, at high or extremely high salinization risk. The different types of receiver soils of reject brine coming from such communities show meaningful alteration of their attributes and of their qualities throughout the periods, being that more noticeable during the drought periods and on the layers of soils with greater amount of clay, promoting different ratings for the same soil, being such ratings influenced directly by the waste water from desalination process / Ainda que, no Semiárido brasileiro, predomine o embasamento cristalino, com poços de água salobra, a tecnologia da dessalinização permite a sua potabilização. Desde o final da década de 1990, vem sendo implantados equipamentos de dessalinização por osmose reversa visando o atendimento da demanda hídrica para consumo humano, especialmente na zona rural do Nordeste. No entanto, dificuldades estão presentes na implantação dos equipamentos, tais como a falta de operação e manutenções adequadas que causam a paralisação dos mesmos, e a produção de rejeitos com elevados teores de sais, normalmente despejados ao solo sem qualquer critério, cujo maior impacto tem sido o aumento da salinidade do solo ao longo do tempo. Desta forma, o objetivo deste trabalho foi avaliar o rejeito gerado pela osmose reversa e sua influência nas alterações dos atributos físico-químicos de distintos solos receptores em comunidades rurais do Oeste Potiguar. A pesquisa ocorreu no período de 2013 e 2014, inicialmente, foram identificadas as comunidades abastecidas com as unidades de captação e tratamento de água por dessalinização, por meios de um levantamento cadastral. Para isto, foram realizadas 4 campanhas de coletas em diferentes períodos de seca e chuva nos solos receptores do rejeito salino, usando três distâncias (0; 1 e 2 metros do ponto de despejo), com duas camadas para cada ponto (0-20 e 20-40 cm), bem como avaliação da qualidade das águas tratadas por osmose reversa, poço e rejeito salino, dentro de cada período. Foram analisados atributos físico-químicos das águas para fins de irrigação e as amostras de solo para avaliação da fertilidade. Os dados foram submetidos a testes estatísticos de médias, por Scott Knott, verificando o comportamento dentro dos pontos e camadas de cada período e entre os 4 períodos. As águas foram classificadas quanto ao uso na irrigação; aos riscos de infiltração e toxicidade em plantas. Os solos foram classificados de acordo com a salinidade, considerando pH, CEes e PST. As estações de tratamento de água por osmose reversa nas comunidades rurais monitoradas produzem uma água dessalinizada com concentrações baixas de sais, com 68% do total das amostras estão na classe de classificação C1S1; 25% na classe C2S1 e; apenas 7% na classe C3S1. Com relação ao rejeito gerado, 93% das amostras de água de rejeito se classificaram como C3 ou C4 nos quatro períodos de coleta, ou seja, águas de alto ou extremamente alto risco de salinização. As diferentes classes de solos receptores do rejeito salino das comunidades apresentaram alterações significativas dos seus atributos e sua qualidade ao longo dos períodos, sendo mais evidente nos períodos secos e camadas de solos com maior presença de argila, promovendo classificações distintas para um mesmo solo, influenciadas diretamente pela água de rejeito do processo de dessalinização / 2017-02-01

From the Proceedings of the 1971 Meetings of the Arizona Section - American Water Resources Assn. and the Hydrology Section - Arizona Academy of Science - April 22-23, 1971, Tempe, Arizona / The pre-Columbian Hohokam Indians occupied the major river drainages of central Arizona, and have been the subject of much intense archaeological research. Evidence indicates that the Hohokam began using river water for crop irrigation about 300 B.C., and modified and improved their irrigation systems over time, until the maximum extent of these systems was achieved about 900 a. D. Two types of water control seem to have been utilized: (1) the direct exploitation of rivers through the use of irrigation canals, (2) indirect use through controlled runoff within microdrainages at higher elevations before it reached the rivers. At first, probably only those parcels of land with optimal soils and drainage were used, but apparently population increases fostered by agriculture itself, combined with increasing social and political complexity, necessitated more and more exploitation of marginal lands. Eventually soil problems increased, imposing severe limitations on agriculture. These involved salt and alkali accumulation due to inadequate drainage, soil density and water logging. Additionally, the extension of cropping required the clearing of natural vegetation, which resulted in increased erosion and decreased available native food resources for periods when crops failed. The culture vanished completely about 1450 a. D., probably mainly because of their manner of river exploitation for irrigation. More recent archaeological studies are concentrating not only on river use but also on river abuse.