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Uso de mutantes fotomorfogenéticos no estudo da competência para regeneração in vitro em micro-tomateiro (Lycopersicon esculentum CV Micro-Tom.; Use of photomorphogenenic mutants in the study of the competence for in vitro regeneration in micro-tomato (lycopersicon esculentum cv micro-tom).

Carvalho, Rogério Falleiros
Fonte: Biblioteca Digitais de Teses e Dissertações da USP Publicador: Biblioteca Digitais de Teses e Dissertações da USP
Tipo: Dissertação de Mestrado Formato: application/pdf
Publicado em 22/01/2004 PT
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Paralelamente ao modelo Arabidopsis thaliana, o tomateiro (Lycopersicon esculentum) tem sido crescentemente utilizados em abordagens genéticas de questões fisiológicas. Uma das principais vantagens de Arabidopsis como “planta de laboratório” tem sido seu pequeno porte e ciclo de vida curto. Contudo, a cultivar Micro-Tom (MT) de tomateiro possui tamanho muito reduzido (8 cm) e pode produzir até 5 gerações por ano. Mutantes fotomorfogenéticos em tomateiro deficientes na síntese do cromóforo do fitocromo (au), mutantes deficientes na síntese das apoproteínas PHYA e PHYB1 (fri e tri, respectivamente) e mutantes superexpressando o fitocromo (hp, atv e Ip) constituem-se em um modelo para estudos da fotomorfogênese. No que se refere à capacidade de regeneração in vitro como uma resposta fotomorfogenética, poucos trabalhos têm sido realizados. O presente trabalho teve como objetivo transferir as mutações au, fri, tri, hp, Ip e atv, bem como o locus de regeneração (Rg1) da cultivar MsK, para a cultivar Micro-Tom. As linhagens obtidas foram utilizadas para verificar o efeito da fotomorfogênese na competência para regeneração in vitro. Para tanto, foram realizados tratamentos com luz branca, vermelho (V) e vermelho-extremo (VE) em explantes radiculares...

Adaptação do modelo LINTUL (Light Interception and Utilization) para estimação da produtividade potencial da cultura de soja; Adaptation of LINTUL model (Light Interception and Utilization) to estimate soybean potential production

Corrêa, Simone Toni Ruiz
Fonte: Biblioteca Digitais de Teses e Dissertações da USP Publicador: Biblioteca Digitais de Teses e Dissertações da USP
Tipo: Dissertação de Mestrado Formato: application/pdf
Publicado em 23/01/2009 PT
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Em 2007 o complexo de soja foi responsável por 19 por cento do total das exportações do agronegócio brasileiro, gerando mais de U$11 bilhões em divisas. Projeções indicam que até 2020 o Brasil deverá produzir 105 milhões de toneladas de soja, ou 81 por cento a mais do que a atual produção. Apesar de incidir sobre a produtividade a maior expectativa de crescimento, espera-se que a expansão significativa em área ocorra nas regiões de baixa latitude dos Cerrados, e em especial, no estado do Mato Grosso. É fundamental a determinação de estratégias que considerem produção, dimensões econômicas e ambientais. O uso da modelagem agrícola é a única forma de explorar sistematicamente o potencial produtivo em escala global e predizer produtividades futuras em determinadas condições. A utilização de computadores e banco de dados torna-se uma ferramenta cada vez mais necessária, no sentido de disponibilizar rapidamente informações de qualidade a um custo relativamente inferior, quando em comparação a experimentos de campo. O modelo LINTUL, desenvolvido pela Universidade de Wageningen, foi extensamente utilizado para predizer a produtividade potencial de culturas baseado no uso eficiente da radiação solar, sob condições ótimas de desenvolvimento. A cultura de soja...

