14 documents found, page 1 of 2
Differential physiological responses in rice upon exposure to excess distinct i...
Müller, Caroline; Kuki, Kacilda Naomi; Pinheiro, Daniel Teixeira; Souza, Laíse Rosado de; Silva, Advânio Inácio Siqueira; Loureiro, Marcelo EhlersRice can be cultivated in highlands, which can expose it to iron deficiency, or under irrigation, which can lead to iron toxicity and lower productivity. This study aimed to investigate the strategies used by rice plants under different divalent and trivalent sources of iron excess. Rice plants from a lowland and upland cultivar were grown in nutrient solution with toxic concentrations of ferrous or ferric iron...
Effects of long-term soil drought on photosynthesis and carbohydrate metabolism...
Praxedes, Sidney Carlos; DaMatta, Fábio Murilo; Loureiro, Marcelo Ehlers; Ferrão, Maria A. G.; Cordeiro, Antônio T.Four clones of robusta coffee representing drought-tolerant (14 and 120) and drought-sensitive (46 and 109A) genotypes were submitted to a slowly imposed water deficit. Sampling and measurements were performed when predawn leaf water potential (Ψpd) approximately −2.0 and −3.0 MPa was reached. Regardless of the clone evaluated, drought led to sharper decreases in stomatal conductance than in photosynthesis, whi...
Guard cell-specific down-regulation of the sucrose transporter SUT1 leads to im...
Antunes, Werner Camargos; Daloso, Danilo de Menezes; Pinheiro, Daniela Pereira; Williams, Thomas Christopher Rhys; Loureiro, Marcelo EhlersSucrose is a key metabolite in guard cell (GC) regulation and has been proposed to form a key metabolic connection between mesophyll cells and GCs. However, the importance of sucrose transport across the GC plasma membrane in stomatal movements remains to be determined. Here, we characterized transgenic tobacco plants expressing an antisense gene construct for the SUCROSE TRANSPORTER 1 (SUT1) driven by the GC s...
Inducing flowering in Noccaea caerulescens (J. & C. Presl) F. K. Mey (Brassicac...
Loureiro, Marcelo Ehlers; Guimarães, Marcelo de Almeida; Salt, David EdwardNoccaea caerulescens (J. & C. Presl) F. K. Mey (Brassicaceae) é uma planta muito utilizada em estudos de hiperacumulação de metais como Cd, Ni e Zn. Considerada espécie bienal, sendo propagada basicamente por sementes, apresenta longo período de tempo para a geração de novos indivíduos, o que prejudica consideravelmente o desenvolvimento de novos estudos com esta espécie. Baseado no exposto objetivou-se neste t...
Influência de temperatura, luz e giberelina na germinação de sementes de Thlasp...
Guimarães, Marcelo de Almeida; Vidigal, Deborah de Souza; Loureiro, Marcelo Ehlers; Dias, Denise Cunha Fernandes dos Santos; Guimarães, Amanda RodriguesThlaspi caerulescens é espécie hiperacumuladora de metais como Cd2+, Ni2+ e Zn2+, considerada como uma plantamodelo para estudar a acumulação e tolerância a metais pesados. No entanto, a baixa produção de sementes em nossas condições climáticas tornam necessária a determinação de condições que possam maximizar a germinação e o vigor de suas sementes. Para identificar as melhores condições para a germinação, sem...
Expressão de genes da subfamília HD-Zip I em soja submetida à seca
Pereira, Alan Alves; Morales, Aguida Maria Alves Pereira; Borém, Aluízio; Loureiro, Marcelo EhlersO objetivo deste trabalho foi identificar genes candidatos da subfamília de fatores transcricionais HD-Zip I que contribuem para a tolerância à seca em soja. Foram avaliados trifólios de soja de cultivar tolerante (Embrapa 48) e suscetível à seca (BR 16), sob três níveis de deficit hídrico: ausência, moderado (-1,5 MPa) e severo (-3,0 MPa). Pela análise dos promotores, foi identificada a presença de possíveis e...
Reciprocal grafting between clones with contrasting drought tolerance suggests ...
Silva, Vânia Aparecida; Prado, Fernanda Manso; Antunes, Werner Camargos; Paiva, Rita Márcia Cardoso; Ferrão, Maria Amélia Gava; Andrade, Alan CarvalhoThe role of abscisic acid (ABA) in drought tolerance of Coffea canephora is unknown. To determine whether ABA is associated with drought tolerance and if the use of tolerant rootstocks could increase ABA and drought tolerance, we performed reciprocal grafting experiments between clones with contrasting tolerance to drought (clone 109, sensitive; and clone 120, tolerant). Plants were grown in large (120 L) pots ...
High-density genetic mapping for coffee leaf rust resistance
Loureiro, Marcelo Ehlers; Diola, Valdir; Brito, Giovani Greigh de; Caixeta, Eveline Teixeira; Maciel-Zambolim, Eunize; Sakiyama, Ney SussumuCoffee leaf rust caused by the fungus Hemileia vastatrix causes considerable economic losses for coffee producers. Although agrochemical products can provide sufficient disease control, the use of resistant cultivars is a safer alternative. This resistance may be constrained by one or a few genetic factors, mainly those found in material originating from interspecific hybrids. In this study, the genetic analysi...
Methyl jasmonate and salicylic acid are able to modify cell wall but only salic...
Napoleão, Thiago Alves; Soares, Giuliana; Vital, Camilo Elber; Bastos, Carla; Castro, Robson; Loureiro, Marcelo Ehlers; Giordano, AndreaIn addition to playing a key role in the response to environmental changes, cell walls are also considered as a valuable feedstock for cellulosic ethanol. Here we explored the effects of the stress-response hormones, salicylic acid and methyl jasmonate, on cell wall biosynthesis and biomass digestibility in Brachypodium distachyon, a species recently considered as a suitable model for biomass conversion. We fou...
Evidence for the sucrose-binding protein role in carbohydrate metabolism and tr...
Waclawovsky, Alessandro Jaquiel; Loureiro, Marcelo Ehlers; Rocha, Carolina da Silva; Freitas, Rejane do Livramento; Cano, Marco Antonio OlivaDespite the large amount of data regarding sucrose‐binding proteins (SBP), their functions remain largely unknown and controversial. In this investigation we performed a detailed temporal and spatial characterization of the phenotypes related to photosynthesis, sucrose exudation and carbohydrate metabolism in SBP antisense plants to gain insights into the physiological role of SBP. Significant reductions in net...