Respostas morfofisiológicas de genótipos de Brachiaria spp. sob duas intensidades de desfolhação e modelagem da produção de forragem em função das variações estacionais da temperatura e fotoperíodo: adaptação do modelo CROPGRO; Morphological and physiological responses of Brachiaria spp. grasses under two defoliation intensities and modeling forage yield as a function of seasonal variations of temperature and daylength: adaptation of the CROPGRO model

Lara, Márcio André Stefanelli
Fonte: Biblioteca Digitais de Teses e Dissertações da USP Publicador: Biblioteca Digitais de Teses e Dissertações da USP
Tipo: Tese de Doutorado Formato: application/pdf
Publicado em 15/04/2011 PT
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Para poder compreender e descrever o crescimento das plantas forrageiras é necessário ter conhecimento acerca de seus aspectos agronômicos e morfofisiológicos e suas respostas aos fatores edafoclimáticos. O desenvolvimento de ferramentas que viabilizem a racionalização dessas inter-relações é de grande importância para a comunidade científica, ao facilitar a explicação da dinâmica do crescimento, e para o pecuarista dando opções de planejamento e auxílio à tomada de decisão na propriedade pecuária. O objetivo deste trabalho foi avaliar as respostas agronômicas e morfofisiológicas de cinco genótipos de Brachiaria spp. e gerar modelos de crescimento baseados em soma térmica e fotoperíodo além de adaptar o modelo CROPGROForragem, visando explorar esses recursos computacionais para estabelecer uma base racional de manejo desses capins. Foram estudados quatro genótipos de Brachiaria brizantha (Hochst. ex A. Rich.) Stapf (Marandu, Xaraés, Arapoty e Capiporã) e uma de B. decumbens Stapf (cv. Basilisk) colhidos a 15 e 7,5 cm durante onze ciclos distribuídos em um ano. As unidades experimentais (parcelas de 9 x 4 m) foram irrigadas e adubadas com o equivalente a 220 kg ha-1 ano-1 de N e K2O. O delineamento experimental foi de blocos completos casualizados em parcelas subdivididas com quatro repetições. Foi calculada a produção total e estacional de forragem. Foram monitoradas uma rebrotação de verão e de inverno...

Autoecologia de Bauhinia holophylla Steud. (Leguminosae-Caesalpiniolideae), na Reserva Biologica e Estação Experimental de Moji Guaçu, SP

Josimara Nolasco Rondon
Fonte: Biblioteca Digital da Unicamp Publicador: Biblioteca Digital da Unicamp
Tipo: Tese de Doutorado Formato: application/pdf
Publicado em 24/02/2006 PT
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Uma população de Bauhinia holophylla Steud. localizada no cerrado sensu stricto da Reserva Biológica e Estação Experimental de Moji Guaçu (RBEE de Moji Guaçu) foi estudada quanto a sua fenologia reprodutiva, expectativa de vida foliar, predação de sementes, germinação, fotoperíodo e regeneração natural. O padrão de distribuição da população adulta e jovem de B. holophylla, na área estudada é do tipo agregado. A população jovem e adulta de B. holophylla na RBEE de Moji Guaçu pode ser considerada juvenil, concentrando a maioria dos indivíduos nas primeiras classes de crescimento em altura e diâmetro. A expectativa média de vida da folha no primeiro ano de estudo foi de 8,2 meses, enquanto no segundo ano foi de 7,6 meses. A produtividade primária da fração folhas de 21 plantas de B. holophylla amostradas foi mais intensa nos meses de julho a agosto, durante o período de estudo (dois anos), portanto, durante a estação seca. A fração flores e botões esteve associada ao período da estação chuvosa, com produção maior nos meses de novembro a janeiro. A mortalidade foliar coincidiu com o período de menor precipitação na estação seca. A queda total das coortes foliares ocorreu ao mesmo tempo, na estação seca...

Influência lunar sobre plantas hortícolas

Simão,Salim
Fonte: Universidade de São Paulo; Escola Superior de Agricultura Publicador: Universidade de São Paulo; Escola Superior de Agricultura
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/01/1958 PT
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The aim of this paper is the study of moon effects on ten different crops divided in four groups: 1) salad and cole crops (lettuce, endive, cabbage, cauliflower); 2) root crops (beet, carrot, radish, turnip); 3) bulb crops (onion); 4) solanaceous fruits (eggplant). The design of the experiment was randomized blocks, with four replications, the different treatments being the four phases of the moon. The analyses of variance are given in the work of Simão (1953) and the analises of the mean in tables 1 to 2. The main conclusions are: 1) No difference in production were found related to different moon phases, even it the crops supposed to be sensible to moon effects. 2) In a few cases, where some increase in production was observed, such increase could be atributed by other apents 3) The agents supposed to interfere with increase in production were temperature and photoperiodism, rather than moon phases. 4) The most sensible crops to low temperature, during the night, were: lettuce, endive, cauliflower, cabbage, carrots, turnips and radish. 5) The most sensible crops to both low temperature and photoperiodism were: onion and beet. 6) The moon phases supposed to have opposed effects, namely full-moon and half-moon, gave mixed results sometimes both giving the best yield simultaneously and sometimes giving the poorest crops. 7) As a final conclusion...

Estudo de desenvolvimento de Viguiera robusta Gardn., uma Asteraceae do cerrado

Ruggiero,Patricia G. C.; Zaidan,Lilian B. P.
Fonte: Sociedade Botânica de São Paulo Publicador: Sociedade Botânica de São Paulo
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/06/1997 PT
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RESUMO - (Estudos de desenvolvimento de Viguiera robusta Gardn., uma Asteraceae do cerrado). Com o objetivo de se conhecer alguns aspectos da fisiologia de plantas do componente herbáceo da vegetação de cerrado, foram estudados aspectos do desenvolvimento de Viguiera robusta. As plantas, obtidas a partir de sementes (aquênios), foram mantidas sob condições fotoperiódicas controladas, acompanhando-se seu crescimento vegetativo e floração, no subseqüente período de crescimento. Os aquênios germinaram melhor sob luz constantes e às temperaturas de 30ºC e 20/30ºC permanecendo viáveis após 12 meses de armazenamento a 5ºC em frascos de vidro fechados. Sob fotoperíodo de 8 h houve menor crescimento vegetativo. A floração ocorre inicialmente nos fotoperíodos mais curtos e, no decorrer do tempo, também nos fotoperíodos mais longos; sob dias longos-curtos a floração também foi constatada. Plantas em fotoperíodo de 8 h apresentaram maior número de capítulos desenvolvidos. Plantas jovens têm folhas opostas, havendo depois o aparecimento de folhas alternas, não estando esta alteração na filotaxia relacionada com a indução da floração. A ocorrência da floração provoca a liberação de gemas laterais, que formam novos ramos...

Carbon Dioxide Output as an Index of Circadian Timing in Lemna Photoperiodism 1

Hillman, William S.
Fonte: PubMed Publicador: PubMed
Tipo: Artigo de Revista Científica
Publicado em /03/1970 EN
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Previous work on flowering suggested that photoperiodism in Lemna perpusilla 6746 involves an endogenous circadian “clock,” but direct evidence requires study of an overt rhythm in the same plant. The CO2 output rate of axenic cultures supplied with sucrose has been studied in a system using infrared analysis and monitoring four sets of cultures at once. Alternations of ¼ to 21 hours of dim red light with darkness in 24-hour cycles can entrain the CO2 output. In darkness following either continuous dim red light or entrainment to a 12(12) light (dark) schedule, the rate oscillates through two maxima and two minima, with a circadian periodicity, before apparently damping. In continuous red light, the rate is linear. The skeleton photoperiodic schedule ¼(5½)¼(18), with its two portions highly unequal, rapidly entrains the CO2 output in a phase relationship which is the same irrespective of which dark period is given first. The schedules ¼(13)¼(10½) and its inverse, however, with two portions more nearly equal in length, differ markedly from each other with respect to manner of entrainment, as they do in their effects on flowering. These and other results strongly support the concept that a circadian clock is an important component of photoperiodism...

Quantitative Trait Loci Associated with Photoperiodic Response and Stage of Diapause in the Pitcher-Plant Mosquito, Wyeomyia smithii

Mathias, Derrick; Jacky, Lucien; Bradshaw, William E.; Holzapfel, Christina M.
Fonte: Copyright © 2007 by the Genetics Society of America Publicador: Copyright © 2007 by the Genetics Society of America
Tipo: Artigo de Revista Científica
Publicado em /05/2007 EN
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A wide variety of temperate animals rely on length of day (photoperiodism) to anticipate and prepare for changing seasons by regulating the timing of development, reproduction, dormancy, and migration. Although the molecular basis of circadian rhythms regulating daily activities is well defined, the molecular basis for the photoperiodic regulation of seasonal activities is largely unknown. We use geographic variation in the photoperiodic control of diapause in the pitcher-plant mosquito Wyeomyia smithii to create the first QTL map of photoperiodism in any animal. For critical photoperiod (CPP), we detect QTL that are unique, a QTL that is sex linked, QTL that overlap with QTL for stage of diapause (SOD), and a QTL that interacts epistatically with the circadian rhythm gene, timeless. Results presented here confirm earlier studies concluding that CPP is under directional selection over the climatic gradient of North America and that the evolution of CPP is genetically correlated with SOD. Despite epistasis between timeless and a QTL for CPP, timeless is not located within any detectable QTL, indicating that it plays an ancillary role in the evolution of photoperiodism in W. smithii. Finally, we highlight one region of the genome that includes loci contributing to CPP...

Similarities in the circadian clock and photoperiodism in plants

Song, Young Hun; Ito, Shogo; Imaizumi, Takato
Fonte: PubMed Publicador: PubMed
Tipo: Artigo de Revista Científica
Publicado em /10/2010 EN
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Plants utilize circadian clocks to synchronize their physiological and developmental events with daily and yearly changes in the environment. Recent advances in Arabidopsis research have provided a better understanding of the molecular mechanisms of the circadian clock and photoperiodism. One of the most important questions is whether the mechanisms studied in Arabidopsis are conserved in other plants. Homologs of many Arabidopsis clock genes have been identified in various plants and some gene functions have been characterized. It seems that the circadian clocks in plants are similar. Recent success in molecular genetics has also revealed the mechanisms of photoperiodic flowering in cereals. The day-length sensing mechanisms appear to have diverged more between long-day plants and short-day plants than the circadian clock.

Influence of Photoperiod on Hormones, Behavior, and Immune Function

Walton, James C.; Weil, Zachary M.; Nelson, Randy J.
Fonte: PubMed Publicador: PubMed
Tipo: Artigo de Revista Científica
EN
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Photoperiodism is the ability of plants and animals to measure environmental day length to ascertain time of year. Central to the evolution of photoperiodism in animals is the adaptive distribution of energetically challenging activities across the year to optimize reproductive fitness while balancing the energetic tradeoffs necessary for seasonally- appropriate survival strategies. The ability to accurately predict future events requires endogenous mechanisms to permit physiological anticipation of annual conditions. Day length provides a virtually noise free environmental signal to monitor and accurately predict time of the year. In mammals, melatonin provides the hormonal signal transducing day length. Duration of pineal melatonin is inversely related to day length and its secretion drives enduring changes in many physiological systems, including the HPA, HPG, and brain-gut axes, the autonomic nervous system, and the immune system. Thus, melatonin is the fulcrum mediating redistribution of energetic investment among physiological processes to maximize fitness and survival.

Circadian Clock Gene Per2 Is Not Necessary for the Photoperiodic Response in Mice

Ikegami, Keisuke; Iigo, Masayuki; Yoshimura, Takashi
Fonte: Public Library of Science Publicador: Public Library of Science
Tipo: Artigo de Revista Científica
Publicado em 07/03/2013 EN
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In mammals, light information received by the eyes is transmitted to the pineal gland via the circadian pacemaker, i.e., the suprachiasmatic nucleus (SCN). Melatonin secreted by the pineal gland at night decodes night length and regulates seasonal physiology and behavior. Melatonin regulates the expression of the β-subunit of thyroid-stimulating hormone (TSH; Tshb) in the pars tuberalis (PT) of the pituitary gland. Long day-induced PT TSH acts on ependymal cells in the mediobasal hypothalamus to induce the expression of type 2 deiodinase (Dio2) and reduce type 3 deiodinase (Dio3) that are thyroid hormone-activating and hormone-inactivating enzymes, respectively. The long day-activated thyroid hormone T3 regulates seasonal gonadotropin-releasing hormone secretion. It is well established that the circadian clock is involved in the regulation of photoperiodism. However, the involvement of the circadian clock gene in photoperiodism regulation remains unclear. Although mice are generally considered non-seasonal animals, it was recently demonstrated that mice are a good model for the study of photoperiodism. In the present study, therefore, we examined the effect of changing day length in Per2 deletion mutant mice that show shorter wheel-running rhythms under constant darkness followed by arhythmicity. Although the amplitude of clock gene (Per1...

Seasonal Time Measurement During Reproduction

IKEGAMI, Keisuke; YOSHIMURA, Takashi
Fonte: The Society for Reproduction and Development Publicador: The Society for Reproduction and Development
Tipo: Artigo de Revista Científica
EN
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17.56%
Most species living outside the tropical zone undergo physiological adaptations to seasonal environmental changes and changing day length (photoperiod); this phenomenon is called photoperiodism. It is well known that the circadian clock is involved in the regulation of photoperiodism such as seasonal reproduction, but the mechanism underlying circadian clock regulation of photoperiodism remains unclear. Recent molecular analysis have revealed that, in mammals and birds, the pars tuberalis (PT) of the pituitary gland acts as the relay point from light receptors, which receive information about the photoperiod, to the endocrine responses. Long-day (LD)-induced thyroid-stimulating hormone (TSH) in the PT acts as a master regulator of seasonal reproduction in the ependymal cells (ECs) within the mediobasal hypothalamus (MBH) and activates thyroid hormone (TH) by inducing the expression of type 2 deiodinase in both LD and short-day (SD) breeding animals. Furthermore, the circadian clock has been found to be localized in the PT and ECs as well as in the circadian pacemaker(s). This review purposes to summarize the current knowledge concerning the involvement of the neuroendocrine system and circadian clock in seasonal reproduction.

N-acetyltransferase (nat) Is a Critical Conjunct of Photoperiodism between the Circadian System and Endocrine Axis in Antheraea pernyi

Mohamed, Ahmed A. M.; Wang, Qiushi; Bembenek, Jadwiga; Ichihara, Naoyuki; Hiragaki, Susumu; Suzuki, Takeshi; Takeda, Makio
Fonte: Public Library of Science Publicador: Public Library of Science
Tipo: Artigo de Revista Científica
Publicado em 25/03/2014 EN
Relevância na Pesquisa
27.89%
Since its discovery in 1923, the biology of photoperiodism remains a mystery in many ways. We sought the link connecting the circadian system to an endocrine switch, using Antheraea pernyi. PER-, CLK- and CYC-ir were co-expressed in two pairs of dorsolateral neurons of the protocerebrum, suggesting that these are the circadian neurons that also express melatonin-, NAT- and HIOMT-ir. The results suggest that a melatonin pathway is present in the circadian neurons. Melatonin receptor (MT2 or MEL-1B-R)-ir in PTTH-ir neurons juxtaposing clock neurons suggests that melatonin gates PTTH release. RIA showed a melatonin rhythm with a peak four hours after lights off in adult brain both under LD16∶8 (LD) and LD12∶12 (SD), and both the peak and the baseline levels were higher under LD than SD, suggesting a photoperiodic influence. When pupae in diapause were exposed to 10 cycles of LD, or stored at 4°C for 4 months under constant darkness, an increase of NAT activity was observed when PTTH released ecdysone. DNA sequence upstream of nat contained E-boxes to which CYC/CLK could bind, and nat transcription was turned off by clk or cyc dsRNA. dsRNANAT caused dysfunction of photoperiodism. dsRNAPER upregulated nat transcription as anticipated...

Genetic architecture of main effect QTL for heading date in European winter wheat

Zanke, Christine; Ling, Jie; Plieske, Jörg; Kollers, Sonja; Ebmeyer, Erhard; Korzun, Viktor; Argillier, Odile; Stiewe, Gunther; Hinze, Maike; Beier, Sebastian; Ganal, Martin W.; Röder, Marion S.
Fonte: Frontiers Media S.A. Publicador: Frontiers Media S.A.
Tipo: Artigo de Revista Científica
Publicado em 20/05/2014 EN
Relevância na Pesquisa
17.56%
A genome-wide association study (GWAS) for heading date (HD) was performed with a panel of 358 European winter wheat (Triticum aestivum L.) varieties and 14 spring wheat varieties through the phenotypic evaluation of HD in field tests in eight environments. Genotyping data consisted of 770 mapped microsatellite loci and 7934 mapped SNP markers derived from the 90K iSelect wheat chip. Best linear unbiased estimations (BLUEs) were calculated across all trials and ranged from 142.5 to 159.6 days after the 1st of January with an average value of 151.4 days. Considering only associations with a −log10 (P-value) ≥ 3.0, a total of 340 SSR and 2983 SNP marker-trait associations (MTAs) were detected. After Bonferroni correction for multiple testing, a total of 72 SSR and 438 SNP marker-trait associations remained significant. Highly significant MTAs were detected for the photoperiodism gene Ppd-D1, which was genotyped in all varieties. Consistent associations were found on all chromosomes with the highest number of MTAs on chromosome 5B. Linear regression showed a clear dependence of the HD score BLUEs on the number of favorable alleles (decreasing HD) and unfavorable alleles (increasing HD) per variety meaning that genotypes with a higher number of favorable or a low number of unfavorable alleles showed lower HD and therefore flowered earlier. For the vernalization gene Vrn-A2 co-locating MTAs on chromosome 5A...

Phylogeny and oscillating expression of period and cryptochrome in short and long photoperiods suggest a conserved function in Nasonia vitripennis

Bertossa, Rinaldo C.; van de Zande, Louis; Beukeboom, Leo W.; Beersma, Domien G. M.
Fonte: Informa Healthcare USA, Inc. Publicador: Informa Healthcare USA, Inc.
Tipo: Artigo de Revista Científica
EN
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Photoperiodism, the ability to respond to seasonal varying day length with suitable life history changes, is a common trait in organisms that live in temperate regions. In most studied organisms, the circadian system appears to be the basis for photoperiodic time measurement. In insects this is still controversial: while some data indicate that the circadian system is causally involved in photoperiodism, others suggest that it may have a marginal or indirect role. Resonance experiments in the parasitic wasp Nasonia vitripennis have revealed a circadian component in photoperiodic time measurement compatible with a mechanism of internal coincidence where a two components oscillator system obtains information from dawn and dusk, respectively. The identity of this oscillator (or oscillators) is still unclear but possible candidates are the oscillating molecules of the auto-regulatory feedback loops in the heart of the circadian system. Here, we show for the first time the circadian oscillation of period and cryptochrome mRNAs in the heads of Nasonia females kept under short and long photoperiods. Period and cryptochrome mRNA levels display a synchronous oscillation in all conditions tested and persist, albeit with reduced amplitude, during the first day in constant light as well as constant darkness. More importantly...

Evolution of photoperiodic time measurement is independent of the circadian clock in the pitcher-plant mosquito, Wyeomyia smithii

Emerson, Kevin J.; Dake, Sabrina J.; Bradshaw, William E.; Holzapfel, Christina M.
Fonte: PubMed Publicador: PubMed
Tipo: Artigo de Revista Científica
EN
Relevância na Pesquisa
17.56%
For over 70 years, researchers have debated whether the ability to use day length as a cue for the timing of seasonal events (photoperiodism) is related to the endogenous circadian clock that regulates the timing of daily events. Models of photoperiodism include two components: (1) a photoperiodic timer that measures the length of the day, and (2) a photoperiodic counter that elicits the downstream photoperiodic response after a threshold number of days has been counted. Herein, we show that there is no geographical pattern of genetic association between the expression of the circadian clock and the photoperiodic timer or counter. We conclude that the photoperiodic timer and counter have evolved independently of the circadian clock in the pitcher-plant mosquito Wyeomyia smithii and hence, the evolutionary modification of photoperiodism throughout the range of W. smithii has not been causally mediated by a corresponding evolution of the circadian clock.

Structures and functions of insect arylalkylamine N-acetyltransferase (iaaNAT); a key enzyme for physiological and behavioral switch in arthropods

Hiragaki, Susumu; Suzuki, Takeshi; Mohamed, Ahmed A. M.; Takeda, Makio
Fonte: Frontiers Media S.A. Publicador: Frontiers Media S.A.
Tipo: Artigo de Revista Científica
Publicado em 13/04/2015 EN
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The evolution of N-acetyltransfeases (NATs) seems complex. Vertebrate arylalkylamine N-acetyltransferase (aaNAT) has been extensively studied since it leads to the synthesis of melatonin, a multifunctional neurohormone prevalent in photoreceptor cells, and is known as a chemical token of the night. Melatonin also serves as a scavenger for reactive oxygen species. This is also true with invertebrates. NAT therefore has distinct functional implications in circadian function, as timezymes (aaNAT), and also xenobiotic reactions (arylamine NAT or simply NAT). NATs belong to a broader enzyme group, the GCN5-related N-acetyltransferase superfamily. Due to low sequence homology and a seemingly fast rate of structural differentiation, the nomenclature for NATs can be confusing. The advent of bioinformatics, however, has helped to classify this group of enzymes; vertebrates have two distinct subgroups, the timezyme type and the xenobiotic type, which has a wider substrate range including imidazolamine, pharmacological drugs, environmental toxicants and even histone. Insect aaNAT (iaaNAT) form their own clade in the phylogeny, distinct from vertebrate aaNATs. Arthropods are unique, since the phylum has exoskeleton in which quinones derived from N-acetylated monoamines function in coupling chitin and arthropodins. Monoamine oxidase (MAO) activity is limited in insects...

Analysis of main effect QTL for thousand grain weight in European winter wheat (Triticum aestivum L.) by genome-wide association mapping

Zanke, Christine D.; Ling, Jie; Plieske, Jörg; Kollers, Sonja; Ebmeyer, Erhard; Korzun, Viktor; Argillier, Odile; Stiewe, Gunther; Hinze, Maike; Neumann, Felix; Eichhorn, Andrea; Polley, Andreas; Jaenecke, Cornelia; Ganal, Martin W.; Röder, Marion S.
Fonte: Frontiers Media S.A. Publicador: Frontiers Media S.A.
Tipo: Artigo de Revista Científica
Publicado em 01/09/2015 EN
Relevância na Pesquisa
17.24%
Grain weight, an essential yield component, is under strong genetic control and at the same time markedly influenced by the environment. Genetic analysis of the thousand grain weight (TGW) by genome-wide association study (GWAS) was performed with a panel of 358 European winter wheat (Triticum aestivum L.) varieties and 14 spring wheat varieties using phenotypic data of field tests in eight environments. Wide phenotypic variations were indicated for the TGW with BLUEs (best linear unbiased estimations) values ranging from 35.9 to 58.2 g with a mean value of 45.4 g and a heritability of H2 = 0.89. A total of 12 candidate genes for plant height, photoperiodism and grain weight were genotyped on all varieties. Only three candidates, the photoperiodism gene Ppd-D1, dwarfing gene Rht-B1and the TaGW-6A gene were significant explaining up to 14.4, 2.3, and 3.4% of phenotypic variation, respectively. For a comprehensive genome-wide analysis of TGW-QTL genotyping data from 732 microsatellite markers and a set of 7769 mapped SNP-markers genotyped with the 90k iSELECT array were analyzed. In total, 342 significant (-log10 (P-value) ≥ 3.0) marker trait associations (MTAs) were detected for SSR-markers and 1195 MTAs (−log10(P-value) ≥ 3.0) for SNP-markers in all single environments plus the BLUEs. After Bonferroni correction...

Photoperiodic plasticity in circadian clock neurons in insects

Shiga, Sakiko
Fonte: Frontiers Media S.A. Publicador: Frontiers Media S.A.
Tipo: Artigo de Revista Científica
Publicado em 23/08/2013 EN
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17.56%
Since Bünning's observation of circadian rhythms and photoperiodism in the runner bean Phaseolus multiflorus in 1936, many studies have shown that photoperiodism is based on the circadian clock system. In insects, involvement of circadian clock genes or neurons has been recently shown in the photoperiodic control of developmental arrests, diapause. Photoperiod sets peaks of period (per) or timeless (tim) mRNA abundance at lights-off in Sarcophaga crassipalpis, Chymomyza costata and Protophormia terraenovae. Abundance of per and Clock mRNA changes by photoperiod in Pyrrhocoris apterus. Subcellular Per distribution in circadian clock neurons changes with photoperiod in P. terraenovae. Although photoperiodism is not known in Leucophaea maderae, under longer day length, more stomata and longer commissural fibers of circadian clock neurons have been found. These plastic changes in the circadian clock neurons could be an important constituent for photoperiodic clock mechanisms to integrate repetitive photoperiodic information and produce different outputs based on day length.

Influência lunar sobre plantas hortícolas

Simão, Salim
Fonte: Universidade de São Paulo. Escola Superior de Agricultura Luiz de Queiroz Publicador: Universidade de São Paulo. Escola Superior de Agricultura Luiz de Queiroz
Tipo: info:eu-repo/semantics/article; info:eu-repo/semantics/publishedVersion; ; ; ; ; ; Formato: application/pdf
Publicado em 01/01/1958 POR
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The aim of this paper is the study of moon effects on ten different crops divided in four groups: 1) salad and cole crops (lettuce, endive, cabbage, cauliflower); 2) root crops (beet, carrot, radish, turnip); 3) bulb crops (onion); 4) solanaceous fruits (eggplant). The design of the experiment was randomized blocks, with four replications, the different treatments being the four phases of the moon. The analyses of variance are given in the work of Simão (1953) and the analises of the mean in tables 1 to 2. The main conclusions are: 1) No difference in production were found related to different moon phases, even it the crops supposed to be sensible to moon effects. 2) In a few cases, where some increase in production was observed, such increase could be atributed by other apents 3) The agents supposed to interfere with increase in production were temperature and photoperiodism, rather than moon phases. 4) The most sensible crops to low temperature, during the night, were: lettuce, endive, cauliflower, cabbage, carrots, turnips and radish. 5) The most sensible crops to both low temperature and photoperiodism were: onion and beet. 6) The moon phases supposed to have opposed effects, namely full-moon and half-moon, gave mixed results sometimes both giving the best yield simultaneously and sometimes giving the poorest crops. 7) As a final conclusion...